Economic analysis of pandemic influenza vaccination strategies in Singapore.

PubMed

Lee, Vernon J; Tok, Mei Yin; Chow, Vincent T; Phua, Kai Hong; Ooi, Eng Eong; Tambyah, Paul A; Chen, Mark I

2009-09-22

All influenza pandemic plans advocate pandemic vaccination. However, few studies have evaluated the cost-effectiveness of different vaccination strategies. This paper compares the economic outcomes of vaccination compared with treatment with antiviral agents alone, in Singapore. We analyzed the economic outcomes of pandemic vaccination (immediate vaccination and vaccine stockpiling) compared with treatment-only in Singapore using a decision-based model to perform cost-benefit and cost-effectiveness analyses. We also explored the annual insurance premium (willingness to pay) depending on the perceived risk of the next pandemic occurring. The treatment-only strategy resulted in 690 deaths, 13,950 hospitalization days, and economic cost of USD$497 million. For immediate vaccination, at vaccine effectiveness of >55%, vaccination was cost-beneficial over treatment-only. Vaccine stockpiling is not cost-effective in most scenarios even with 100% vaccine effectiveness. The annual insurance premium was highest with immediate vaccination, and was lower with increased duration to the next pandemic. The premium was also higher with higher vaccine effectiveness, attack rates, and case-fatality rates. Stockpiling with case-fatality rates of 0.4-0.6% would be cost-beneficial if vaccine effectiveness was >80%; while at case-fatality of >5% stockpiling would be cost-beneficial even if vaccine effectiveness was 20%. High-risk sub-groups warrant higher premiums than low-risk sub-groups. The actual pandemic vaccine effectiveness and lead time is unknown. Vaccine strategy should be based on perception of severity. Immediate vaccination is most cost-effective, but requires vaccines to be available when required. Vaccine stockpiling as insurance against worst-case scenarios is also cost-effective. Research and development is therefore critical to develop and stockpile cheap, readily available effective vaccines.

Pertussis vaccination coverage among French parents of infants after 10years of cocoon strategy.

PubMed

Cohen, R; Gaudelus, J; Denis, F; Stahl, J-P; Chevaillier, O; Pujol, P; Martinot, A

2016-06-01

The cocoon strategy against pertussis has been recommended in France since 2004 to indirectly protect young infants who are not yet vaccinated. We aimed to measure vaccination coverage among French parents of infants. A representative sample of 300 mothers and 200 fathers of infants aged <12 months completed a self-administered online questionnaire. They all provided their own vaccination records. Overall, 87% of mothers believed vaccination against pertussis to be important; 83% reported being immunized against pertussis but their vaccination records showed that a third of them was wrong (34%). On the basis of our sample, the 2009-2014 vaccination coverage against pertussis among mothers increased from 22 to 61% (P<0.005); over the same period of time, vaccination coverage against diphtheria, tetanus, and polio remained stable (80%). Vaccination coverage against pertussis among fathers increased from 21 to 42% between 2010 and 2013 (P=0.009). In 2013, one couple out of four (26%) was adequately immunized against pertussis. The cocoon strategy was implemented 10years ago in France but vaccination coverage remains suboptimal among parents of young infants. Healthcare professionals must recommend vaccination against pertussis to young adults and check that their vaccination status is up to date. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

[Economic evaluation on different two-dose-vaccination-strategies related to Measles, Mumps and Rubella Combined Attenuated Live Vaccine].

PubMed

He, H Q; Zhang, B; Yan, R; Li, Q; Fu, J; Tang, X W; Zhou, Y; Deng, X; Xie, S Y

2016-08-10

To evaluate the economic effect of Measles, Mumps and Rubella Combined Attenuated Live Vaccine (MMR) under different two-dose vaccination programs. A hypothetical birth cohort of 750 000 infants over their lifetime, was followed up from birth through death in Zhejiang province. The current MMR vaccination strategie would include three different ones: 1) Childlern were vaccinated with Measles-Rubella Combined Attenuated Live Vaccine and MMR, respectively at the age of 8 months and 18 months. 2) Children receive MMR at 8 months and 18 months, 3) Strategy 1 plus an additional vaccination of MMR at 4 years of age. Incremental cost-effectiveness ratio (ICER), incremental cost-benefit ratio (ICBR) and incremental net benefit (INB) were applied to calculate the health economic difference for Strategy 2 and Strategy 3 as compared to Strategy 1. Univariate sensitivity analysis was used to assess the robustness of results with main parameters, including the rate of immunization coverage, effectiveness of the vaccines, incidence and burdens of the related diseases, cost of vaccines and the vaccination program itself. ICER, ICBR and INB for Strategy 2 and Strategy 3 appeared as 2 012.51∶1 RMB Yuan per case and 4 238.72∶1 RMB Yuan per case, 1∶3.14 and 1∶1.58, 21 277 800 RMB Yuan and 9 276 500 RMB Yuan, respectively. Only slight changes (<20%) were found under the univariate sensitivity analysis, with varied values on main parameters. Based on the current national immunization program, infants vaccinated with MMR at 8 months of age, generated more health economic effects than the Strategy 3.

[Pertussis in fully vaccinated infants and children. Are new vaccination strategies required?].

PubMed

Moraga-Llop, Fernando A; Mendoza-Palomar, Natàlia; Muntaner-Alonso, Antoni; Codina-Grau, Gemma; Fàbregas-Martori, Anna; Campins-Martí, Magda

2014-04-01

To analyse the vaccination status of children diagnosed with pertussis and to compare the clinical manifestations of fully vaccinated with unvaccinated, or incompletely-vaccinated, children. The clinical histories and vaccination cards of patients under 16years of age seen in the Emergency Room of the University Hospital Vall d'Hebron, Barcelona (Spain), for pertussis confirmed by a microbiological study were reviewed. The study period lasted from January 1, 2009 to December 31, 2011. Two hundred and twelve cases were studied: 35 in 2009, 28 in 2010 and 149 in 2011. RT-PCR was positive in 210 patients, and 73 had a positive culture. Infants under 6months of age account for 36.8% of all cases. Forty-four patients (21.5%) were not vaccinated. Forty-four (21.5%) children were between 2 and 5months of age and had received 1-2vaccine doses. One hundred and seventeen (57%) children were fully vaccinated; 76.9% (90cases) had received the last dose less than 4years ago. When clinical manifestations of the fully vaccinated patients were compared with those of the non-vaccinated or incompletely-vaccinated children, only cyanosis was found with a higher frequency in the latter group (P<.001). The age-adjusted probability of hospitalisation was significantly associated with non-vaccination (P=.001). The case mortality rate among inpatients was 1.3%. The number of pertussis cases seen in our centre has risen significantly in the last year. More than half (57%) of the patients were fully vaccinated, and 76.9% had received the last dose in the previous 4years. Other vaccination strategies, such as vaccination of adolescents, adults, and pregnant women, as well as a cocoon strategy are required to protect infants under 6months of age. More effective vaccines need to be developed. Copyright © 2012 Elsevier España, S.L. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Killed whole-HIV vaccine; employing a well established strategy for antiviral vaccines.

PubMed

Kang, C Yong; Gao, Yong

2017-09-12

The development of an efficient prophylactic HIV vaccine has been one of the major challenges in infectious disease research during the last three decades. Here, we present a mini review on strategies employed for the development of HIV vaccines with an emphasis on a well-established vaccine technology, the killed whole-virus vaccine approach. Recently, we reported an evaluation of the safety and the immunogenicity of a genetically modified and killed whole-HIV-1 vaccine designated as SAV001 [1]. HIV-1 Clade B NL4-3 was genetically modified by deleting the nef and vpu genes and substituting the coding sequence of the Env signal peptide with that of honeybee melittin to produce an avirulent and replication efficient HIV-1. This genetically modified virus (gmHIV-1 NL4-3 ) was propagated in a human T cell line followed by virus purification and inactivation by aldrithiol-2 and γ-irradiation. We found that SAV001 was well tolerated with no serious adverse events. HIV-1 NL4-3 -specific polymerase chain reaction showed no evidence of vaccine virus replication in participants receiving SAV001 and in human T cells infected in vitro. Furthermore, SAV001 with an adjuvant significantly increased the antibody response to HIV-1 structural proteins. Moreover, antibodies in the plasma from these vaccinations neutralized tier I and tier II of HIV-1 B, A, and D subtypes. These results indicated that the killed whole-HIV vaccine is safe and may trigger appropriate immune responses to prevent HIV infection. Utilization of this killed whole-HIV vaccine strategy may pave the way to develop an effective HIV vaccine.

Novel vaccine strategies against emerging viruses

PubMed Central

García-Sastre, Adolfo; Mena, Ignacio

2013-01-01

One of the main public health concerns of emerging viruses is their potential introduction into and sustained circulation among populations of immunologically naïve, susceptible hosts. The induction of protective immunity through vaccination can be a powerful tool to prevent this concern by conferring protection to the population at risk. Conventional approaches to develop vaccines against emerging pathogens have significant limitations: lack of experimental tools for several emerging viruses of concern, poor immunogenicity, safety issues, or lack of cross-protection against antigenic variants. The unpredictability of the emergence of future virus threats demands the capability to rapidly develop safe, effective vaccines. We describe some recent advances in new vaccine strategies that are being explored as alternatives to classical attenuated and inactivated vaccines, and provide examples of potential novel vaccines for emerging viruses. These approaches might be applied to the control of many other emerging pathogens. PMID:23477832

Cost-Effectiveness Analysis of Hepatitis B Vaccination Strategies to Prevent Perinatal Transmission in North Korea: Selective Vaccination vs. Universal Vaccination.

PubMed

Lee, Donghoon; Park, Sang Min

2016-01-01

To tackle the high prevalence of Hepatitis B virus (HBV) infection in North Korea, it is essential that birth doses of HBV vaccines should be administered within 24 hours of birth. As the country fails to provide a Timely Birth Dose (TBD) of HBV vaccine, the efforts of reducing the high prevalence of HBV have been significantly hampered. To examine the cost-effectiveness of vaccination strategies to prevent perinatal transmission of HBV in North Korea, we established a decision tree with a Markov model consisting of selective, universal, and the country's current vaccination program against HBV. The cost-effectiveness analysis was performed from societal and payer's perspectives and evaluated by Disability Adjusted Life Year (DALY). The results suggest that introducing the universal vaccination would prevent 1,866 cases of perinatal infections per 100,000 of the birth cohort of 2013. Furthermore, 900 cases of perinatal infections per 100,000 could be additionally averted if switching to the selective vaccination. The current vaccination is a dominated strategy both from the societal and payer's perspective. The Incremental Cost-Effectiveness Ratio (ICER) between universal and selective vaccination is $267 from the societal perspective and is reported as $273 from the payer's perspective. Based on the assumption that the 2012 Gross Domestic Product (GDP) per capita in North Korea, $582.6 was set for cost-effectiveness criteria, the result of this study indicates that selective vaccination may be a highly cost-effective strategy compared to universal vaccination.

Misinformation lingers in memory: Failure of three pro-vaccination strategies.

PubMed

Pluviano, Sara; Watt, Caroline; Della Sala, Sergio

2017-01-01

People's inability to update their memories in light of corrective information may have important public health consequences, as in the case of vaccination choice. In the present study, we compare three potentially effective strategies in vaccine promotion: one contrasting myths vs. facts, one employing fact and icon boxes, and one showing images of non-vaccinated sick children. Beliefs in the autism/vaccines link and in vaccines side effects, along with intention to vaccinate a future child, were evaluated both immediately after the correction intervention and after a 7-day delay to reveal possible backfire effects. Results show that existing strategies to correct vaccine misinformation are ineffective and often backfire, resulting in the unintended opposite effect, reinforcing ill-founded beliefs about vaccination and reducing intentions to vaccinate. The implications for research on vaccines misinformation and recommendations for progress are discussed.

Misinformation lingers in memory: Failure of three pro-vaccination strategies

PubMed Central

Pluviano, Sara

2017-01-01

People’s inability to update their memories in light of corrective information may have important public health consequences, as in the case of vaccination choice. In the present study, we compare three potentially effective strategies in vaccine promotion: one contrasting myths vs. facts, one employing fact and icon boxes, and one showing images of non-vaccinated sick children. Beliefs in the autism/vaccines link and in vaccines side effects, along with intention to vaccinate a future child, were evaluated both immediately after the correction intervention and after a 7-day delay to reveal possible backfire effects. Results show that existing strategies to correct vaccine misinformation are ineffective and often backfire, resulting in the unintended opposite effect, reinforcing ill-founded beliefs about vaccination and reducing intentions to vaccinate. The implications for research on vaccines misinformation and recommendations for progress are discussed. PMID:28749996

Experiences of operational costs of HPV vaccine delivery strategies in Gavi-supported demonstration projects

PubMed Central

Holroyd, Taylor; Nanda, Shreya; Bloem, Paul; Griffiths, Ulla K.; Sidibe, Anissa; Hutubessy, Raymond C. W.

2017-01-01

From 2012 to 2016, Gavi, the Vaccine Alliance, provided support for countries to conduct small-scale demonstration projects for the introduction of the human papillomavirus vaccine, with the aim of determining which human papillomavirus vaccine delivery strategies might be effective and sustainable upon national scale-up. This study reports on the operational costs and cost determinants of different vaccination delivery strategies within these projects across twelve countries using a standardized micro-costing tool. The World Health Organization Cervical Cancer Prevention and Control Costing Tool was used to collect costing data, which were then aggregated and analyzed to assess the costs and cost determinants of vaccination. Across the one-year demonstration projects, the average economic and financial costs per dose amounted to US$19.98 (standard deviation ±12.5) and US$8.74 (standard deviation ±5.8), respectively. The greatest activities representing the greatest share of financial costs were social mobilization at approximately 30% (range, 6–67%) and service delivery at about 25% (range, 3–46%). Districts implemented varying combinations of school-based, facility-based, or outreach delivery strategies and experienced wide variation in vaccine coverage, drop-out rates, and service delivery costs, including transportation costs and per diems. Size of target population, number of students per school, and average length of time to reach an outreach post influenced cost per dose. Although the operational costs from demonstration projects are much higher than those of other routine vaccine immunization programs, findings from our analysis suggest that HPV vaccination operational costs will decrease substantially for national introduction. Vaccination costs may be decreased further by annual vaccination, high initial investment in social mobilization, or introducing/strengthening school health programs. Our analysis shows that drivers of cost are dependent on

Experiences of operational costs of HPV vaccine delivery strategies in Gavi-supported demonstration projects.

PubMed

Botwright, Siobhan; Holroyd, Taylor; Nanda, Shreya; Bloem, Paul; Griffiths, Ulla K; Sidibe, Anissa; Hutubessy, Raymond C W

2017-01-01

From 2012 to 2016, Gavi, the Vaccine Alliance, provided support for countries to conduct small-scale demonstration projects for the introduction of the human papillomavirus vaccine, with the aim of determining which human papillomavirus vaccine delivery strategies might be effective and sustainable upon national scale-up. This study reports on the operational costs and cost determinants of different vaccination delivery strategies within these projects across twelve countries using a standardized micro-costing tool. The World Health Organization Cervical Cancer Prevention and Control Costing Tool was used to collect costing data, which were then aggregated and analyzed to assess the costs and cost determinants of vaccination. Across the one-year demonstration projects, the average economic and financial costs per dose amounted to US$19.98 (standard deviation ±12.5) and US$8.74 (standard deviation ±5.8), respectively. The greatest activities representing the greatest share of financial costs were social mobilization at approximately 30% (range, 6-67%) and service delivery at about 25% (range, 3-46%). Districts implemented varying combinations of school-based, facility-based, or outreach delivery strategies and experienced wide variation in vaccine coverage, drop-out rates, and service delivery costs, including transportation costs and per diems. Size of target population, number of students per school, and average length of time to reach an outreach post influenced cost per dose. Although the operational costs from demonstration projects are much higher than those of other routine vaccine immunization programs, findings from our analysis suggest that HPV vaccination operational costs will decrease substantially for national introduction. Vaccination costs may be decreased further by annual vaccination, high initial investment in social mobilization, or introducing/strengthening school health programs. Our analysis shows that drivers of cost are dependent on

[Strategies to improve influenza vaccination coverage in Primary Health Care].

PubMed

Antón, F; Richart, M J; Serrano, S; Martínez, A M; Pruteanu, D F

2016-04-01

Vaccination coverage reached in adults is insufficient, and there is a real need for new strategies. To compare strategies for improving influenza vaccination coverage in persons older than 64 years. New strategies were introduced in our health care centre during 2013-2014 influenza vaccination campaign, which included vaccinating patients in homes for the aged as well as in the health care centre. A comparison was made on vaccination coverage over the last 4 years in 3 practices of our health care centre: P1, the general physician vaccinated patients older than 64 that came to the practice; P2, the general physician systematically insisted in vaccination in elderly patients, strongly advising to book appointments, and P3, the general physician did not insist. These practices looked after P1: 278; P2: 320; P3: 294 patients older than 64 years. Overall/P1/P2/P3 coverages in 2010: 51.2/51.4/55/46.9% (P=NS), in 2011: 52.4/52.9/53.8/50.3% (P=NS), in 2012: 51.9/52.5/55.3/47.6% (P=NS), and in 2013: 63.5/79.1/59.7/52.7 (P=.000, P1 versus P2 and P3; P=NS between P2 and P3). Comparing the coverages in 2012-2013 within each practice P1 (P=.000); P2 (P=.045); P3 (P=.018). In P2 and P3 all vaccinations were given by the nurses as previously scheduled. In P3, 55% of the vaccinations were given by the nurses, 24.1% by the GP, 9.7% rejected vaccination, and the remainder did not come to the practice during the vaccination period (October 2013-February 2014). The strategy of vaccinating in the homes for the aged improved the vaccination coverage by 5% in each practice. The strategy of "I've got you here, I jab you here" in P1 improved the vaccination coverage by 22%. Copyright © 2014 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

Cost-Effectiveness Analysis of Hepatitis B Vaccination Strategies to Prevent Perinatal Transmission in North Korea: Selective Vaccination vs. Universal Vaccination

PubMed Central

Lee, Donghoon; Park, Sang Min

2016-01-01

Background To tackle the high prevalence of Hepatitis B virus (HBV) infection in North Korea, it is essential that birth doses of HBV vaccines should be administered within 24 hours of birth. As the country fails to provide a Timely Birth Dose (TBD) of HBV vaccine, the efforts of reducing the high prevalence of HBV have been significantly hampered. Methods To examine the cost-effectiveness of vaccination strategies to prevent perinatal transmission of HBV in North Korea, we established a decision tree with a Markov model consisting of selective, universal, and the country’s current vaccination program against HBV. The cost-effectiveness analysis was performed from societal and payer’s perspectives and evaluated by Disability Adjusted Life Year (DALY). Results The results suggest that introducing the universal vaccination would prevent 1,866 cases of perinatal infections per 100,000 of the birth cohort of 2013. Furthermore, 900 cases of perinatal infections per 100,000 could be additionally averted if switching to the selective vaccination. The current vaccination is a dominated strategy both from the societal and payer’s perspective. The Incremental Cost-Effectiveness Ratio (ICER) between universal and selective vaccination is $267 from the societal perspective and is reported as $273 from the payer’s perspective. Conclusion Based on the assumption that the 2012 Gross Domestic Product (GDP) per capita in North Korea, $582.6 was set for cost-effectiveness criteria, the result of this study indicates that selective vaccination may be a highly cost-effective strategy compared to universal vaccination. PMID:27802340

Financial evaluation of different vaccination strategies for controlling the bluetongue virus serotype 8 epidemic in The Netherlands in 2008.

PubMed

Velthuis, Annet G J; Mourits, Monique C M; Saatkamp, Helmut W; de Koeijer, Aline A; Elbers, Armin R W

2011-05-04

Bluetongue (BT) is a vector-borne disease of ruminants caused by bluetongue virus that is transmitted by biting midges (Culicoides spp.). In 2006, the introduction of BTV serotype 8 (BTV-8) caused a severe epidemic in Western and Central Europe. The principal effective veterinary measure in response to BT was believed to be vaccination accompanied by other measures such as movement restrictions and surveillance. As the number of vaccine doses available at the start of the vaccination campaign was rather uncertain, the Dutch Ministry of Agriculture, Nature and Food Quality and the Dutch agricultural industry wanted to evaluate several different vaccination strategies. This study aimed to rank eight vaccination strategies based on their efficiency (i.e. net costs in relation to prevented losses or benefits) for controlling the bluetongue virus serotype 8 epidemic in 2008. An economic model was developed that included the Dutch professional cattle, sheep and goat sectors together with the hobby farms. Strategies were evaluated based on the least cost - highest benefit frontier, the benefit-cost ratio and the total net returns. Strategy F, where all adult sheep at professional farms in The Netherlands would be vaccinated was very efficient at lowest costs, whereas strategy D, where additional to all adult sheep at professional farms also all adult cattle in the four Northern provinces would be vaccinated, was also very efficient but at a little higher costs. Strategy C, where all adult sheep and cattle at professional farms in the whole of The Netherlands would be vaccinated was also efficient but again at higher costs. This study demonstrates that a financial analysis differentiates between vaccination strategies and indicates important decision rules based on efficiency.

Strategies and hurdles using DNA vaccines to fish

PubMed Central

2014-01-01

DNA vaccinations against fish viral diseases as IHNV at commercial level in Canada against VHSV at experimental level are both success stories. DNA vaccination strategies against many other viral diseases have, however, not yet yielded sufficient results in terms of protection. There is an obvious need to combat many other viral diseases within aquaculture where inactivated vaccines fail. There are many explanations to why DNA vaccine strategies against other viral diseases fail to induce protective immune responses in fish. These obstacles include: 1) too low immunogenicity of the transgene, 2) too low expression of the transgene that is supposed to induce protection, 3) suboptimal immune responses, and 4) too high degradation rate of the delivered plasmid DNA. There are also uncertainties with regard distribution and degradation of DNA vaccines that may have implications for safety and regulatory requirements that need to be clarified. By combining plasmid DNA with different kind of adjuvants one can increase the immunogenicity of the transgene antigen – and perhaps increase the vaccine efficacy. By using molecular adjuvants with or without in combination with targeting assemblies one may expect different responses compared with naked DNA. This includes targeting of DNA vaccines to antigen presenting cells as a central factor in improving their potencies and efficacies by means of encapsulating the DNA vaccine in certain carriers systems that may increase transgene and MHC expression. This review will focus on DNA vaccine delivery, by the use of biodegradable PLGA particles as vehicles for plasmid DNA mainly in fish. PMID:24552235

Understanding HIV infection for the design of a therapeutic vaccine. Part II: Vaccination strategies for HIV.

PubMed

de Goede, A L; Vulto, A G; Osterhaus, A D M E; Gruters, R A

2015-05-01

HIV infection leads to a gradual loss CD4(+) T lymphocytes comprising immune competence and progression to AIDS. Effective treatment with combined antiretroviral drugs (cART) decreases viral load below detectable levels but is not able to eliminate the virus from the body. The success of cART is frustrated by the requirement of expensive lifelong adherence, accumulating drug toxicities and chronic immune activation resulting in increased risk of several non-AIDS disorders, even when viral replication is suppressed. Therefore, there is a strong need for therapeutic strategies as an alternative to cART. Immunotherapy, or therapeutic vaccination, aims to increase existing immune responses against HIV or induce de novo immune responses. These immune responses should provide a functional cure by controlling viral replication and preventing disease progression in the absence of cART. The key difficulty in the development of an HIV vaccine is our ignorance of the immune responses that control of viral replication, and thus how these responses can be elicited and how they can be monitored. Part one of this review provides an extensive overview of the (patho-) physiology of HIV infection. It describes the structure and replication cycle of HIV, the epidemiology and pathogenesis of HIV infection and the innate and adaptive immune responses against HIV. Part two of this review discusses therapeutic options for HIV. Prevention modalities and antiretroviral therapy are briefly touched upon, after which an extensive overview on vaccination strategies for HIV is provided, including the choice of immunogens and delivery strategies. Copyright © 2014. Published by Elsevier Masson SAS.

Vaccine Development for Zika Virus-Timelines and Strategies.

PubMed

Durbin, Anna P

2016-09-01

Zika virus is a mosquito-borne Flavivirus that spread rapidly through South and Central America in 2015 to 2016. Microcephaly has been causally associated with Zika virus infection during pregnancy and the World Health Organization declared Zika virus as a Public Health Emergency of International Concern. To address this crisis, many groups have expressed their commitment to developing a Zika virus vaccine. Different strategies for Zika virus vaccine development are being considered including recombinant live attenuated vaccines, purified inactivated vaccines (PIVs), DNA vaccines, and viral vectored vaccines. Important to Zika virus vaccine development will be the target group chosen for vaccination and which end point(s) is chosen for efficacy determination. The first clinical trials of Zika virus vaccine candidates will begin in Q3/4 2016 but the pathway to licensure for a Zika virus vaccine is expected to take several years. Efforts are ongoing to accelerate Zika virus vaccine development and evaluation with the ultimate goal of reducing time to licensure. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Financial Evaluation of Different Vaccination Strategies for Controlling the Bluetongue Virus Serotype 8 Epidemic in the Netherlands in 2008

PubMed Central

Velthuis, Annet G. J.; Mourits, Monique C. M.; Saatkamp, Helmut W.; de Koeijer, Aline A.; Elbers, Armin R. W.

2011-01-01

Background Bluetongue (BT) is a vector-borne disease of ruminants caused by bluetongue virus that is transmitted by biting midges (Culicoides spp.). In 2006, the introduction of BTV serotype 8 (BTV-8) caused a severe epidemic in Western and Central Europe. The principal effective veterinary measure in response to BT was believed to be vaccination accompanied by other measures such as movement restrictions and surveillance. As the number of vaccine doses available at the start of the vaccination campaign was rather uncertain, the Dutch Ministry of Agriculture, Nature and Food Quality and the Dutch agricultural industry wanted to evaluate several different vaccination strategies. This study aimed to rank eight vaccination strategies based on their efficiency (i.e. net costs in relation to prevented losses or benefits) for controlling the bluetongue virus serotype 8 epidemic in 2008. Methodology/Principal Findings An economic model was developed that included the Dutch professional cattle, sheep and goat sectors together with the hobby farms. Strategies were evaluated based on the least cost - highest benefit frontier, the benefit-cost ratio and the total net returns. Strategy F, where all adult sheep at professional farms in the Netherlands would be vaccinated was very efficient at lowest costs, whereas strategy D, where additional to all adult sheep at professional farms also all adult cattle in the four Northern provinces would be vaccinated, was also very efficient but at a little higher costs. Strategy C, where all adult sheep and cattle at professional farms in the whole of the Netherlands would be vaccinated was also efficient but again at higher costs. Conclusions/Significance This study demonstrates that a financial analysis differentiates between vaccination strategies and indicates important decision rules based on efficiency. PMID:21573195

Rational design of vaccine targets and strategies for HIV: a crossroad of statistical physics, biology, and medicine.

PubMed

Chakraborty, Arup K; Barton, John P

2017-03-01

Vaccination has saved more lives than any other medical procedure. Pathogens have now evolved that have not succumbed to vaccination using the empirical paradigms pioneered by Pasteur and Jenner. Vaccine design strategies that are based on a mechanistic understanding of the pertinent immunology and virology are required to confront and eliminate these scourges. In this perspective, we describe just a few examples of work aimed to achieve this goal by bringing together approaches from statistical physics with biology and clinical research.

Rational design of vaccine targets and strategies for HIV: a crossroad of statistical physics, biology, and medicine

NASA Astrophysics Data System (ADS)

Chakraborty, Arup K.; Barton, John P.

2017-03-01

Vaccination has saved more lives than any other medical procedure. Pathogens have now evolved that have not succumbed to vaccination using the empirical paradigms pioneered by Pasteur and Jenner. Vaccine design strategies that are based on a mechanistic understanding of the pertinent immunology and virology are required to confront and eliminate these scourges. In this perspective, we describe just a few examples of work aimed to achieve this goal by bringing together approaches from statistical physics with biology and clinical research.

Impact of Coverage-Dependent Marginal Costs on Optimal HPV Vaccination Strategies

PubMed Central

Ryser, Marc D.; McGoff, Kevin; Herzog, David P.; Sivakoff, David J.; Myers, Evan R.

2015-01-01

The effectiveness of vaccinating males against the human papillomavirus (HPV) remains a controversial subject. Many existing studies conclude that increasing female coverage is more effective than diverting resources into male vaccination. Recently, several empirical studies on HPV immunization have been published, providing evidence of the fact that marginal vaccination costs increase with coverage. In this study, we use a stochastic agent-based modeling framework to revisit the male vaccination debate in light of these new findings. Within this framework, we assess the impact of coverage-dependent marginal costs of vaccine distribution on optimal immunization strategies against HPV. Focusing on the two scenarios of ongoing and new vaccination programs, we analyze different resource allocation policies and their effects on overall disease burden. Our results suggest that if the costs associated with vaccinating males are relatively close to those associated with vaccinating females, then coverage-dependent, increasing marginal costs may favor vaccination strategies that entail immunization of both genders. In particular, this study emphasizes the necessity for further empirical research on the nature of coverage-dependent vaccination costs. PMID:25979280

Development of an epitope-based HIV-1 vaccine strategy from HIV-1 lipopeptide to dendritic-based vaccines.

PubMed

Surenaud, Mathieu; Lacabaratz, Christine; Zurawski, Gérard; Lévy, Yves; Lelièvre, Jean-Daniel

2017-10-01

Development of a safe, effective and globally affordable Human Immunodeficiency Virus strain 1 (HIV-1) vaccine offers the best hope for future control of the HIV-1 pandemic. However, with the exception of the recent RV144 trial, which elicited a modest level of protection against infection, no vaccine candidate has shown efficacy in preventing HIV-1 infection or in controlling virus replication in humans. There is also a great need for a successful immunotherapeutic vaccine since combination antiretroviral therapy (cART) does not eliminate the reservoir of HIV-infected cells. But to date, no vaccine candidate has proven to significantly alter the natural history of an individual with HIV-1 infection. Areas covered: For over 25 years, the ANRS (France Recherche Nord&Sud Sida-HIV hépatites) has been committed to an original program combining basic science and clinical research developing an epitope-based vaccine strategy to induce a multiepitopic cellular response against HIV-1. This review describes the evolution of concepts, based on strategies using HIV-1 lipopeptides towards the use of dendritic cell (DC) manipulation. Expert commentary: Understanding the crucial role of DCs in immune responses allowed moving from the non-specific administration of HIV-1 sequences with lipopeptides to DC-based vaccines. These DC-targeting strategies should improve HIV-1 vaccine efficacy.

Influenza vaccine strategies for solid organ transplant recipients.

PubMed

Hirzel, Cédric; Kumar, Deepali

2018-05-15

The aim of this study was to highlight recent evidence on important aspects of influenza vaccination in solid organ transplant recipients. Influenza vaccine is the most evaluated vaccine in transplant recipients. The immunogenicity of the vaccine is suboptimal after transplantation. Newer formulations such as inactivated unadjuvanted high-dose influenza vaccine and the administration of a booster dose within the same season have shown to increase response rates. Intradermal vaccination and adjuvanted vaccines did not show clear benefit over standard influenza vaccines. Recent studies in transplant recipients do not suggest a higher risk for allograft rejection, neither after vaccination with a standard influenza vaccine nor after the administration of nonstandard formulation (high-dose, adjuvanted vaccines), routes (intradermally) or a booster dose. Nevertheless, influenza vaccine coverage in transplant recipients is still unsatisfactory low, potentially due to misinterpretation of risks and benefits. Annual influenza vaccination is well tolerated and is an important part of long-term care of solid organ transplant recipients.

Evaluating vaccination strategies to control foot-and-mouth disease: a model comparison study.

PubMed

Roche, S E; Garner, M G; Sanson, R L; Cook, C; Birch, C; Backer, J A; Dube, C; Patyk, K A; Stevenson, M A; Yu, Z D; Rawdon, T G; Gauntlett, F

2015-04-01

Simulation models can offer valuable insights into the effectiveness of different control strategies and act as important decision support tools when comparing and evaluating outbreak scenarios and control strategies. An international modelling study was performed to compare a range of vaccination strategies in the control of foot-and-mouth disease (FMD). Modelling groups from five countries (Australia, New Zealand, USA, UK, The Netherlands) participated in the study. Vaccination is increasingly being recognized as a potentially important tool in the control of FMD, although there is considerable uncertainty as to how and when it should be used. We sought to compare model outputs and assess the effectiveness of different vaccination strategies in the control of FMD. Using a standardized outbreak scenario based on data from an FMD exercise in the UK in 2010, the study showed general agreement between respective models in terms of the effectiveness of vaccination. Under the scenario assumptions, all models demonstrated that vaccination with 'stamping-out' of infected premises led to a significant reduction in predicted epidemic size and duration compared to the 'stamping-out' strategy alone. For all models there were advantages in vaccinating cattle-only rather than all species, using 3-km vaccination rings immediately around infected premises, and starting vaccination earlier in the control programme. This study has shown that certain vaccination strategies are robust even to substantial differences in model configurations. This result should increase end-user confidence in conclusions drawn from model outputs. These results can be used to support and develop effective policies for FMD control.

Plant-based anti-HIV-1 strategies: vaccine molecules and antiviral approaches.

PubMed

Scotti, Nunzia; Buonaguro, Luigi; Tornesello, Maria Lina; Cardi, Teodoro; Buonaguro, Franco Maria

2010-08-01

The introduction of highly active antiretroviral therapy has drastically changed HIV infection from an acute, very deadly, to a chronic, long-lasting, mild disease. However, this requires continuous care management, which is difficult to implement worldwide, especially in developing countries. Sky-rocketing costs of HIV-positive subjects and the limited success of preventive recommendations mean that a vaccine is urgently needed, which could be the only effective strategy for the real control of the AIDS pandemic. To be effective, vaccination will need to be accessible, affordable and directed against multiple antigens. Plant-based vaccines, which are easy to produce and administer, and require no cold chain for their heat stability are, in principle, suited to such a strategy. More recently, it has been shown that even highly immunogenic, enveloped plant-based vaccines can be produced at a competitive and more efficient rate than conventional strategies. The high variability of HIV epitopes and the need to stimulate both humoral neutralizing antibodies and cellular immunity suggest the importance of using the plant system: it offers a wide range of possible strategies, from single-epitope to multicomponent vaccines, modulators of the immune response (adjuvants) and preventive molecules (microbicides), either alone or in association with plant-derived monoclonal antibodies, besides the potential use of the latter as therapeutic agents. Furthermore, plant-based anti-HIV strategies can be administered not only parenterally but also by the more convenient and safer oral route, which is a more suitable approach for possible mass vaccination.

Bistability of Evolutionary Stable Vaccination Strategies in the Reinfection SIRI Model.

PubMed

Martins, José; Pinto, Alberto

2017-04-01

We use the reinfection SIRI epidemiological model to analyze the impact of education programs and vaccine scares on individuals decisions to vaccinate or not. The presence of the reinfection provokes the novelty of the existence of three Nash equilibria for the same level of the morbidity relative risk instead of a single Nash equilibrium as occurs in the SIR model studied by Bauch and Earn (PNAS 101:13391-13394, 2004). The existence of three Nash equilibria, with two of them being evolutionary stable, introduces two scenarios with relevant and opposite features for the same level of the morbidity relative risk: the low-vaccination scenario corresponding to the evolutionary stable vaccination strategy, where individuals will vaccinate with a low probability; and the high-vaccination scenario corresponding to the evolutionary stable vaccination strategy, where individuals will vaccinate with a high probability. We introduce the evolutionary vaccination dynamics for the SIRI model and we prove that it is bistable. The bistability of the evolutionary dynamics indicates that the damage provoked by false scares on the vaccination perceived morbidity risks can be much higher and much more persistent than in the SIR model. Furthermore, the vaccination education programs to be efficient they need to implement a mechanism to suddenly increase the vaccination coverage level.

Cost-effectiveness of three different vaccination strategies against measles in Zambian children.

PubMed

Dayan, Gustavo H; Cairns, Lisa; Sangrujee, Nalinee; Mtonga, Anne; Nguyen, Van; Strebel, Peter

2004-01-02

The vaccination program in Zambia includes one dose of measles vaccine at 9 months of age. The objective of this study was to compare the cost-effectiveness of the current one-dose measles vaccination program with an immunization schedule in which a second dose is provided either through routine health services or through supplemental immunization activities (SIAs). We simulated the expected cost and impact of the vaccination strategies for an annual cohort of 400,000 children, assuming 80% vaccination coverage in both routine and SIAs and an analytic horizon of 15 years. A vaccination program which includes SIAs reaching children not previously vaccinated would prevent on additional 29,242 measles cases and 1462 deaths for each vaccinated birth cohort when compared with a one-dose program. Given the parameters established for this analysis, such a program would be cost-saving and the most cost-effective vaccination strategy for Zambia.

Strategy for distribution of influenza vaccine to high-risk groups and children.

PubMed

Longini, Ira M; Halloran, M Elizabeth

2005-02-15

Despite evidence that vaccinating schoolchildren against influenza is effective in limiting community-level transmission, the United States has had a long-standing government strategy of recommending that vaccine be concentrated primarily in high-risk groups and distributed to those people who keep the health system and social infrastructure operating. Because of this year's influenza vaccine shortage, a plan was enacted to distribute the limited vaccine stock to these groups first. This vaccination strategy, based on direct protection of those most at risk, has not been very effective in reducing influenza morbidity and mortality. Although it is too late to make changes this year, the current influenza vaccine crisis affords the opportunity to examine an alternative for future years. The alternative plan, supported by mathematical models and influenza field studies, would be to concentrate vaccine in schoolchildren, the population group most responsible for transmission, while also covering the reachable high-risk groups, who would also receive considerable indirect protection. In conjunction with a plan to ensure an adequate vaccine supply, this alternative influenza vaccination strategy would help control interpandemic influenza and be instrumental in preparing for pandemic influenza. The effectiveness of the alternative plan could be assessed through nationwide community studies.

A retrospective and prospective look at strategies to increase adolescent HPV vaccine uptake in the United States.

PubMed

Head, Katharine J; Biederman, Erika; Sturm, Lynne A; Zimet, Gregory D

2018-01-23

The HPV vaccine debuted more than ten years ago in the United States and many strategies have been evaluated to increase HPV vaccination rates, which include not only improving current vaccination behaviors but also sustaining these behaviors. Researchers and practitioners from a variety of backgrounds have engaged in this work, which has included efforts directed at public health and government policies, health education and health promotion programs, and clinical and patient-provider approaches, as well as work aimed to respond to and combat anti-HPV vaccination movements in society. Using a previously developed conceptual model to organize and summarize each of these areas, this paper also highlights the need for future HPV vaccine promotion work to adopt a multi-level and, when possible, integrated approach in order to maximize impact on vaccination rates.

Vaccine instability in the cold chain: mechanisms, analysis and formulation strategies.

PubMed

Kumru, Ozan S; Joshi, Sangeeta B; Smith, Dawn E; Middaugh, C Russell; Prusik, Ted; Volkin, David B

2014-09-01

Instability of vaccines often emerges as a key challenge during clinical development (lab to clinic) as well as commercial distribution (factory to patient). To yield stable, efficacious vaccine dosage forms for human use, successful formulation strategies must address a combination of interrelated topics including stabilization of antigens, selection of appropriate adjuvants, and development of stability-indicating analytical methods. This review covers key concepts in understanding the causes and mechanisms of vaccine instability including (1) the complex and delicate nature of antigen structures (e.g., viruses, proteins, carbohydrates, protein-carbohydrate conjugates, etc.), (2) use of adjuvants to further enhance immune responses, (3) development of physicochemical and biological assays to assess vaccine integrity and potency, and (4) stabilization strategies to protect vaccine antigens and adjuvants (and their interactions) during storage. Despite these challenges, vaccines can usually be sufficiently stabilized for use as medicines through a combination of formulation approaches combined with maintenance of an efficient cold chain (manufacturing, distribution, storage and administration). Several illustrative case studies are described regarding mechanisms of vaccine instability along with formulation approaches for stabilization within the vaccine cold chain. These include live, attenuated (measles, polio) and inactivated (influenza, polio) viral vaccines as well as recombinant protein (hepatitis B) vaccines. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

On the robust optimization to the uncertain vaccination strategy problem

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chaerani, D., E-mail: d.chaerani@unpad.ac.id; Anggriani, N., E-mail: d.chaerani@unpad.ac.id; Firdaniza, E-mail: d.chaerani@unpad.ac.id

2014-02-21

In order to prevent an epidemic of infectious diseases, the vaccination coverage needs to be minimized and also the basic reproduction number needs to be maintained below 1. This means that as we get the vaccination coverage as minimum as possible, thus we need to prevent the epidemic to a small number of people who already get infected. In this paper, we discuss the case of vaccination strategy in term of minimizing vaccination coverage, when the basic reproduction number is assumed as an uncertain parameter that lies between 0 and 1. We refer to the linear optimization model for vaccinationmore » strategy that propose by Becker and Starrzak (see [2]). Assuming that there is parameter uncertainty involved, we can see Tanner et al (see [9]) who propose the optimal solution of the problem using stochastic programming. In this paper we discuss an alternative way of optimizing the uncertain vaccination strategy using Robust Optimization (see [3]). In this approach we assume that the parameter uncertainty lies within an ellipsoidal uncertainty set such that we can claim that the obtained result will be achieved in a polynomial time algorithm (as it is guaranteed by the RO methodology). The robust counterpart model is presented.« less

Comparative effectiveness of different strategies of oral cholera vaccination in bangladesh: a modeling study.

PubMed

Dimitrov, Dobromir T; Troeger, Christopher; Halloran, M Elizabeth; Longini, Ira M; Chao, Dennis L

2014-12-01

Killed, oral cholera vaccines have proven safe and effective, and several large-scale mass cholera vaccination efforts have demonstrated the feasibility of widespread deployment. This study uses a mathematical model of cholera transmission in Bangladesh to examine the effectiveness of potential vaccination strategies. We developed an age-structured mathematical model of cholera transmission and calibrated it to reproduce the dynamics of cholera in Matlab, Bangladesh. We used the model to predict the effectiveness of different cholera vaccination strategies over a period of 20 years. We explored vaccination programs that targeted one of three increasingly focused age groups (the entire vaccine-eligible population of age one year and older, children of ages 1 to 14 years, or preschoolers of ages 1 to 4 years) and that could occur either as campaigns recurring every five years or as continuous ongoing vaccination efforts. Our modeling results suggest that vaccinating 70% of the population would avert 90% of cholera cases in the first year but that campaign and continuous vaccination strategies differ in effectiveness over 20 years. Maintaining 70% coverage of the population would be sufficient to prevent sustained transmission of endemic cholera in Matlab, while vaccinating periodically every five years is less effective. Selectively vaccinating children 1-14 years old would prevent the most cholera cases per vaccine administered in both campaign and continuous strategies. We conclude that continuous mass vaccination would be more effective against endemic cholera than periodic campaigns. Vaccinating children averts more cases per dose than vaccinating all age groups, although vaccinating only children is unlikely to control endemic cholera in Bangladesh. Careful consideration must be made before generalizing these results to other regions.

Measles in Morocco: epidemiological profile and impact of vaccination strategy.

PubMed

Cheikh, Amine; Ziani, Mouncif; Cheikh, Zakia; Barakat, Amina; El Menzhi, Omar; Braikat, Mohammed; Benomar, Ali; Cherrah, Yahya; El Hassani, Amine

2015-02-01

Measles continues to persist as one of the leading causes of infant mortality due to preventable diseases through vaccination. This study aims to highlight measles in Morocco, and to present the vaccination strategy implemented to control and eliminate the disease in this country. Throughout this study, and based on data from the Directorate of Epidemiology and Control of Diseases and those of the Directorate of Population, we present an overview on the epidemiological trends of measles from 1997 to 2012, while evoking the plans established by the Ministry of Health (MoH) for the control and elimination of this disease. The number of measles cases has decreased in Morocco between 1997 and 2012 (2574-720 reported cases per year) as a result of four important steps: first, increasing the routine vaccination coverage (73-94%); second, the introduction of the second dose of the combined vaccine against measles and rubella in schools (children aged 6 years) since 2003; third, the first catch-up campaign of vaccination in Morocco in 2008, for which coverage was highly satisfactory (96% and 100% for age groups 5-59 months and 5-14 years, respectively); and fourth, the organization of a mass vaccination campaign in 2013 that targeted children from aged 9 months to 19 years. The vaccination plan and the surveillance system executed in Morocco within the framework of the regional project implemented by the World Health Organization (WHO) to eliminate measles has given remarkable results regarding the reduction of measles cases and mortality due to this disease. According to the data from MoH and WHO, the number of reported and confirmed measles cases decreased drastically during 2014. However, these efforts are still unsatisfactory compared to the prospective of eliminating the disease by 2015.

Zika virus, vaccines, and antiviral strategies.

PubMed

Masmejan, Sophie; Baud, David; Musso, Didier; Panchaud, Alice

2018-06-28

Zika virus (ZIKV) recently emerged as a global public health emergency of international concern. ZIKV is responsible for severe neurological complications in adults and infection during pregnancy and can lead to congenital Zika syndrome. There is no licensed vaccine or drug to prevent or treat ZIKV infection. Areas covered: The aim of this article is to provide an overview and update of the progress of research on anti-ZIKV vaccine and medications until the end of 2017, with a special emphasis on drugs that can be used during pregnancy. Expert commentary: Development of new vaccines and drugs is challenging and several points particular to ZIKV infections augment this difficulty: (1) Cross-reactions between ZIKV and other flaviviruses, the impact of ZIKV vaccination on subsequent flavivirus infections, and vice-versa, is unknown, (2) Drugs against ZIKV should be safe in pregnant women, and (3) Evaluation of the efficacy of vaccine and drugs against ZIKV in clinical trials phase II-IV will be complicated due to the decline of ZIKV circulation.

Comparative Effectiveness of Different Strategies of Oral Cholera Vaccination in Bangladesh: A Modeling Study

PubMed Central

Dimitrov, Dobromir T.; Troeger, Christopher; Halloran, M. Elizabeth; Longini, Ira M.; Chao, Dennis L.

2014-01-01

Background Killed, oral cholera vaccines have proven safe and effective, and several large-scale mass cholera vaccination efforts have demonstrated the feasibility of widespread deployment. This study uses a mathematical model of cholera transmission in Bangladesh to examine the effectiveness of potential vaccination strategies. Methods & Findings We developed an age-structured mathematical model of cholera transmission and calibrated it to reproduce the dynamics of cholera in Matlab, Bangladesh. We used the model to predict the effectiveness of different cholera vaccination strategies over a period of 20 years. We explored vaccination programs that targeted one of three increasingly focused age groups (the entire vaccine-eligible population of age one year and older, children of ages 1 to 14 years, or preschoolers of ages 1 to 4 years) and that could occur either as campaigns recurring every five years or as continuous ongoing vaccination efforts. Our modeling results suggest that vaccinating 70% of the population would avert 90% of cholera cases in the first year but that campaign and continuous vaccination strategies differ in effectiveness over 20 years. Maintaining 70% coverage of the population would be sufficient to prevent sustained transmission of endemic cholera in Matlab, while vaccinating periodically every five years is less effective. Selectively vaccinating children 1–14 years old would prevent the most cholera cases per vaccine administered in both campaign and continuous strategies. Conclusions We conclude that continuous mass vaccination would be more effective against endemic cholera than periodic campaigns. Vaccinating children averts more cases per dose than vaccinating all age groups, although vaccinating only children is unlikely to control endemic cholera in Bangladesh. Careful consideration must be made before generalizing these results to other regions. PMID:25473851

HPV.edu study protocol: a cluster randomised controlled evaluation of education, decisional support and logistical strategies in school-based human papillomavirus (HPV) vaccination of adolescents.

PubMed

Skinner, S Rachel; Davies, Cristyn; Cooper, Spring; Stoney, Tanya; Marshall, Helen; Jones, Jane; Collins, Joanne; Hutton, Heidi; Parrella, Adriana; Zimet, Gregory; Regan, David G; Whyte, Patti; Brotherton, Julia M L; Richmond, Peter; McCaffrey, Kirsten; Garland, Suzanne M; Leask, Julie; Kang, Melissa; Braunack-Mayer, Annette; Kaldor, John; McGeechan, Kevin

2015-09-15

The National Human Papillomavirus (HPV) Vaccination Program in Australia commenced in 2007 for females and in 2013 for males, using the quadrivalent HPV vaccine (HPV 6,11,16,18). Thus far, we have demonstrated very substantial reductions in genital warts and in the prevalence of HPV among young Australian women, providing early evidence for the success of this public health initiative. Australia has a long history of school-based vaccination programs for adolescents, with comparatively high coverage. However, it is not clear what factors promote success in a school vaccination program. The HPV.edu study aims to examine: 1) student knowledge about HPV vaccination; 2) psycho-social outcomes and 3) vaccination uptake. HPV.edu is a cluster randomised trial of a complex intervention in schools aiming to recruit 40 schools with year-8 enrolments above 100 students (approximately 4400 students). The schools will be stratified by Government, Catholic, and Independent sectors and geographical location, with up to 20 schools recruited in each of two states, Western Australia (WA) and South Australia (SA), and randomly allocated to intervention or control (usual practice). Intervention schools will receive the complex intervention which includes an adolescent intervention (education and distraction); a decisional support tool for parents and adolescents and logistical strategies (consent form returns strategies, in-school mop-up vaccination and vaccination-day guidelines). Careful process evaluation including an embedded qualitative evaluation will be undertaken to explore in depth possible mechanisms for any observed effect of the intervention on primary and secondary outcomes. This study is the first to evaluate the relative effectiveness of various strategies to promote best practice in school-based vaccination against HPV. The study aims to improve vaccination-related psychosocial outcomes, including adolescent knowledge and attitudes, decision-making involvement, self

HIV/AIDS vaccines for Africa: scientific opportunities, challenges and strategies

PubMed Central

Chin'ombe, Nyasha; Ruhanya, Vurayai

2015-01-01

More than decades have already elapsed since human immunodeficiency virus (HIV) was identified as the causative agent of acquired immunodeficiency syndrome (AIDS). The HIV has since spread to all parts of the world with devastating effects. In sub-saharan Africa, the HIV/AIDS epidemic has reached unprecedented proportions. Safe, effective and affordable HIV/AIDS vaccines for Africans are therefore urgently needed to contain this public health problem. Although, there are challenges, there are also scientific opportunities and strategies that can be exploited in the development of HIV/AIDS vaccines for Africa. The recent RV144 Phase III trial in Thailand has demonstrated that it is possible to develop a vaccine that can potentially elicit modest protective immunity against HIV infection. The main objective of this review is to outline the key scientific opportunities, challenges and strategies in HIV/AIDS vaccine development in Africa. PMID:26185576

Mucosal vaccination--an old but still vital strategy.

PubMed

Długońska, Henryka; Grzybowski, Marcin

2012-01-01

The basic premise of vaccinology is to achieve strong protective immunity against defined infectious agents by a vaccine mimicking the effects of natural primary exposure to a pathogen. Because an exposure of humans and animals to microbes occurs mostly through mucosal surfaces, targeting the mucosa seems a rational and efficient vaccination strategy. Many experimental and clinical data confirmed that mucosal immunization offers many advantages over widely used in human and veterinary medicine subcutaneous or intramuscular immunization. In the present article selected aspects regarding mucosal vaccination are discussed. The structure and function of mucosa-associated lymphoid tissue (MALT), comprised of four main mucosal compartments forming a structural and functional unity as well as pivotal cellular MALT components (dendritic and M cells) were briefly characterized. Particular attention was focused on the mode of simple but efficacious delivery of vaccine antigens to mucosal surfaces. A few trials to generate potential mucosal vaccines against toxoplasmosis introduced by nasal or oral routes to experimental animals are also presented.

Maternal vaccination as a Salmonella Typhimurium reduction strategy on pig farms.

PubMed

Smith, R P; Andres, V; Martelli, F; Gosling, B; Marco-Jimenez, F; Vaughan, K; Tchorzewska, M; Davies, R

2018-01-01

The control of Salmonella in pig production is necessary for public and animal health, and vaccination was evaluated as a strategy to decrease pig prevalence. The study examined the efficacy of a live Salmonella Typhimurium vaccine, administered to sows on eight commercial farrow-to-finish herds experiencing clinical salmonellosis or Salmonella carriage associated with S. Typhimurium or its monophasic variants. Results of longitudinal Salmonella sampling were compared against eight similarly selected and studied control farms. At the last visit (~14 months after the start of vaccination), when all finishing stock had been born to vaccinated sows, both faecal shedding and environmental prevalence of Salmonella substantially declined on the majority of vaccinated farms in comparison to the controls. A higher proportion of vaccine farms resolved clinical salmonellosis than controls. However, Salmonella counts in positive faeces samples were similar between nonvaccinated and vaccinated herds. The results suggest that maternal vaccination is a suitable option for a Salmonella Typhimurium reduction strategy in farrow-to-finish pig herds. Salmonella vaccines have the potential to reduce the prevalence of Salmonella in pigs and result in a reduction of human cases attributed to pork. © 2017 Crown copyright. Journal of Applied Microbiology © 2017 The Society for Applied Microbiology. This article is published with the permission of the Controller of HMSO and the Queen’s Printer for Scotland.

Comparison of two vaccination strategies against hepatitis A and B in patients with chronic hepatitis C.

PubMed

Díez Redondo, M P; Almaraz, A; Jiménez Rodríguez-Vila, M; Santamaría, A; de Castro, J; Torrego, J C; Caro-Patón, A

2009-04-01

although the vaccination against hepatitis A (VAH) and hepatitis B (VBH) is recommended in patients with HCV, the most cost-effective strategy has not been established. Our objective was to compare the cost-effectiveness of universal strategy (vaccination all patients) with selective strategy (vaccination only patients against virus they lack immunity to) in patients with HCV. we compared the direct medical costs of the two vaccination strategies against both viruses in 313 patients with HC. Serological markers for HAV (anti-HAV) and HBV (HbsAg, anti HBs, anti HBc) were determined in the 313 patients and the costs of the vaccines and the blood tests necessary to determinate the immunity state in our care system were considered. the prevalence of anti-HAV was 81,2% and of anti-HBc was 24,6%. The prevalence of anti-HAV increases with age. HAV vaccination with universal strategy has a cost of 19.806,64 euro and with selective one of 9.899,62 euro. HBV vaccination with universal strategy rose to 18.780 euro and to 20.385,57 euro with selective one (employing anti-HBc). Costs were analysed in different groups of age and several hepatitis HBV risk factors. the selective vaccination strategy against HAV was most cost-effective in our patients with HCV. However, when the prevalence of the anti-HAV decreased to less than 20% universal strategy will be the best option. Difference of cost-effective between the two vaccination strategies against HBV was small, on behalf of universal one, so in groups with higher anti-HBc prevalence, like parenteral drugs users and tattoos, the selective strategy could be the best option.

Strategies to Improve Vaccine Efficacy against Tuberculosis by Targeting Innate Immunity

PubMed Central

Schaible, Ulrich E.; Linnemann, Lara; Redinger, Natalja; Patin, Emmanuel C.; Dallenga, Tobias

2017-01-01

The global tuberculosis epidemic is the most common cause of death after infectious disease worldwide. Increasing numbers of infections with multi- and extensively drug-resistant variants of the Mycobacterium tuberculosis complex, resistant even to newly discovered and last resort antibiotics, highlight the urgent need for an efficient vaccine. The protective efficacy to pulmonary tuberculosis in adults of the only currently available vaccine, M. bovis BCG, is unsatisfactory and geographically diverse. More importantly, recent clinical studies on new vaccine candidates did not prove to be better than BCG, yet. Here, we propose and discuss novel strategies to improve efficacy of existing anti-tuberculosis vaccines. Modulation of innate immune responses upon vaccination already provided promising results in animal models of tuberculosis. For instance, neutrophils have been shown to influence vaccine efficacy, both, positively and negatively, and stimulate specific antibody secretion. Modulating immune regulatory properties after vaccination such as induction of different types of innate immune cell death, myeloid-derived suppressor or regulatory T cells, production of anti-inflammatory cytokines such as IL-10 may have beneficial effects on protection efficacy. Incorporation of lipid antigens presented via CD1 molecules to T cells have been discussed as a way to enhance vaccine efficacy. Finally, concepts of dendritic cell-based immunotherapies or training the innate immune memory may be exploitable for future vaccination strategies against tuberculosis. In this review, we put a spotlight on host immune networks as potential targets to boost protection by old and new tuberculosis vaccines. PMID:29312298

Strategies to Improve Vaccine Efficacy against Tuberculosis by Targeting Innate Immunity.

PubMed

Schaible, Ulrich E; Linnemann, Lara; Redinger, Natalja; Patin, Emmanuel C; Dallenga, Tobias

2017-01-01

The global tuberculosis epidemic is the most common cause of death after infectious disease worldwide. Increasing numbers of infections with multi- and extensively drug-resistant variants of the Mycobacterium tuberculosis complex, resistant even to newly discovered and last resort antibiotics, highlight the urgent need for an efficient vaccine. The protective efficacy to pulmonary tuberculosis in adults of the only currently available vaccine, M. bovis BCG, is unsatisfactory and geographically diverse. More importantly, recent clinical studies on new vaccine candidates did not prove to be better than BCG, yet. Here, we propose and discuss novel strategies to improve efficacy of existing anti-tuberculosis vaccines. Modulation of innate immune responses upon vaccination already provided promising results in animal models of tuberculosis. For instance, neutrophils have been shown to influence vaccine efficacy, both, positively and negatively, and stimulate specific antibody secretion. Modulating immune regulatory properties after vaccination such as induction of different types of innate immune cell death, myeloid-derived suppressor or regulatory T cells, production of anti-inflammatory cytokines such as IL-10 may have beneficial effects on protection efficacy. Incorporation of lipid antigens presented via CD1 molecules to T cells have been discussed as a way to enhance vaccine efficacy. Finally, concepts of dendritic cell-based immunotherapies or training the innate immune memory may be exploitable for future vaccination strategies against tuberculosis. In this review, we put a spotlight on host immune networks as potential targets to boost protection by old and new tuberculosis vaccines.

Rabies control in rural Africa: Evaluating strategies for effective domestic dog vaccination

PubMed Central

Kaare, M.; Lembo, T.; Hampson, K.; Ernest, E.; Estes, A.; Mentzel, C.; Cleaveland, S.

2012-01-01

Effective vaccination campaigns need to reach a sufficient percentage of the population to eliminate disease and prevent future outbreaks, which for rabies is predicted to be 70%, at a cost that is economically and logistically sustainable. Domestic dog rabies has been increasing across most of sub-Saharan Africa indicating that dog vaccination programmes to date have been inadequate. We compare the effectiveness of a variety of dog vaccination strategies in terms of their cost and coverage in different community settings in rural Tanzania. Central-point (CP) vaccination was extremely effective in agro-pastoralist communities achieving a high coverage (>80%) at a low cost (vaccination was costly (>US$5/dog) and inadequate (<20% coverage); combined approaches using CP and either house-to-house vaccination or trained community-based animal health workers were most effective with coverage exceeding 70%, although costs were still high (>US$6 and >US$4/dog, respectively). No single vaccination strategy is likely to be effective in all populations and therefore alternative approaches must be deployed under different settings. CP vaccination is cost-effective and efficient for the majority of dog populations in rural Tanzania and potentially elsewhere in sub-Saharan Africa, whereas a combination strategy is necessary in remote pastoralist communities. These results suggest that rabies control is logistically feasible across most of the developing world and that the annual costs of effective vaccination campaigns in Tanzania are likely to be affordable. PMID:18848595

Comparison of Strategies and Incidence Thresholds for Vi Conjugate Vaccines Against Typhoid Fever: A Cost-effectiveness Modeling Study.

PubMed

Lo, Nathan C; Gupta, Ribhav; Stanaway, Jeffrey D; Garrett, Denise O; Bogoch, Isaac I; Luby, Stephen P; Andrews, Jason R

2018-02-12

Typhoid fever remains a major public health problem globally. While new Vi conjugate vaccines hold promise for averting disease, the optimal programmatic delivery remains unclear. We aimed to identify the strategies and associated epidemiologic conditions under which Vi conjugate vaccines would be cost-effective. We developed a dynamic, age-structured transmission and cost-effectiveness model that simulated multiple vaccination strategies with a typhoid Vi conjugate vaccine from a societal perspective. We simulated 10-year vaccination programs with (1) routine immunization of infants (aged <1 year) through the Expanded Program on Immunization (EPI) and (2) routine immunization of infants through the EPI plus a 1-time catch-up campaign in school-aged children (aged 5-14 years). In the base case analysis, we assumed a 0.5% case-fatality rate for all cases of clinically symptomatic typhoid fever and defined strategies as highly cost-effective by using the definition of a low-income country (defined as a country with a gross domestic product of $1045 per capita). We defined incidence as the true number of clinically symptomatic people in the population per year. Vi conjugate typhoid vaccines were highly cost-effective when administered by routine immunization activities through the EPI in settings with an annual incidence of >50 cases/100000 (95% uncertainty interval, 40-75 cases) and when administered through the EPI plus a catch-up campaign in settings with an annual incidence of >130 cases/100000 (95% uncertainty interval, 50-395 cases). The incidence threshold was sensitive to the typhoid-related case-fatality rate, carrier contribution to transmission, vaccine characteristics, and country-specific economic threshold for cost-effectiveness. Typhoid Vi conjugate vaccines would be highly cost-effective in low-income countries in settings of moderate typhoid incidence (50 cases/100000 annually). These results were sensitive to case-fatality rates, underscoring the

New Strategies Toward Edible Vaccines: An Overview.

PubMed

Aryamvally, Anjali; Gunasekaran, Vignesh; Narenthiran, Keerthana Ragavi; Pasupathi, Rathinasabapathi

2016-04-11

With the ever growing population, advancements in edible vaccines and related technologies have seen a rise in popularity. Antigenic peptides incorporated into an edible part of a plant can be administered raw as a vaccine. While conventional vaccines have improved the quality of life by drastically reducing the onset of diseases, edible vaccines are able to perform the same with greater accessibility and at an affordable price. Low cost of production, ease of storage, transportation and administration are some of the many reasons behind the push for the development of edible vaccines. This article aims at giving an overview of the different plant systems used to produce vaccines in various experiments, as well as the merits and demerits of using that particular expression system. Further, the article elaborates on the problems faced in the production of edible vaccines and the measures adopted to surpass them. The major obstacle in the process is attaining a sufficiently large concentration of foreign antigen in the plant system. The article discusses various plant expression systems like banana, rice, alfalfa, mushroom, potato, tomato, pea, tobacco, and maize. When these were reviewed, it was found that the inability to produce the desired antigen concentration was one of the primary reasons why edible vaccines sometimes fail to generate the desired level of immune response in the recipient. We conclude with a promising solution to the problem by incorporating nano-technological advancements to the already existing protocols for edible vaccine development.

A proposed national strategy for tuberculosis vaccine development.

PubMed

Ginsberg, A M

2000-06-01

The global tuberculosis epidemic causes approximately 5% of deaths worldwide. Despite recent concerted and largely successful tuberculosis control efforts, the incidence of tuberculosis in the United States remains 74-fold higher than the stated elimination goal of <1 case per million population by the year 2010. Current bacille Calmette-Guérin vaccines, although efficacious in preventing extrapulmonary tuberculosis in young children, have shown widely variable efficacy in preventing adult pulmonary tuberculosis, confound skin test screening, and are not recommended for use in the United States. The Advisory Council for Elimination of Tuberculosis recently stated that tuberculosis would not be eliminated from the United States without a more effective vaccine. Recent scientific advances have created unprecedented opportunity for tuberculosis vaccine development. Therefore, members of the broad tuberculosis research and control communities have recently created and proposed a national strategy, or blueprint, for tuberculosis vaccine development, which is presented here.

Cost-effectiveness and public health impact of alternative influenza vaccination strategies in high-risk adults.

PubMed

Raviotta, Jonathan M; Smith, Kenneth J; DePasse, Jay; Brown, Shawn T; Shim, Eunha; Nowalk, Mary Patricia; Wateska, Angela; France, Glenson S; Zimmerman, Richard K

2017-10-09

High-dose trivalent inactivated influenza vaccine (HD-IIV3) or recombinant trivalent influenza vaccine (RIV) may increase influenza vaccine effectiveness (VE) in adults with conditions that place them at high risk for influenza complications. This analysis models the public health impact and cost-effectiveness (CE) of these vaccines for 50-64year-olds. Markov model CE analysis compared 5 strategies in 50-64year-olds: no vaccination; only standard-dose IIV3 offered (SD-IIV3 only), only quadrivalent influenza vaccine offered (SD-IIV4 only); high-risk patients receiving HD-IIV3, others receiving SD-IIV3 (HD-IIV3 & SD-IIV3); and high-risk patients receiving HD-IIV3, others receiving SD-IIV4 (HD-IIV3 & SD-IIV4). In a secondary analysis, RIV replaced HD-IIV3. Parameters were obtained from U.S. databases, the medical literature and extrapolations from VE estimates. Effectiveness was measured as 3%/year discounted quality adjusted life year (QALY) losses avoided. The least expensive strategy was SD-IIV3 only, with total costs of $99.84/person. The SD-IIV4 only strategy cost an additional $0.91/person, or $37,700/QALY gained. The HD-IIV3 & SD-IIV4 strategy cost $1.06 more than SD-IIV4 only, or $71,500/QALY gained. No vaccination and HD-IIV3 & SD-IIV3 strategies were dominated. Results were sensitive to influenza incidence, vaccine cost, standard-dose VE in the entire population and high-dose VE in high-risk patients. The CE of RIV for high-risk patients was dependent on as yet unknown parameter values. Based on available data, using high-dose influenza vaccine or RIV in middle-aged, high-risk patients may be an economically favorable vaccination strategy with public health benefits. Clinical trials of these vaccines in this population may be warranted. Copyright © 2017 Elsevier Ltd. All rights reserved.

Educating on professional habits: attitudes of medical students towards diverse strategies for promoting influenza vaccination and factors associated with the intention to get vaccinated

PubMed Central

2013-01-01

Background Influenza vaccination coverage in medical students is usually low. Unlike health care workers, there is little information on the attitudes to and predictors of vaccination among medical students, and their attitudes towards institutional strategies for improving rates are unknown. Methods This cross-sectional study evaluated the effect of three influenza vaccination promotional strategies (Web page, video and tri-fold brochure) on medical students’ intention to get vaccinated and associated factors. A total of 538 medical students were asked to answer an anonymous questionnaire assessing the intention to get vaccinated after exposure to any of the promotional strategies. Sociodemographic data collected included: sex, age, university year, influenza risk group and cohabiting with member of a risk group. Results Four hundred twenty-one students answered the questionnaire, of whom 312 (74.1%) were female, 113 (26.8%) had done clinical rotations, and 111 (26.6%) reported intention to get the flu shot. Logistic regression showed the web group had a greater intention to get vaccinated than the reference group (OR: 2.42 95% CI: 1.16-5.03). Having done clinical rotations (OR: 2.55 95% CI: 1.36-4.38) and having received the shot in previous flu seasons (OR: 13.69 95% CI: 7.86-23.96) were independently associated with the intention to get vaccinated. Conclusion Given that previous vaccination is a factor associated with the intention to get vaccinated, education on vaccination of health care workers should begin while they are students, thereby potentiating the habit. In addition, the intention to get vaccinated was greater during the clinical phase of the university career, suggesting this is a good time to introduce promotion strategies. Online promotional campaigns, such as a thematic Web to promote vaccination of health workers, could improve the intention to get vaccinated. PMID:23866902

Contagious bovine pleuropneumonia vaccines and control strategies: recent data.

PubMed

Thiaucourt, F; Aboubakar, Y; Wesonga, H; Manso-Silvan, L; Blanchard, A

2004-01-01

Contagious bovine pleuropneumonia is one of the most threatening transboundary cattle disease in Africa. However, with the exception of Botswana, very few African countries were able to implement eradication strategies for this disease, after it had recently re-infected a number of countries. Previous experimental studies have shown that emergency vaccination campaigns, based on a single injection, were not inducing a sufficient protection level to prevent further spread of the disease. In addition, post-vaccinal reactions were sometimes reported in the field when using vaccine strain T1/44, leading cattle owners to refuse the vaccination. On the contrary, antibiotics are used quite often in the field but there are insufficient data to assess their efficacy properly. Therefore experimental studies were implemented: (i) to check if higher dosages of the vaccine would be able to induce higher protection rates and (ii) to elucidate the origin of the post-vaccinal reactions observed with T1/44 and (iii) to gain preliminary results on the efficacy of long-acting tetracycline. The first experiment included the use of three doses of vaccine strains T1/44 and T1sr: 10(7), 10(8) and 10(9) mycoplasmas per dose. T1/44 seemed to induce a higher protection (70%) than T1sr (60%). However, there was no observable dose effect for these vaccine strains. The second experiment was performed by injecting various MmmSC strains subcutaneously into susceptible cattle. One of these strains was an isolate obtained from a "Willems" reaction following a vaccination with T1/44. This isolate, called T1B, induced typical invading oedema at the injection site in a similar way to the pathogenic strain, whereas the original T1/44 vaccine strain did not. These findings indicate that the strain has reverted to virulence. Finally the antibiotic trials showed that long-acting tetracycline was able to reduce the losses due to the disease but could not prevent the persistence of viable MmmSC in treated

Using quality improvement methods to increase use of pain prevention strategies for childhood vaccination.

PubMed

Schurman, Jennifer Verrill; Deacy, Amanda D; Johnson, Rebecca J; Parker, Jolynn; Williams, Kristi; Wallace, Dustin; Connelly, Mark; Anson, Lynn; Mroczka, Kevin

2017-02-08

To increase evidence-based pain prevention strategy use during routine vaccinations in a pediatric primary care clinic using quality improvement methodology. Specific intervention strategies ( i.e ., comfort positioning, nonnutritive sucking and sucrose analgesia, distraction) were identified, selected and introduced in three waves, using a Plan-Do-Study-Act framework. System-wide change was measured from baseline to post-intervention by: (1) percent of vaccination visits during which an evidence-based pain prevention strategy was reported as being used; and (2) caregiver satisfaction ratings following the visit. Additionally, self-reported staff and caregiver attitudes and beliefs about pain prevention were measured at baseline and 1-year post-intervention to assess for possible long-term cultural shifts. Significant improvements were noted post-intervention. Use of at least one pain prevention strategy was documented at 99% of patient visits and 94% of caregivers were satisfied or very satisfied with the pain prevention care received. Parents/caregivers reported greater satisfaction with the specific pain prevention strategy used [ t (143) = 2.50, P ≤ 0.05], as well as greater agreement that the pain prevention strategies used helped their children's pain [ t (180) = 2.17, P ≤ 0.05] and that they would be willing to use the same strategy again in the future [ t (179) = 3.26, P ≤ 0.001] as compared to baseline. Staff and caregivers also demonstrated a shift in attitudes from baseline to 1-year post-intervention. Specifically, staff reported greater agreement that the pain felt from vaccinations can result in harmful effects [2.47 vs 3.10; t (70) = -2.11, P ≤ 0.05], less agreement that pain from vaccinations is "just part of the process" [3.94 vs 3.23; t (70) = 2.61, P ≤ 0.05], and less agreement that parents expect their children to experience pain during vaccinations [4.81 vs 4.38; t (69) = 2.24, P ≤ 0.05]. Parents/caregivers reported more favorable

Perceptions and experiences of childhood vaccination communication strategies among caregivers and health workers in Nigeria: A qualitative study.

PubMed

Oku, Afiong; Oyo-Ita, Angela; Glenton, Claire; Fretheim, Atle; Ames, Heather; Muloliwa, Artur; Kaufman, Jessica; Hill, Sophie; Cliff, Julie; Cartier, Yuri; Owoaje, Eme; Bosch-Capblanch, Xavier; Rada, Gabriel; Lewin, Simon

2017-01-01

Effective vaccination communication with parents is critical in efforts to overcome barriers to childhood vaccination, tackle vaccine hesitancy and improve vaccination coverage. Health workers should be able to provide information to parents and other caregivers and support them in reaching decisions about vaccinating their children. Limited information exists regarding the perceptions of caregivers and health workers on the vaccination communication strategies employed in Nigeria. This study, which forms part of the 'Communicate to vaccinate' (COMMVAC) project, aims to explore the perceptions and experiences of caregivers and health workers in Nigeria on vaccination communication strategies implemented in their settings. We conducted the study in two States: Bauchi in Northern Nigeria and Cross River in the south. We carried out observations (n = 40), in-depth interviews (n = 14) and focus group discussions (FGDs) (n = 12) amongst 14 purposively selected health workers, two community leaders and 84 caregivers in the two states. We transcribed data verbatim and analysed the data using a framework analysis approach. Caregivers were informed about vaccination activities through three main sources: health facilities (during health education sessions conducted at antenatal or immunization clinics); media outlets; and announcements (in churches/mosques, communities and markets). Caregivers reported that the information received was very useful. Their preferred sources of information included phone text messages, town announcers, media and church/mosque announcements. Some caregivers perceived the clinic environment, long waiting times and health worker attitudes as barriers to receiving vaccination information.When delivering communication interventions, health workers described issues tied to poor communication skills; poor motivation; and attitudes of community members, including vaccine resistance. Communication about vaccination involves more than the message but is

Schistosomiasis elimination strategies and potential role of a vaccine in achieving global health goals.

PubMed

Mo, Annie X; Agosti, Jan M; Walson, Judd L; Hall, B Fenton; Gordon, Lance

2014-01-01

In March 2013, the National Institute of Allergy and Infectious Diseases and the Bill and Melinda Gates Foundation co-sponsored a meeting entitled "Schistosomiasis Elimination Strategy and Potential Role of a Vaccine in Achieving Global Health Goals" to discuss the potential role of schistosomiasis vaccines and other tools in the context of schistosomiasis control and elimination strategies. It was concluded that although schistosomiasis elimination in some focal areas may be achievable through current mass drug administration programs, global control and elimination will face several significant scientific and operational challenges, and will require an integrated approach with other, additional interventions. These challenges include vector (snail) control; environmental modification; water, sanitation, and hygiene; and other future innovative tools such as vaccines. Defining a clear product development plan that reflects a vaccine strategy as complementary to the existing control programs to combat different forms of schistosomiasis will be important to develop a vaccine effectively.

Dengue Fever: Causes, Complications, and Vaccine Strategies

PubMed Central

Khanna, Ira

2016-01-01

Dengue is a highly endemic infectious disease of the tropical countries and is rapidly becoming a global burden. It is caused by any of the 4 serotypes of dengue virus and is transmitted within humans through female Aedes mosquitoes. Dengue disease varies from mild fever to severe conditions of dengue hemorrhagic fever and shock syndrome. Globalization, increased air travel, and unplanned urbanization have led to increase in the rate of infection and helped dengue to expand its geographic and demographic distribution. Dengue vaccine development has been a challenging task due to the existence of four antigenically distinct dengue virus serotypes, each capable of eliciting cross-reactive and disease-enhancing antibody response against the remaining three serotypes. Recently, Sanofi Pasteur's chimeric live-attenuated dengue vaccine candidate has been approved in Mexico, Brazil, and Philippines for usage in adults between 9 and 45 years of age. The impact of its limited application to the public health system needs to be evaluated. Simultaneously, the restricted application of this vaccine candidate warrants continued efforts in developing a dengue vaccine candidate which is additionally efficacious for infants and naïve individuals. In this context, alternative strategies of developing a designed vaccine candidate which does not allow production of enhancing antibodies should be explored, as it may expand the umbrella of efficacy to include infants and naïve individuals. PMID:27525287

Future vaccination strategies against tuberculosis: thinking outside the box.

PubMed

Kaufmann, Stefan H E

2010-10-29

With almost a dozen vaccine candidates in clinical trials, tuberculosis (TB) research and development is finally reaping the first fruits of its labors. Vaccine candidates in clinical trials may prevent TB disease reactivation by efficiently containing the pathogen Mycobacterium tuberculosis (Mtb). Future research should target vaccines that achieve sterile eradication of Mtb or even prevent stable infection. These are ambitious goals that can be reached only by highly cooperative engagement of basic immunologists, vaccinologists, and clinical researchers--or in other words, by translation from basic immunology to vaccine research and development, as well as reverse translation of insights from clinical trials back to hypothesis-driven research in the basic laboratory. Here, we review current and future strategies toward the rational design of novel vaccines against TB, as well as the progress made thus far, and the hurdles that need to be overcome in the near and distant future. Copyright © 2010 Elsevier Inc. All rights reserved.

Strategies and actions of multi-purpose health communication on vaccine preventable infectious diseases in order to increase vaccination coverage in the population: The ESCULAPIO project

PubMed Central

Bonanni, Paolo; Lauri, Sara; Tiscione, Emilia; Levi, Miriam; Prato, Rosa; Fortunato, Francesca; Martinelli, Domenico; Gasparini, Roberto; Panatto, Donatella; Amicizia, Daniela; Coppola, Rosa Cristina; Vitale, Francesco; Iannazzo, Stefania

2017-01-01

ABSTRACT The ESCULAPIO Project aims at increasing awareness on vaccine preventable infectious diseases (VPID) and vaccinations in different target populations and to spread the culture of prevention. Information/training interventions on VPID have been developed and health promotion activities for the general population, students and their parents, teachers and health care workers (HCWs) were set up. In Tuscany, educational courses on VPID in high schools were organized and students were stimulated to prepare informative materials on VPID for lower grade school pupils. In Liguria, an educational card game (named ‘Vaccine at the Fair’) was presented to children of primary schools. Stands in shopping centers were used in Palermo to distribute the regional vaccination schedule and gadgets, also providing indications on reliable websites where to find correct information on vaccinations. A music video played by health care workers (HCWs) was created and used in the University Hospital of Cagliari to promote the anti-flu vaccination campaign in HCWs. In Apulia, meetings with the general population were organized to collect controversial issues about vaccinations and a national call center was launched to create a direct line from the general population to experts in vaccines and vaccination strategies. In Veneto, meetings in the birth centers and home visits for subjects refusing vaccination have been organized. All activities are useful and effective tools to increase knowledge about VPID and confidence in vaccination, which are crucial aspects in order to increase vaccine uptake. The project was funded by the Italian Ministry of Health, Center for Disease Prevention and Control (CCM) in 2013. PMID:28215120

Strategies and actions of multi-purpose health communication on vaccine preventable infectious diseases in order to increase vaccination coverage in the population: The ESCULAPIO project.

PubMed

Bechini, Angela; Bonanni, Paolo; Lauri, Sara; Tiscione, Emilia; Levi, Miriam; Prato, Rosa; Fortunato, Francesca; Martinelli, Domenico; Gasparini, Roberto; Panatto, Donatella; Amicizia, Daniela; Coppola, Rosa Cristina; Pellizzari, Barbara; Tabacchi, Garden; Costantino, Claudio; Vitale, Francesco; Iannazzo, Stefania; Boccalini, Sara

2017-02-01

The ESCULAPIO Project aims at increasing awareness on vaccine preventable infectious diseases (VPID) and vaccinations in different target populations and to spread the culture of prevention. Information/training interventions on VPID have been developed and health promotion activities for the general population, students and their parents, teachers and health care workers (HCWs) were set up. In Tuscany, educational courses on VPID in high schools were organized and students were stimulated to prepare informative materials on VPID for lower grade school pupils. In Liguria, an educational card game (named 'Vaccine at the Fair') was presented to children of primary schools. Stands in shopping centers were used in Palermo to distribute the regional vaccination schedule and gadgets, also providing indications on reliable websites where to find correct information on vaccinations. A music video played by health care workers (HCWs) was created and used in the University Hospital of Cagliari to promote the anti-flu vaccination campaign in HCWs. In Apulia, meetings with the general population were organized to collect controversial issues about vaccinations and a national call center was launched to create a direct line from the general population to experts in vaccines and vaccination strategies. In Veneto, meetings in the birth centers and home visits for subjects refusing vaccination have been organized. All activities are useful and effective tools to increase knowledge about VPID and confidence in vaccination, which are crucial aspects in order to increase vaccine uptake. The project was funded by the Italian Ministry of Health, Center for Disease Prevention and Control (CCM) in 2013.

[Use the Markov-decision tree model to optimize vaccination strategies of hepatitis E among women aged 15 to 49].

PubMed

Chen, Z M; Ji, S B; Shi, X L; Zhao, Y Y; Zhang, X F; Jin, H

2017-02-10

Objective: To evaluate the cost-utility of different hepatitis E vaccination strategies in women aged 15 to 49. Methods: The Markov-decision tree model was constructed to evaluate the cost-utility of three hepatitis E virus vaccination strategies. Parameters of the models were estimated on the basis of published studies and experience of experts. Both methods on sensitivity and threshold analysis were used to evaluate the uncertainties of the model. Results: Compared with non-vaccination group, strategy on post-screening vaccination with rate as 100%, could save 0.10 quality-adjusted life years per capital in the women from the societal perspectives. After implementation of screening program and with the vaccination rate reaching 100%, the incremental cost utility ratio (ICUR) of vaccination appeared as 5 651.89 and 6 385.33 Yuan/QALY, respectively. Vaccination post to the implementation of a screening program, the result showed better benefit than the vaccination rate of 100%. Results from the sensitivity analysis showed that both the cost of hepatitis E vaccine and the inoculation compliance rate presented significant effects. If the cost were lower than 191.56 Yuan (RMB) or the inoculation compliance rate lower than 0.23, the vaccination rate of 100% strategy was better than the post-screening vaccination strategy, otherwise the post-screening vaccination strategy appeared the optimal strategy. Conclusion: Post-screening vaccination for women aged 15 to 49 from social perspectives seemed the optimal one but it had to depend on the change of vaccine cost and the rate of inoculation compliance.

Possible global strategies for stopping polio vaccination and how they could be harmonized.

PubMed

Cochi, S L; Sutter, R W; Aylward, R B

2001-01-01

One of the challenges of the polio eradication initiative over the next few years will be the formulation of an optimal strategy for stopping poliovirus vaccination after global certification of polio eradication has been accomplished. This strategy must maximize the benefits and minimize the risks. A number of strategies are currently under consideration, including: (i) synchronized global discontinuation of use of oral poliovirus vaccine (OPV); (ii) regional or subregional coordinated OPV discontinuation; and (iii) moving from trivalent to bivalent or monovalent OPV. Other options include moving from OPV to global use of IPV for an interim period before cessation of IPV use (to eliminate circulation of vaccine-derived poliovirus, if necessary) or development of new OPV strains that are not transmissible. Each of these strategies is associated with specific advantages (financial benefits for OPV discontinuation) and disadvantages (cost of switch to IPV) and inherent uncertainties (risk of continued poliovirus circulation in certain populations or prolonged virus replication in immunodeficient persons). An ambitious research agenda addresses the remaining questions and issues. Nevertheless, several generalities are already clear. Unprecedented collaboration between countries, regions, and indeed the entire world will be required to implement a global OPV discontinuation strategy Regulatory approval will be needed for an interim bivalent OPV or for monovalent OPV in many countries. Manufacturers will need sufficient lead time to produce sufficient quantities of IPV Finally, the financial implications for any of these strategies need to be considered. Whatever strategy is followed it will be necessary to stockpile supplies of a poliovirus-containing vaccine (most probably all three types of monovalent OPV), and to develop contingency plans to respond should an outbreak of polio occur after stopping vaccination.

Schistosomiasis Elimination Strategies and Potential Role of a Vaccine in Achieving Global Health Goals

PubMed Central

Mo, Annie X.; Agosti, Jan M.; Walson, Judd L.; Hall, B. Fenton; Gordon, Lance

2014-01-01

In March 2013, the National Institute of Allergy and Infectious Diseases and the Bill and Melinda Gates Foundation co-sponsored a meeting entitled “Schistosomiasis Elimination Strategy and Potential Role of a Vaccine in Achieving Global Health Goals” to discuss the potential role of schistosomiasis vaccines and other tools in the context of schistosomiasis control and elimination strategies. It was concluded that although schistosomiasis elimination in some focal areas may be achievable through current mass drug administration programs, global control and elimination will face several significant scientific and operational challenges, and will require an integrated approach with other, additional interventions. These challenges include vector (snail) control; environmental modification; water, sanitation, and hygiene; and other future innovative tools such as vaccines. Defining a clear product development plan that reflects a vaccine strategy as complementary to the existing control programs to combat different forms of schistosomiasis will be important to develop a vaccine effectively. PMID:24402703

Current and future vaccines and vaccination strategies against infectious laryngotracheitis (ILT) respiratory disease of poultry.

PubMed

García, Maricarmen

2017-07-01

Infectious laryngotracheitis (ILT) is an economically important respiratory disease of poultry that affects the industry worldwide. Vaccination is the principal tool in the control of the disease. Two types of vaccines, live attenuated and recombinant viral vector, are commercially available. The first generation of GaHV-1 vaccines available since the early 1960's are live viruses, attenuated by continuous passages in cell culture or embryos. These vaccines significantly reduce mortalities and, in particular, the chicken embryo origin (CEO) vaccines have shown to limit outbreaks of the disease. However, the CEO vaccines can regain virulence and become the source of outbreaks. Recombinant viral vector vaccines, the second generation of GaHV-1 vaccines, were first introduced in the early 2000's. These are Fowl Pox virus (FPV) and Herpes virus of turkeys (HVT) vectors expressing one or multiple GaHV-1 immunogenic proteins. Recombinant viral vector vaccines are considered a much safer alternative because they do not regain virulence. In the face of challenge, they improve bird performance and ameliorate clinical signs of the disease but fail to reduce shedding of the challenge virus increasing the likelihood of outbreaks. At the moment, several new strategies are being evaluated to improve both live attenuated and viral vector vaccines. Potential new live vaccines attenuated by deletion of genes associated with virulence or by selection of CEO viral subpopulations that do not exhibit increased virulence upon passages in birds are being evaluated. Also new vector alternatives to express GaHV-1 glycoproteins in Newcastle diseases virus (NDV) or in modified very virulent (vv) serotype I Marek's disease virus (MDV) were developed and evaluated. Copyright © 2016 Elsevier B.V. All rights reserved.

Vaccination Strategies: a comparative study in an epidemic scenario

NASA Astrophysics Data System (ADS)

Prates, D. B.; Jardim, C. L. T. F.; Ferreira, L. A. F.; da Silva, J. M.; Kritz, M. V.

2016-08-01

Epidemics are an extremely important matter of study within the Mathematical Modeling area and can be widely found in the literature. Some epidemiological models use differential equations, which are very sensible to parameters, to represent and describe the diseases mathematically. For this work, a variation of the SIR model is discussed and applied to a certain epidemic scenario, wherein vaccination is introduced through two different strategies: constant vaccination and vaccination in pulses. Other epidemiological and population aspects are also considered, such as mortality/natality and infection rates. The analysis and results are performed through numerical solutions of the model and a special attention is given to the discussion generated by the paramenters variation.

A multi-country study of dengue vaccination strategies with Dengvaxia and a future vaccine candidate in three dengue-endemic countries: Vietnam, Thailand, and Colombia.

PubMed

Lee, Jung-Seok; Lourenço, José; Gupta, Sunetra; Farlow, Andrew

2018-04-19

The dengue vaccination era began when Dengvaxia (CYD-TDV) became available in 2016. In addition, several second-generation vaccine candidates are currently in phase 3 trials, suggesting that a broader availability of dengue vaccines may be possible in the near future. Advancing on the recent WHO-SAGE recommendations for the safe and effective use of CYD-TDV at the regional level on average, this study investigates the vaccination impacts and cost-effectiveness of CYD-TDV and of a hypothetical new vaccine candidate (NVC) in a country-specific manner for three endemic countries: Vietnam, Thailand, and Colombia. The vaccination impacts of CYD-TDV and NVC were derived by fitting the empirical seroprevalence rates of 9 year olds into an individual-based meta-population transmission model, previously used for the WHO-SAGE working group. The disability-adjusted life years were estimated by applying country-specific parametric values. The cost-effectiveness analyses of four intervention strategies in combination with routine and catch-up campaigns were compared for both vaccines to inform decision makers regarding the most suitable immunization program in each of the three countries. Both CYD-TDV and NVC could be cost-effective at the DALY threshold cost of $2000 depending upon vaccination costs. With CYD-TDV, targeting 9 year olds in routine vaccination programs and 10-29 year olds as a one-off catch-up campaign was the most cost-effective strategy in all three countries. With NVC, while the most cost-effective strategy was to vaccinate 9-29 and 9-18 year olds in Vietnam and Thailand respectively, vaccinating younger age cohorts between 1 and 5 years old in Colombia was more cost-effective than other strategies. Given that three countries will soon face decisions regarding whether and how to incorporate CYD-TDV or future dengue vaccines into their budget-constrained national immunization programs, the current study outcomes can be used to help decision makers

A Novel Non-Replication-Competent Cytomegalovirus Capsid Mutant Vaccine Strategy Is Effective in Reducing Congenital Infection

PubMed Central

Choi, K. Yeon; Root, Matthew

2016-01-01

ABSTRACT Congenital cytomegalovirus (CMV) infection is a leading cause of mental retardation and deafness in newborns. The guinea pig is the only small animal model for congenital CMV infection. A novel CMV vaccine was investigated as an intervention strategy against congenital guinea pig cytomegalovirus (GPCMV) infection. In this disabled infectious single-cycle (DISC) vaccine strategy, a GPCMV mutant virus was used that lacked the ability to express an essential capsid gene (the UL85 homolog GP85) except when grown on a complementing cell line. In vaccinated animals, the GP85 mutant virus (GP85 DISC) induced an antibody response to important glycoprotein complexes considered neutralizing target antigens (gB, gH/gL/gO, and gM/gN). The vaccine also generated a T cell response to the pp65 homolog (GP83), determined via a newly established guinea pig gamma interferon enzyme-linked immunosorbent spot assay. In a congenital infection protection study, GP85 DISC-vaccinated animals and a nonvaccinated control group were challenged during pregnancy with wild-type GPCMV (105 PFU). The pregnant animals carried the pups to term, and viral loads in target organs of pups were analyzed. Based on live pup births in the vaccinated and control groups (94.1% versus 63.6%), the vaccine was successful in reducing mortality (P = 0.0002). Additionally, pups from the vaccinated group had reduced CMV transmission, with 23.5% infected target organs versus 75.9% in the control group. Overall, these preliminary studies indicate that a DISC CMV vaccine strategy has the ability to induce an immune response similar to that of natural virus infection but has the increased safety of a non-replication-competent virus, which makes this approach attractive as a CMV vaccine strategy. IMPORTANCE Congenital CMV infection is a leading cause of mental retardation and deafness in newborns. An effective vaccine against CMV remains an elusive goal despite over 50 years of CMV research. The guinea pig, with

Assessing the Effectiveness and Cost-Benefit of Test-and-Vaccinate Policy for Supplementary Vaccination against Rubella with Limited Doses

PubMed Central

Saito, Masaya M.; Kinoshita, Ryo

2018-01-01

Elevating herd immunity level against rubella is essential to prevent congenital rubella syndrome (CRS). Insufficient vaccination coverage left susceptible pockets among adults in Japan, and the outbreak of rubella from 2012 to 2013 resulted in 45 observed CRS cases. Given a limited stock of rubella-containing vaccine (RCV) available, the Japanese government recommended healthcare providers to prioritize vaccination to those confirmed with low level of immunity, or to those likely to transmit to pregnant women. Although a test-and-vaccinate policy could potentially help reduce the use of the limited stockpile of vaccines, by selectively elevating herd immunity, the cost of serological testing is generally high and comparable to the vaccine itself. Here, we aimed to examine whether random vaccination would be more cost-beneficial than the test-and-vaccinate strategy. A mathematical model was employed to evaluate the vaccination policy implemented in 2012–2013, quantifying the benefit-to-cost ratio to achieve herd immunity. The modelling exercise demonstrated that, while the test-and-vaccinate strategy can efficiently achieve herd immunity when stockpiles of RCV are limited, random vaccination would be a more cost-beneficial strategy. As long as the herd immunity acts as the goal of vaccination, our findings apply to future supplementary immunization strategy. PMID:29565821

The cost-effectiveness of alternative vaccination strategies for polyvalent meningococcal vaccines in Burkina Faso: A transmission dynamic modeling study.

PubMed

Yaesoubi, Reza; Trotter, Caroline; Colijn, Caroline; Yaesoubi, Maziar; Colombini, Anaïs; Resch, Stephen; Kristiansen, Paul A; LaForce, F Marc; Cohen, Ted

2018-01-01

The introduction of a conjugate vaccine for serogroup A Neisseria meningitidis has dramatically reduced disease in the African meningitis belt. In this context, important questions remain about the performance of different vaccine policies that target remaining serogroups. Here, we estimate the health impact and cost associated with several alternative vaccination policies in Burkina Faso. We developed and calibrated a mathematical model of meningococcal transmission to project the disability-adjusted life years (DALYs) averted and costs associated with the current Base policy (serogroup A conjugate vaccination at 9 months, as part of the Expanded Program on Immunization [EPI], plus district-specific reactive vaccination campaigns using polyvalent meningococcal polysaccharide [PMP] vaccine in response to outbreaks) and three alternative policies: (1) Base Prime: novel polyvalent meningococcal conjugate (PMC) vaccine replaces the serogroup A conjugate in EPI and is also used in reactive campaigns; (2) Prevention 1: PMC used in EPI and in a nationwide catch-up campaign for 1-18-year-olds; and (3) Prevention 2: Prevention 1, except the nationwide campaign includes individuals up to 29 years old. Over a 30-year simulation period, Prevention 2 would avert 78% of the meningococcal cases (95% prediction interval: 63%-90%) expected under the Base policy if serogroup A is not replaced by remaining serogroups after elimination, and would avert 87% (77%-93%) of meningococcal cases if complete strain replacement occurs. Compared to the Base policy and at the PMC vaccine price of US$4 per dose, strategies that use PMC vaccine (i.e., Base Prime and Preventions 1 and 2) are expected to be cost saving if strain replacement occurs, and would cost US$51 (-US$236, US$490), US$188 (-US$97, US$626), and US$246 (-US$53, US$703) per DALY averted, respectively, if strain replacement does not occur. An important potential limitation of our study is the simplifying assumption that all

Accelerating clinical development of HIV vaccine strategies: methodological challenges and considerations in constructing an optimised multi-arm phase I/II trial design.

PubMed

Richert, Laura; Doussau, Adélaïde; Lelièvre, Jean-Daniel; Arnold, Vincent; Rieux, Véronique; Bouakane, Amel; Lévy, Yves; Chêne, Geneviève; Thiébaut, Rodolphe

2014-02-26

Many candidate vaccine strategies against human immunodeficiency virus (HIV) infection are under study, but their clinical development is lengthy and iterative. To accelerate HIV vaccine development optimised trial designs are needed. We propose a randomised multi-arm phase I/II design for early stage development of several vaccine strategies, aiming at rapidly discarding those that are unsafe or non-immunogenic. We explored early stage designs to evaluate both the safety and the immunogenicity of four heterologous prime-boost HIV vaccine strategies in parallel. One of the vaccines used as a prime and boost in the different strategies (vaccine 1) has yet to be tested in humans, thus requiring a phase I safety evaluation. However, its toxicity risk is considered minimal based on data from similar vaccines. We newly adapted a randomised phase II trial by integrating an early safety decision rule, emulating that of a phase I study. We evaluated the operating characteristics of the proposed design in simulation studies with either a fixed-sample frequentist or a continuous Bayesian safety decision rule and projected timelines for the trial. We propose a randomised four-arm phase I/II design with two independent binary endpoints for safety and immunogenicity. Immunogenicity evaluation at trial end is based on a single-stage Fleming design per arm, comparing the observed proportion of responders in an immunogenicity screening assay to an unacceptably low proportion, without direct comparisons between arms. Randomisation limits heterogeneity in volunteer characteristics between arms. To avoid exposure of additional participants to an unsafe vaccine during the vaccine boost phase, an early safety decision rule is imposed on the arm starting with vaccine 1 injections. In simulations of the design with either decision rule, the risks of erroneous conclusions were controlled <15%. Flexibility in trial conduct is greater with the continuous Bayesian rule. A 12-month gain in

Vaccines and vaccination strategies against human cutaneous leishmaniasis.

PubMed

Okwor, Ifeoma; Uzonna, Jude

2009-05-01

One might think that the development of a vaccine against cutaneous leishmaniasis would be relatively straightforward because the type of immune response required for protection is known and natural immunity occurs following recovery from primary infection. However, there is as yet no effective vaccine against the disease in humans. Although vaccination in murine studies has yielded promising results, these vaccines have failed miserably when tested in primates or humans. The reasons behind these failures are unknown and remain a major hurdle for vaccine design and development against cutaneous leishmaniasis. In contrast, recovery from natural, deliberate or experimental infections results in development of long-lasting immunity to re-infection. This so called infection-induced resistance is the strongest anti-Leishmania immunity known. Here, we briefly review the different approaches to vaccination against cutaneous leishmaniasis and argue that vaccines composed of genetically modified (attenuated) parasites, which induce immunity akin to infection-induced resistance, may provide best protection against cutaneous leishmaniasis in humans.

How does public policy impact cervical screening and vaccination strategies?☆

PubMed Central

Herzog, Thomas J.; Huh, Warner K.; Einstein, Mark H.

2011-01-01

Objectives To examine the current approaches to cervical screening and points to consider for improving HPV vaccination acceptance and uptake in the US. Methods An expert forum was conducted September 12–13, 2008, by the Society of Gynecologic Oncologists including 56 experts in cervical cancer and titled “Future Strategies of Cervical Cancer Prevention: What Do We Need to Do Now to Prepare?”. Results Cervical cancer prevention has primarily relied on screening paradigms but vaccination against human papillomavirus (HPV), the cause of the disease, is a primary preventative measure that has been recommended by all cervical cancer screening stakeholders. Guidelines for vaccination are developed by national advisory groups, but successful implementation requires a supportive infrastructure and the cooperation of providers, clinicians, and patients. HPV vaccination has been available in the United States (US) since 2006 and screening practices have been updated to also include HPV genotyping. However, many clinicians fail to adhere to the guidelines for HPV testing (and HPV co-testing) as part of cervical cancer screening, and vaccination coverage has been poor among females aged 11 and 12, the group for which vaccination is recommended by all organizations. Conclusions The data reviewed and presented in this session of the “Future Strategies of Cervical Cancer Prevention. What Do We Need to do Now to Prepare?”. The Forum suggests that the policies influencing HPV vaccination and screening need to be reassessed at multiple levels in order to achieve more effective implementation and regular use. PMID:20932433

Sex-based biology and the rational design of influenza vaccination strategies.

PubMed

Klein, Sabra L; Pekosz, Andrew

2014-07-15

Biological (ie, sex) differences as well as cultural (ie, gender) norms influence the acceptance and efficacy of vaccines for males and females. These differences are often overlooked in the design and implementation of vaccination strategies. Using seasonal and pandemic influenza vaccines, we document profound differences between the sexes in the acceptance, correlates of protection, and adverse reactions following vaccination in both young and older adults. Females develop higher antibody responses, experience more adverse reactions to influenza vaccines, and show greater vaccine efficacy than males. Despite greater vaccine efficacy in females, both young and older females are often less likely to accept influenza vaccines than their male counterparts. Identification of the biological mechanisms, including the hormones and genes, that underlie differential responses to vaccination is necessary. We propose that vaccines should be matched to an individual's biological sex, which could involve systematically tailoring diverse types of FDA-approved influenza vaccines separately for males and females. One goal for vaccines designed to protect against influenza and even other infectious diseases should be to increase the correlates of protection in males and reduce adverse reactions in females in an effort to increase acceptance and vaccine-induced protection in both sexes. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

DIVA--a vaccination strategy enabling the detection of field exposure to avian influenza.

PubMed

Capua, I; Cattoli, G; Marangon, S

2004-01-01

The present paper reports on the development, validation and field application of a control strategy for avian influenza infections in poultry. The "DIVA" (Differentiating Infected from Vaccinated Animals) strategy is based on the use of an inactivated oil emulsion vaccine containing the same haemagglutinin (H) subtype as the challenge virus, but a different neuraminidase (N). The possibility of using the heterologous N subtype, to differentiate between vaccinated and naturally infected birds, was investigated through the development of an "ad hoc" serological test based on the detection of specific anti-N antibodies. This test is based on an indirect fluorescent antibody assay, using as an antigen a baculovirus expressing recombinant N proteins. The vaccination strategy has been tested in the laboratory and shown to be efficacious both against challenge with highly pathogenic AI viruses and with low pathogenicity AI viruses, ensuring clinical protection, reduction of duration and titre of shedding. In addition, vaccination resulted in an increased resistance to infection. The companion diagnostic tests directed to the detection of anti-N1 and anti-N3 antibodies have been validated in the laboratory and using field samples. The serological assay showed an "almost perfect agreement" (Kappa value) with the HI test, with relative sensitivity and specificity values of 98.1 and 95.7, respectively. The results of the present investigation suggest that the "DIVA" control strategy may represent a tool to support the eradication of avian influenza infections in poultry.

The projected effectiveness of Clostridium difficile vaccination as part of an integrated infection control strategy.

PubMed

van Kleef, Esther; Deeny, Sarah R; Jit, Mark; Cookson, Barry; Goldenberg, Simon D; Edmunds, W John; Robotham, Julie V

2016-11-04

Early clinical trials of a Clostridium difficile toxoid vaccine show efficacy in preventing C. difficile infection (CDI). The optimal patient group to target for vaccination programmes remains unexplored. This study performed a model-based evaluation of the effectiveness of different CDI vaccination strategies, within the context of existing infection prevention and control strategies such as antimicrobial stewardship. An individual-based transmission model of CDI in a high-risk hospital setting was developed. The model incorporated data on patient movements between the hospital, and catchment populations from the community and long-term care facilities (LTCF), using English national and local level data for model-parameterisation. We evaluated vaccination of: (1) discharged patients who had an CDI-occurrence in the ward; (2) LTCF-residents; (3) Planned elective surgical admissions and (4) All three strategies combined. Without vaccination, 10.9 [Interquartile range: 10.0-11.8] patients per 1000 ward admissions developed CDI, of which 31% were ward-acquired. Immunising all three patient groups resulted in a 43% [42-44], reduction of ward-onset CDI on average. Among the strategies restricting vaccination to one target group, vaccinating elective surgical patients proved most effective (35% [34-36] reduction), but least efficient, requiring 146 [133-162] courses to prevent one ICU-onset case. Immunising LTCF residents was most efficient, requiring just 13 [11-16] courses to prevent one case, but considering this only comprised a small group of our hospital population, it only reduced ICU-onset CDI by 9% [8-11]. Vaccination proved most efficient when ward-based transmission rates and antimicrobial consumption were high. Strategy success depends on the interaction between hospital and catchment populations, and importantly, consideration of importations of CDI from outside the hospital which we found to substantially impact hospital dynamics. Vaccination may be most

Development of an intradermal DNA vaccine delivery strategy to achieve single-dose immunity against respiratory syncytial virus.

PubMed

Smith, Trevor R F; Schultheis, Katherine; Morrow, Matthew P; Kraynyak, Kimberly A; McCoy, Jay R; Yim, Kevin C; Muthumani, Karuppiah; Humeau, Laurent; Weiner, David B; Sardesai, Niranjan Y; Broderick, Kate E

2017-05-15

Respiratory syncytial virus (RSV) is a massive medical burden in infants, children and the elderly worldwide, and an effective, safe RSV vaccine remains an unmet need. Here we assess a novel vaccination strategy based on the intradermal delivery of a SynCon® DNA-based vaccine encoding engineered RSV-F antigen using a surface electroporation device (SEP) to target epidermal cells, in clinically relevant experimental models. We demonstrate the ability of this strategy to elicit robust immune responses. Importantly we demonstrate complete resistance to pulmonary infection at a single low dose of vaccine in the cotton rat RSV/A challenge model. In contrast to the formalin-inactivated RSV (FI-RSV) vaccine, there was no enhanced lung inflammation upon virus challenge after DNA vaccination. In summary the data presented outline the pre-clinical development of a highly efficacious, tolerable and safe non-replicating vaccine delivery strategy. Copyright © 2017. Published by Elsevier Ltd.

Perceptions and experiences of childhood vaccination communication strategies among caregivers and health workers in Nigeria: A qualitative study

PubMed Central

Oyo-Ita, Angela; Glenton, Claire; Fretheim, Atle; Ames, Heather; Muloliwa, Artur; Kaufman, Jessica; Hill, Sophie; Cliff, Julie; Cartier, Yuri; Owoaje, Eme; Bosch-Capblanch, Xavier; Rada, Gabriel; Lewin, Simon

2017-01-01

Background Effective vaccination communication with parents is critical in efforts to overcome barriers to childhood vaccination, tackle vaccine hesitancy and improve vaccination coverage. Health workers should be able to provide information to parents and other caregivers and support them in reaching decisions about vaccinating their children. Limited information exists regarding the perceptions of caregivers and health workers on the vaccination communication strategies employed in Nigeria. This study, which forms part of the ‘Communicate to vaccinate’ (COMMVAC) project, aims to explore the perceptions and experiences of caregivers and health workers in Nigeria on vaccination communication strategies implemented in their settings. Methodology We conducted the study in two States: Bauchi in Northern Nigeria and Cross River in the south. We carried out observations (n = 40), in-depth interviews (n = 14) and focus group discussions (FGDs) (n = 12) amongst 14 purposively selected health workers, two community leaders and 84 caregivers in the two states. We transcribed data verbatim and analysed the data using a framework analysis approach. Results Caregivers were informed about vaccination activities through three main sources: health facilities (during health education sessions conducted at antenatal or immunization clinics); media outlets; and announcements (in churches/mosques, communities and markets). Caregivers reported that the information received was very useful. Their preferred sources of information included phone text messages, town announcers, media and church/mosque announcements. Some caregivers perceived the clinic environment, long waiting times and health worker attitudes as barriers to receiving vaccination information.When delivering communication interventions, health workers described issues tied to poor communication skills; poor motivation; and attitudes of community members, including vaccine resistance. Conclusion Communication about

Modelling Vaccination Strategies against Rift Valley Fever in Livestock in Kenya.

PubMed

Gachohi, John M; Njenga, M Kariuki; Kitala, Philip; Bett, Bernard

2016-12-01

The impacts of vaccination on the transmission of Rift Valley fever virus (RVFV) have not been evaluated. We have developed a RVFV transmission model comprising two hosts-cattle as a separate host and sheep and goats as one combined host (herein after referred to as sheep)-and two vectors-Aedes species (spp) and Culex spp-and used it to predict the impacts of: (1) reactive vaccination implemented at various levels of coverage at pre-determined time points, (2) targeted vaccination involving either of the two host species, and (3) a periodic vaccination implemented biannually or annually before an outbreak. The model comprises coupled vector and host modules where the dynamics of vectors and hosts are described using a system of difference equations. Vector populations are structured into egg, larva, pupa and adult stages and the latter stage is further categorized into three infection categories: susceptible, exposed and infectious mosquitoes. The survival rates of the immature stages (egg, larva and pupa) are dependent on rainfall densities extracted from the Tropical Rainfall Measuring Mission (TRMM) for a Rift Valley fever (RVF) endemic site in Kenya over a period of 1827 days. The host populations are structured into four age classes comprising young, weaners, yearlings and adults and four infection categories including susceptible, exposed, infectious, and immune categories. The model reproduces the 2006/2007 RVF outbreak reported in empirical surveys in the target area and other seasonal transmission events that are perceived to occur during the wet seasons. Mass reactive vaccination strategies greatly reduce the potential for a major outbreak. The results also suggest that the effectiveness of vaccination can be enhanced by increasing the vaccination coverage, targeting vaccination on cattle given that this species plays a major role in the transmission of the virus, and using both periodic and reactive vaccination strategies. Reactive vaccination can be

Health economic evaluation of vaccination strategies for the prevention of herpes zoster and postherpetic neuralgia in Germany.

PubMed

Ultsch, Bernhard; Weidemann, Felix; Reinhold, Thomas; Siedler, Anette; Krause, Gérard; Wichmann, Ole

2013-09-26

Herpes zoster (HZ) is a self-limiting painful skin rash affecting mostly individuals from 50 years of age. The main complication is postherpetic neuralgia (PHN), a long-lasting pain after rash has resolved. A HZ-vaccine has recently been licensed in Europe for individuals older than 50 years. To support an informed decision-making for a potential vaccination recommendation, we conducted a health economic evaluation to identify the most cost-effective vaccination strategy. We developed a static Markov-cohort model, which compared a vaccine-scenario with no vaccination. The cohort entering the model was 50 years of age, vaccinated at age 60, and stayed over life-time in the model. Transition probabilities were based on HZ/PHN-epidemiology and demographic data from Germany, as well as vaccine efficacy (VE) data from clinical trials. Costs for vaccination and HZ/PHN-treatment (in Euros; 2010), as well as outcomes were discounted equally with 3% p.a. We accounted results from both, payer and societal perspective. We calculated benefit-cost-ratio (BCR), number-needed-to-vaccinate (NNV), and incremental cost-effectiveness ratios (ICERs) for costs per HZ-case avoided, per PHN-case avoided, and per quality-adjusted life-year (QALY) gained. Different target age-groups were compared to identify the most cost-effective vaccination strategy. Base-case-analysis as well as structural, descriptive-, and probabilistic-sensitivity-analyses (DSA, PSA) were performed. When vaccinating 20% of a cohort of 1 million 50 year old individuals at the age of 60 years, approximately 20,000 HZ-cases will be avoided over life-time. The NNV to avoid one HZ (PHN)-case was 10 (144). However, with a BCR of 0.34 this vaccination-strategy did not save costs. The base-case-analysis yielded an ICER of 1,419 (20,809) Euros per avoided HZ (PHN)-case and 28,146 Euros per QALY gained. Vaccination at the age of 60 was identified in most (sensitivity) analyses to be the most cost-effective vaccination

Health economic evaluation of vaccination strategies for the prevention of herpes zoster and postherpetic neuralgia in Germany

PubMed Central

2013-01-01

Background Herpes zoster (HZ) is a self-limiting painful skin rash affecting mostly individuals from 50 years of age. The main complication is postherpetic neuralgia (PHN), a long-lasting pain after rash has resolved. A HZ-vaccine has recently been licensed in Europe for individuals older than 50 years. To support an informed decision-making for a potential vaccination recommendation, we conducted a health economic evaluation to identify the most cost-effective vaccination strategy. Methods We developed a static Markov-cohort model, which compared a vaccine-scenario with no vaccination. The cohort entering the model was 50 years of age, vaccinated at age 60, and stayed over life-time in the model. Transition probabilities were based on HZ/PHN-epidemiology and demographic data from Germany, as well as vaccine efficacy (VE) data from clinical trials. Costs for vaccination and HZ/PHN-treatment (in Euros; 2010), as well as outcomes were discounted equally with 3% p.a. We accounted results from both, payer and societal perspective. We calculated benefit-cost-ratio (BCR), number-needed-to-vaccinate (NNV), and incremental cost-effectiveness ratios (ICERs) for costs per HZ-case avoided, per PHN-case avoided, and per quality-adjusted life-year (QALY) gained. Different target age-groups were compared to identify the most cost-effective vaccination strategy. Base-case-analysis as well as structural, descriptive-, and probabilistic-sensitivity-analyses (DSA, PSA) were performed. Results When vaccinating 20% of a cohort of 1 million 50 year old individuals at the age of 60 years, approximately 20,000 HZ-cases will be avoided over life-time. The NNV to avoid one HZ (PHN)-case was 10 (144). However, with a BCR of 0.34 this vaccination-strategy did not save costs. The base-case-analysis yielded an ICER of 1,419 (20,809) Euros per avoided HZ (PHN)-case and 28,146 Euros per QALY gained. Vaccination at the age of 60 was identified in most (sensitivity) analyses to be the most cost

Therapeutic HPV vaccines.

PubMed

Hancock, Gemma; Hellner, Karin; Dorrell, Lucy

2018-02-01

High-risk human papillomavirus (HPV) infection is known to be a necessary factor for cervical and anogenital malignancies. Cervical cancers account for over a quarter of a million deaths annually. Despite the availability of prophylactic vaccines, HPV infections remain extremely common worldwide. Furthermore, these vaccines are ineffective at clearing pre-existing infections and associated preinvasive lesions. As cervical dysplasia can regress spontaneously, a therapeutic HPV vaccine that boosts host immunity could have a significant impact on the morbidity and mortality associated with HPV. Therapeutic vaccines differ from prophylactic vaccines in that they are aimed at generating cell-mediated immunity rather than neutralising antibodies. This review will cover various therapeutic vaccine strategies in development for the treatment of HPV-associated lesions and cancers. Copyright © 2017 Elsevier Ltd. All rights reserved.

A cross sectional survey of attitudes, awareness and uptake of the parental pertussis booster vaccine as part of a cocooning strategy, Victoria, Australia

PubMed Central

2013-01-01

Background The Victorian Government Department of Health funded a diphtheria, tetanus and acellular pertussis vaccine for parents of infants from June 2009 to June 2012 as part of a cocooning strategy for the control of pertussis. The aim of this study was to assess parents’ attitudes and awareness of the vaccination program, and to estimate vaccine uptake. Methods A cross-sectional survey of 253 families with a child born in the first quarter of 2010 residing within five metropolitan and four rural local government areas in Victoria was conducted. Univariate analyses were performed to describe the relationship between demographic variables, knowledge and awareness of the disease, the vaccine program and vaccine uptake. Multivariate analyses examining predictors for awareness of the vaccine program and for the uptake of vaccination were also conducted. Results One hundred and five families were surveyed (response rate 43%). Of these, 93% indicated that they had heard of ‘pertussis’ or ‘whooping cough’ and 75% of mothers and 69% of fathers were aware the pertussis vaccine was available and funded for new parents. Overall, 70% of mothers and 53% of fathers were vaccinated following their child’s birth, with metropolitan fathers less likely to be vaccinated as rural fathers (RR = 0.6, p = 0.002). Being a younger mother (p = 0.02) or father (p = 0.047), and being an Australian-born father (RR = 1.9, p = 0.03) were found to predict uptake of the vaccine in parents. Conclusion Parents indicated a reasonable level of knowledge of pertussis and a willingness to be vaccinated to protect their child. However, vaccine uptake estimates indicated further opportunity for program improvement. Future cocooning strategies would benefit from specifically targeting fathers and metropolitan maternity hospitals to increase vaccine uptake. Wider promotion of the availability of vaccine providers may increase uptake to maximise the success of cocooning

Vaccination strategies for future influenza pandemics: a severity-based cost effectiveness analysis

PubMed Central

2013-01-01

Background A critical issue in planning pandemic influenza mitigation strategies is the delay between the arrival of the pandemic in a community and the availability of an effective vaccine. The likely scenario, born out in the 2009 pandemic, is that a newly emerged influenza pandemic will have spread to most parts of the world before a vaccine matched to the pandemic strain is produced. For a severe pandemic, additional rapidly activated intervention measures will be required if high mortality rates are to be avoided. Methods A simulation modelling study was conducted to examine the effectiveness and cost effectiveness of plausible combinations of social distancing, antiviral and vaccination interventions, assuming a delay of 6-months between arrival of an influenza pandemic and first availability of a vaccine. Three different pandemic scenarios were examined; mild, moderate and extreme, based on estimates of transmissibility and pathogenicity of the 2009, 1957 and 1918 influenza pandemics respectively. A range of different durations of social distancing were examined, and the sensitivity of the results to variation in the vaccination delay, ranging from 2 to 6 months, was analysed. Results Vaccination-only strategies were not cost effective for any pandemic scenario, saving few lives and incurring substantial vaccination costs. Vaccination coupled with long duration social distancing, antiviral treatment and antiviral prophylaxis was cost effective for moderate pandemics and extreme pandemics, where it saved lives while simultaneously reducing the total pandemic cost. Combined social distancing and antiviral interventions without vaccination were significantly less effective, since without vaccination a resurgence in case numbers occurred as soon as social distancing interventions were relaxed. When social distancing interventions were continued until at least the start of the vaccination campaign, attack rates and total costs were significantly lower, and

Vaccination strategies for future influenza pandemics: a severity-based cost effectiveness analysis.

PubMed

Kelso, Joel K; Halder, Nilimesh; Milne, George J

2013-02-11

A critical issue in planning pandemic influenza mitigation strategies is the delay between the arrival of the pandemic in a community and the availability of an effective vaccine. The likely scenario, born out in the 2009 pandemic, is that a newly emerged influenza pandemic will have spread to most parts of the world before a vaccine matched to the pandemic strain is produced. For a severe pandemic, additional rapidly activated intervention measures will be required if high mortality rates are to be avoided. A simulation modelling study was conducted to examine the effectiveness and cost effectiveness of plausible combinations of social distancing, antiviral and vaccination interventions, assuming a delay of 6-months between arrival of an influenza pandemic and first availability of a vaccine. Three different pandemic scenarios were examined; mild, moderate and extreme, based on estimates of transmissibility and pathogenicity of the 2009, 1957 and 1918 influenza pandemics respectively. A range of different durations of social distancing were examined, and the sensitivity of the results to variation in the vaccination delay, ranging from 2 to 6 months, was analysed. Vaccination-only strategies were not cost effective for any pandemic scenario, saving few lives and incurring substantial vaccination costs. Vaccination coupled with long duration social distancing, antiviral treatment and antiviral prophylaxis was cost effective for moderate pandemics and extreme pandemics, where it saved lives while simultaneously reducing the total pandemic cost. Combined social distancing and antiviral interventions without vaccination were significantly less effective, since without vaccination a resurgence in case numbers occurred as soon as social distancing interventions were relaxed. When social distancing interventions were continued until at least the start of the vaccination campaign, attack rates and total costs were significantly lower, and increased rates of vaccination

Farmers' perception of the role of veterinary surgeons in vaccination strategies on British dairy farms.

PubMed

Richens, I F; Hobson-West, P; Brennan, M L; Lowton, R; Kaler, J; Wapenaar, W

2015-11-07

There is limited research investigating the motivators and barriers to vaccinating dairy cattle. Veterinary surgeons have been identified as important sources of information for farmers making vaccination and disease control decisions, as well as being farmers' preferred vaccine suppliers. Vets' perception of their own role and communication style can be at odds with farmers' reported preferences. The objective of this study was to investigate how dairy farmers perceived the role of vets in implementing vaccination strategies on their farm. Semi-structured interviews were conducted with 24 dairy farmers from across Britain. The data were analysed using thematic analysis. Analysis revealed that farmers perceive vets to have an important role in facilitating decision-making in all aspects of vaccination, including the aspects of vaccine distribution and advice on implementation. This important role is acknowledged by farmers who have regular veterinary contact, but also farmers with solely emergency veterinary contact. Given this finding, future work should investigate the attitudes of vets towards vaccination and how they perceive their role. Combining this knowledge will enable optimisation of vaccination strategies on British dairy farms. British Veterinary Association.

[Immunization strategy of hepatitis B vaccine among adults in China: evidence based-medicine and consideration].

PubMed

Xu, A Q; Zhang, L

2016-06-01

With the effective control of hepatitis B infection among children, the adults especial the young ones become the main population for new hepatitis B virus infection. Now the adults receive hepatitis B vaccination voluntarily and at their own expense in China and the coverage is low. The high immunogenicity of hepatitis B vaccine has been proven among healthy adults. Although the safety of hepatitis B vaccination has been documented among high-risk population such as HIV-infected people, injecting drug users and patients with chronic hepatitis disease, their antibody seroconversion rate after hepatitis B vaccination is lower than the healthy adults. Hepatitis B vaccination is recommended to population at high risk officially in many countries and some effects have been achieved. It is urgent to improve the strategy of hepatitis B vaccination among adults to fasten the control of hepatitis B in China, along with the researches about the long-term efficacy of hepatitis B vaccine among adults, the immunogenicity of hepatitis B vaccination among high-risk adults and the economical evaluation about different adult immunization strategy of hepatitis B.

A game dynamic model for delayer strategies in vaccinating behaviour for pediatric infectious diseases.

PubMed

Bhattacharyya, Samit; Bauch, C T

2010-12-07

Several studies have found that some parents delay the age at which their children receive pediatric vaccines due to perception of higher vaccine risk at the recommended age of vaccination. This has been particularly apparently during the Measles-Mumps-Rubella scare in the United Kingdom. Under a voluntary vaccination policy, vaccine coverage in certain age groups is a potentially complex interplay between vaccinating behaviour, disease dynamics, and age-specific risk factors. Here, we construct an age-structured game dynamic model, where individuals decide whether to vaccinate according to imitation dynamics depending on age-dependent disease prevalence and perceived risk of vaccination. Individuals may be timely vaccinators, delayers, or non-vaccinators. The model exhibits multiple equilibria and a broad range of possible dynamics. For certain parameter regimes, the proportion of timely vaccinators and delayers oscillate in an anti-phase fashion in response to oscillations in infection prevalence. Under an exogenous change to the perceived risk of vaccination as might occur during a vaccine scare, the model can also capture an increase in delayer strategists similar in magnitude to that observed during the Measles-Mumps-Rubella vaccine scare in the United Kingdom. Our model also shows that number of delayers steadily increases with increasing severity of the scare, whereas it saturates to specific value with increases in duration of the scare. Finally, by comparing the model dynamics with and without the option of a delayer strategy, we show that adding a third delayer strategy can have a stabilizing effect on model dynamics. In an era where individual choice--rather than accessibility--is becoming an increasingly important determinant of vaccine uptake, more infectious disease models may need to use game theory or related techniques to determine vaccine uptake. Copyright © 2010 Elsevier Ltd. All rights reserved.

Effectiveness and Cost-Effectiveness of Expanded Antiviral Prophylaxis and Adjuvanted Vaccination Strategies for the Next Influenza Pandemic

PubMed Central

Khazeni, Nayer; Hutton, David W; Garber, Alan M; Owens, Douglas K

2011-01-01

Background The pandemic potential of the influenza A (H5N1) virus is among the greatest public health concerns of the 21st century. Objective To determine the effectiveness and cost-effectiveness of alternative pandemic mitigation and response strategies. Design Compartmental epidemic model in conjunction with a Markov model of disease progression. Data Sources Literature and expert opinion. Target Population Residents of a U.S. metropolitan city. Time Horizon Lifetime. Perspective Societal. Interventions One mitigation strategy used non-pharmaceutical interventions, vaccination, and antiviral pharmacotherapy in quantities similar to those available currently in the U.S. stockpile. The second and third strategies used expanded supplies of either antivirals (expanded antiviral prophylaxis strategy) or adjuvanted vaccine (expanded vaccination strategy) in addition to non-pharmaceutical interventions. Outcome Measures Infections and deaths averted, costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness. Results of Base Case Analysis The stockpiled strategy averted 44% of infections and deaths, gaining 258,342 QALYs at $8,907 per QALY gained relative to no intervention. Expanded antiviral prophylaxis delayed the pandemic, averting 48% of infections and deaths, and gaining 282,329 QALYs, with a less favorable cost-effectiveness ratio than adjuvanted vaccination. Adjuvanted vaccination was the most effective strategy and was cost-effective, averting 68% of infections and deaths, and gaining 404,030 QALYs at $10,844 per QALY gained relative to stockpiled strategy. Results of Sensitivity Analysis Over a wide range of assumptions, the incremental cost-effectiveness ratio of the expanded adjuvanted vaccination strategy was less than $50,000 per QALY gained. Limitations Large groups and frequent contacts may spread the virus more rapidly. The model is not designed to target interventions to specific groups. Conclusions Expanded adjuvanted vaccination

Vaccine antigen production in transgenic plants: strategies, gene constructs and perspectives.

PubMed

Sala, Francesco; Manuela Rigano, M; Barbante, Alessandra; Basso, Barbara; Walmsley, Amanda M; Castiglione, Stefano

2003-01-30

Stable integration of a gene into the plant nuclear or chloroplast genome can transform higher plants (e.g. tobacco, potato, tomato, banana) into bioreactors for the production of subunit vaccines for oral or parental administration. This can also be achieved by using recombinant plant viruses as transient expression vectors in infected plants. The use of plant-derived vaccines may overcome some of the major problems encountered with traditional vaccination against infectious diseases, autoimmune diseases and tumours. They also offer a convenient tool against the threat of bio-terrorism. State of the art, experimental strategies, safety and perspectives are discussed in this article.

Don't aim too high: Avoiding shoulder injury related to vaccine administration.

PubMed

Cross, Gail B; Moghaddas, Jason; Buttery, Jim; Ayoub, Sally; Korman, Tony M

2016-05-01

Shoulder injury related to vaccine administration (SIRVA) is a previously described phenomenon that is the result of improper vaccine delivery. Appropriate injection technique for administration of intramuscular vaccinations can reduce the risk of shoulder injury. In this article, we describe the cases of two patients who developed SIRVA. A literature review was conducted to find and describe other cases of shoulder injury that developed post-vaccination. SIRVA has previously been described in the world literature. Seventeen cases in women and five cases in men were found. Pain and reduction in the range of movement within a few hours of vaccination were cardinal signs of a shoulder injury. This included injuries to the soft tissues of the shoulder as well as injuries to bone and joint. SIRVA can be avoided with correct vaccination technique as described.

[Approaches and problems in vaccine development against leishmaniasis].

PubMed

Allahverdiyev, Adil; Bağirova, Melahat; Cakir Koç, Rabia; Oztel, Olga Nehir; Elçıçek, Serhat; Ateş, Sezen Canım; Karaca, Tuğçe Deniz

2010-01-01

Leishmaniasis is a major public health problem of the world and Turkey. Recently there has been increasing interest in vaccine studies among strategies for control of leishmaniasis. Recently the increase of interest in vaccine studies among leishmaniasis control strategies makes the subject more up to date. So the aim of this review is to present information about recent vaccine studies, problems and new strategies for vaccine development studies. There are 3 generations of vaccine against leishmaniasis. First-generation vaccines are killed or live attenuated parasites; second-generation vaccines are recombinant or native antigens and live genetically modified parasites (knock out and suicidal cassettes), third generation vaccines are DNA vaccines. Also vector salivary proteins, dendritic cells and non-pathogenic L. tarentolae have been used as vaccine candidates. However there is still no effective vaccine against leishmaniasis. Since polymer conjugates considerably increase immunogenicity, polymer based vaccine studies have gained importance in recent years. However, there has not been such a study for an antileishmanial vaccine yet. LPG, surface antigen of Leishmania promastigotes, and polymer conjugates may be promising in antileishmanial vaccine studies so we are carrying out a TUBITAK Project on this subject which has been given the number, 1085170SBAG-4007.

Current therapeutic vaccination and immunotherapy strategies for HPV-related diseases

PubMed Central

Skeate, Joseph G.; Woodham, Andrew W.; Einstein, Mark H.; Da Silva, Diane M.; Kast, W. Martin

2016-01-01

ABSTRACT Carcinomas of the anogenital tract, in particular cervical cancer, remains one of the most common cancers in women, and represent the most frequent gynecological malignancies and the fourth leading cause of cancer death in women worldwide. Human papillomavirus (HPV)-induced lesions are immunologically distinct in that they express viral antigens, which are necessary to maintain the cancerous phenotype. The causal relationship between HPV infection and anogenital cancer has prompted substantial interest in the development of therapeutic vaccines against high-risk HPV types targeting the viral oncoproteins E6 and E7. This review will focus on the most recent clinical trials for immunotherapies for mucosal HPV-induced lesions as well as emerging therapeutic strategies that have been tested in pre-clinical models for HPV-induced diseases. Progress in peptide- and protein-based vaccines, DNA-based vaccines, viral/bacterial vector-based vaccines, immune checkpoint inhibition, immune response modifiers, and adoptive cell therapy for HPV will be discussed. PMID:26835746

Current therapeutic vaccination and immunotherapy strategies for HPV-related diseases.

PubMed

Skeate, Joseph G; Woodham, Andrew W; Einstein, Mark H; Da Silva, Diane M; Kast, W Martin

2016-06-02

Carcinomas of the anogenital tract, in particular cervical cancer, remains one of the most common cancers in women, and represent the most frequent gynecological malignancies and the fourth leading cause of cancer death in women worldwide. Human papillomavirus (HPV)-induced lesions are immunologically distinct in that they express viral antigens, which are necessary to maintain the cancerous phenotype. The causal relationship between HPV infection and anogenital cancer has prompted substantial interest in the development of therapeutic vaccines against high-risk HPV types targeting the viral oncoproteins E6 and E7. This review will focus on the most recent clinical trials for immunotherapies for mucosal HPV-induced lesions as well as emerging therapeutic strategies that have been tested in pre-clinical models for HPV-induced diseases. Progress in peptide- and protein-based vaccines, DNA-based vaccines, viral/bacterial vector-based vaccines, immune checkpoint inhibition, immune response modifiers, and adoptive cell therapy for HPV will be discussed.

The Italian alliance for vaccination strategies: Facebook as a learning tool for preventive medicine and public health.

PubMed

La Torre, Giuseppe; Miccoli, Silvia; Ricciardi, Walter

2014-01-01

The Italian Alliance of vaccination strategies project was born with the aim of informing healthcare workers and the general population about vaccination through Facebook. The evaluation of the account has been carried out using 3 indicators: friend membership, numbers of "I like," and amount of "share" of contents for type of news and for day of the week. The survey was performed on 743 users. Institutional events were the most popular type of news; the day of the week in which users were most likely to be attracted by links was Friday. Press releases were the communication form most shared by users. Social media marketing carries the advantages of low cost, rapid transmission and user interaction.

Exosomes Enter Vaccine Development: Strategies Meeting Global Challenges of Emerging Infections.

PubMed

Jungbauer, Alois

2018-04-01

New approaches for vaccination must be developed in order to meet the grand challenges for emerging infectious diseases. Exosomes now enter vaccine development and these are strategies are meeting these global challenges, as demonstrated by Anticoli et al., in this issue of Biotechnology Journal. Using exosome vaccines has been now been demonstrated in vivo for several viruses such as Ebola Virus VP24, VP40, and NP, Influenza Virus NP, Crimean-Congo Hemorrhagic Fever NP, West Nile Virus NS3, and Hepatitis C Virus NS3. Now this technology must be tested in clinics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Influenza Vaccination Strategies: Comparing Inactivated and Live Attenuated Influenza Vaccines

PubMed Central

Sridhar, Saranya; Brokstad, Karl A.; Cox, Rebecca J.

2015-01-01

Influenza is a major respiratory pathogen causing annual outbreaks and occasional pandemics. Influenza vaccination is the major method of prophylaxis. Currently annual influenza vaccination is recommended for groups at high risk of complications from influenza infection such as pregnant women, young children, people with underlying disease and the elderly, along with occupational groups such a healthcare workers and farm workers. There are two main types of vaccines available: the parenteral inactivated influenza vaccine and the intranasal live attenuated influenza vaccine. The inactivated vaccines are licensed from 6 months of age and have been used for more than 50 years with a good safety profile. Inactivated vaccines are standardized according to the presence of the viral major surface glycoprotein hemagglutinin and protection is mediated by the induction of vaccine strain specific antibody responses. In contrast, the live attenuated vaccines are licensed in Europe for children from 2–17 years of age and provide a multifaceted immune response with local and systemic antibody and T cell responses but with no clear correlate of protection. Here we discuss the immunological immune responses elicited by the two vaccines and discuss future work to better define correlates of protection. PMID:26343192

[A cost-effectiveness analysis on universal infant rotavirus vaccination strategy in China].

PubMed

Sun, S L; Gao, Y Q; Yin, J; Zhuang, G H

2016-02-01

To evaluate the cost-effectiveness of current universal infant rotavirus vaccination strategy, in China. Through constructing decision tree-Markov model, we simulated rotavirus diarrhea associated cost and health outcome on those newborns in 2012 regarding different vaccination programs as: group with no vaccination, Rotavirus vaccination group and Rotateq vaccination group, respectively. We determined the optimal program, based on the comparison between incremental cost-effectiveness ratio (ICER) and China' s 2012 per capital gross domestic product (GDP). Compared with non-vaccination group, the Rotavirus vaccination and Rotateq vaccination groups had to pay 3 760 Yuan and 7 578 Yuan (both less than 2012 GDP per capital) to avert one disability adjusted life years (DALY) loss, respectively. RESULTS from sensitivity analysis indicated that both results were robust. Compared with Rotavirus vaccination program, the Rotateq vaccination program had to pay extra 81 068 Yuan (between 1 and 3 times GDP per capital) to avert one DALY loss. Data from the sensitivity analysis indicated that the result was not robust. From the perspective of health economics, both two-dose Rotarix vaccine and three-dose' s Rotateq vaccine programs were highly cost-effective, when compared to the non-vaccination program. It was appropriate to integrate rotavirus vaccine into the routine immunization program. Considering the large amount of extra cost that had to spend on Rotateq vaccination program, results from the sensitivity analysis showed that it was not robust. Rotateq vaccine required one more dose than the Rotarix vaccine, to be effective. However, it appeared more difficult to practice, suggesting that it was better to choose the Rotarix vaccine, at current stage.

Persistent parasites and immunologic memory in cutaneous leishmaniasis: implications for vaccine designs and vaccination strategies.

PubMed

Okwor, Ifeoma; Uzonna, Jude

2008-01-01

Despite a plethora of publications on the murine model of cutaneous leishmaniasis and their contribution to our understanding of the factors that regulate the development of CD4+ T cell immunity in vivo, there is still no effective vaccine against the human disease. While recovery from natural or experimental infection with Leishmania major, the causative agent of human cutaneous leishmaniasis, results in persistence of parasites at the primary infection site and the development of long-lasting immunity to reinfection, vaccination with killed parasites or recombinant proteins induces only short-term protection. The reasons for the difference in protective immunity following recovery from live infection and vaccination with heat-killed parasites are not known. This may in part be related to persistence of live parasites following healing of primary cutaneous lesions, because complete clearance of parasites leads to rapid loss of infection-induced immunity. Recent reports indicate that in addition to persistent parasites, IL-10-producing natural regulatory T cells may also play critical roles in the maintenance and loss of infection-induced immunity. This review focuses on current understanding of the factors that regulate the development, maintenance and loss of anti-Leishmania memory responses and highlights the role of persistent parasites and regulatory T cells in this process. Understanding these factors is crucial for designing effective vaccines and vaccination strategies against cutaneous leishmaniasis.

A novel vaccination strategy mediating the induction of lung-resident memory CD8 T cells confers heterosubtypic immunity against future pandemic influenza virus

PubMed Central

Lee, Yu-Na; Lee, Young-Tae; Kim, Min-Chul; Gewirtz, Andrew T.; Kang, Sang-Moo

2016-01-01

The currently used vaccine strategy to combat influenza A virus (IAV) aims to provide highly specific immunity to circulating seasonal IAV strains. However, the outbreak of 2009 influenza pandemic highlights the danger in this strategy. Here, we tested the hypothesis that universal vaccination that offers broader but weaker protection would result in cross protective T-cell responses after primary IAV infection, which would subsequently provide protective immunity against future pandemic strains. Specifically, we used tandem repeat M2e epitopes on virus-like particles (M2e5x VLP) that induced heterosubtypic immunity by eliciting antibodies to a conserved M2e epitope. M2e5x VLP was found to be superior to strain-specific current split vaccine in conferring heterosubtypic cross protection and in equipping the host with cross-protective lung-resident nucleoprotein-specific memory CD8+ T cell responses to a subsequent secondary infection with a new pandemic potential strain. Immune correlates for subsequent heterosubtypic immunity by M2e5x VLP vaccination were found to be virus-specific CD8+ T cells secreting IFN-γ and expressing lung-resident memory phenotypic markers CD69+ and CD103+ as well as M2e antibodies. Hence, vaccination with M2e5x VLP may be developable as a new strategy to combat future pandemic outbreaks. PMID:26864033

Optimal H1N1 vaccination strategies based on self-interest versus group interest.

PubMed

Shim, Eunha; Meyers, Lauren Ancel; Galvani, Alison P

2011-02-25

Influenza vaccination is vital for reducing H1N1 infection-mediated morbidity and mortality. To reduce transmission and achieve herd immunity during the initial 2009-2010 pandemic season, the US Centers for Disease Control and Prevention (CDC) recommended that initial priority for H1N1 vaccines be given to individuals under age 25, as these individuals are more likely to spread influenza than older adults. However, due to significant delay in vaccine delivery for the H1N1 influenza pandemic, a large fraction of population was exposed to the H1N1 virus and thereby obtained immunity prior to the wide availability of vaccines. This exposure affects the spread of the disease and needs to be considered when prioritizing vaccine distribution. To determine optimal H1N1 vaccine distributions based on individual self-interest versus population interest, we constructed a game theoretical age-structured model of influenza transmission and considered the impact of delayed vaccination. Our results indicate that if individuals decide to vaccinate according to self-interest, the resulting optimal vaccination strategy would prioritize adults of age 25 to 49 followed by either preschool-age children before the pandemic peak or older adults (age 50-64) at the pandemic peak. In contrast, the vaccine allocation strategy that is optimal for the population as a whole would prioritize individuals of ages 5 to 64 to curb a growing pandemic regardless of the timing of the vaccination program. Our results indicate that for a delayed vaccine distribution, the priorities that are optimal at a population level do not align with those that are optimal according to individual self-interest. Moreover, the discordance between the optimal vaccine distributions based on individual self-interest and those based on population interest is even more pronounced when vaccine availability is delayed. To determine optimal vaccine allocation for pandemic influenza, public health agencies need to consider

Strategies toward vaccines against Burkholderia mallei and Burkholderia pseudomallei.

PubMed

Bondi, Sara K; Goldberg, Joanna B

2008-11-01

Burkholderia mallei and Burkholderia pseudomallei are Gram-negative, rod-shaped bacteria, and are the causative agents of the diseases glanders and melioidosis, respectively. These bacteria have been recognized as important pathogens for over 100 years, yet a relative dearth of available information exists regarding their virulence determinants and immunopathology. Infection with either of these bacteria presents with nonspecific symptoms and can be either acute or chronic, impeding rapid diagnosis. The lack of a vaccine for either bacterium also makes them potential candidates for bioweaponization. Together with their high rate of infectivity via aerosols and resistance to many common antibiotics, both bacteria have been classified as category B priority pathogens by the US NIH and US CDC, which has spurred a dramatic increase in interest in these microorganisms. Attempts have been made to develop vaccines for these infections, which would not only benefit military personnel, a group most likely to be targeted in an intentional release, but also individuals who may come in contact with glanders-infected animals or live in areas where melioidosis is endemic. This review highlights some recent attempts of vaccine development for these infections and the strategies used to improve the efficacy of vaccine approaches.

New Horizons in the Development of Novel Needle-Free Immunization Strategies to Increase Vaccination Efficacy.

PubMed

Schulze, Kai; Ebensen, Thomas; Riese, Peggy; Prochnow, Blair; Lehr, Claus-Michael; Guzmán, Carlos A

2016-01-01

The young twenty-first century has already brought several medical advances, such as a functional artificial human liver created from stem cells, improved antiviral (e.g., against HIV) and cancer (e.g., against breast cancer) therapies, interventions controlling cardiovascular diseases, and development of new and optimized vaccines (e.g., HPV vaccine). However, despite this substantial progress and the achievements of the last century, humans still suffer considerably from diseases, especially from infectious diseases. Thus, almost one-fourth of all deaths worldwide are caused directly or indirectly by infectious agents. Although vaccination has led to the control of many diseases, including smallpox, diphtheria, and tetanus, emerging diseases are still not completely contained. Furthermore, pathogens such as Bordetella pertussis undergo alterations making adaptation of the respective vaccine necessary. Moreover, insufficient implementation of vaccination campaigns leads to re-emergence of diseases which were believed to be already under control (e.g., poliomyelitis). Therefore, novel vaccination strategies need to be developed in order to meet the current challenges including lack of compliance, safety issues, and logistic constraints. In this context, mucosal and transdermal approaches constitute promising noninvasive vaccination strategies able to match these demands.

Photochemical Internalization of Peptide Antigens Provides a Novel Strategy to Realize Therapeutic Cancer Vaccination

PubMed Central

Haug, Markus; Brede, Gaute; Håkerud, Monika; Nedberg, Anne Grete; Gederaas, Odrun A.; Flo, Trude H.; Edwards, Victoria T.; Selbo, Pål K.; Høgset, Anders; Halaas, Øyvind

2018-01-01

Effective priming and activation of tumor-specific CD8+ cytotoxic T lymphocytes (CTLs) is crucial for realizing the potential of therapeutic cancer vaccination. This requires cytosolic antigens that feed into the MHC class I presentation pathway, which is not efficiently achieved with most current vaccination technologies. Photochemical internalization (PCI) provides an emerging technology to route endocytosed material to the cytosol of cells, based on light-induced disruption of endosomal membranes using a photosensitizing compound. Here, we investigated the potential of PCI as a novel, minimally invasive, and well-tolerated vaccination technology to induce priming of cancer-specific CTL responses to peptide antigens. We show that PCI effectively promotes delivery of peptide antigens to the cytosol of antigen-presenting cells (APCs) in vitro. This resulted in a 30-fold increase in MHC class I/peptide complex formation and surface presentation, and a subsequent 30- to 100-fold more efficient activation of antigen-specific CTLs compared to using the peptide alone. The effect was found to be highly dependent on the dose of the PCI treatment, where optimal doses promoted maturation of immature dendritic cells, thus also providing an adjuvant effect. The effect of PCI was confirmed in vivo by the successful induction of antigen-specific CTL responses to cancer antigens in C57BL/6 mice following intradermal peptide vaccination using PCI technology. We thus show new and strong evidence that PCI technology holds great potential as a novel strategy for improving the outcome of peptide vaccines aimed at triggering cancer-specific CD8+ CTL responses. PMID:29670624

Evolving T-cell vaccine strategies for HIV, the virus with a thousand faces

DOE Office of Scientific and Technical Information (OSTI.GOV)

Korber, Bette

HIV's rapid global spread and the human suffering it has left in its wake have made AIDS a global heath priority for the 25 years since its discovery. Yet its capacity to rapidly evolve has made combating this virus a tremendous challenge. The obstacles to creating an effective HIV vaccine are formidable, but there are advances in the field on many fronts, in terms of novel vectors, adjuvants, and antigen design strategies. SIV live attenuated vaccine models are able to confer protection against heterologous challenge, and this continues to provide opportunities to explore the biological underpinnings of a protective effectmore » (9). More indirect, but equally important, is new understanding regarding the biology of acute infection (43), the role of immune response in long-term non-progression (6,62, 81), and defining characteristics of broadly neutralizing antibodies (4). In this review we will focus on summarizing strategies directed towards a single issue, that of contending with HIV variation in terms of designing aT-cell vaccine. The strategies that prove most effective in this area can ultimately be combined with the best strategies under development in other areas, with the hope of ultimately converging on a viable vaccine candidate. Only two large HIV vaccine efficacy trials have been completed and both have failed to prevent infection or confer a benefit to infected individual (23,34), but there is ample reason to continue our efforts. A historic breakthrough came in 1996, when it was realized that although the virus could escape from a single antiretroviral (ARV) therapy, it could be thwarted by a combination of medications that simultaneously targeted different parts of the virus (HAART) (38). This revelation came after 15 years of research, thought, and clinical testing; to enable that vital progress the research and clinical communities had to first define and understand, then develop a strategy to counter, the remarkable evolutionary potential of

Fowl adenovirus serotype 4: Epidemiology, pathogenesis, diagnostic detection, and vaccine strategies.

PubMed

Li, P H; Zheng, P P; Zhang, T F; Wen, G Y; Shao, H B; Luo, Q P

2017-08-01

Fowl adenovirus (FAdV) serotype-4 is highly pathogenic for chickens, especially for broilers aged 3 to 5 wk, and it has emerged as one of the foremost causes of economic losses to the poultry industry in the last 30 years. The liver is a major target organ of FAdV-4 infections, and virus-infected chickens usually show symptoms of hydropericardium syndrome. The virus is very contagious, and it is spread both vertically and horizontally. It can be isolated from infected liver homogenates and detected by several laboratory diagnostic methods (including an agar gel immunodiffusion test, indirect immunofluorescence assays, counterimmunoelectrophoresis, enzyme-linked immunosorbent assays, restriction endonuclease analyses, polymerase chain reaction (PCR), real-time PCR, and high-resolution melting-curve analyses). Although inactivated vaccines have been deployed widely to control the disease, attenuated live vaccines and subunit vaccines also have been developed, and they are more attractive vaccine candidates. This article provides a comprehensive review of FAdV-4, including its epidemiology, pathogenesis, diagnostic detection, and vaccine strategies. © 2017 Poultry Science Association Inc.

Strategy of topical vaccination with nanoparticles

NASA Astrophysics Data System (ADS)

Jung, Sascha; Patzelt, Alexa; Otberg, Nina; Thiede, Gisela; Sterry, Wolfram; Lademann, Juergen

2009-03-01

Liposomes in the nanosize range have been recognized as a versatile drug delivery system of both hydrophilic and lipophilic molecules. In order to develop a liposome-based topical vaccination strategy, five different types of liposomes were tested as a putative vaccine delivery system on pig ear skin. The investigated liposomes mainly varied in size, lipid composition, and surface charge. Using hydrophilic and hydrophobic fluorescent dyes as model drugs, penetration behavior was studied by means of confocal laser scanning microscopy of intact skin and histological sections, respectively. Follicular penetration of the liposomes was measured in comparison to a standard, nonliposomal formulation at different time points. Dependent on time but independent of their different characters, the liposomes showed a significantly higher penetration depth into the hair follicles compared to the standard formulation. The standard formulation reached a relative penetration depth of 30% of the full hair follicle length after seven days, whereas amphoteric and cationic liposomes had reached ~70%. Penetration depth of negatively charged liposomes did not exceed 50% of the total follicle length. The fluorescence dyes were mainly detected in the hair follicle; only a small amount of dye was found in the upper parts of the epidermis.

Strategy of topical vaccination with nanoparticles.

PubMed

Jung, Sascha; Patzelt, Alexa; Otberg, Nina; Thiede, Gisela; Sterry, Wolfram; Lademann, Juergen

2009-01-01

Liposomes in the nanosize range have been recognized as a versatile drug delivery system of both hydrophilic and lipophilic molecules. In order to develop a liposome-based topical vaccination strategy, five different types of liposomes were tested as a putative vaccine delivery system on pig ear skin. The investigated liposomes mainly varied in size, lipid composition, and surface charge. Using hydrophilic and hydrophobic fluorescent dyes as model drugs, penetration behavior was studied by means of confocal laser scanning microscopy of intact skin and histological sections, respectively. Follicular penetration of the liposomes was measured in comparison to a standard, nonliposomal formulation at different time points. Dependent on time but independent of their different characters, the liposomes showed a significantly higher penetration depth into the hair follicles compared to the standard formulation. The standard formulation reached a relative penetration depth of 30% of the full hair follicle length after seven days, whereas amphoteric and cationic liposomes had reached approximately 70%. Penetration depth of negatively charged liposomes did not exceed 50% of the total follicle length. The fluorescence dyes were mainly detected in the hair follicle; only a small amount of dye was found in the upper parts of the epidermis.

Finding optimal vaccination strategies under parameter uncertainty using stochastic programming.

PubMed

Tanner, Matthew W; Sattenspiel, Lisa; Ntaimo, Lewis

2008-10-01

We present a stochastic programming framework for finding the optimal vaccination policy for controlling infectious disease epidemics under parameter uncertainty. Stochastic programming is a popular framework for including the effects of parameter uncertainty in a mathematical optimization model. The problem is initially formulated to find the minimum cost vaccination policy under a chance-constraint. The chance-constraint requires that the probability that R(*) vaccination reproduction number. We also show how to formulate the problem in two additional cases: (a) finding the optimal vaccination policy when vaccine supply is limited and (b) a cost-benefit scenario. The class of epidemic models for which this method can be used is described and we present an example formulation for which the resulting problem is a mixed-integer program. A short numerical example based on plausible parameter values and distributions is given to illustrate how including parameter uncertainty improves the robustness of the optimal strategy at the cost of higher coverage of the population. Results derived from a stochastic programming analysis can also help to guide decisions about how much effort and resources to focus on collecting data needed to provide better estimates of key parameters.

Pricing strategies for combination pediatric vaccines based on the lowest overall cost formulary.

PubMed

Behzad, Banafsheh; Jacobson, Sheldon H; Sewell, Edward C

2012-10-01

This paper analyzes pricing strategies for US pediatric combination vaccines by comparing the lowest overall cost formularies (i.e., formularies that have the lowest overall cost). Three pharmaceutical companies compete pairwise over the sale of monovalent and combination vaccines. Particular emphasis is placed on examining the price of Sanofi Pasteur's DTaP-IPV/HIb under different conditions. The main contribution of the paper is to provide the lowest overall cost formularies for different prices of DTaP-IPV/HIb and other Sanofi Pasteur vaccines. The resulting analysis shows that DTaP-IPV/HIb could have been more competitively priced compared with the combination vaccine DTaP-HepB-IPV, for federal contract prices in 2009, 2010 and 2011. This study also proposes the lowest overall cost formularies when shortages of monovalent vaccines occur.

Understanding vaccine hesitancy around vaccines and vaccination from a global perspective: a systematic review of published literature, 2007-2012.

PubMed

Larson, Heidi J; Jarrett, Caitlin; Eckersberger, Elisabeth; Smith, David M D; Paterson, Pauline

2014-04-17

Vaccine "hesitancy" is an emerging term in the literature and discourse on vaccine decision-making and determinants of vaccine acceptance. It recognizes a continuum between the domains of vaccine acceptance and vaccine refusal and de-polarizes previous characterization of individuals and groups as either anti-vaccine or pro-vaccine. The primary aims of this systematic review are to: 1) identify research on vaccine hesitancy; 2) identify determinants of vaccine hesitancy in different settings including its context-specific causes, its expression and its impact; and 3) inform the development of a model for assessing determinants of vaccine hesitancy in different settings as proposed by the Strategic Advisory Group of Experts Working Group (SAGE WG) for dealing with vaccine hesitancy. A broad search strategy, built to capture multiple dimensions of public trust, confidence and hesitancy around vaccines, was applied across multiple databases. Peer-reviewed studies were selected for inclusion if they focused on childhood vaccines [≤ 7 years of age], used multivariate analyses, and were published between January 2007 and November 2012. Our results show a variety of factors as being associated with vaccine hesitancy but they do not allow for a complete classification and confirmation of their independent and relative strength of influence. Determinants of vaccine hesitancy are complex and context-specific - varying across time, place and vaccines. Copyright © 2014 Elsevier Ltd. All rights reserved.

Informing rubella vaccination strategies in East Java, Indonesia through transmission modelling.

PubMed

Wu, Yue; Wood, James; Khandaker, Gulam; Waddington, Claire; Snelling, Thomas

2016-11-04

An estimated 110,000 babies are born with congenital rubella syndrome (CRS) worldwide annually; a significant proportion of cases occur in Southeast Asia. Rubella vaccine programs have led to successful control of rubella and CRS, and even the elimination of disease in many countries. However, if vaccination is poorly implemented it might increase the number of women reaching childbearing age who remain susceptible to rubella and thereby paradoxically increase CRS. We used an age-structured transmission model to compare seven alternative vaccine strategies for their impact on reducing CRS disease burden in East Java, a setting which is yet to implement a rubella vaccine program. We also investigated the robustness of model predictions to variation in vaccine coverage and other key epidemiological factors. Without rubella vaccination, approximately 700 babies are estimated to be born with CRS in East Java every year at an incidence of 0.77 per 1000live births. This incidence could be reduced to 0.0045 per 1000 live births associated with 99.9% annual reduction in rubella infections after 20 years if the existing two doses of measles vaccine are substituted with two doses of measles plus rubella combination vaccine with the same coverage (87.8% of 9-month-old infants and 80% of 6-year-old children). By comparison a single dose of rubella vaccine will take longer to reduce the burden of rubella and CRS and will be less robust to lower vaccine coverage. While the findings of this study should be informative for settings similar to East Java, the conclusions are dependent on vaccine coverage which would need consideration before applying to all of Indonesia and elsewhere in Asia. Copyright © 2016 Elsevier Ltd. All rights reserved.

Strategies toward vaccines against Burkholderia mallei and Burkholderia pseudomallei

PubMed Central

Bondi, Sara K; Goldberg, Joanna B

2009-01-01

Burkholderia mallei and Burkholderia pseudomallei are Gram-negative, rod-shaped bacteria, and are the causative agents of the diseases glanders and melioidosis, respectively. These bacteria have been recognized as important pathogens for over 100 years, yet a relative dearth of available information exists regarding their virulence determinants and immunopathology. Infection with either of these bacteria presents with nonspecific symptoms and can be either acute or chronic, impeding rapid diagnosis. The lack of a vaccine for either bacterium also makes them potential candidates for bioweaponization. Together with their high rate of infectivity via aerosols and resistance to many common antibiotics, both bacteria have been classified as category B priority pathogens by the US NIH and US CDC, which has spurred a dramatic increase in interest in these microorganisms. Attempts have been made to develop vaccines for these infections, which would not only benefit military personnel, a group most likely to be targeted in an intentional release, but also individuals who may come in contact with glanders-infected animals or live in areas where melioidosis is endemic. This review highlights some recent attempts of vaccine development for these infections and the strategies used to improve the efficacy of vaccine approaches. PMID:18980539

Vaccine hesitancy and healthcare providers.

PubMed

Paterson, Pauline; Meurice, François; Stanberry, Lawrence R; Glismann, Steffen; Rosenthal, Susan L; Larson, Heidi J

2016-12-20

While most people vaccinate according to the recommended schedule, this success is challenged by individuals and groups who delay or refuse vaccines. The aim of this article is to review studies on vaccine hesitancy among healthcare providers (HCPs), and the influences of their own vaccine confidence and vaccination behaviour on their vaccination recommendations to others. The search strategy was developed in Medline and then adapted across several multidisciplinary mainstream databases including Embase Classic & Embase, and PschInfo. All foreign language articles were included if the abstract was available in English. A total of 185 articles were included in the literature review. 66% studied the vaccine hesitancy among HCPs, 17% analysed concerns, attitudes and/or behaviour of HCPs towards vaccinating others, and 9% were about evaluating intervention(s). Overall, knowledge about particular vaccines, their efficacy and safety, helped to build HCPs own confidence in vaccines and their willingness to recommend vaccines to others. The importance of societal endorsement and support from colleagues was also reported. In the face of emerging vaccine hesitancy, HCPs still remain the most trusted advisor and influencer of vaccination decisions. The capacity and confidence of HCPs, though, are stretched as they are faced with time constraints, increased workload and limited resources, and often have inadequate information or training support to address parents' questions. Overall, HCPs need more support to manage the quickly evolving vaccine environment as well as changing public, especially those who are reluctant or refuse vaccination. Some recommended strategies included strengthening trust between HCPs, health authorities and policymakers, through more shared involvement in the establishment of vaccine recommendations. Copyright © 2016. Published by Elsevier Ltd.

Assessing the cost-effectiveness of different measles vaccination strategies for children in the Democratic Republic of Congo.

PubMed

Doshi, Reena H; Eckhoff, Philip; Cheng, Alvan; Hoff, Nicole A; Mukadi, Patrick; Shidi, Calixte; Gerber, Sue; Wemakoy, Emile Okitolonda; Muyembe-Tafum, Jean-Jacques; Kominski, Gerald F; Rimoin, Anne W

2017-10-27

One of the goals of the Global Measles and Rubella Strategic Plan is the reduction in global measles mortality, with high measles vaccination coverage as one of its core components. While measles mortality has been reduced more than 79%, the disease remains a major cause of childhood vaccine preventable disease burden globally. Measles immunization requires a two-dose schedule and only countries with strong, stable immunization programs can rely on routine services to deliver the second dose. In the Democratic Republic of Congo (DRC), weak health infrastructure and lack of provision of the second dose of measles vaccine necessitates the use of supplementary immunization activities (SIAs) to administer the second dose. We modeled three vaccination strategies using an age-structured SIR (Susceptible-Infectious-Recovered) model to simulate natural measles dynamics along with the effect of immunization. We compared the cost-effectiveness of two different strategies for the second dose of Measles Containing Vaccine (MCV) to one dose of MCV through routine immunization services over a 15-year time period for a hypothetical birth cohort of 3 million children. Compared to strategy 1 (MCV1 only), strategy 2 (MCV2 by SIA) would prevent a total of 5,808,750 measles cases, 156,836 measles-related deaths and save U.S. $199 million. Compared to strategy 1, strategy 3 (MCV2 by RI) would prevent a total of 13,232,250 measles cases, 166,475 measles-related deaths and save U.S. $408 million. Vaccination recommendations should be tailored to each country, offering a framework where countries can adapt to local epidemiological and economical circumstances in the context of other health priorities. Our results reflect the synergistic effect of two doses of MCV and demonstrate that the most cost-effective approach to measles vaccination in DRC is to incorporate the second dose of MCV in the RI schedule provided that high enough coverage can be achieved. Published by Elsevier Ltd.

Advances in Therapeutic Cancer Vaccines.

PubMed

Wong, Karrie K; Li, WeiWei Aileen; Mooney, David J; Dranoff, Glenn

2016-01-01

Therapeutic cancer vaccines aim to induce durable antitumor immunity that is capable of systemic protection against tumor recurrence or metastatic disease. Many approaches to therapeutic cancer vaccines have been explored, with varying levels of success. However, with the exception of Sipuleucel T, an ex vivo dendritic cell vaccine for prostate cancer, no therapeutic cancer vaccine has yet shown clinical efficacy in phase 3 randomized trials. Though disappointing, lessons learned from these studies have suggested new strategies to improve cancer vaccines. The clinical success of checkpoint blockade has underscored the role of peripheral tolerance mechanisms in limiting vaccine responses and highlighted the potential for combination therapies. Recent advances in transcriptome sequencing, computational modeling, and material engineering further suggest new opportunities to intensify cancer vaccines. This review will discuss the major approaches to therapeutic cancer vaccination and explore recent advances that inform the design of the next generation of cancer vaccines. © 2016 Elsevier Inc. All rights reserved.

The personal touch: strategies toward personalized vaccines and predicting immune responses to them

PubMed Central

Kennedy, Richard B.; Ovsyannikova, Inna G.; Lambert, Nathaniel D.; Haralambieva, Iana H.; Poland, Gregory A.

2014-01-01

The impact of vaccines on public health and well-being has been profound. Smallpox has been eradicated, polio is nearing eradication, and multiple diseases have been eliminated from certain areas of the world. Unfortunately, we now face diseases such as: hepatitis C, malaria, or tuberculosis, as well as new and re-emerging pathogens for which lack effective vaccines. Empirical approaches to vaccine development have been successful in the past, but may not be up to the current infectious disease challenges facing us. New, directed approaches to vaccine design, development, and testing need to be developed. Ideally these approaches will capitalize on cutting-edge technologies, advanced analytical and modeling strategies, and up-to-date knowledge of both pathogen and host. These approaches will pay particular attention to the causes of inter-individual variation in vaccine response in order to develop new vaccines tailored to the unique needs of individuals and communities within the population. PMID:24702429

Rice-based mucosal vaccine as a global strategy for cold-chain- and needle-free vaccination

PubMed Central

Nochi, Tomonori; Takagi, Hidenori; Yuki, Yoshikazu; Yang, Lijun; Masumura, Takehiro; Mejima, Mio; Nakanishi, Ushio; Matsumura, Akiko; Uozumi, Akihiro; Hiroi, Takachika; Morita, Shigeto; Tanaka, Kunisuke; Takaiwa, Fumio; Kiyono, Hiroshi

2007-01-01

Capable of inducing antigen-specific immune responses in both systemic and mucosal compartments without the use of syringe and needle, mucosal vaccination is considered ideal for the global control of infectious diseases. In this study, we developed a rice-based oral vaccine expressing cholera toxin B subunit (CTB) under the control of the endosperm-specific expression promoter 2.3-kb glutelin GluB-1 with codon usage optimization for expression in rice seed. An average of 30 μg of CTB per seed was stored in the protein bodies, which are storage organelles in rice. When mucosally fed, rice seeds expressing CTB were taken up by the M cells covering the Peyer's patches and induced CTB-specific serum IgG and mucosal IgA antibodies with neutralizing activity. When expressed in rice, CTB was protected from pepsin digestion in vitro. Rice-expressed CTB also remained stable and thus maintained immunogenicity at room temperature for >1.5 years, meaning that antigen-specific mucosal immune responses were induced at much lower doses than were necessary with purified recombinant CTB. Because they require neither refrigeration (cold-chain management) nor a needle, these rice-based mucosal vaccines offer a highly practical and cost-effective strategy for orally vaccinating large populations against mucosal infections, including those that may result from an act of bioterrorism. PMID:17573530

Universal Vaccines and Vaccine Platforms to Protect against Influenza Viruses in Humans and Agriculture

PubMed Central

Rajão, Daniela S.; Pérez, Daniel R.

2018-01-01

Influenza virus infections pose a significant threat to public health due to annual seasonal epidemics and occasional pandemics. Influenza is also associated with significant economic losses in animal production. The most effective way to prevent influenza infections is through vaccination. Current vaccine programs rely heavily on the vaccine's ability to stimulate neutralizing antibody responses to the hemagglutinin (HA) protein. One of the biggest challenges to an effective vaccination program lies on the fact that influenza viruses are ever-changing, leading to antigenic drift that results in escape from earlier immune responses. Efforts toward overcoming these challenges aim at improving the strength and/or breadth of the immune response. Novel vaccine technologies, the so-called universal vaccines, focus on stimulating better cross-protection against many or all influenza strains. However, vaccine platforms or manufacturing technologies being tested to improve vaccine efficacy are heterogeneous between different species and/or either tailored for epidemic or pandemic influenza. Here, we discuss current vaccines to protect humans and animals against influenza, highlighting challenges faced to effective and uniform novel vaccination strategies and approaches. PMID:29467737

Jabs and barbs: ways to address misleading vaccination and immunisation information using currently available strategies.

PubMed

Wardle, Jon; Stewart, Cameron; Parker, Malcolm

2013-09-01

Misleading vaccination information undermines confidence in vaccination and may lead to reductions in the effectiveness of vaccination programs. A number of regulatory techniques can be employed to challenge the spread of false information, including health care complaints, therapeutic goods laws, consumer protection laws and professional discipline. This article examines three case studies involving the publication of anti-vaccination information by non-professionally aligned organisations, by non-registered health professionals, and by registered health professionals under the National Law. The article examines the effectiveness of different regulatory responses and makes suggestions for future strategies to deal with the publication of demonstrably false information regarding vaccination.

The cost-effectiveness of two strategies for vaccinating US veterans with hepatitis C virus infection against hepatitis A and hepatitis B viruses.

PubMed

Jakiche, Rita; Borrego, Matthew E; Raisch, Dennis W; Gupchup, Gireesh V; Pai, Manjunath A; Jakiche, Antoine

2007-01-01

Although hepatitis A and B vaccinations are recommended for patients with chronic hepatitis C virus (HCV), the ideal vaccination strategy has not been determined. Our objective was to model the cost-effectiveness of two strategies for vaccinating patients with HCV infection against hepatitis A (HAV) and hepatitis B (HBV) viruses. The strategies evaluated were: universal vaccination with the combined HAV and HBV vaccine, and selective vaccination based on immunity determined by blood testing. A decision tree model was constructed to compare the cost-effectiveness of the two vaccination strategies from the New Mexico Veterans Affairs Health Care System (NMVAHCS) perspective. A retrospective review of all HCV patients (2517 subjects) at the NMVAHCS was performed to extract prevalence of immunity to HAV and HBV, and prevalence of decompensated liver disease. Literature review was performed to obtain other probabilities for the model. Only direct medical costs were considered; the effectiveness measure was the number of patients immune to both HAV and HBV. Sensitivity analyses were performed to test robustness of the results to changes in input variables. All costs were in 2004 US dollars. The selective strategy was less costly but less effective, with a cost-effectiveness ratio of 105 dollars per patient immune to HAV and HBV. The universal strategy was more effective but more expensive with a cost-effectiveness ratio of 112 dollars per patient immune to HAV and HBV. Compared with the selective strategy, universal strategy was associated with an incremental cost-effectiveness (ICE) ratio of 154 dollars per additional patient immune to HAV and HBV. The universal strategy would become more cost-effective if 1) the cost of combined vaccine was reduced to less than 30.75 dollars (9.7% reduction), 2) the cost of HBV vaccine increased to greater than 34.50 dollars (25% increase), 3) the cost of blood tests for immunity increased to more than 25.25 dollars (23% increase), or

Strategies to increase influenza vaccination rates: outcomes of a nationwide cross-sectional survey of UK general practice

PubMed Central

Teare, M Dawn; Dexter, Matthew; Siriwardena, A Niroshan; Read, Robert C

2012-01-01

Objective To identify practice strategies associated with higher flu vaccination rates in primary care. Design Logistic regression analysis of data from a cross-sectional online questionnaire. Setting 795 general practices across England. Participants 569 practice managers, 335 nursing staff and 107 general practitioners. Primary outcome measures Flu vaccination rates achieved by each practice in different groups of at-risk patients. Results 7 independent factors associated with higher vaccine uptake were identified. Having a lead staff member for planning the flu campaign and producing a written report of practice performance predicted an 8% higher vaccination rate for at-risk patients aged <65 years (OR 1.37, 95% CI 1.10 to 1.71). These strategies, plus sending a personal invitation to all eligible patients and only stopping vaccination when Quality and Outcomes Framework targets are reached, predicted a 7% higher vaccination rate (OR 1.45, 95% CI 1.10 to 1.92) in patients aged ≥65 years. Using a lead member of staff for identifying eligible patients, with either a modified manufacturer's or in-house search programme for interrogating the practice IT system, independently predicted a 4% higher vaccination rate in patients aged ≥65 years (OR 1.22, 95% CI 1.06 to 1.41/OR 1.20, 95% CI 1.03 to 1.40). The provision of flu vaccine by midwives was associated with a 4% higher vaccination rate in pregnant women (OR 1.19, 95% CI 1.02 to 1.40). Conclusions Clear leadership, effective communication about performance and methods used to identify and contact eligible patients were independently associated with significantly higher rates of flu vaccination. Financial targets appear to incentivise practices to work harder to maximise seasonal influenza vaccine uptake. The strategies identified here could help primary care providers to substantially increase their seasonal flu vaccination rates towards or even above the Chief Medical Officer's targets. PMID:22581793

HIV-1 vaccine strategies utilizing viral vectors including antigen- displayed inoviral vectors.

PubMed

Hassapis, Kyriakos A; Kostrikis, Leondios G

2013-12-01

Antigen-presenting viral vectors have been extensively used as vehicles for the presentation of antigens to the immune system in numerous vaccine strategies. Particularly in HIV vaccine development efforts, two main viral vectors have been used as antigen carriers: (a) live attenuated vectors and (b) virus-like particles (VLPs); the former, although highly effective in animal studies, cannot be clinically tested in humans due to safety concerns and the latter have failed to induce broadly neutralizing anti-HIV antibodies. For more than two decades, Inoviruses (non-lytic bacterial phages) have also been utilized as antigen carriers in several vaccine studies. Inoviral vectors are important antigen-carriers in vaccine development due to their ability to present an antigen on their outer architecture in many copies and to their natural high immunogenicity. Numerous fundamental studies have been conducted, which have established the unique properties of antigen-displayed inoviral vectors in HIV vaccine efforts. The recent isolation of new, potent anti-HIV broadly neutralizing monoclonal antibodies provides a new momentum in this emerging technology.

Hepatitis B Screening and Vaccination Strategies for Newly Arrived Adult Canadian Immigrants and Refugees: A Cost-Effectiveness Analysis

PubMed Central

Rossi, Carmine; Schwartzman, Kevin; Oxlade, Olivia; Klein, Marina B.; Greenaway, Chris

2013-01-01

Background Immigrants have increased mortality from hepatocellular carcinoma as compared to the host populations, primarily due to undetected chronic hepatitis B virus (HBV) infection. Despite this, there are no systematic programs in most immigrant-receiving countries to screen for chronic HBV infection and immigrants are not routinely offered HBV vaccination outside of the universal childhood vaccination program. Methods and findings A cost-effective analysis was performed to compare four HBV screening and vaccination strategies with no intervention in a hypothetical cohort of newly-arriving adult Canadian immigrants. The strategies considered were a) universal vaccination, b) screening for prior immunity and vaccination, c) chronic HBV screening and treatment, and d) combined screening for chronic HBV and prior immunity, treatment and vaccination. The analysis was performed from a societal perspective, using a Markov model. Seroprevalence estimates, annual transition probabilities, health-care costs (in Canadian dollars), and utilities were obtained from the published literature. Acute HBV infection, mortality from chronic HBV, quality-adjusted life years (QALYs), and costs were modeled over the lifetime of the cohort of immigrants. Costs and QALYs were discounted at a rate of 3% per year. Screening for chronic HBV infection, and offering treatment if indicated, was found to be the most cost-effective intervention and was estimated to cost $40,880 per additional QALY gained, relative to no intervention. This strategy was most cost-effective for immigrants < 55 years of age and would cost < $50,000 per additional QALY gained for immigrants from areas where HBV seroprevalence is ≥ 3%. Strategies that included HBV vaccination were either prohibitively expensive or dominated by the chronic HBV screening strategy. Conclusions Screening for chronic HBV infection from regions where most Canadian immigrants originate, except for Latin America and the Middle East, was

Hepatitis B screening and vaccination strategies for newly arrived adult Canadian immigrants and refugees: a cost-effectiveness analysis.

PubMed

Rossi, Carmine; Schwartzman, Kevin; Oxlade, Olivia; Klein, Marina B; Greenaway, Chris

2013-01-01

Immigrants have increased mortality from hepatocellular carcinoma as compared to the host populations, primarily due to undetected chronic hepatitis B virus (HBV) infection. Despite this, there are no systematic programs in most immigrant-receiving countries to screen for chronic HBV infection and immigrants are not routinely offered HBV vaccination outside of the universal childhood vaccination program. A cost-effective analysis was performed to compare four HBV screening and vaccination strategies with no intervention in a hypothetical cohort of newly-arriving adult Canadian immigrants. The strategies considered were a) universal vaccination, b) screening for prior immunity and vaccination, c) chronic HBV screening and treatment, and d) combined screening for chronic HBV and prior immunity, treatment and vaccination. The analysis was performed from a societal perspective, using a Markov model. Seroprevalence estimates, annual transition probabilities, health-care costs (in Canadian dollars), and utilities were obtained from the published literature. Acute HBV infection, mortality from chronic HBV, quality-adjusted life years (QALYs), and costs were modeled over the lifetime of the cohort of immigrants. Costs and QALYs were discounted at a rate of 3% per year. Screening for chronic HBV infection, and offering treatment if indicated, was found to be the most cost-effective intervention and was estimated to cost $40,880 per additional QALY gained, relative to no intervention. This strategy was most cost-effective for immigrants < 55 years of age and would cost < $50,000 per additional QALY gained for immigrants from areas where HBV seroprevalence is ≥ 3%. Strategies that included HBV vaccination were either prohibitively expensive or dominated by the chronic HBV screening strategy. Screening for chronic HBV infection from regions where most Canadian immigrants originate, except for Latin America and the Middle East, was found to be reasonably cost-effective and

A novel method to value real options in health care: the case of a multicohort human papillomavirus vaccination strategy.

PubMed

Favato, Giampiero; Baio, Gianluca; Capone, Alessandro; Marcellusi, Andrea; Saverio Mennini, Francesco

2013-07-01

A large number of economic evaluations have already confirmed the cost-effectiveness of different human papillomavirus (HPV) vaccination strategies. Standard analyses might not capture the full economic value of novel vaccination programs because the cost-effectiveness paradigm fails to take into account the value of active management. Management decisions can be seen as real options, a term used to refer to the application of option pricing theory to the valuation of investments in nonfinancial assets in which much of the value is attributable to flexibility and learning over time. The aim of this article was to discuss the potential advantages shown by using the payoff method in the valuation of the cost-effectiveness of competing HPV immunization programs. This was the first study, to the best of our knowledge, to use the payoff method to determine the real option values of 4 different HPV vaccination strategies targeting female subjects aged 12, 15, 18, and 25 years. The payoff method derives the real option value from the triangular payoff distribution of the project's net present value, which is treated as a triangular fuzzy number. To inform the real option model, cost-effectiveness data were derived from an empirically calibrated Bayesian model designed to assess the cost-effectiveness of a multicohort HPV vaccination strategy in the context of the current cervical cancer screening program in Italy. A net health benefit approach was used to calculate the expected fuzzy net present value for each of the 4 vaccination strategies evaluated. Costs per quality-adjusted life-year gained seemed to be related to the number of cohorts targeted: a single cohort of girls aged 12 years (€10,955 [95% CI, -1,021 to 28,212]) revealed the lowest cost among the 4 alternative strategies evaluated. The real option valuation challenged the cost-effectiveness dominance of a single cohort of 12-year-old girls. The simultaneous vaccination of 2 cohorts of girls aged 12 and 15

Novel health economic evaluation of a vaccination strategy to prevent HPV-related diseases: the BEST study.

PubMed

Favato, Giampiero; Baio, Gianluca; Capone, Alessandro; Marcellusi, Andrea; Costa, Silvano; Garganese, Giorgia; Picardo, Mauro; Drummond, Mike; Jonsson, Bengt; Scambia, Giovanni; Zweifel, Peter; Mennini, Francesco S

2012-12-01

The development of human papillomavirus (HPV)-related diseases is not understood perfectly and uncertainties associated with commonly utilized probabilistic models must be considered. The study assessed the cost-effectiveness of a quadrivalent-based multicohort HPV vaccination strategy within a Bayesian framework. A full Bayesian multicohort Markov model was used, in which all unknown quantities were associated with suitable probability distributions reflecting the state of currently available knowledge. These distributions were informed by observed data or expert opinion. The model cycle lasted 1 year, whereas the follow-up time horizon was 90 years. Precancerous cervical lesions, cervical cancers, and anogenital warts were considered as outcomes. The base case scenario (2 cohorts of girls aged 12 and 15 y) and other multicohort vaccination strategies (additional cohorts aged 18 and 25 y) were cost-effective, with a discounted cost per quality-adjusted life-year gained that corresponded to €12,013, €13,232, and €15,890 for vaccination programs based on 2, 3, and 4 cohorts, respectively. With multicohort vaccination strategies, the reduction in the number of HPV-related events occurred earlier (range, 3.8-6.4 y) when compared with a single cohort. The analysis of the expected value of information showed that the results of the model were subject to limited uncertainty (cost per patient = €12.6). This methodological approach is designed to incorporate the uncertainty associated with HPV vaccination. Modeling the cost-effectiveness of a multicohort vaccination program with Bayesian statistics confirmed the value for money of quadrivalent-based HPV vaccination. The expected value of information gave the most appropriate and feasible representation of the true value of this program.

Serogroup C Neisseria meningitidis invasive infection: analysis of the possible vaccination strategies for a mass campaign.

PubMed

Chiappini, Elena; Venturini, Elisabetta; Bonsignori, Francesca; Galli, Luisa; de Martino, Maurizio

2010-11-01

The serogroup C meningococcal conjugate vaccine is available since 1999. In the absence of randomized controlled trials that support a specific schedule, each country has adopted different vaccination programmes. Hereby, we analyse positive and negative aspects of the different vaccination strategies. While waiting for the introduction of other antimeningococcal vaccines, covering also for the Group B meningococci, further studies on effectiveness of an optimal schedule to be adopted in European countries are needed. © 2010 The Author(s)/Journal Compilation © 2010 Foundation Acta Paediatrica.

A world without bacterial meningitis: how genomic epidemiology can inform vaccination strategy.

PubMed

Rodrigues, Charlene M C; Maiden, Martin C J

2018-01-01

Bacterial meningitis remains an important cause of global morbidity and mortality. Although effective vaccinations exist and are being increasingly used worldwide, bacterial diversity threatens their impact and the ultimate goal of eliminating the disease. Through genomic epidemiology, we can appreciate bacterial population structure and its consequences for transmission dynamics, virulence, antimicrobial resistance, and development of new vaccines. Here, we review what we have learned through genomic epidemiological studies, following the rapid implementation of whole genome sequencing that can help to optimise preventative strategies for bacterial meningitis.

Cost-Effectiveness and Public Health Effect of Influenza Vaccine Strategies for U.S. Elderly Adults.

PubMed

Raviotta, Jonathan M; Smith, Kenneth J; DePasse, Jay; Brown, Shawn T; Shim, Eunha; Nowalk, Mary Patricia; Zimmerman, Richard K

2016-10-01

To compare the cost-effectiveness of four influenza vaccines available in the United States for persons aged 65 and older: trivalent inactivated influenza vaccine (IIV3), quadrivalent inactivated influenza vaccine (IIV4), a more-expensive high-dose IIV3, and a newly approved adjuvanted IIV3. Cost-effectiveness analysis using a Markov model and sensitivity analyses. A hypothetical influenza vaccination season modeled according to possible U.S. influenza vaccination policies. Hypothetical cohort of individuals aged 65 and older in the United States. Cost-effectiveness and public health benefits of available influenza vaccination strategies in U.S. elderly adults. IIV3 cost $3,690 per quality-adjusted life year (QALY) gained, IIV4 cost $20,939 more than IIV3 per QALY gained, and high-dose IIV3 cost $31,214 more per QALY than IIV4. The model projected 83,775 fewer influenza cases and 980 fewer deaths with high-dose IIV3 than with the next most-effective vaccine: IIV4. In a probabilistic sensitivity analysis, high-dose IIV3 was the favored strategy if willingness to pay is $25,000 or more per QALY gained. Adjuvanted IIV3 cost-effectiveness depends on its price and effectiveness (neither yet determined in the United States) but could be favored if its relative effectiveness is 15% greater than that of IIV3. From economic and public health standpoints, high-dose IIV3 for adults aged 65 years and older is likely to be favored over the other vaccines, based on currently available data. The cost-effectiveness of adjuvanted IIV3 should be reviewed after its effectiveness has been compared with that of other vaccines and its U.S. price is established. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

The impact of the web and social networks on vaccination. New challenges and opportunities offered to fight against vaccine hesitancy.

PubMed

Stahl, J-P; Cohen, R; Denis, F; Gaudelus, J; Martinot, A; Lery, T; Lepetit, H

2016-05-01

Vaccine hesitancy is a growing and threatening trend, increasing the risk of disease outbreaks and potentially defeating health authorities' strategies. We aimed to describe the significant role of social networks and the Internet on vaccine hesitancy, and more generally on vaccine attitudes and behaviors. Presentation and discussion of lessons learnt from: (i) the monitoring and analysis of web and social network contents on vaccination; (ii) the tracking of Google search terms used by web users; (iii) the analysis of Google search suggestions related to vaccination; (iv) results from the Vaccinoscopie(©) study, online annual surveys of representative samples of 6500 to 10,000 French mothers, monitoring vaccine behaviors and attitude of French parents as well as vaccination coverage of their children, since 2008; and (v) various studies published in the scientific literature. Social networks and the web play a major role in disseminating information about vaccination. They have modified the vaccination decision-making process and, more generally, the doctor/patient relationship. The Internet may fuel controversial issues related to vaccination and durably impact public opinion, but it may also provide new tools to fight against vaccine hesitancy. Vaccine hesitancy should be fought on the Internet battlefield, and for this purpose, communication strategies should take into account new threats and opportunities offered by the web and social networks. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Estimating the cost-effectiveness profile of a universal vaccination programme with a nine-valent HPV vaccine in Austria.

PubMed

Boiron, L; Joura, E; Largeron, N; Prager, B; Uhart, M

2016-04-16

HPV is a major cancer-causing factor in both sexes in the cervix, vulva, vagina, anus, penis, oropharynx as well as the causal factor in other diseases such as genital warts and recurrent respiratory papillomatis. In the context of the arrival of a nonavalent HPV vaccine (6/11/16/18/31/33/45/52/58), this analysis aims to estimate the public health impact and the incremental cost-effectiveness of a universal (girls and boys) vaccination program with a nonavalent HPV vaccine as compared to the current universal vaccination program with a quadrivalent HPV vaccine (6/11/16/18), in Austria. A dynamic transmission model including a wide range of health and cost outcomes related to cervical, anal, vulvar, vaginal diseases and genital warts was calibrated to Austrian epidemiological data. The clinical impact due to the 5 new types was included for cervical and anal diseases outcomes only. In the base case, a two-dose schedule, lifelong vaccine type-specific protection and a vaccination coverage rate of 60% and 40% for girls and boys respectively for the 9-year old cohorts were assumed. A cost-effectiveness threshold of €30,000/QALY-gained was considered. Universal vaccination with the nonavalent vaccine was shown to reduce the incidence of HPV16/18/31/33/45/52/58 -related cervical cancer by 92%, the related CIN2/3 cases by 96% and anal cancer by 83% and 76% respectively in females and males after 100 years, relative to 75%, 76%, 80% and 74% with the quadrivalent vaccine, respectively. Furthermore, the nonavalent vaccine was projected to prevent an additional 14,893 cases of CIN2/3 and 2544 cases of cervical cancer, over 100 years. Depending on the vaccine price, the strategy was shown to be from cost-saving to cost-effective. The present evaluation showed that vaccinating 60% of girls and 40% of boys aged 9 in Austria with a 9-valent vaccine will substantially reduce the incidence of cervical cancer, CIN and anal cancer compared to the existing strategy. The vaccination

Therapeutic Vaccines for Chronic Infections

NASA Astrophysics Data System (ADS)

Autran, Brigitte; Carcelain, Guislaine; Combadiere, Béhazine; Debre, Patrice

2004-07-01

Therapeutic vaccines aim to prevent severe complications of a chronic infection by reinforcing host defenses when some immune control, albeit insufficient, can already be demonstrated and when a conventional antimicrobial therapy either is not available or has limited efficacy. We focus on the rationale and challenges behind this still controversial strategy and provide examples from three major chronic infectious diseases-human immunodeficiency virus, hepatitis B virus, and human papillomavirus-for which the efficacy of therapeutic vaccines is currently being evaluated.

Young Hispanic Men and Human Papillomavirus Vaccination Choices.

PubMed

Thomas, Tami L; Stephens, Dionne P; Johnson-Mallard, Versie; Higgins, Melinda

2016-03-01

This exploratory descriptive study examined perceived vulnerabilities to human papillomavirus (HPV) and the correlation to factors influencing vaccine beliefs and vaccine decision making in young Hispanic males attending a large public urban university. Only 24% of participants believed that the HPV vaccine could prevent future problems, and 53% said they would not be vaccinated. The best predictors of HPV vaccination in young Hispanic men were agreement with doctor recommendations and belief in the vaccine's efficacy. Machismo cultural norms influence young Hispanic men's HPV-related decision making, their perceptions of the vaccine, and how they attitudinally act on what little HPV information they have access to. This study provides culturally relevant information for the development of targeted health education strategies aimed at increasing HPV vaccination in young Hispanic men. © The Author(s) 2014.

Budget-Impact Analysis of Alternative Herpes Zoster Vaccine Strategies: A U.S. HMO Perspective.

PubMed

Graham, Jonathan; Mauskopf, Josephine; Kawai, Kosuke; Johnson, Kelly D; Xu, Ruifeng; Acosta, Camilo J

2016-07-01

A herpes zoster vaccine has been approved by the FDA for use in prevention of herpes zoster in individuals who are aged 50 years or older. The Advisory Committee on Immunization Practices (ACIP) recommends vaccination only in individuals who are aged 60 years and older. To (a) estimate the overall budget and health impact of either the introduction of a new vaccination strategy (individuals over the age of 50 years vs. individuals over the age of 60 years) within a hypothetical health plan or simply an increase in coverage within the population aged 60 years and over and (b) discern what effect copayments and changes to copayments have on the health plan's budget. A decision-analytic economic model was developed to inform managed care decision makers of the potential effect on costs and outcomes associated with the use of the herpes zoster vaccine for prevention of herpes zoster (i.e., simple zoster or shingles). The model took a U.S. payer perspective. The number of eligible patients entering the model was estimated by considering the age distribution of the plan population and the percentage of patients contraindicated for vaccination (i.e., those who were immunocompromised or who had a history of anaphylactic/anaphylactoid reaction to gelatin, neomycin, or any other component of the vaccine). Eligible patients were vaccinated based on the projected uptake rates among the unvaccinated population in 2 possible vaccination scenarios: (1) a vaccination strategy in which only individuals over age 60 years can be vaccinated and (2) a vaccination strategy in which individuals over age 50 years can be vaccinated. Vaccination was assumed to reverse the age-related decline in immunity against zoster. The population vaccinated each year was estimated based on the uptake rates (percentage of the eligible unvaccinated that are vaccinated) required to reach a target annual coverage (percentage ever vaccinated). Patients could experience costs and outcomes related to

Comparing control strategies against foot-and-mouth disease: will vaccination be cost-effective in Denmark?

PubMed

Boklund, A; Halasa, T; Christiansen, L E; Enøe, C

2013-09-01

Recent outbreaks of foot-and-mouth disease (FMD) in Europe have highlighted the need for assessment of control strategies to optimise control of the spread of FMD. Our objectives were to assess the epidemiological and financial impact of simulated FMD outbreaks in Denmark and the effect of using ring depopulation or emergency vaccination to control these outbreaks. Two stochastic simulation models (InterSpreadPlus (ISP) and the modified Davis Animal Disease Simulation model (DTU-DADS)) were used to simulate the spread of FMD in Denmark using different control strategies. Each epidemic was initiated in one herd (index herd), and a total of 5000 index herds were used. Four types of control measures were investigated: (1) a basic scenario including depopulation of detected herds, 3 km protection and 10 km surveillance zones, movement tracing and a three-day national standstill, (2) the basic scenario plus depopulation in ring zones around detected herds (Depop), (3) the basic scenario plus protective vaccination within ring zones around detected herds, and (4) the basic scenario plus protective vaccination within ring zones around detected herds. Disease spread was simulated through direct animal movements, medium-risk contacts (veterinarians, artificial inseminators or milk controllers), low-risk contacts (animal feed and rendering trucks, technicians or visitors), market contacts, abattoir trucks, milk tanks, or local spread. The two simulation models showed different results in terms of the estimated numbers. However, the tendencies in terms of recommendations of strategies were similar for both models. Comparison of the different control strategies showed that, from an epidemiological point of view, protective vaccination would be preferable if the epidemic started in a cattle herd in an area with a high density of cattle, whereas if the epidemic started in an area with a low density of cattle or in other species, protective vaccination or depopulation would have

Optimal control analysis of Ebola disease with control strategies of quarantine and vaccination.

PubMed

Ahmad, Muhammad Dure; Usman, Muhammad; Khan, Adnan; Imran, Mudassar

2016-07-13

The 2014 Ebola epidemic is the largest in history, affecting multiple countries in West Africa. Some isolated cases were also observed in other regions of the world. In this paper, we introduce a deterministic SEIR type model with additional hospitalization, quarantine and vaccination components in order to understand the disease dynamics. Optimal control strategies, both in the case of hospitalization (with and without quarantine) and vaccination are used to predict the possible future outcome in terms of resource utilization for disease control and the effectiveness of vaccination on sick populations. Further, with the help of uncertainty and sensitivity analysis we also have identified the most sensitive parameters which effectively contribute to change the disease dynamics. We have performed mathematical analysis with numerical simulations and optimal control strategies on Ebola virus models. We used dynamical system tools with numerical simulations and optimal control strategies on our Ebola virus models. The original model, which allowed transmission of Ebola virus via human contact, was extended to include imperfect vaccination and quarantine. After the qualitative analysis of all three forms of Ebola model, numerical techniques, using MATLAB as a platform, were formulated and analyzed in detail. Our simulation results support the claims made in the qualitative section. Our model incorporates an important component of individuals with high risk level with exposure to disease, such as front line health care workers, family members of EVD patients and Individuals involved in burial of deceased EVD patients, rather than the general population in the affected areas. Our analysis suggests that in order for R 0 (i.e., the basic reproduction number) to be less than one, which is the basic requirement for the disease elimination, the transmission rate of isolated individuals should be less than one-fourth of that for non-isolated ones. Our analysis also predicts, we

Vaccine Efficacy of Inactivated, Chimeric Hemagglutinin H9/H5N2 Avian Influenza Virus and Its Suitability for the Marker Vaccine Strategy

PubMed Central

Kim, Se Mi; Kim, Young-Il; Park, Su-Jin; Kim, Eun-Ha; Kwon, Hyeok-il; Si, Young-Jae; Lee, In-Won; Song, Min-Suk

2017-01-01

ABSTRACT In order to produce a dually effective vaccine against H9 and H5 avian influenza viruses that aligns with the DIVA (differentiating infected from vaccinated animals) strategy, we generated a chimeric H9/H5N2 recombinant vaccine that expressed the whole HA1 region of A/CK/Korea/04163/04 (H9N2) and the HA2 region of recent highly pathogenic avian influenza (HPAI) A/MD/Korea/W452/14 (H5N8) viruses. The chimeric H9/H5N2 virus showed in vitro and in vivo growth properties and virulence that were similar to those of the low-pathogenic avian influenza (LPAI) H9 virus. An inactivated vaccine based on this chimeric virus induced serum neutralizing (SN) antibodies against both H9 and H5 viruses but induced cross-reactive hemagglutination inhibition (HI) antibody only against H9 viruses. Thus, this suggests its compatibility for use in the DIVA strategy against H5 strains. Furthermore, the chimeric H9/H5N2 recombinant vaccine protected immunized chickens against lethal challenge by HPAI H5N8 viruses and significantly attenuated virus shedding after infection by both H9N2 and HPAI H5N8 viruses. In mice, serological analyses confirmed that HA1- and HA2 stalk-specific antibody responses were induced by vaccination and that the DIVA principle could be employed through the use of an HI assay against H5 viruses. Furthermore, each HA1- and HA2 stalk-specific antibody response was sufficient to inhibit viral replication and protect the chimeric virus-immunized mice from lethal challenge with both mouse-adapted H9N2 and wild-type HPAI H5N1 viruses, although differences in vaccine efficacy against a homologous H9 virus (HA1 head domain immune-mediated protection) and a heterosubtypic H5 virus (HA2 stalk domain immune-mediated protection) were observed. Taken together, these results demonstrate that the novel chimeric H9/H5N2 recombinant virus is a low-pathogenic virus, and this chimeric vaccine is suitable for a DIVA vaccine with broad-spectrum neutralizing antibody against H5

Blocking pathogen transmission at the source: reservoir targeted OspA-based vaccines against Borrelia burgdorferi.

PubMed

Gomes-Solecki, Maria

2014-01-01

Control strategies are especially challenging for microbial diseases caused by pathogens that persist in wildlife reservoirs and use arthropod vectors to cycle amongst those species. One of the most relevant illnesses that pose a direct human health risk is Lyme disease; in the US, the Centers for Disease Control and Prevention recently revised the probable number of cases by 10-fold, to 300,000 cases per year. Caused by Borrelia burgdorferi, Lyme disease can affect the nervous system, joints and heart. No human vaccine is approved by the Food and Drug Administration. In addition to novel human vaccines, new strategies for prevention of Lyme disease consist of pest management interventions, vector-targeted vaccines and reservoir-targeted vaccines. However, even human vaccines can not prevent Lyme disease expansion into other geographical areas. The other strategies aim at reducing tick density and at disrupting the transmission of B. burgdorferi by targeting one or more key elements that maintain the enzootic cycle: the reservoir host and/or the tick vector. Here, I provide a brief overview of the application of an OspA-based wildlife reservoir targeted vaccine aimed at reducing transmission of B. burgdorferi and present it as a strategy for reducing Lyme disease risk to humans.

Blocking pathogen transmission at the source: reservoir targeted OspA-based vaccines against Borrelia burgdorferi

PubMed Central

Gomes-Solecki, Maria

2014-01-01

Control strategies are especially challenging for microbial diseases caused by pathogens that persist in wildlife reservoirs and use arthropod vectors to cycle amongst those species. One of the most relevant illnesses that pose a direct human health risk is Lyme disease; in the US, the Centers for Disease Control and Prevention recently revised the probable number of cases by 10-fold, to 300,000 cases per year. Caused by Borrelia burgdorferi, Lyme disease can affect the nervous system, joints and heart. No human vaccine is approved by the Food and Drug Administration. In addition to novel human vaccines, new strategies for prevention of Lyme disease consist of pest management interventions, vector-targeted vaccines and reservoir-targeted vaccines. However, even human vaccines can not prevent Lyme disease expansion into other geographical areas. The other strategies aim at reducing tick density and at disrupting the transmission of B. burgdorferi by targeting one or more key elements that maintain the enzootic cycle: the reservoir host and/or the tick vector. Here, I provide a brief overview of the application of an OspA-based wildlife reservoir targeted vaccine aimed at reducing transmission of B. burgdorferi and present it as a strategy for reducing Lyme disease risk to humans. PMID:25309883

Tricomponent Immunopotentiating System as a Novel Molecular Design Strategy for Malaria Vaccine Development ▿

PubMed Central

Miyata, Takeshi; Harakuni, Tetsuya; Tsuboi, Takafumi; Sattabongkot, Jetsumon; Ikehara, Ayumu; Tachibana, Mayumi; Torii, Motomi; Matsuzaki, Goro; Arakawa, Takeshi

2011-01-01

The creation of subunit vaccines to prevent malaria infection has been hampered by the intrinsically weak immunogenicity of the recombinant antigens. We have developed a novel strategy to increase immune responses by creating genetic fusion proteins to target specific antigen-presenting cells (APCs). The fusion complex was composed of three physically linked molecular entities: (i) a vaccine antigen, (ii) a multimeric α-helical coiled-coil core, and (iii) an APC-targeting ligand linked to the core via a flexible linker. The vaccine efficacy of the tricomponent complex was evaluated using an ookinete surface protein of Plasmodium vivax, Pvs25, and merozoite surface protein-1 of Plasmodium yoelii. Immunization of mice with the tricomponent complex induced a robust antibody response and conferred substantial levels of P. vivax transmission blockade as evaluated by a membrane feed assay, as well as protection from lethal P. yoelii infection. The observed effect was strongly dependent on the presence of all three components physically integrated as a fusion complex. This system, designated the tricomponent immunopotentiating system (TIPS), onto which any recombinant protein antigens or nonproteinaceous substances could be loaded, may be a promising strategy for devising subunit vaccines or adjuvants against various infectious diseases, including malaria. PMID:21807905

Young Hispanic Men and Human Papillomavirus Vaccination Choices

PubMed Central

Stephens, Dionne P.; Johnson-Mallard, Versie; Higgins, Melinda

2014-01-01

This exploratory descriptive study examined perceived vulnerabilities to HPV and the correlation to factors influencing vaccine beliefs and vaccine decision-making in young Hispanics males attending a large public urban university. Only 24% of participants believed the HPV vaccine could prevent future problems, and 53% said they would not be vaccinated. The best predictors of HPV vaccination in young Hispanic men were agreement with doctor recommendations and belief in the vaccine’s efficacy. Machismo cultural norms influence young Hispanic men’s HPV-related decision making, their perceptions of the vaccine, and how they attitudinally act upon what little HPV information they have access to. This study provides culturally relevant information for the development of targeted health education strategies aimed at increasing HPV vaccination in young Hispanic men. PMID:24841473

[Pertussis: Where do we stand 10years after the introduction of cocooning vaccination strategy in France?

PubMed

Beaufils, E; Dommergues, M-A; Gaillat, J; Guiso, N; Knezovic-Daniel, N; Pinquier, D; Riethmuller, D

2016-10-01

The goals of this article are to review the pertussis cocooning strategy, which has been recommended in France since 2004 to protect infants not yet vaccinated from becoming infected by vaccinating their immediate entourage, and to present room for improvement. The analysis of the literature between 2004 and 2015 shows that pertussis vaccine coverage in new parents is lower than 50% and that attempts that have already been implemented to increase it are effective. Pertussis vaccine coverage improvement requires all health actors to collaborate and be trained in informing and motivating parents to get vaccinated before, during and after pregnancy (the parents then will act as relays to their relatives); generalization in maternity wards of systematic checking of the vaccination card; extension to the midwives of the right to prescribe and administer pertussis vaccine to spouses; vaccination facilitation in maternity wards with the support of health organizations. Exchange and sharing of experiences between health care professionals are essential. Pregnancy is the ideal period to promote pertussis vaccination. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Optimized oral cholera vaccine distribution strategies to minimize disease incidence: A mixed integer programming model and analysis of a Bangladesh scenario.

PubMed

Smalley, Hannah K; Keskinocak, Pinar; Swann, Julie; Hinman, Alan

2015-11-17

In addition to improved sanitation, hygiene, and better access to safe water, oral cholera vaccines can help to control the spread of cholera in the short term. However, there is currently no systematic method for determining the best allocation of oral cholera vaccines to minimize disease incidence in a population where the disease is endemic and resources are limited. We present a mathematical model for optimally allocating vaccines in a region under varying levels of demographic and incidence data availability. The model addresses the questions of where, when, and how many doses of vaccines to send. Considering vaccine efficacies (which may vary based on age and the number of years since vaccination), we analyze distribution strategies which allocate vaccines over multiple years. Results indicate that, given appropriate surveillance data, targeting age groups and regions with the highest disease incidence should be the first priority, followed by other groups primarily in order of disease incidence, as this approach is the most life-saving and cost-effective. A lack of detailed incidence data results in distribution strategies which are not cost-effective and can lead to thousands more deaths from the disease. The mathematical model allows for what-if analysis for various vaccine distribution strategies by providing the ability to easily vary parameters such as numbers and sizes of regions and age groups, risk levels, vaccine price, vaccine efficacy, production capacity and budget. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of vaccines in the EU TB Vaccine Cluster using a guinea pig aerosol infection model of tuberculosis.

PubMed

Williams, Ann; Hatch, Graham J; Clark, Simon O; Gooch, Karen E; Hatch, Kim A; Hall, Graham A; Huygen, Kris; Ottenhoff, Tom H M; Franken, Kees L M C; Andersen, Peter; Doherty, T Mark; Kaufmann, Stefan H E; Grode, Leander; Seiler, Peter; Martin, Carlos; Gicquel, Brigitte; Cole, Stewart T; Brodin, Priscille; Pym, Alexander S; Dalemans, Wilfried; Cohen, Joe; Lobet, Yves; Goonetilleke, Nilu; McShane, Helen; Hill, Adrian; Parish, Tanya; Smith, Debbie; Stoker, Neil G; Lowrie, Douglas B; Källenius, Gunilla; Svenson, Stefan; Pawlowski, Andrzej; Blake, Karen; Marsh, Philip D

2005-01-01

The TB Vaccine Cluster project funded by the EU Fifth Framework programme aims to provide novel vaccines against tuberculosis that are suitable for evaluation in humans. This paper describes the studies of the protective efficacy of vaccines in a guinea pig aerosol-infection model of primary tuberculosis. The objective was to conduct comparative evaluations of vaccines that had previously demonstrated efficacy in other animal models. Groups of 6 guinea pigs were immunized with vaccines provided by the relevant EU Vaccine Cluster partners. Survival over 17 or 26 weeks was used as the principal measure of vaccine efficacy following aerosol challenge with H37Rv. Counts of mycobacteria in lungs and spleens, and histopathological changes in the lungs, were also used to provide evidence of protection. A total of 24 vaccines were evaluated in 4 experiments each of a different design. A heterologous prime-boost strategy of DNA and MVA, each expressing Ag85A and a fusion protein of ESAT-6 and Ag85B in adjuvant, protected the guinea pigs to the same extent as BCG. Genetically modified BCG vaccines and boosted BCG strategies also protected guinea pigs to the same extent as BCG but not statistically significantly better. A relatively high aerosol-challenge dose and evaluation over a protracted time post-challenge allowed superior protection over BCG to be demonstrated by BCG boosted with MVA and fowl pox vectors expressing Ag85A.

Casting off vaccine supply charity -- the pace quickens. CVI goal: quality vaccines for all children.

PubMed

1995-10-01

suggested for UNICEF's new targeting strategy and global vaccine fund for well-defined and specific needs. UNICEF is the main distributor of vaccines to developing countries and aims for program sustainability and distribution of the new vaccines.

Strategies in the development of vaccines to prevent infections with group A streptococcus

PubMed Central

Good, Michael F; Batzloff, Michael; Pandey, Manisha

2013-01-01

There has long been interest and demand for the development of a vaccine to prevent infections caused by the Gram-positive organism group A streptococcus. Despite numerous efforts utilizing advanced approaches such as genomics, proteomics and bio-informatics, there is currently no vaccine. Here we review various strategies employed to achieve this goal. We also discuss the approach that we have pursued, a non-host reactive, conformationally constrained minimal B cell epitope from within the C-repeat region of M-protein, and the potential limitations in moving forward. PMID:23863455

AIM-Monitoring: a component of the BLM assessment, inventory, and monitoring strategy

USDA-ARS?s Scientific Manuscript database

The “BLM Assessment, Inventory, and Monitoring Strategy for Integrated Renewable Resources Management” (AIM Strategy) was completed in 2011 in response to a request from the Office of Management and Budget. The strategy describes an approach for integrated, cross-program assessment, inventory, and m...

New strategies to improve the efficacy of colorectal cancer vaccines: from bench to bedside.

PubMed

Mocellin, Simone

2006-12-01

By exploiting a naturally occurring defense system, anticancer vaccination embodies an ideal non-toxic treatment capable of evoking tumor-specific immune responses that can ultimately recognize and kill colorectal cancer (CRC) cells. Despite the enormous theoretical potential of active specific immunotherapy, no vaccination regimen has achieved sufficient therapeutic efficacy necessary for clinical implementation. Nevertheless, several immunological advances have opened new avenues of research to decipher the biological code governing tumor immune responsiveness, and this is leading to the design of potentially more effective immunotherapeutic protocols. This review briefly summarizes the principles behind anti-CRC vaccination and describes the most promising immunological strategies that have been developed, which are expected to renew interest in this molecularly targeted anticancer approach.

Vaccines and IP Rights: A Multifaceted Relationship.

PubMed

Durell, Karen

2016-01-01

Just as there are many forms of vaccines and components to vaccines-particular compositions, delivery systems, components, and distribution networks-there are a variety of intellectual property (IP) protections applicable for vaccines. IP rights such as patent, copyright, trademarks, plant breeders' rights, and trade secrets may all be applicable to vaccines. Thus, discussion of IP rights and vaccines should not begin and end with the application of one IP right to a vaccine. The discussion should engage considerations of multiple IP rights applicable to a vaccine and how these can be utilized in an integrated manner in a strategy aimed at supporting the development and distribution of the vaccine. Such an approach to IP rights to vaccines allows for the integrated rights to be considered in light of the justifications for protecting vaccines with IP rights, as well as the issues relating to specific IP rights for vaccines, such as compulsory license regimes, available humanitarian purpose IP credits, etc. To view vaccines as the subject of multiple IP protections involves a refocusing, but the outcome can provide significant benefits for vaccine development and distribution.

Adolescent Attitudes toward Influenza Vaccination and Vaccine Uptake in a School-Based Influenza Vaccination Intervention: A Mediation Analysis

ERIC Educational Resources Information Center

Painter, Julia E.; Sales, Jessica M.; Pazol, Karen; Wingood, Gina M.; Windle, Michael; Orenstein, Walter A.; DiClemente, Ralph J.

2011-01-01

Background: School-based vaccination programs may provide an effective strategy to immunize adolescents against influenza. This study examined whether adolescent attitudes toward influenza vaccination mediated the relationship between receipt of a school-based influenza vaccination intervention and vaccine uptake. Methods: Participants were…

Dynamics of vaccination strategies via projected dynamical systems.

PubMed

Cojocaru, Monica-Gabriela; Bauch, Chris T; Johnston, Matthew D

2007-07-01

Previous game theoretical analyses of vaccinating behaviour have underscored the strategic interaction between individuals attempting to maximise their health states, in situations where an individual's health state depends upon the vaccination decisions of others due to the presence of herd immunity. Here, we extend such analyses by applying the theories of variational inequalities (VI) and projected dynamical systems (PDS) to vaccination games. A PDS provides a dynamics that gives the conditions for existence, uniqueness and stability properties of Nash equilibria. In this paper, it is used to analyse the dynamics of vaccinating behaviour in a population consisting of distinct social groups, where each group has different perceptions of vaccine and disease risks. In particular, we study populations with two groups, where the size of one group is strictly larger than the size of the other group (a majority/minority population). We find that a population with a vaccine-inclined majority group and a vaccine-averse minority group exhibits higher average vaccine coverage than the corresponding homogeneous population, when the vaccine is perceived as being risky relative to the disease. Our model also reproduces a feature of real populations: In certain parameter regimes, it is possible to have a majority group adopting high vaccination rates and simultaneously a vaccine-averse minority group adopting low vaccination rates. Moreover, we find that minority groups will tend to exhibit more extreme changes in vaccinating behaviour for a given change in risk perception, in comparison to majority groups. These results emphasise the important role played by social heterogeneity in vaccination behaviour, while also highlighting the valuable role that can be played by PDS and VI in mathematical epidemiology.

Tuberculosis vaccines: time to think about the next generation.

PubMed

Kaufmann, Stefan H E

2013-04-01

Efforts over the last 2 decades have led to a rich research and development pipeline of tuberculosis (TB) vaccines. Although none of the candidates has successfully completed the clinical trial pipeline, many are under advanced clinical assessment. These vaccines aim at prevention of active TB, with most of them being considered for preexposure with recent additions for postexposure or multistage administration. A few therapeutic vaccines are under clinical assessment, as well. Preexposure vaccination with the licensed TB vaccine BCG prevents severe forms of TB in children but not in adolescents and adults. The current vaccine pipeline does not include strategies which prevent or eliminate infection with the causative agent Mycobacterium tuberculosis (Mtb). Rather in a best-case scenario, they are quantitatively superior to BCG in preventing active TB over prolonged periods of time, ideally lifelong in the face of latent Mtb infection. Qualitatively superior vaccines should be capable of preventing or eliminating Mtb infection, in this way eliminating the risk of TB reactivation. The time is now ripe to exploit radically new strategies to achieve this goal. Copyright © 2013. Published by Elsevier Ltd.

Potential impact of spatially targeted adult tuberculosis vaccine in Gujarat, India

PubMed Central

Chatterjee, Susmita; Rao, Krishna D.; Dowdy, David W.

2016-01-01

Some of the most promising vaccines in the pipeline for tuberculosis (TB) target adolescents and adults. Unlike for childhood vaccines, high-coverage population-wide vaccination is significantly more challenging for adult vaccines. Here, we aimed to estimate the impact of vaccine delivery strategies that were targeted to high-incidence geographical ‘hotspots’ compared with randomly allocated vaccination. We developed a spatially explicit mathematical model of TB transmission that distinguished these hotspots from the general population. We evaluated the impact of targeted and untargeted vaccine delivery strategies in India—a country that bears more than 25% of global TB burden, and may be a potential early adopter of the vaccine. We collected TB notification data and conducted a demonstration study in the state of Gujarat to validate our estimates of heterogeneity in TB incidence. We then projected the impact of randomly vaccinating 8% of adults in a single mass campaign to a spatially targeted vaccination preferentially delivered to 80% of adults in the hotspots, with both strategies augmented by continuous adolescent vaccination. In consultation with vaccine developers, we considered a vaccine efficacy of 60%, and evaluated the population-level impact after 10 years of vaccination. Spatial heterogeneity in TB notification (per 100 000/year) was modest in Gujarat: 190 in the hotspots versus 125 in the remaining population. At this level of heterogeneity, the spatially targeted vaccination was projected to reduce TB incidence by 28% after 10 years, compared with a 24% reduction projected to achieve via untargeted vaccination—a 1.17-fold augmentation in the impact of vaccination by spatially targeting. The degree of the augmentation was robust to reasonable variation in natural history assumptions, but depended strongly on the extent of spatial heterogeneity and mixing between the hotspot and general population. Identifying high-incidence hotspots and

Vaccinating in disease-free regions: a vaccine model with application to yellow fever.

PubMed

Codeço, Claudia T; Luz, Paula M; Coelho, Flavio; Galvani, Alison P; Struchiner, Claudio

2007-12-22

Concerns regarding natural or induced emergence of infectious diseases have raised a debate on the pros and cons of pre-emptive vaccination of populations under uncertain risk. In the absence of immediate risk, ethical issues arise because even smaller risks associated with the vaccine are greater than the immediate disease risk (which is zero). The model proposed here seeks to formalize the vaccination decision process looking from the perspective of the susceptible individual, and results are shown in the context of the emergence of urban yellow fever in Brazil. The model decomposes the individual's choice about vaccinating or not into uncertain components. The choice is modelled as a function of (i) the risk of a vaccine adverse event, (ii) the risk of an outbreak and (iii) the probability of receiving the vaccine or escaping serious disease given an outbreak. Additionally, we explore how this decision varies as a function of mass vaccination strategies of varying efficiency. If disease is considered possible but unlikely (risk of outbreak less than 0.1), delay vaccination is a good strategy if a reasonably efficient campaign is expected. The advantage of waiting increases as the rate of transmission is reduced (low R0) suggesting that vector control programmes and emergency vaccination preparedness work together to favour this strategy. The opposing strategy, vaccinating pre-emptively, is favoured if the probability of yellow fever urbanization is high or if expected R0 is high and emergency action is expected to be slow. In summary, our model highlights the nonlinear dependence of an individual's best strategy on the preparedness of a response to a yellow fever outbreak or other emergent infectious disease.

A CRISPR/Cas9 and Cre/Lox system-based express vaccine development strategy against re-emerging Pseudorabies virus.

PubMed

Liang, Xun; Sun, Leqiang; Yu, Teng; Pan, Yongfei; Wang, Dongdong; Hu, Xueying; Fu, Zhenfang; He, Qigai; Cao, Gang

2016-01-18

Virus evolves rapidly to escape vaccine-induced immunity, posing a desperate demand for efficient vaccine development biotechnologies. Here we present an express vaccine development strategy based on CRISPR/Cas9 and Cre/Lox system against re-emerging Pseudorabies virus, which caused the recent devastating swine pseudorabies outbreak in China. By CRISPR/Cas9 system, the virulent genes of the newly isolated strain were simultaneously substituted by marker genes, which were subsequently excised using Cre/Lox system for vaccine safety concern. Notably, single cell FACS technology was applied to further promote virus purification efficiency. The combination of these state-of-art technologies greatly accelerated vaccine development. Finally, vaccination and challenge experiments proved this vaccine candidate's protective efficacy in pigs and the promise to control current pseudorabies outbreak. This is, to our knowledge, the first successful vaccine development based on gene edit technologies, demonstrating these technologies leap from laboratory to industry. It may pave the way for future express antiviral vaccine development.

A CRISPR/Cas9 and Cre/Lox system-based express vaccine development strategy against re-emerging Pseudorabies virus

PubMed Central

Liang, Xun; Sun, Leqiang; Yu, Teng; Pan, Yongfei; Wang, Dongdong; Hu, Xueying; Fu, Zhenfang; He, Qigai; Cao, Gang

2016-01-01

Virus evolves rapidly to escape vaccine-induced immunity, posing a desperate demand for efficient vaccine development biotechnologies. Here we present an express vaccine development strategy based on CRISPR/Cas9 and Cre/Lox system against re-emerging Pseudorabies virus, which caused the recent devastating swine pseudorabies outbreak in China. By CRISPR/Cas9 system, the virulent genes of the newly isolated strain were simultaneously substituted by marker genes, which were subsequently excised using Cre/Lox system for vaccine safety concern. Notably, single cell FACS technology was applied to further promote virus purification efficiency. The combination of these state-of-art technologies greatly accelerated vaccine development. Finally, vaccination and challenge experiments proved this vaccine candidate’s protective efficacy in pigs and the promise to control current pseudorabies outbreak. This is, to our knowledge, the first successful vaccine development based on gene edit technologies, demonstrating these technologies leap from laboratory to industry. It may pave the way for future express antiviral vaccine development. PMID:26777545

Blood-stage malaria vaccines: post-genome strategies for the identification of novel vaccine candidates.

PubMed

Ntege, Edward H; Takashima, Eizo; Morita, Masayuki; Nagaoka, Hikaru; Ishino, Tomoko; Tsuboi, Takafumi

2017-08-01

An efficacious malaria vaccine is necessary to advance the current control measures towards malaria elimination. To-date, only RTS,S/AS01, a leading pre-erythrocytic stage vaccine completed phase 3 trials, but with an efficacy of 28-36% in children, and 18-26% in infants, that waned over time. Blood-stage malaria vaccines protect against disease, and are considered effective targets for the logical design of next generation vaccines to improve the RTS,S field efficacy. Therefore, novel blood-stage vaccine candidate discovery efforts are critical, albeit with several challenges including, high polymorphisms in vaccine antigens, poor understanding of targets of naturally protective immunity, and difficulties in the expression of high AT-rich plasmodial proteins. Areas covered: PubMed ( www.ncbi.nlm.nih.gov/pubmed ) was searched to review the progress and future prospects of malaria vaccine research and development. We focused on post-genome vaccine candidate discovery, malaria vaccine development, sequence diversity, pre-clinical and clinical trials. Expert commentary: Post-genome high-throughput technologies using wheat germ cell-free protein synthesis technology and immuno-profiling with sera from malaria patients with clearly defined outcomes are highlighted to overcome current challenges of malaria vaccine candidate discovery.

Comparison of depopulation and S19-RB51 vaccination strategies for control of bovine brucellosis in high prevalence areas.

PubMed

Saez, J L; Sanz, C; Durán, M; García, P; Fernandez, F; Minguez, O; Carbajo, L; Mardones, F; Perez, A; Gonzalez, S; Dominguez, L; Alvarez, J

2014-06-21

RB51 vaccination can minimise the diagnostic problems associated with S19 vaccination of adult cattle, but its use for bovine brucellosis (BB) control remains controversial. Here, the evolution of BB prevalence in five high prevalence areas in Spain subjected to different control measures is described: herd depopulation of infected herds (I-III) or mass vaccination with RB51 and S19-RB51 vaccination of replacement heifers (IV-V). Annual data from the eradication campaigns were analysed at the special incidence area (SIA) level and the time to obtain herd prevalence levels of <1 per cent ('controlled status') was obtained at the local veterinary unit (LVU) level and compared using Cox's proportional hazard model. A higher annual rate of decrease in herd prevalence was observed in the SIAs subjected to vaccination (46.9%, 95% CI 43.5% to 50.0%) compared with those managed using stamping out (14.9%, 95% CI 9.6% to 19.9%). No significant differences in the time to achieve controlled status were observed between the stamping-out and vaccination strategies used at the LVU level, with median times of 60 (stamping-out LVUs) and 63 (vaccination LVUs) months. These results suggest that RB51 mass vaccination, in combination with the S19-RB51 vaccination of replacement heifers and strict implementation of other eradication measures, may provide results at least comparable with those resulting from a herd depopulation based strategy. British Veterinary Association.

Conserved epitope on influenza-virus hemagglutinin head defined by a vaccine-induced antibody

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raymond, Donald D.; Bajic, Goran; Ferdman, Jack

Antigenic variation requires frequent revision of annual influenza vaccines. Next-generation vaccine design strategies aim to elicit a broader immunity by directing the human immune response toward conserved sites on the principal viral surface protein, the hemagglutinin (HA). We describe a group of antibodies that recognize a hitherto unappreciated, conserved site on the HA of H1 subtype influenza viruses. Mutations in that site, which required a change in the H1 component of the 2017 vaccine, had not previously “taken over” among circulating H1 viruses. Our results encourage vaccine design strategies that resurface a protein to focus the immune response on amore » specific region.« less

Perspective on Global Measles Epidemiology and Control and the Role of Novel Vaccination Strategies.

PubMed

Coughlin, Melissa M; Beck, Andrew S; Bankamp, Bettina; Rota, Paul A

2017-01-19

Measles is a highly contagious, vaccine preventable disease. Measles results in a systemic illness which causes profound immunosuppression often leading to severe complications. In 2010, the World Health Assembly declared that measles can and should be eradicated. Measles has been eliminated in the Region of the Americas, and the remaining five regions of the World Health Organization (WHO) have adopted measles elimination goals. Significant progress has been made through increased global coverage of first and second doses of measles-containing vaccine, leading to a decrease in global incidence of measles, and through improved case based surveillance supported by the WHO Global Measles and Rubella Laboratory Network. Improved vaccine delivery methods will likely play an important role in achieving measles elimination goals as these delivery methods circumvent many of the logistic issues associated with subcutaneous injection. This review highlights the status of global measles epidemiology, novel measles vaccination strategies, and describes the pathway toward measles elimination.

Perspective on Global Measles Epidemiology and Control and the Role of Novel Vaccination Strategies

PubMed Central

Coughlin, Melissa M.; Beck, Andrew S.; Bankamp, Bettina; Rota, Paul A.

2017-01-01

Measles is a highly contagious, vaccine preventable disease. Measles results in a systemic illness which causes profound immunosuppression often leading to severe complications. In 2010, the World Health Assembly declared that measles can and should be eradicated. Measles has been eliminated in the Region of the Americas, and the remaining five regions of the World Health Organization (WHO) have adopted measles elimination goals. Significant progress has been made through increased global coverage of first and second doses of measles-containing vaccine, leading to a decrease in global incidence of measles, and through improved case based surveillance supported by the WHO Global Measles and Rubella Laboratory Network. Improved vaccine delivery methods will likely play an important role in achieving measles elimination goals as these delivery methods circumvent many of the logistic issues associated with subcutaneous injection. This review highlights the status of global measles epidemiology, novel measles vaccination strategies, and describes the pathway toward measles elimination. PMID:28106841

Surveillance of adverse effects following vaccination and safety of immunization programs.

PubMed

Waldman, Eliseu Alves; Luhm, Karin Regina; Monteiro, Sandra Aparecida Moreira Gomes; Freitas, Fabiana Ramos Martin de

2011-02-01

The aim of the review was to analyze conceptual and operational aspects of systems for surveillance of adverse events following immunization. Articles available in electronic format were included, published between 1985 and 2009, selected from the PubMed/Medline databases using the key words "adverse events following vaccine surveillance", "post-marketing surveillance", "safety vaccine" and "Phase IV clinical trials". Articles focusing on specific adverse events were excluded. The major aspects underlying the Public Health importance of adverse events following vaccination, the instruments aimed at ensuring vaccine safety, and the purpose, attributes, types, data interpretation issues, limitations, and further challenges in adverse events following immunization were describe, as well as strategies to improve sensitivity. The review was concluded by discussing the challenges to be faced in coming years with respect to ensuring the safety and reliability of vaccination programs.

Cost-effectiveness analyses of hepatitis A vaccine: a systematic review to explore the effect of methodological quality on the economic attractiveness of vaccination strategies.

PubMed

Anonychuk, Andrea M; Tricco, Andrea C; Bauch, Chris T; Pham, Ba'; Gilca, Vladimir; Duval, Bernard; John-Baptiste, Ava; Woo, Gloria; Krahn, Murray

2008-01-01

Hepatitis A vaccines have been available for more than a decade. Because the burden of hepatitis A virus has fallen in developed countries, the appropriate role of vaccination programmes, especially universal vaccination strategies, remains unclear. Cost-effectiveness analysis is a useful method of relating the costs of vaccination to its benefits, and may inform policy. This article systematically reviews the evidence on the cost effectiveness of hepatitis A vaccination in varying populations, and explores the effects of methodological quality and key modelling issues on the cost-effectiveness ratios.Cost-effectiveness/cost-utility studies of hepatitis A vaccine were identified via a series of literature searches (MEDLINE, EMBASE, HSTAR and SSCI). Citations and full-text articles were reviewed independently by two reviewers. Reference searching, author searches and expert consultation ensured literature saturation. Incremental cost-effectiveness ratios (ICERs) were abstracted for base-case analyses, converted to $US, year 2005 values, and categorised to reflect various levels of cost effectiveness. Quality of reporting, methodological issues and key modelling issues were assessed using frameworks published in the literature.Thirty-one cost-effectiveness studies (including 12 cost-utility analyses) were included from full-text article review (n = 58) and citation screening (n = 570). These studies evaluated universal mass vaccination (n = 14), targeted vaccination (n = 17) and vaccination of susceptibles (i.e. individuals initially screened for antibody and, if susceptible, vaccinated) [n = 13]. For universal vaccination, 50% of the ICERs were <$US20 000 per QALY or life-year gained. Analyses evaluating vaccination in children, particularly in high incidence areas, produced the most attractive ICERs. For targeted vaccination, cost effectiveness was highly dependent on the risk of infection.Incidence, vaccine cost and discount rate were the most influential

Design of different strategies of multivalent DNA-based vaccination against rabies and canine distemper in mice and dogs.

PubMed

Touihri, Leila; Ahmed, Sami Belhaj; Chtourou, Yacine; Daoud, Rahma; Bahloul, Chokri

2012-12-27

During the vaccination campaigns, puppies younger than 3 months old are not targeted and remain unvaccinated for at least the first year of their lives. Almost half of the reported rabid dogs are 6 months or younger. Hence, we should recommend the vaccination against rabies of young puppies. Unfortunately, owing to the exposure of puppies to infections with either canine parvovirus (CPV) or distemper virus (CDV) after the intervention of the vaccinators, owners are reluctant to vaccinate puppies against rabies. Therefore, it is necessary to include the CPV and CDV valences in the vaccine against rabies. Multivalent DNA-based vaccination in dogs, including rabies and distemper valences, could help in raising vaccine coverage. We have designed monovalent and multivalent DNA-based vaccine candidates for in vitro and in vivo assays. These plasmids encode to the rabies virus glycoprotein and/or the canine distemper virus hemagglutinin. The first strategy of multivalent DNA-based vaccination is by mixing plasmids encoding to a single antigen each. The second is by simply fusing the genes of the antigens together. The third is by adding the foot and mouth disease virus (FMDV) 2A oligopeptide gene into the antigen genes. The last strategy is by the design and use of a bicistronic plasmid with an "Internal Ribosome Entry Site" (IRES) domain. The monovalent construct against canine distemper was efficiently validated by inducing higher humoral immune responses compared to cell-culture-derived vaccine both in mice and dogs. All multivalent plasmids efficiently expressed both valences after in vitro transfection of BHK-21 cells. In BALB/c mice, the bicistronic IRES-dependant construct was the most efficient inducer of virus-neutralizing antibodies against both valences. It was able to induce better humoral immune responses compared to the administration of either cell-culture-derived vaccines or monovalent plasmids. The FMDV 2A was also efficient in the design of multivalent

Innovative vaccine delivery strategies in response to a cholera outbreak in the challenging context of Lake Chilwa. A rapid qualitative assessment.

PubMed

Heyerdahl, Leonard W; Ngwira, Bagrey; Demolis, Rachel; Nyirenda, Gabriel; Mwesawina, Maurice; Rafael, Florentina; Cavailler, Philippe; Bernard Le Gargasson, Jean; Mengel, Martin A; Gessner, Bradford D; Guillermet, Elise

2017-11-07

A reactive campaign using two doses of Shanchol Oral Cholera Vaccine (OCV) was implemented in 2016 in the Lake Chilwa Region (Malawi) targeting fish dependent communities. Three strategies for the second vaccine dose delivery (including delivery by a community leader and self-administration) were used to facilitate vaccine access. This assessment collected vaccine perceptions and opinions about the OCV campaign of 313 study participants, including: fishermen, fish traders, farmers, community leaders, and one health and one NGO officer. Socio-demographic surveys were conducted, In Depth Interviews and Focus Group Discussions were conducted before and during the campaign. Some fishermen perceived the traditional delivery strategy as reliable but less practical. Delivery by traditional leaders was acceptable for some participants while others worried about traditional leaders not being trained to deliver vaccines or beneficiaries taking doses on their own. A slight majority of beneficiaries considered the self-administration strategy practical while some beneficiaries worried about storing vials outside of the cold chain or losing vials. During the campaign, a majority of participants preferred receiving oral vaccines instead of injections given ease of intake and lack of pain. OCV was perceived as efficacious and safe. However, a lack of information on how sero-protection may be delayed and the degree of sero-protection led to loss of trust in vaccine potency among some participants who witnessed cholera cases among vaccinated individuals. OCV campaign implementation requires accompanying communication on protective levels, less than 100% vaccine efficacy, delays in onset of sero-protection, and out of cold chain storage. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Evaluation of Mucosal and Systemic Immune Responses Elicited by GPI-0100- Adjuvanted Influenza Vaccine Delivered by Different Immunization Strategies

PubMed Central

Liu, Heng; Patil, Harshad P.; de Vries-Idema, Jacqueline; Wilschut, Jan; Huckriede, Anke

2013-01-01

Vaccines for protection against respiratory infections should optimally induce a mucosal immune response in the respiratory tract in addition to a systemic immune response. However, current parenteral immunization modalities generally fail to induce mucosal immunity, while mucosal vaccine delivery often results in poor systemic immunity. In order to find an immunization strategy which satisfies the need for induction of both mucosal and systemic immunity, we compared local and systemic immune responses elicited by two mucosal immunizations, given either by the intranasal (IN) or the intrapulmonary (IPL) route, with responses elicited by a mucosal prime followed by a systemic boost immunization. The study was conducted in BALB/c mice and the vaccine formulation was an influenza subunit vaccine supplemented with GPI-0100, a saponin-derived adjuvant. While optimal mucosal antibody titers were obtained after two intrapulmonary vaccinations, optimal systemic antibody responses were achieved by intranasal prime followed by intramuscular boost. The latter strategy also resulted in the best T cell response, yet, it was ineffective in inducing nose or lung IgA. Successful induction of secretory IgA, IgG and T cell responses was only achieved with prime-boost strategies involving intrapulmonary immunization and was optimal when both immunizations were given via the intrapulmonary route. Our results underline that immunization via the lungs is particularly effective for priming as well as boosting of local and systemic immune responses. PMID:23936066

Human papillomavirus vaccine delivery strategies that achieved high coverage in low- and middle-income countries.

PubMed

LaMontagne, D Scott; Barge, Sandhya; Le, Nga Thi; Mugisha, Emmanuel; Penny, Mary E; Gandhi, Sanjay; Janmohamed, Amynah; Kumakech, Edward; Mosqueira, N Rocio; Nguyen, Nghi Quy; Paul, Proma; Tang, Yuxiao; Minh, Tran Hung; Uttekar, Bella Patel; Jumaan, Aisha O

2011-11-01

To assess human papillomavirus (HPV) vaccination coverage after demonstration projects conducted in India, Peru, Uganda and Viet Nam by PATH and national governments and to explore the reasons for vaccine acceptance or refusal. Vaccines were delivered through schools or health centres or in combination with other health interventions, and either monthly or through campaigns at fixed time points. Using a two-stage cluster sample design, the authors selected households in demonstration project areas and interviewed over 7000 parents or guardians of adolescent girls to assess coverage and acceptability. They defined full vaccination as the receipt of all three vaccine doses and used an open-ended question to explore acceptability. Vaccination coverage in school-based programmes was 82.6% (95% confidence interval, CI: 79.3-85.6) in Peru, 88.9% (95% CI: 84.7-92.4) in 2009 in Uganda and 96.1% (95% CI: 93.0-97.8) in 2009 in Viet Nam. In India, a campaign approach achieved 77.2% (95% CI: 72.4-81.6) to 87.8% (95% CI: 84.3-91.3) coverage, whereas monthly delivery achieved 68.4% (95% CI: 63.4-73.4) to 83.3% (95% CI: 79.3-87.3) coverage. More than two thirds of respondents gave as reasons for accepting the HPV vaccine that: (i) it protects against cervical cancer; (ii) it prevents disease, or (iii) vaccines are good. Refusal was more often driven by programmatic considerations (e.g. school absenteeism) than by opposition to the vaccine. High coverage with HPV vaccine among young adolescent girls was achieved through various delivery strategies in the developing countries studied. Reinforcing positive motivators for vaccine acceptance is likely to facilitate uptake.

Pharmacy management of vaccines.

PubMed

Cannon, H Eric

2007-09-01

Although standard vaccines have traditionally been granted full coverage in managed care, the recent introduction of several novel vaccine products has necessitated the revision of pharmacy management strategies throughout the nation. To review pharmacy management strategies for a number of emerging vaccines, with unique plan perspectives from SelectHealth, an Intermountain Healthcare company serving approximately 500,000 members in Utah. Because several recently introduced vaccines target previously unaddressed diseases and carry higher costs than traditional vaccines, several plans have adapted a novel approach to manage vaccine coverage on an individual product basis. At SelectHealth, recently introduced vaccines for rotavirus, respiratory syncytial virus (RSV), herpes zoster, and human papillomavirus (HPV) have required special attention in terms of pharmacy management. After carefully weighing acquisition and administration costs, anticipated uptake and use, direct and indirect health care costs averted, and quality of life issues, plan leadership decided to cover many of the new vaccines (i.e., rotavirus, RSV, and herpes zoster) under a nonstandard vaccination benefit. However, because substantial cost savings and high use of the quadrivalent HPV vaccine was anticipated within SelectHealth, the plan decided to fully cover the product. Although they complicate traditional pharmacy management, novel vaccines provide clinical benefit that managed care organizations cannot ignore. One universal strategy will not suffice in managing all the different vaccines entering the market, and a tailored approach should be employed based on the individual characteristics and use of each product.

Tuberculosis vaccines in clinical trials

PubMed Central

Rowland, Rosalind; McShane, Helen

2011-01-01

Effective prophylactic and/or therapeutic vaccination is a key strategy for controlling the global TB epidemic. The partial effectiveness of the existing TB vaccine, bacille Calmette–Guérin (BCG), suggests effective vaccination is possible and highlights the need for an improved vaccination strategy. Clinical trials are evaluating both modifications to the existing BCG immunization methods and also novel TB vaccines, designed to replace or boost BCG. Candidate vaccines in clinical development include live mycobacterial vaccines designed to replace BCG, subunit vaccines designed to boost BCG and therapeutic vaccines designed as an adjunct to chemotherapy. There is a great need for validated animal models, identification of immunological biomarkers of protection and field sites with the capacity for large-scale efficacy testing in order to develop and license a novel TB vaccine or regimen. PMID:21604985

A public health and budget impact analysis of vaccinating the elderly and at-risk adults with the 23-valent pneumococcal polysaccharide vaccine or 13-valent pneumococcal conjugate vaccine in the UK.

PubMed

Jiang, Yiling; Gauthier, Aline; Keeping, Sam; Carroll, Stuart

2014-12-01

Since the introduction of the routine childhood immunization, a change in epidemiology of pneumococcal disease has been seen in both children and adults. This study aimed to quantify the public health and budget impact of pneumococcal vaccination of the elderly and those in at risk groups in the UK. The model was adapted from a previous population-based Markov model. At-risk adults and the elderly were assumed to receive PPV23 or PCV13 vaccination or no vaccination. Over the study period (2012-2016), PPV23 vaccination led to a reduction in the number of invasive pneumococcal disease cases in most scenarios. The net budget impact ranged between £15 and £39 million (vs no vaccination) or between -£116 and -£93 million (vs PCV13). PPV23 vaccination program remains the optimal strategy from public health and budgetary perspectives despite epidemiological changes. PCV13 is likely to impose a significant budget with limited health benefits.

Therapeutic vaccines in HBV: lessons from HCV.

PubMed

Barnes, Eleanor

2015-02-01

Currently, millions of people infected with hepatitis B virus (HBV) are committed to decades of treatment with anti-viral therapy to control viral replication. However, new tools for immunotherapy that include both viral vectors and molecular checkpoint inhibitors are now available. This has led to a resurgence of interest in new strategies to develop immunotherapeutic strategies with the aim of inducing HBeAg seroconversion--an end-point that has been associated with a decrease in the rates of disease progression. Ultimately, a true cure will involve the elimination of covalently closed circular DNA which presents a greater challenge for immunotherapy. In this manuscript, I describe the development of immunotherapeutic strategies for HBV that are approaching or currently in clinical studies, and draw on observations of T cell function in natural infection supported by recent animal studies that may lead to additional rational vaccine strategies using checkpoint inhibitors. I also draw on our recent experience in developing potent vaccines for HCV prophylaxis based on simian adenoviral and MVA vectors used in prime-boost strategies in both healthy volunteers and HCV infected patients. I have shown that the induction of T cell immune responses is markedly attenuated when administered to people with persistent HCV viremia. These studies and recently published animal studies using the woodchuck model suggest that potent vaccines based on DNA or adenoviral vectored vaccination represent a rational way forward. However, combining these with drugs to suppress viral replication, alongside checkpoint inhibitors may be required to induce long-term immune control.

Next-generation dengue vaccines: novel strategies currently under development.

PubMed

Durbin, Anna P; Whitehead, Stephen S

2011-10-01

Dengue has become the most important arboviral infection worldwide with more than 30 million cases of dengue fever estimated to occur each year. The need for a dengue vaccine is great and several live attenuated dengue candidate vaccines are proceeding through clinical evaluation. The need to induce a balanced immune response against all four DENV serotypes with a single vaccine has been a challenge for dengue vaccine developers. A live attenuated DENV chimeric vaccine produced by Sanofi Pasteur has recently entered Phase III evaluation in numerous dengue-endemic regions of the world. Viral interference between serotypes contained in live vaccines has required up to three doses of the vaccine be given over a 12-month period of time. For this reason, novel DENV candidate vaccines are being developed with the goal of achieving a protective immune response with an immunization schedule that can be given over the course of a few months. These next-generation candidates include DNA vaccines, recombinant adenovirus vectored vaccines, alphavirus replicons, and sub-unit protein vaccines. Several of these novel candidates will be discussed.

Serum Cytokine Profiles Associated with Specific Adjuvants Used in a DNA Prime-Protein Boost Vaccination Strategy

PubMed Central

Buglione-Corbett, Rachel; Pouliot, Kimberly; Marty-Roix, Robyn; West, Kim; Wang, Shixia; Lien, Egil; Lu, Shan

2013-01-01

In recent years, heterologous prime-boost vaccines have been demonstrated to be an effective strategy for generating protective immunity, consisting of both humoral and cell-mediated immune responses against a variety of pathogens including HIV-1. Previous reports of preclinical and clinical studies have shown the enhanced immunogenicity of viral vector or DNA vaccination followed by heterologous protein boost, compared to using either prime or boost components alone. With such approaches, the selection of an adjuvant for inclusion in the protein boost component is expected to impact the immunogenicity and safety of a vaccine. In this study, we examined in a mouse model the serum cytokine and chemokine profiles for several candidate adjuvants: QS-21, Al(OH)3, monophosphoryl lipid A (MPLA) and ISCOMATRIX™ adjuvant, in the context of a previously tested pentavalent HIV-1 Env DNA prime-protein boost formulation, DP6-001. Our data revealed that the candidate adjuvants in the context of the DP6-001 formulation are characterized by unique serum cytokine and chemokine profiles. Such information will provide valuable guidance in the selection of an adjuvant for future AIDS vaccine development, with the ultimate goal of enhancing immunogenicity while minimizing reactogenicity associated with the use of an adjuvant. More significantly, results reported here will add to the knowledge on how to include an adjuvant in the context of a heterologous prime-protein boost vaccination strategy in general. PMID:24019983

Recombinant Alpha, Beta, and Epsilon Toxins of Clostridium perfringens: Production Strategies and Applications as Veterinary Vaccines

PubMed Central

Ferreira, Marcos Roberto A.; Moreira, Gustavo Marçal S. G.; da Cunha, Carlos Eduardo P.; Mendonça, Marcelo; Salvarani, Felipe M.; Moreira, Ângela N.; Conceição, Fabricio R.

2016-01-01

Clostridium perfringens is a spore-forming, commensal, ubiquitous bacterium that is present in the gastrointestinal tract of healthy humans and animals. This bacterium produces up to 18 toxins. The species is classified into five toxinotypes (A–E) according to the toxins that the bacterium produces: alpha, beta, epsilon, or iota. Each of these toxinotypes is associated with myriad different, frequently fatal, illnesses that affect a range of farm animals and humans. Alpha, beta, and epsilon toxins are the main causes of disease. Vaccinations that generate neutralizing antibodies are the most common prophylactic measures that are currently in use. These vaccines consist of toxoids that are obtained from C. perfringens cultures. Recombinant vaccines offer several advantages over conventional toxoids, especially in terms of the production process. As such, they are steadily gaining ground as a promising vaccination solution. This review discusses the main strategies that are currently used to produce recombinant vaccines containing alpha, beta, and epsilon toxins of C. perfringens, as well as the potential application of these molecules as vaccines for mammalian livestock animals. PMID:27879630

An effective strategy for influenza vaccination of healthcare workers in Australia: experience at a large health service without a mandatory policy.

PubMed

Heinrich-Morrison, Kristina; McLellan, Sue; McGinnes, Ursula; Carroll, Brendan; Watson, Kerrie; Bass, Pauline; Worth, Leon J; Cheng, Allen C

2015-02-06

Annual influenza vaccination of healthcare workers (HCWs) is recommended in Australia, but uptake in healthcare facilities has historically been low (approximately 50%). The objective of this study was to develop and implement a dedicated campaign to improve uptake of staff influenza annual vaccination at a large Australian health service. A quality improvement program was developed at Alfred Health, a tertiary metropolitan health service spanning 3 campuses. Pre-campaign evaluation was performed by questionnaire in 2013 to plan a multimodal vaccination strategy. Reasons for and against vaccination were captured. A campaign targeting clinical and non-clinical healthcare workers was then implemented between March 31 and July 31 2014. Proportional uptake of influenza vaccination was determined by campus and staff category. Pre-campaign questionnaire responses were received from 1328/6879 HCWs (response rate 20.4%), of which 76% were vaccinated. Common beliefs held by unvaccinated staff included vaccine ineffectiveness (37.1%), that vaccination makes staff unwell (21.0%), or that vaccination is not required because staff are at low risk for acquiring influenza (20.2%). In 2014, 6009/7480 (80.3%) staff were vaccinated, with significant improvement in uptake across all campuses and amongst nursing, medical and allied health staff categories from 2013 to 2014 (p < 0.0001). A non-mandatory multimodal strategy utilising social marketing and a customised staff database was successful in increasing influenza vaccination uptake by all staff categories. The sustainability of dedicated campaigns must be evaluated.

Evaluating the importance of policy amenable factors in explaining influenza vaccination: a cross-sectional multinational study

PubMed Central

Wheelock, Ana; Miraldo, Marisa; Thomson, Angus; Vincent, Charles; Sevdalis, Nick

2017-01-01

Objectives Despite continuous efforts to improve influenza vaccination coverage, uptake among high-risk groups remains suboptimal. We aimed to identify policy amenable factors associated with vaccination and to measure their importance in order to assist in the monitoring of vaccination sentiment and the design of communication strategies and interventions to improve vaccination rates. Setting The USA, the UK and France. Participants A total of 2412 participants were surveyed across the three countries. Outcome measures Self-reported influenza vaccination. Methods Between March and April 2014, a stratified random sampling strategy was employed with the aim of obtaining nationally representative samples in the USA, the UK and France through online databases and random-digit dialling. Participants were asked about vaccination practices, perceptions and feelings. Multivariable logistic regression was used to identify factors associated with past influenza vaccination. Results The models were able to explain 64%–80% of the variance in vaccination behaviour. Overall, sociopsychological variables, which are inherently amenable to policy, were better at explaining past vaccination behaviour than demographic, socioeconomic and health variables. Explanatory variables included social influence (physician), influenza and vaccine risk perceptions and traumatic childhood experiences. Conclusions Our results indicate that evidence-based sociopsychological items should be considered for inclusion into national immunisation surveys to gauge the public’s views, identify emerging concerns and thus proactively and opportunely address potential barriers and harness vaccination drivers. PMID:28706088

[From new vaccine to new target: revisiting influenza vaccination].

PubMed

Gérard, M

2011-09-01

Annual vaccination is since many years the corner stone of Influenza control strategy. Because conventional vaccine are needle-based, are less immunogenic in old people and induce only systemic IgG production, intranasal and intradermal vaccines that are recently or will be soon available in Belgium will offer distinct advantages. Intradermal vaccination is on the Belgian market since 2010. A stronger immune response that allows an antigen sparing strategy is elicited because antigens are delivered near the dermal dendritic cells. Local side effects are more pronounced than after intramuscular injection. The needle-free intranasal vaccine that has been approved for use in people less than 18 years old by the EMEA in October 2010 induces also a mucosal IgA response. Improved clinical results than with intramuscular vaccine has been documented in several studies in children. Several conditions are contraindication to nasal vaccination because of patterns of side effects and because the vaccine is an live-attenuated vaccine. Pregnant women has become a top priority for Influenza vaccination in the recommendations of the High Council of Health in Belgium since the 2009 H1N1 pandemic. Several studies has since then documented the increased risk for Influenza-related morbidity in pregnant women especially during the third trimester and independently of the presence of other comorbidities. Reduced incidence of documented Influenza and of Influenza-related hospitalizations are observed in the new born of vaccinated women until 6 months of age. Availability of new vaccines for Influenza and better knowledge of the benefit of vaccination in target populations are important tools to optimize vaccine coverage of the population.

Meta-analysis of vaccine effectiveness of mumps-containing vaccine under different immunization strategies in China.

PubMed

Wang, Huaqing; Hu, Yongmei; Zhang, Guomin; Zheng, Jingshan; Li, Li; An, Zhijie

2014-08-20

To evaluate vaccine effectiveness (VE) of mumps-containing vaccine (MuV) under different immunization strategies. We conducted Medline, Embase, China National Knowledge Internet (CNKI), and Wan Fang Database (WF) searches for Chinese and English language articles describing studies of mumps VE in a Chinese population. Evaluated articles were scored on quality using the Newcastle-Ottawa Scale. Meta-analysis was conducted using random effects models. Sensitivity analysis, subgroup analysis and meta-regression were conducted to explore heterogeneity. A total of 32 studies in 19 papers were included; 14 were case-control studies, and 18 were cohort studies. Half of the studies were of high quality; 41% were of moderate quality. The overall VE for mumps containing vaccine (either one dose or two doses) was 85% (95% CI 76-90%) for cohort studies and 88% (95% CI 82-92%) for case-control studies. Using random effects meta-regression we found significant differences in some study covariates; for instance, VE varied by population (VE=88% in day care versus 69% in pupil, p=0.008) and emergency versus routine immunization (VE=80% for routine immunization versus 95% for emergency immunization, p=0.041). However, these results must be interpreted with caution due to the low number of studies in subgroups, with the permutation test giving non-significant results that indicated that the results may be due to chance. MuV provides good protection from mumps infection. Further studies of mumps VE with larger sample sizes enabling subgroup analyses will be needed to confirm our findings. Copyright © 2014 Elsevier Ltd. All rights reserved.

Polymorphism in liver-stage malaria vaccine candidate proteins: immune evasion and implications for vaccine design.

PubMed

Flanagan, Katie L; Wilson, Kirsty L; Plebanski, Magdalena

2016-01-01

The pre-erythrocytic stage of infection by malaria parasites represents a key target for vaccines that aim to eradicate malaria. Two important broad immune evasion strategies that can interfere with vaccine efficacy include the induction of dendritic cell (DC) dysfunction and regulatory T cells (Tregs) by blood-stage malaria parasites, leading to inefficient priming of T cells targeting liver-stage infections. The parasite also uses 'surgical strike' strategies, whereby polymorphism in pre-erythrocytic antigens can interfere with host immunity. Specifically, we review how even single amino acid changes in T cell epitopes can lead to loss of binding to major histocompatibility complex (MHC), lack of cross-reactivity, or antagonism and immune interference, where simultaneous or sequential stimulation with related variants of the same T cell epitope can cause T cell anergy or the conversion of effector to immunosuppressive T cell phenotypes.

Strategies for continuous evaluation of the benefit-risk profile of HPV-16/18-AS04-adjuvanted vaccine.

PubMed

Angelo, Maria-Genalin; Taylor, Sylvia; Struyf, Frank; Tavares Da Silva, Fernanda; Arellano, Felix; David, Marie-Pierre; Dubin, Gary; Rosillon, Dominique; Baril, Laurence

2014-11-01

The HPV types 16/18-AS04-adjuvanted cervical cancer vaccine, Cervarix(®) (HPV-16/18-vaccine, GlaxoSmithKline, Belgium) was first approved in 2007 and is licensed in 134 countries for the prevention of persistent infection, premalignant cervical lesions and cervical cancer caused by oncogenic HPV. Benefit-risk status requires continual re-evaluation as vaccine uptake increases, as the epidemiology of the disease evolves and as new information becomes available. This paper provides an example of benefit-risk considerations and risk-management planning. Evaluation of the benefit-risk of HPV-16/18-vaccine post-licensure includes studies with a range of designs in many countries and in collaboration with national public agencies and regulatory authorities. The strategy to assess benefit versus risk will continue to evolve and adapt to the changing HPV-16/18-vaccine market.

Cost-effectiveness of novel vaccines for tuberculosis control: a decision analysis study

PubMed Central

2011-01-01

Background The development of a successful new tuberculosis (TB) vaccine would circumvent many limitations of current diagnostic and treatment practices. However, vaccine development is complex and costly. We aimed to assess the potential cost effectiveness of novel vaccines for TB control in a sub-Saharan African country - Zambia - relative to the existing strategy of directly observed treatment, short course (DOTS) and current level of bacille Calmette-Guérin (BCG) vaccination coverage. Methods We conducted a decision analysis model-based simulation from the societal perspective, with a 3% discount rate and all costs expressed in 2007 US dollars. Health outcomes and costs were projected over a 30-year period, for persons born in Zambia (population 11,478,000 in 2005) in year 1. Initial development costs for single vaccination and prime-boost strategies were prorated to the Zambian share (0.398%) of global BCG vaccine coverage for newborns. Main outcome measures were TB-related morbidity, mortality, and costs over a range of potential scenarios for vaccine efficacy. Results Relative to the status quo strategy, a BCG replacement vaccine administered at birth, with 70% efficacy in preventing rapid progression to TB disease after initial infection, is estimated to avert 932 TB cases and 422 TB-related deaths (prevention of 199 cases/100,000 vaccinated, and 90 deaths/100,000 vaccinated). This would result in estimated net savings of $3.6 million over 30 years for 468,073 Zambians born in year 1 of the simulation. The addition of a booster at age 10 results in estimated savings of $5.6 million compared to the status quo, averting 1,863 TB cases and 1,011 TB-related deaths (prevention of 398 cases/100,000 vaccinated, and of 216 deaths/100,000 vaccinated). With vaccination at birth alone, net savings would be realized within 1 year, whereas the prime-boost strategy would require an additional 5 years to realize savings, reflecting a greater initial development cost

Human papillomavirus vaccine delivery strategies that achieved high coverage in low- and middle-income countries

PubMed Central

Barge, Sandhya; Le, Nga Thi; Mugisha, Emmanuel; Penny, Mary E; Gandhi, Sanjay; Janmohamed, Amynah; Kumakech, Edward; Mosqueira, N Rocio; Nguyen, Nghi Quy; Paul, Proma; Tang, Yuxiao; Minh, Tran Hung; Uttekar, Bella Patel; Jumaan, Aisha O

2011-01-01

Abstract Objective To assess human papillomavirus (HPV) vaccination coverage after demonstration projects conducted in India, Peru, Uganda and Viet Nam by PATH and national governments and to explore the reasons for vaccine acceptance or refusal. Methods Vaccines were delivered through schools or health centres or in combination with other health interventions, and either monthly or through campaigns at fixed time points. Using a two-stage cluster sample design, the authors selected households in demonstration project areas and interviewed over 7000 parents or guardians of adolescent girls to assess coverage and acceptability. They defined full vaccination as the receipt of all three vaccine doses and used an open-ended question to explore acceptability. Findings Vaccination coverage in school-based programmes was 82.6% (95% confidence interval, CI: 79.3–85.6) in Peru, 88.9% (95% CI: 84.7–92.4) in 2009 in Uganda and 96.1% (95% CI: 93.0–97.8) in 2009 in Viet Nam. In India, a campaign approach achieved 77.2% (95% CI: 72.4–81.6) to 87.8% (95% CI: 84.3–91.3) coverage, whereas monthly delivery achieved 68.4% (95% CI: 63.4–73.4) to 83.3% (95% CI: 79.3–87.3) coverage. More than two thirds of respondents gave as reasons for accepting the HPV vaccine that: (i) it protects against cervical cancer; (ii) it prevents disease, or (iii) vaccines are good. Refusal was more often driven by programmatic considerations (e.g. school absenteeism) than by opposition to the vaccine. Conclusion High coverage with HPV vaccine among young adolescent girls was achieved through various delivery strategies in the developing countries studied. Reinforcing positive motivators for vaccine acceptance is likely to facilitate uptake. PMID:22084528

Optimal control for Malaria disease through vaccination

NASA Astrophysics Data System (ADS)

Munzir, Said; Nasir, Muhammad; Ramli, Marwan

2018-01-01

Malaria is a disease caused by an amoeba (single-celled animal) type of plasmodium where anopheles mosquito serves as the carrier. This study examines the optimal control problem of malaria disease spread based on Aron and May (1982) SIR type models and seeks the optimal solution by minimizing the prevention of the spreading of malaria by vaccine. The aim is to investigate optimal control strategies on preventing the spread of malaria by vaccination. The problem in this research is solved using analytical approach. The analytical method uses the Pontryagin Minimum Principle with the symbolic help of MATLAB software to obtain optimal control result and to analyse the spread of malaria with vaccination control.

Storytelling in the context of vaccine refusal: a strategy to improve communication and immunisation.

PubMed

Cawkwell, Philip B; Oshinsky, David

2016-03-01

The December 2014 outbreak of measles in California impacted over 100 children and served as a reminder that this disease still plagues the USA, even 50 years following the first licensed vaccine. Refusal of vaccination is a complicated and multifaceted issue, one that clearly demands a closer look by paediatricians and public health officials alike. While medical doctors and scientists are trained to practice 'evidence-based medicine', and studies of vaccine safety and efficacy speak the language of statistics, there is reason to believe that this is not the most effective strategy for communicating with all groups of parents. Herein, we consider other methods such as narrative practices that employ stories and appeal more directly to parents. We also examine how doctors are trained to disseminate information and whether there are reasonable supplementary methods that could be used to improve vaccine communication and ultimately immunisation rates. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Vaccine decision-making begins in pregnancy: Correlation between vaccine concerns, intentions and maternal vaccination with subsequent childhood vaccine uptake.

PubMed

Danchin, M H; Costa-Pinto, J; Attwell, K; Willaby, H; Wiley, K; Hoq, M; Leask, J; Perrett, K P; O'Keefe, Jacinta; Giles, M L; Marshall, H

2017-08-12

Maternal and childhood vaccine decision-making begins prenatally. Amongst pregnant Australian women we aimed to ascertain vaccine information received, maternal immunisation uptake and attitudes and concerns regarding childhood vaccination. We also aimed to determine any correlation between a) intentions and concerns regarding childhood vaccination, (b) concerns about pregnancy vaccination, (c) socioeconomic status (SES) and (d) uptake of influenza and pertussis vaccines during pregnancy and routine vaccines during childhood. Women attending public antenatal clinics were recruited in three Australian states. Surveys were completed on iPads. Follow-up phone surveys were done three to six months post delivery, and infant vaccination status obtained via the Australian Childhood Immunisation Register (ACIR). Between October 2015 and March 2016, 975 (82%) of 1184 mothers consented and 406 (42%) agreed to a follow up survey, post delivery. First-time mothers (445; 49%) had significantly more vaccine concerns in pregnancy and only 73% had made a decision about childhood vaccination compared to 89% of mothers with existing children (p-value<0.001). 66% of mothers reported receiving enough information during pregnancy on childhood vaccination. In the post delivery survey, 46% and 82% of mothers reported receiving pregnancy influenza and pertussis vaccines respectively. The mother's degree of vaccine hesitancy and two attitudinal factors were correlated with vaccine uptake post delivery. There was no association between reported maternal vaccine uptake or SES and childhood vaccine uptake. First time mothers are more vaccine hesitant and undecided about childhood vaccination, and only two thirds of all mothers believed they received enough information during pregnancy. New interventions to improve both education and communication on childhood and maternal vaccines, delivered by midwives and obstetricians in the Australian public hospital system, may reduce vaccine hesitancy

Measuring vaccine confidence: analysis of data obtained by a media surveillance system used to analyse public concerns about vaccines.

PubMed

Larson, Heidi J; Smith, David M D; Paterson, Pauline; Cumming, Melissa; Eckersberger, Elisabeth; Freifeld, Clark C; Ghinai, Isaac; Jarrett, Caitlin; Paushter, Louisa; Brownstein, John S; Madoff, Lawrence C

2013-07-01

The intensity, spread, and effects of public opinion about vaccines are growing as new modes of communication speed up information sharing, contributing to vaccine hesitancy, refusals, and disease outbreaks. We aimed to develop a new application of existing surveillance systems to detect and characterise early signs of vaccine issues. We also aimed to develop a typology of concerns and a way to assess the priority of each concern. Following preliminary research by The Vaccine Confidence Project, media reports (eg, online articles, blogs, government reports) were obtained using the HealthMap automated data collection system, adapted to monitor online reports about vaccines, vaccination programmes, and vaccine-preventable diseases. Any reports that did not meet the inclusion criteria--any reference to a human vaccine or vaccination campaign or programme that was accessible online--were removed from analysis. Reports were manually analysed for content and categorised by concerns, vaccine, disease, location, and source of report, and overall positive or negative sentiment towards vaccines. They were then given a priority level depending on the seriousness of the reported event and time of event occurrence. We used descriptive statistics to analyse the data collected during a period of 1 year, after refinements to the search terms and processes had been made. We analysed data from 10,380 reports (from 144 countries) obtained between May 1, 2011, and April 30, 2012. 7171 (69%) contained positive or neutral content and 3209 (31%) contained negative content. Of the negative reports, 1977 (24%) were associated with impacts on vaccine programmes and disease outbreaks; 1726 (21%) with beliefs, awareness, and perceptions; 1371 (16%) with vaccine safety; and 1336 (16%) with vaccine delivery programmes. We were able to disaggregate the data by country and vaccine type, and monitor evolution of events over time and location in specific regions where vaccine concerns were high

Current State in the Development of Candidate Therapeutic HPV Vaccines

PubMed Central

Yang, Andrew; Jeang, Jessica; Cheng, Kevin; Cheng, Ting; Yang, Benjamin; Wu, T.-C.; Hung, Chien-Fu

2016-01-01

Summary The identification of human papillomavirus (HPV) as an etiological factor for HPV-associated malignancies creates the opportunity to control these cancers through vaccination. Currently, available preventive HPV vaccines have not yet demonstrated strong evidences for therapeutic effects against established HPV infections and lesions. Furthermore, HPV infections remain extremely common. Thus, there is urgent need for therapeutic vaccines to treat existing HPV infections and HPV-associated diseases. Therapeutic vaccines differ from preventive vaccines in that they are aimed at generating cell-mediated immunity rather than neutralizing antibodies. The HPV-encoded early proteins, especially oncoproteins E6 and E7, form ideal targets for therapeutic HPV vaccines since they are consistently expressed in HPV-associated malignancies and precancerous lesions, playing crucial roles in the generation and maintenance of HPV-associated disease. Our review will cover various therapeutic vaccines in development for the treatment of HPV-associated lesions and cancers. Furthermore, we review strategies to enhance vaccine efficacy and the latest clinical trials on therapeutic HPV vaccines. PMID:26901118

Hantavirus Gc induces long-term immune protection via LAMP-targeting DNA vaccine strategy.

PubMed

Jiang, Dong-Bo; Zhang, Jin-Peng; Cheng, Lin-Feng; Zhang, Guan-Wen; Li, Yun; Li, Zi-Chao; Lu, Zhen-Hua; Zhang, Zi-Xin; Lu, Yu-Chen; Zheng, Lian-He; Zhang, Fang-Lin; Yang, Kun

2018-02-01

Hemorrhagic fever with renal syndrome (HFRS) occurs widely throughout Eurasia. Unfortunately, there is no effective treatment, and prophylaxis remains the best option against the major pathogenic agent, hantaan virus (HTNV), which is an Old World hantavirus. However, the absence of cellular immune responses and immunological memory hampers acceptance of the current inactivated HFRS vaccine. Previous studies revealed that a lysosome-associated membrane protein 1 (LAMP1)-targeting strategy involving a DNA vaccine based on the HTNV glycoprotein Gn successfully conferred long-term immunity, and indicated that further research on Gc, another HTNV antigen, was warranted. Plasmids encoding Gc and lysosome-targeted Gc, designated pVAX-Gc and pVAX-LAMP/Gc, respectively, were constructed. Proteins of interest were identified by fluorescence microscopy following cell line transfection. Five groups of 20 female BALB/c mice were subjected to the following inoculations: inactivated HTNV vaccine, pVAX-LAMP/Gc, pVAX-Gc, and, as the negative controls, pVAX-LAMP or the blank vector pVAX1. Humoral and cellular immunity were assessed by enzyme-linked immunosorbent assays (ELISAs) and 15-mer peptide enzyme-linked immunospot (ELISpot) epitope mapping assays. Repeated immunization with pVAX-LAMP/Gc enhanced adaptive immune responses, as demonstrated by the specific and neutralizing antibody titers and increased IFN-γ production. The inactivated vaccine induced a comparable humoral reaction, but the negative controls only elicited insignificant responses. Using a mouse model of HTNV challenge, the in vivo protection conferred by the inactivated vaccine and Gc-based constructs (with/without LAMP recombination) was confirmed. Evidence of pan-epitope reactions highlighted the long-term cellular response to the LAMP-targeting strategy, and histological observations indicated the safety of the LAMP-targeting vaccines. The long-term protective immune responses induced by pVAX-LAMP/Gc may be

Emergency response vaccines--a challenge for the public sector and the vaccine industry.

PubMed

Milstien, Julie; Lambert, Scott

2002-11-22

In partnership with industry, WHO has developed a number of strategies to facilitate access to vaccines recommended for use in national immunization programs. These strategies have been necessitated by the increasing fragility of vaccine supply for developing markets. The potential global spread of epidemic disease has made it imperative to expand these efforts. A new concept is proposed, that of essential vaccines, defined as "vaccines of public health importance that should be accessible to all people at risk". Essential vaccines will include emergency response vaccines that have become important due to resurgent outbreaks, threatening global pandemics, and situations where a global emergency immunization response may be needed. While some of the approaches already developed will be applicable to emergency response vaccines, other novel approaches requiring public sector intervention will be necessary. Procurement, financing and allocation of these emergency response vaccines, if left to governments or private individuals based on ability to pay, will threaten equitable access. The challenge will be to ensure development of and equitable access to these vaccines while not threatening the already fragile supply of other essential vaccines.

Rational design of gene-based vaccines.

PubMed

Barouch, Dan H

2006-01-01

Vaccine development has traditionally been an empirical discipline. Classical vaccine strategies include the development of attenuated organisms, whole killed organisms, and protein subunits, followed by empirical optimization and iterative improvements. While these strategies have been remarkably successful for a wide variety of viruses and bacteria, these approaches have proven more limited for pathogens that require cellular immune responses for their control. In this review, current strategies to develop and optimize gene-based vaccines are described, with an emphasis on novel approaches to improve plasmid DNA vaccines and recombinant adenovirus vector-based vaccines. Copyright 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Willingness to pay for hypothetical malaria vaccines in rural Burkina Faso.

PubMed

Sauerborn, Rainer; Gbangou, Adjima; Dong, Hengjin; Przyborski, Jude M; Lanzer, Michael

2005-01-01

This study aims to set priorities for anti-disease malaria vaccines by determining community preference in a hyperendemic area. A bidding game technique was used to elucidate willingness to pay in rural Burkina Faso and 2,326 adults were interviewed. It is shown that there are significant differences between community preference for an anti-disease vaccine aimed at reducing pathology in pregnant women, and for a vaccine directed against childhood malaria. While the target population was willing to pay CFAfr 2101 for a vaccine against maternal malaria, its members were prepared to pay only CFAfr 1433 for a vaccine against childhood malaria. Whilst it is increasingly likely that anti-disease malaria vaccines will become available in the foreseeable future, lessons from the past suggest that a lack of acceptance and support from the intended recipients may lead to less than optimal compliance, and hence efficacy. For the planning of vaccine development and application strategies, it is therefore highly important to take community views into account. Here it is argued that such information could help researchers and funding agencies to set priorities for future vaccine research.

Determining the Optimal Vaccination Schedule for Herpes Zoster: a Cost-Effectiveness Analysis.

PubMed

Le, Phuc; Rothberg, Michael B

2017-02-01

The Advisory Committee on Immunization Practices recommends a single dose of herpes zoster (HZ) vaccine in persons aged 60 years or older, but the efficacy decreases to zero after approximately 10 years. A booster dose administered after 10 years might extend protection, but the cost-effectiveness of a booster strategy has not been examined. We aimed to determine the optimal schedule for HZ vaccine DESIGN: We built a Markov model to follow patients over their lifetime. From the societal perspective, we compared costs and quality-adjusted life years (QALYs) saved of 11 strategies to start and repeat HZ vaccine at different ages. Adults aged 60 years. HZ vaccine. Costs, quality-adjusted life years (QALYs), and incremental costs per QALY saved. At a $100,000/QALY threshold, "vaccination at 70 plus one booster" was the most cost-effective strategy, with an incremental cost-effectiveness ratio (ICER) of $36,648/QALY. "Vaccination at 60 plus two boosters" was more effective, but had an ICER of $153,734/QALY. In deterministic sensitivity analysis, "vaccination at 60 plus two boosters" cost < $100,000/QALY if compliance rate was > 67 % or vaccine cost was < $156 per dose. In probabilistic sensitivity analysis, "vaccination at 70 plus one booster" was preferred at a willingness-to-pay of up to $135,000/QALY. Under current assumptions, initiating HZ vaccine at age 70 years with one booster dose 10 years later appears optimal. Future data regarding compliance with or efficacy of a booster could affect these conclusions.

[Economic evaluation of an infant immunization program in Mexico, based on 13-valent pneumococcal conjugated vaccines].

PubMed

Muciño-Ortega, Emilio; Mould-Quevedo, Joaquín Federico; Farkouh, Raymond; Strutton, David

2011-01-01

Vaccination is an effective intervention for reduce child morbidity and mortality associated to pneumococcus. The availability of new anti-pneumococcal vaccines makes it necessary to evaluate its potential impact on public health and costs related to their implementation. The aim of this study was to estimate the cost-effectiveness and cost-utility of immunization strategies based on pneumococcal conjugated vaccines (PCV's) currently available in Mexico from a third payer perspective. A decision tree model was developed to assess both, economic and health impact, of anti-pneumococcal vaccination in children <2 years (lifetime time horizon, discount rate: 5% annual). Comparators were: no-vaccination (reference) and strategies based on 7, 10 and 13-valent PCV's. Effectiveness measures were: child deaths avoided, life-years gained (LYG) and quality adjusted life years (QALY's) gained. Effectiveness, utility, local epidemiology and cost of treating pneumococcal diseases were extracted from published sources. Univariate sensitivity analysis were performed. Immunization dominates no-vaccination: strategy based on 13-valent vaccine prevented 16.205 deaths, gained 331.230 LY's and 332.006 QALY's and saved US$1.307/child vaccinated. Strategies based on 7 and 10-valent PCV's prevented 13.806 and 5.589 deaths, gained 282.193 and 114.251 LY's, 282.969 and 114.972 QALY's and saved US$1.084 and US$731/child vaccinated, respectively. These results were robust to variations in herd immunity and lower immunogenicity of 10-valent vaccine. In Mexico, immunization strategies based on 7, 10 and 13-valent PCV's would be cost-saving interventions, however, health outcomes and savings of the strategy based on 13-valent vaccine are greater than those estimated for 7 and 10-valent PCV's. Copyright © 2011 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

First nations people's perspectives on barriers and supports for enhancing HPV vaccination: Foundations for sustainable, community-driven strategies.

PubMed

Henderson, R I; Shea-Budgell, M; Healy, C; Letendre, A; Bill, L; Healy, B; Bednarczyk, R A; Mrklas, K; Barnabe, C; Guichon, J; Bedingfield, N; MacDonald, S; Colquhoun, A; Glaze, S; Nash, T; Bell, C; Kellner, J; Richardson, R; Dixon, T; Starlight, J; Runner, G; Nelson, G

2018-04-01

In Canada, Indigenous people have higher human papillomavirus (HPV) infection rates, lower screening rates for cervical cancer, and higher rates of invasive cancer, leading to worse cervical cancer-related outcomes than observed in non-Indigenous Canadian women. Lingering harms from European colonization drive these health inequities and create public health challenges. Policy guidance is needed to optimize HPV vaccination rates and, thereby, decrease the burden of HPV-related illness, including high-morbidity surgical procedures and chemo-radiotherapy. The Enhancing HPV Vaccination In First Nations Populations in Alberta (EHVINA) project focuses on First Nations, a diverse subset of recognized Indigenous people in Canada, and seeks to increase HPV vaccination among girls and boys living in First Nation communities. Developing an effective strategy requires partnership with affected communities to better understand knowledge and perceptions about cancer, healthcare, and the HPV vaccine. A 2017 community gathering was convened to engage First Nations community members, health directors, and health services researchers in dialogue around unique barriers and supports to HPV vaccination in Alberta. Voices of community Elders, parents, health directors, and cancer survivors (n=24) are presented as qualitative evidence to help inform intervention design. Key findings from discussions indicate barriers to HPV vaccination include resource constraints and service infrastructure gaps, historical mistrust in healthcare systems, impacts of changing modes of communication, and community sensitivities regarding sexual health promotion. Supports were identified as strengthened inter-generational relationships in communities. Ongoing dialogue and co-development of community-based strategies to increase HPV vaccine uptake are required. The identification of possible barriers to HPV vaccination in a Canadian Indigenous population contributes to limited global literature on this

Herpes zoster vaccine: A health economic evaluation for Switzerland.

PubMed

Blank, Patricia R; Ademi, Zanfina; Lu, Xiaoyan; Szucs, Thomas D; Schwenkglenks, Matthias

2017-07-03

Herpes zoster (HZ) or "shingles" results from a reactivation of the varicella zoster virus (VZV) acquired during primary infection (chickenpox) and surviving in the dorsal root ganglia. In about 20% of cases, a complication occurs, known as post-herpetic neuralgia (PHN). A live attenuated vaccine against VZV is available for the prevention of HZ and subsequent PHN. The present study aims to update an earlier evaluation estimating the cost-effectiveness of the HZ vaccine from a Swiss third party payer perspective. It takes into account updated vaccine prices, a different age cohort, latest clinical data and burden of illness data. A Markov model was developed to simulate the lifetime consequences of vaccinating 15% of the Swiss population aged 65-79 y. Information from sentinel data, official statistics and published literature were used. Endpoints assessed were number of HZ and PHN cases, quality-adjusted life years (QALYs), costs of hospitalizations, consultations and prescriptions. Based on a vaccine price of CHF 162, the vaccination strategy accrued additional costs of CHF 17,720,087 and gained 594 QALYs. The incremental cost-effectiveness ratio (ICER) was CHF 29,814 per QALY gained. Sensitivity analyses showed that the results were most sensitive to epidemiological inputs, utility values, discount rates, duration of vaccine efficacy, and vaccine price. Probabilistic sensitivity analyses indicated a more than 99% chance that the ICER was below 40,000 CHF per QALY. Findings were in line with existing cost-effectiveness analyses of HZ vaccination. This updated study supports the value of an HZ vaccination strategy targeting the Swiss population aged 65-79 y.

Evaluation of Heliostat Standby Aiming Strategies to Reduce Avian Flux Hazards and Impacts on Operational Performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wendelin, Timothy J; Ho, Clifford K.; Horstman, Luke

This paper presents a study of alternative heliostat standby aiming strategies and their impact on avian flux hazards and operational performance of a concentrating solar power plant. A mathematical model was developed that predicts the bird-feather temperature as a function of solar irradiance, thermal emittance, convection, and thermal properties of the feather. The irradiance distribution in the airspace above the Ivanpah Unit 2 heliostat field was simulated using a ray-trace model for two different times of the day, four days of the year, and nine different standby aiming strategies. The impact of the alternative aiming strategies on operational performance wasmore » assessed by comparing the heliostat slew times from standby position to the receiver for the different aiming strategies. Increased slew times increased a proxy start-up time that reduced the simulated annual energy production. Results showed that spreading the radial aim points around the receiver to a distance of ~150 m or greater reduced the hazardous exposure times that the feather temperature exceeded the hazard metric of 160 degrees C. The hazardous exposure times were reduced by ~23% and 90% at a radial spread of aim points extending to 150 m and 250 m, respectively, but the simulated annual energy production decreased as a result of increased slew times. Single point-focus aiming strategies were also evaluated, but these strategies increased the exposure hazard relative to other aiming strategies.« less

Idiotype vaccines for lymphoma: Potential factors predicting the induction of immune responses

PubMed Central

Inoges, Susana; de Cerio, Ascension Lopez-Diaz; Villanueva, Helena; Pastor, Fernando; Soria, Elena; Bendandi, Maurizio

2011-01-01

Over the last two decades, lymphoma idiotype vaccines have been the first human cancer vaccines to show striking evidence of biological and clinical efficacy on the one hand, as well as clinical benefit on the other. More recently, however, three large-scale, independent, randomized clinical trials on idiotypic vaccination have failed to achieve their main clinical endpoints for reasons likely to depend more on flaws in each clinical trial’s study design than on each vaccination strategy per se. Independently of these considerations, a major hurdle for the development of this substantially innocuous and yet potentially very effective type of treatment has been the fact that, even to date, no factors ascertainable before vaccination have been prospectively singled out as predictors of subsequently vaccine-induced, idiotype-specific immune as well as clinical responses. The aim of this review article is precisely to analyze what has been and what could be done in this respect in order to give a greater chance of success to future trials aimed at regulatory approval of idiotype vaccines. PMID:21773074

Evaluating the importance of policy amenable factors in explaining influenza vaccination: a cross-sectional multinational study.

PubMed

Wheelock, Ana; Miraldo, Marisa; Thomson, Angus; Vincent, Charles; Sevdalis, Nick

2017-07-12

Despite continuous efforts to improve influenza vaccination coverage, uptake among high-risk groups remains suboptimal. We aimed to identify policy amenable factors associated with vaccination and to measure their importance in order to assist in the monitoring of vaccination sentiment and the design of communication strategies and interventions to improve vaccination rates. The USA, the UK and France. A total of 2412 participants were surveyed across the three countries. Self-reported influenza vaccination. Between March and April 2014, a stratified random sampling strategy was employed with the aim of obtaining nationally representative samples in the USA, the UK and France through online databases and random-digit dialling. Participants were asked about vaccination practices, perceptions and feelings. Multivariable logistic regression was used to identify factors associated with past influenza vaccination. The models were able to explain 64%-80% of the variance in vaccination behaviour. Overall, sociopsychological variables, which are inherently amenable to policy, were better at explaining past vaccination behaviour than demographic, socioeconomic and health variables. Explanatory variables included social influence (physician), influenza and vaccine risk perceptions and traumatic childhood experiences. Our results indicate that evidence-based sociopsychological items should be considered for inclusion into national immunisation surveys to gauge the public's views, identify emerging concerns and thus proactively and opportunely address potential barriers and harness vaccination drivers. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Impact of combined vector-control and vaccination strategies on transmission dynamics of dengue fever: a model-based analysis.

PubMed

Knerer, Gerhart; Currie, Christine S M; Brailsford, Sally C

2015-06-01

Dengue fever is a vector-borne disease prevalent in tropical and subtropical regions. It is an important public health problem with a considerable and often under-valued disease burden in terms of frequency, cost and quality-of-life. Recent literature reviews have documented the development of mathematical models of dengue fever both to identify important characteristics for future model development as well as to assess the impact of dengue control interventions. Such reviews highlight the importance of short-term cross-protection; antibody-dependent enhancement; and seasonality (in terms of both favourable and unfavourable conditions for mosquitoes). The compartmental model extends work by Bartley (2002) and combines the following factors: seasonality, age-structure, consecutive infection by all four serotypes, cross-protection and immune enhancement, as well as combined vector-host transmission. The model is used to represent dengue transmission dynamics using parameters appropriate for Thailand and to assess the potential impact of combined vector-control and vaccination strategies including routine and catch-up vaccination strategies on disease dynamics. When seasonality and temporary cross-protection between serotypes are included, the model is able to approximate the observed incidence of dengue fever in Thailand. We find vaccination to be the most effective single intervention, albeit with imperfect efficacy (30.2 %) and limited duration of protection. However, in combination, control interventions and vaccination exhibit a marked impact on dengue fever transmission. This study shows that an imperfect vaccine can be a useful weapon in reducing disease spread within the community, although it will be most effective when promoted as one of several strategies for combating dengue fever transmission.

Influenza vaccines: an Asia-Pacific perspective.

PubMed

Jennings, Lance C

2013-11-01

This article provides an overview of some aspects of seasonal, pre-pandemic and pandemic influenza vaccines and initiatives aimed to increase influenza vaccine use within the Asia-Pacific region. Expanding the use of influenza vaccines in the Asia-Pacific region faces many challenges. Despite the recent regional history for the emergence of novel viruses, SARS, the H5N1 and H7N9, and the generation of and global seeding of seasonal influenza viruses and initiatives by WHO and other organisations to expand influenza awareness, the use of seasonal influenza vaccines remains low. The improvement in current vaccine technologies with the licensing of quadrivalent, live-attenuated, cell culture-based, adjuvanted and the first recombinant influenza vaccine is an important step. The development of novel influenza vaccines able to provide improved protection and with improved manufacturing capacity is also advancing rapidly. However, of ongoing concern are seasonal influenza impact and the low use of seasonal influenza vaccines in the Asia-Pacific region. Improved influenza control strategies and their implementation in the region are needed. Initiatives by the World Health Organization (WHO), and specifically the Western Pacific Regional Office of WHO, are focusing on consistent vaccine policies and guidelines in countries in the region. The Asian-Pacific Alliance for the Control of Influenza (APACI) is contributing through the coordination of influenza advocacy initiates. © 2013 Blackwell Publishing Ltd.

Cost Effectiveness of Influenza Vaccine for U.S. Children: Live Attenuated and Inactivated Influenza Vaccine.

PubMed

Shim, Eunha; Brown, Shawn T; DePasse, Jay; Nowalk, Mary Patricia; Raviotta, Jonathan M; Smith, Kenneth J; Zimmerman, Richard K

2016-09-01

Prior studies showed that live attenuated influenza vaccine (LAIV) is more effective than inactivated influenza vaccine (IIV) in children aged 2-8 years, supporting the Centers for Disease Control and Prevention (CDC) recommendations in 2014 for preferential LAIV use in this age group. However, 2014-2015 U.S. effectiveness data indicated relatively poor effectiveness of both vaccines, leading CDC in 2015 to no longer prefer LAIV. An age-structured model of influenza transmission and vaccination was developed, which incorporated both direct and indirect protection induced by vaccination. Based on this model, the cost effectiveness of influenza vaccination strategies in children aged 2-8 years in the U.S. was estimated. The base case assumed a mixed vaccination strategy where 33.3% and 66.7% of vaccinated children aged 2-8 years receive LAIV and IIV, respectively. Analyses were performed in 2014-2015. Using published meta-analysis vaccine effectiveness data (83% LAIV and 64% IIV), exclusive LAIV use would be a cost-effective strategy when vaccinating children aged 2-8 years, whereas IIV would not be preferred. However, when 2014-2015 U.S. effectiveness data (0% LAIV and 15% IIV) were used, IIV was likely to be preferred. The cost effectiveness of influenza vaccination in children aged 2-8 years is highly dependent on vaccine effectiveness; the vaccine type with higher effectiveness is preferred. In general, exclusive IIV use is preferred over LAIV use, as long as vaccine effectiveness is higher for IIV than for LAIV. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Novel vaccine development strategies for inducing mucosal immunity

PubMed Central

Fujkuyama, Yoshiko; Tokuhara, Daisuke; Kataoka, Kosuke; Gilbert, Rebekah S; McGhee, Jerry R; Yuki, Yoshikazu; Kiyono, Hiroshi; Fujihashi, Kohtaro

2012-01-01

To develop protective immune responses against mucosal pathogens, the delivery route and adjuvants for vaccination are important. The host, however, strives to maintain mucosal homeostasis by responding to mucosal antigens with tolerance, instead of immune activation. Thus, induction of mucosal immunity through vaccination is a rather difficult task, and potent mucosal adjuvants, vectors or other special delivery systems are often used, especially in the elderly. By taking advantage of the common mucosal immune system, the targeting of mucosal dendritic cells and microfold epithelial cells may facilitate the induction of effective mucosal immunity. Thus, novel routes of immunization and antigen delivery systems also show great potential for the development of effective and safe mucosal vaccines against various pathogens. The purpose of this review is to introduce several recent approaches to induce mucosal immunity to vaccines, with an emphasis on mucosal tissue targeting, new immunization routes and delivery systems. Defining the mechanisms of mucosal vaccines is as important as their efficacy and safety, and in this article, examples of recent approaches, which will likely accelerate progress in mucosal vaccine development, are discussed. PMID:22380827

Good vaccination practice: it all starts with a good vaccine storage temperature.

PubMed

Vangroenweghe, Frédéric

2017-01-01

Recent introduction of strategies to reduce antibiotic use in food animal production implies an increased use of vaccines in order to prevent the economic impact of several important diseases in swine. Good Vaccination Practice (GVP) is an overall approach on the swine farm aiming to obtain maximal efficacy of vaccination through good storage, preparation and finally correct application to the target animals. In order to have a better insight into GVP on swine farms and the vaccine storage conditions, a survey on vaccination practices was performed on a farmers' fair and temperatures in the vaccine storage refrigerators were measured during farm visits over a period of 1 year. The survey revealed that knowledge on GVP, such as vaccine storage and handling, needle management and injection location could be improved. Less than 10% had a thermometer in their vaccine storage refrigerator on the moment of the visit. Temperature measurement revealed that only 71% of the measured refrigerators were in line with the recommended temperature range of +2 °C to +8 °C. Both below +2 °C and above +8 °C temperatures were registered during all seasons of the year. Compliance was lower during summer with an average temperature of 9.2 °C while only 43% of the measured temperatures were within the recommended range. The present study clearly showed the need for continuous education on GVP for swine veterinarians, swine farmers and their farm personnel in general and vaccine storage management in particular. In veterinary medicine, the correct storage of vaccines is crucial since both too low and too high temperatures can provoke damage to specific vaccine types. Adjuvanted killed or subunit vaccines can be damaged (e.g. structure of aluminiumhydroxide in adjuvans) by too low temperatures (below 0 °C), whereas lyophilized live vaccines are susceptible (e.g. loss of vaccine potency) to heat damage by temperatures above +8 °C. In conclusion, knowledge and awareness of GVP

Preferential Targeting of Conserved Gag Regions after Vaccination with a Heterologous DNA Prime-Modified Vaccinia Virus Ankara Boost HIV-1 Vaccine Regimen.

PubMed

Bauer, Asli; Podola, Lilli; Mann, Philipp; Missanga, Marco; Haule, Antelmo; Sudi, Lwitiho; Nilsson, Charlotta; Kaluwa, Bahati; Lueer, Cornelia; Mwakatima, Maria; Munseri, Patricia J; Maboko, Leonard; Robb, Merlin L; Tovanabutra, Sodsai; Kijak, Gustavo; Marovich, Mary; McCormack, Sheena; Joseph, Sarah; Lyamuya, Eligius; Wahren, Britta; Sandström, Eric; Biberfeld, Gunnel; Hoelscher, Michael; Bakari, Muhammad; Kroidl, Arne; Geldmacher, Christof

2017-09-15

given immunogen in prime-boost vaccination strategies is one approach that aims to improve coverage for global virus variants, the immunologic consequences of this strategy have been poorly defined so far. It is unclear whether inclusion of multiple variants in prime-boost vaccination strategies improves recognition of variant viruses by T cells and by which mechanisms this would be achieved, either by improved cross-recognition of multiple variants for a given antigenic region or through preferential targeting of antigenic regions more conserved between prime and boost. Engineering vaccines to induce adaptive immune responses that preferentially target conserved antigenic regions of viral vulnerability might facilitate better immune control after preventive and therapeutic vaccination for HIV and for other variable viruses. Copyright © 2017 American Society for Microbiology.

Increasing Coverage of Appropriate Vaccinations

PubMed Central

Jacob, Verughese; Chattopadhyay, Sajal K.; Hopkins, David P.; Morgan, Jennifer Murphy; Pitan, Adesola A.; Clymer, John

2016-01-01

Context Population-level coverage for immunization against many vaccine-preventable diseases remains below optimal rates in the U.S. The Community Preventive Services Task Force recently recommended several interventions to increase vaccination coverage based on systematic reviews of the evaluation literature. The present study provides the economic results from those reviews. Evidence acquisition A systematic review was conducted (search period, January 1980 through February 2012) to identify economic evaluations of 12 interventions recommended by the Task Force. Evidence was drawn from included studies; estimates were constructed for the population reach of each strategy, cost of implementation, and cost per additional vaccinated person because of the intervention. Analyses were conducted in 2014. Evidence synthesis Reminder systems, whether for clients or providers, were among the lowest-cost strategies to implement and the most cost effective in terms of additional people vaccinated. Strategies involving home visits and combination strategies in community settings were both costly and less cost effective. Strategies based in settings such as schools and managed care organizations that reached the target population achieved additional vaccinations in the middle range of cost effectiveness. Conclusions The interventions recommended by the Task Force differed in reach, cost, and cost effectiveness. This systematic review presents the economic information for 12 effective strategies to increase vaccination coverage that can guide implementers in their choice of interventions to fit their local needs, available resources, and budget. PMID:26847663

Strategies to advance vaccine technologies for resource-poor settings.

PubMed

Kristensen, Debra; Chen, Dexiang

2013-04-18

New vaccine platform and delivery technologies that can have significant positive impacts on the effectiveness, acceptability, and safety of immunizations in developing countries are increasingly available. Although donor support for vaccine technology development is strong, the uptake of proven technologies by the vaccine industry and demand for them by purchasers continues to lag. This article explains the challenges and opportunities associated with accelerating the availability of innovative and beneficial vaccine technologies to meet critical needs in resource-poor settings over the next decade. Progress will require increased dialog between the public and private sectors around vaccine product attributes; establishment of specifications for vaccines that mirror programmatic needs; stronger encouragement of vaccine developers to consider novel technologies early in the product development process; broader facilitation of research and access to technologies through the formation of centers of excellence; the basing of vaccine purchase decisions on immunization systems costs rather than price per dose alone; possible subsidization of early technology adoption costs for vaccine producers that take on the risks of new technologies of importance to the public sector; and the provision of data to purchasers, better enabling them to make informed decisions that take into account the value of specific product attributes. Copyright © 2012 Elsevier Ltd. All rights reserved.

Knowledge, awareness and practices towards seasonal influenza and its vaccine: implications for future vaccination campaigns in Jordan.

PubMed

Abu-Rish, Eman Y; Elayeh, Eman R; Mousa, Lubabah A; Butanji, Yasser K; Albsoul-Younes, Abla M

2016-12-01

Influenza is an underestimated contributor to morbidity and mortality. Population knowledge regarding influenza and its vaccination has a key role in enhancing vaccination coverage. This study aimed to identify the gaps of knowledge among Jordanian population towards influenza and its vaccine, and to identify the major determinants of accepting seasonal influenza vaccine in adults and children in Jordan. This was a cross-sectional study that enrolled 941 randomly selected adults in Amman, Jordan. A four-section questionnaire was used which included questions about the sociodemographic characteristics, knowledge about influenza and the factors that affect seasonal influenza vaccine acceptance and refusal. Only 47.3% of the participants were considered knowledgeable. About half of the participants (51.9%) correctly identified the main influenza preventative measures. Lack of knowledge about the important role of seasonal influenza vaccine in disease prevention was observed. Low vaccination rate (20% of adults) was reported. The most critical barrier against vaccination in adults and children was the concern about the safety and the efficacy of the vaccine, while the most important predictors for future vaccination in adults and children were physician recommendation and government role. In children, the inclusion of the vaccine within the national immunization program was an important determinant of vaccine acceptance. Formulating new strategies to improve the population's level of knowledge, assuring the population about the safety and the efficacy of the vaccine and the inclusion of the vaccine within the national immunization program are the essential factors to enhance vaccination coverage in Jordan. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

HSV-2 Vaccine: Current Status and Insight into Factors for Developing an Efficient Vaccine

PubMed Central

Zhu, Xiao-Peng; Muhammad, Zaka S.; Wang, Jian-Guang; Lin, Wu; Guo, Shi-Kun; Zhang, Wei

2014-01-01

Herpes simplex virus type 2 (HSV-2), a globally sexually transmitted virus, and also one of the main causes of genital ulcer diseases, increases susceptibility to HIV-1. Effective vaccines to prevent HSV-2 infection are not yet available, but are currently being developed. To facilitate this process, the latest progress in development of these vaccines is reviewed in this paper. A summary of the most promising HSV-2 vaccines tested in animals in the last five years is presented, including the main factors, and new ideas for developing an effective vaccine from animal experiments and human clinical trials. Experimental results indicate that future HSV-2 vaccines may depend on a strategy that targets mucosal immunity. Furthermore, estradiol, which increases the effectiveness of vaccines, may be considered as an adjuvant. Therefore, this review is expected to provide possible strategies for development of future HSV-2 vaccines. PMID:24469503

Herpes zoster vaccine: A health economic evaluation for Switzerland

PubMed Central

Blank, Patricia R.; Ademi, Zanfina; Lu, Xiaoyan; Szucs, Thomas D.; Schwenkglenks, Matthias

2017-01-01

ABSTRACT Herpes zoster (HZ) or “shingles” results from a reactivation of the varicella zoster virus (VZV) acquired during primary infection (chickenpox) and surviving in the dorsal root ganglia. In about 20% of cases, a complication occurs, known as post-herpetic neuralgia (PHN). A live attenuated vaccine against VZV is available for the prevention of HZ and subsequent PHN. The present study aims to update an earlier evaluation estimating the cost-effectiveness of the HZ vaccine from a Swiss third party payer perspective. It takes into account updated vaccine prices, a different age cohort, latest clinical data and burden of illness data. A Markov model was developed to simulate the lifetime consequences of vaccinating 15% of the Swiss population aged 65–79 y. Information from sentinel data, official statistics and published literature were used. Endpoints assessed were number of HZ and PHN cases, quality-adjusted life years (QALYs), costs of hospitalizations, consultations and prescriptions. Based on a vaccine price of CHF 162, the vaccination strategy accrued additional costs of CHF 17,720,087 and gained 594 QALYs. The incremental cost-effectiveness ratio (ICER) was CHF 29,814 per QALY gained. Sensitivity analyses showed that the results were most sensitive to epidemiological inputs, utility values, discount rates, duration of vaccine efficacy, and vaccine price. Probabilistic sensitivity analyses indicated a more than 99% chance that the ICER was below 40,000 CHF per QALY. Findings were in line with existing cost-effectiveness analyses of HZ vaccination. This updated study supports the value of an HZ vaccination strategy targeting the Swiss population aged 65–79 y. PMID:28481678

[Seasonal influenza vaccination in children and adolescents. Recommendations of the CAV-AEP for the campaign].

PubMed

Moreno-Pérez, D; Arístegui Fernández, J; Ruiz-Contreras, J; Alvarez García, F J; Merino Moína, M; González-Hachero, J; Corretger Rauet, J M; Hernández-Sampelayo Matos, T; Ortigosa del Castillo, L; Cilleruelo Ortega, M J; Barrio Corrales, F

2012-01-01

The Advisory Committee on Vaccines of the Spanish Association of Paediatrics establishes annual recommendations on influenza vaccination in childhood before the onset of influenza season. Routine influenza vaccination is particularly beneficial when the strategy is aimed at children older than 6 months of age with high-risk conditions and their home contacts. The recommendation of influenza vaccination in health workers with children is also emphasized. Copyright © 2011 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

Rotavirus vaccines

PubMed Central

Yen, Catherine; Tate, Jacqueline E; Hyde, Terri B; Cortese, Margaret M; Lopman, Benjamin A; Jiang, Baoming; Glass, Roger I; Parashar, Umesh D

2014-01-01

Rotavirus is the leading cause of severe diarrhea among children <5 years worldwide. Currently licensed rotavirus vaccines have been efficacious and effective, with many countries reporting substantial declines in diarrheal and rotavirus-specific morbidity and mortality. However, the full public health impact of these vaccines has not been realized. Most countries, including those with the highest disease burden, have not yet introduced rotavirus vaccines into their national immunization programs. Research activities that may help inform vaccine introduction decisions include (1) establishing effectiveness, impact, and safety for rotavirus vaccines in low-income settings; (2) identifying potential strategies to improve performance of oral rotavirus vaccines in developing countries, such as zinc supplementation; and (3) pursuing alternate approaches to oral vaccines, such as parenteral immunization. Policy- and program-level barriers, such as financial implications of new vaccine introductions, should be addressed to ensure that countries are able to make informed decisions regarding rotavirus vaccine introduction. PMID:24755452

Primary prevention and vaccination for penile cancer

PubMed Central

Barod, Ravi; Hegarty, Paul K.; Minhas, Suks

2013-01-01

The outcome of penile cancer is proportional to the stage at presentation. Strategies aimed at primary prevention would have a clear advantage, both for the individual and in terms of health economics. A number of preventative measures could be employed, including circumcision, smoking cessation, education on hygiene and human papillomavirus (HPV) prevention. There is a high prevalence of HPV infection associated with penile cancer worldwide. The recent development of HPV vaccines has facilitated interest in their use for the prevention of penile cancer. In this article we review the literature surrounding penile cancer prevention and HPV vaccination in men. PMID:23730331

'Communicate to vaccinate' (COMMVAC). building evidence for improving communication about childhood vaccinations in low- and middle-income countries: protocol for a programme of research.

PubMed

Lewin, Simon; Hill, Sophie; Abdullahi, Leyla H; de Castro Freire, Sara Bensaude; Bosch-Capblanch, Xavier; Glenton, Claire; Hussey, Gregory D; Jones, Catherine M; Kaufman, Jessica; Lin, Vivian; Mahomed, Hassan; Rhoda, Linda; Robinson, Priscilla; Waggie, Zainab; Willis, Natalie; Wiysonge, Charles S

2011-12-02

Effective provider-parent communication can improve childhood vaccination uptake and strengthen immunisation services in low- and middle-income countries (LMICs). Building capacity to improve communication strategies has been neglected. Rigorous research exists but is not readily found or applicable to LMICs, making it difficult for policy makers to use it to inform vaccination policies and practice.The aim of this project is to build research knowledge and capacity to use evidence-based strategies for improving communication about childhood vaccinations with parents and communities in LMICs. This project is a mixed methods study with six sub-studies. In sub-study one, we will develop a systematic map of provider-parent communication interventions for childhood vaccinations by screening and extracting data from relevant literature. This map will inform sub-study two, in which we will develop a taxonomy of interventions to improve provider-parent communication around childhood vaccination. In sub-study three, the taxonomy will be populated with trial citations to create an evidence map, which will also identify how evidence is linked to communication barriers regarding vaccination. In the project's fourth sub-study, we will present the interventions map, taxonomy, and evidence map to international stakeholders to identify high-priority topics for systematic reviews of interventions to improve parent-provider communication for childhood vaccination. We will produce systematic reviews of the effects of high-priority interventions in the fifth sub-study. In the sixth and final sub-study of the project, evidence from the systematic reviews will be translated into accessible formats and messages for dissemination to LMICs. This project combines evidence mapping, conceptual and taxonomy development, priority setting, systematic reviews, and knowledge transfer. It will build and share concepts, terms, evidence, and resources to aid the development of communication

Mycobacterium tuberculosis: approach to development of improved strategies for disease control through vaccination and immunodiagnosis.

PubMed

Mirlekar, B; Pathak, S; Pathade, G

2013-01-01

Tuberculosis is a major health problem throughout the world causing large number of deaths, more than that from any other single infectious disease. Estimates till date ascertain the fact that Tuberculosis (TB) is continuing to be the leading cause of death worldwide. The infection from single infectious agent Mycobacterium tuberculosis is killing about 3 million individuals every year and accounts for around 18.5% of all deaths in adults between the age group of 15 and 65. An average of 1.79 billion people, which constitutes roughly one-third of the world's population, is infected with the causative agent M. tuberculosis and is at risk of developing the disease. This situation highlights the relative shortcomings of the current treatment and diagnosis strategies for TB and the limited effectiveness of public health systems, particularly in resource-poor countries where the main TB burden lies. The timely identification of persons infected with Mycobacterium tuberculosis and rapid laboratory confirmation of tuberculosis are two key factors for the treatment and prevention of the disease. Novel molecular assays for diagnosis and drug susceptibility testing offer several potential advantages over the above methods including faster turnaround times, very sensitive and specific detection of nucleic acids, and minimal, or possibly no, prior culture. The need for new technologies for rapid diagnosis of tuberculosis is clear. Most studies of mycobacterial immunity attributes focus on proliferation of T cells, production of cytokines and cytolytic activity. A proper vaccine for tuberculosis can be developed by using a combination of antigens and adjuvants capable of inducing appropriate and long-lasting T cell immunity. Development of new vaccines against TB should include some important aspects learned from BCG use such as mucosal routes of immunization; revaccination of BCG immunized subjects, booster immunization and prime-boost strategy with wild-type BCG, and other

A model-based economic analysis of pre-pandemic influenza vaccination cost-effectiveness

PubMed Central

2014-01-01

Background A vaccine matched to a newly emerged pandemic influenza virus would require a production time of at least 6 months with current proven techniques, and so could only be used reactively after the peak of the pandemic. A pre-pandemic vaccine, although probably having lower efficacy, could be produced and used pre-emptively. While several previous studies have investigated the cost effectiveness of pre-emptive vaccination strategies, they have not been directly compared to realistic reactive vaccination strategies. Methods An individual-based simulation model of ~30,000 people was used to examine a pre-emptive vaccination strategy, assuming vaccination conducted prior to a pandemic using a low-efficacy vaccine. A reactive vaccination strategy, assuming a 6-month delay between pandemic emergence and availability of a high-efficacy vaccine, was also modelled. Social distancing and antiviral interventions were examined in combination with these alternative vaccination strategies. Moderate and severe pandemics were examined, based on estimates of transmissibility and clinical severity of the 1957 and 1918 pandemics respectively, and the cost effectiveness of each strategy was evaluated. Results Provided that a pre-pandemic vaccine achieved at least 30% efficacy, pre-emptive vaccination strategies were found to be more cost effective when compared to reactive vaccination strategies. Reactive vaccination coupled with sustained social distancing and antiviral interventions was found to be as effective at saving lives as pre-emptive vaccination coupled with limited duration social distancing and antiviral use, with both strategies saving approximately 420 life-years per 10,000 population for a moderate pandemic with a basic reproduction number of 1.9 and case fatality rate of 0.25%. Reactive vaccination was however more costly due to larger productivity losses incurred by sustained social distancing, costing $8 million per 10,000 population ($19,074/LYS) versus $6

A model-based economic analysis of pre-pandemic influenza vaccination cost-effectiveness.

PubMed

Halder, Nilimesh; Kelso, Joel K; Milne, George J

2014-05-16

A vaccine matched to a newly emerged pandemic influenza virus would require a production time of at least 6 months with current proven techniques, and so could only be used reactively after the peak of the pandemic. A pre-pandemic vaccine, although probably having lower efficacy, could be produced and used pre-emptively. While several previous studies have investigated the cost effectiveness of pre-emptive vaccination strategies, they have not been directly compared to realistic reactive vaccination strategies. An individual-based simulation model of ~30,000 people was used to examine a pre-emptive vaccination strategy, assuming vaccination conducted prior to a pandemic using a low-efficacy vaccine. A reactive vaccination strategy, assuming a 6-month delay between pandemic emergence and availability of a high-efficacy vaccine, was also modelled. Social distancing and antiviral interventions were examined in combination with these alternative vaccination strategies. Moderate and severe pandemics were examined, based on estimates of transmissibility and clinical severity of the 1957 and 1918 pandemics respectively, and the cost effectiveness of each strategy was evaluated. Provided that a pre-pandemic vaccine achieved at least 30% efficacy, pre-emptive vaccination strategies were found to be more cost effective when compared to reactive vaccination strategies. Reactive vaccination coupled with sustained social distancing and antiviral interventions was found to be as effective at saving lives as pre-emptive vaccination coupled with limited duration social distancing and antiviral use, with both strategies saving approximately 420 life-years per 10,000 population for a moderate pandemic with a basic reproduction number of 1.9 and case fatality rate of 0.25%. Reactive vaccination was however more costly due to larger productivity losses incurred by sustained social distancing, costing $8 million per 10,000 population ($19,074/LYS) versus $6.8 million per 10

An epidemiological model with vaccination strategies

NASA Astrophysics Data System (ADS)

Prates, Dérek B.; Silva, Jaqueline M.; Gomes, Jessica L.; Kritz, Maurício V.

2016-06-01

Mathematical models can be widely found in the literature describing epidemics. The epidemical models that use differential equations to represent mathematically such description are especially sensible to parameters. This work analyze a variation of the SIR model when applied to a epidemic scenario including several aspects, as constant vaccination, pulse vaccination, seasonality, cross-immunity factor, birth and dead rate. The analysis and results are performed through numerical solutions of the model and a special attention is given to the discussion generated by the paramenters variation.

Human papillomavirus vaccines and vaccine implementation.

PubMed

de Sanjosé, Silvia; Alemany, Laia; Castellsagué, Xavier; Bosch, F Xavier

2008-11-01

Countries are now challenged by the rapid development of vaccines aimed at the primary prevention of infections. In the years to come, several vaccines will need to be considered as potential candidates in routine immunization programs. Recently, two new vaccines against two/four types of human papillomavirus (HPV) have been commercialized. Bivalent HPV 16 and 18 (Cervarix) and quadrivalent HPV 6, 11, 16 and 18 (Gardasil) vaccines are now extensively used in some countries. These vaccines will prevent infection and long-running complications, such as cervical cancer, other HPV-related cancers and genital warts (for the quadrivalent vaccine). The beneficial effect of these vaccines will be largely observed in women. This article summarizes the burden of HPV preventable disease worldwide and briefly describes the impact of secondary prevention and the most relevant aspects of the current available vaccines, their efficacy and safety. Finally, some major aspects that are likely to impact the introduction of these vaccines around the world are outlined, with particular emphasis on developing countries.

Pneumococcal vaccine targeting strategy for older adults: customized risk profiling.

PubMed

Balicer, Ran D; Cohen, Chandra J; Leibowitz, Morton; Feldman, Becca S; Brufman, Ilan; Roberts, Craig; Hoshen, Moshe

2014-02-12

Current pneumococcal vaccine campaigns take a broad, primarily age-based approach to immunization targeting, overlooking many clinical and administrative considerations necessary in disease prevention and resource planning for specific patient populations. We aim to demonstrate the utility of a population-specific predictive model for hospital-treated pneumonia to direct effective vaccine targeting. Data was extracted for 1,053,435 members of an Israeli HMO, age 50 and older, during the study period 2008-2010. We developed and validated a logistic regression model to predict hospital-treated pneumonia using training and test samples, including a set of standard and population-specific risk factors. The model's predictive value was tested for prospectively identifying cases of pneumonia and invasive pneumococcal disease (IPD), and was compared to the existing international paradigm for patient immunization targeting. In a multivariate regression, age, co-morbidity burden and previous pneumonia events were most strongly positively associated with hospital-treated pneumonia. The model predicting hospital-treated pneumonia yielded a c-statistic of 0.80. Utilizing the predictive model, the top 17% highest-risk within the study validation population were targeted to detect 54% of those members who were subsequently treated for hospitalized pneumonia in the follow up period. The high-risk population identified through this model included 46% of the follow-up year's IPD cases, and 27% of community-treated pneumonia cases. These outcomes were compared with international guidelines for risk for pneumococcal diseases that accurately identified only 35% of hospitalized pneumonia, 41% of IPD cases and 21% of community-treated pneumonia. We demonstrate that a customized model for vaccine targeting performs better than international guidelines, and therefore, risk modeling may allow for more precise vaccine targeting and resource allocation than current national and international

Knowledge, attitude, and uptake related to human papillomavirus vaccination among young women in Germany recruited via a social media site.

PubMed

Remschmidt, Cornelius; Walter, Dietmar; Schmich, Patrick; Wetzstein, Matthias; Deleré, Yvonne; Wichmann, Ole

2014-01-01

Many industrialized countries have introduced human papillomavirus (HPV) vaccination of young women, but vaccine uptake often remains suboptimal. This study aimed to investigate whether a social media site like Facebook is an appropriate tool to assess knowledge, attitude and uptake related to HPV vaccination in young women in Germany. Between December 2012 and January 2013 two different targeting strategies were implemented on Facebook, providing a link to an online questionnaire. Advertisements were displayed to female Facebook users aged 18-25 years living in Germany. During the simple targeting strategy, advertisements comprised health-related images along with various short titles and text messages. During the focused strategy, advertisements were targeted to users who in addition had certain fashion brands or pop stars listed on their profiles. The targeting strategies were compared with respect to participant characteristics. Univariate and multivariate analyses were used to identify factors associated with HPV vaccine uptake. A total of 1161 women participated. The two targeting strategies resulted in significant differences regarding educational status and migrant background. Overall, awareness of HPV was high, but only 53% received at least one vaccine dose. In multivariate analysis, HPV vaccine uptake was independently associated with a physician's recommendation and trust in vaccine effectiveness. Concerns of adverse effects were negatively associated with vaccine uptake. Social network recruitment permits fast and convenient access to young people. Sample characteristics can be manipulated by adjusting targeting strategies. There is further need for promoting knowledge of HPV vaccination among young women. Physicians have a major role in the vaccination decision-making process of young women.

Clinical and economic impact of herpes zoster vaccination in elderly in Italy.

PubMed

Boccalini, Sara; Alicino, Cristiano; Martinelli, Domenico; Bechini, Angela; Tiscione, Emilia; Pellizzari, Barbara; Prato, Rosa; Icardi, Giancarlo; Iannazzo, Stefania; Bonanni, Paolo

2017-02-01

Herpes zoster (HZ) is a very relevant pathology among elderly people (≥ 60 years of age), with a considerable disease burden and loss of quality of life. In the last years a new vaccine against HZ became available in Italy. Therefore, the Italian decision makers are now confronted with the decision whether that vaccination should be implemented. Pharmaco-economic analyses represent useful tools to value the feasibility of new immunization programs and their sustainability. To this aim, an ad hoc population model was developed in order to value the clinical and economic impact of HZ vaccination program for the elderly in Italy. Particularly, different immunization scenarios were modeled: vaccination of 60 years-old subjects (single cohort strategy), simultaneous vaccination of people aged 60 and 65 years (double cohort strategy) and, lastly, immunization of people aged 60, 65 and 70 years (triple cohort strategy), thus leading to the vaccination of 5, 10 and 15 cohorts during the first 5 years of the program. The mathematical model valued the clinical impact of vaccination on the number of HZ, post-herpetic neuralgia (PHN) and ophthalmic HZ. The results of the analysis show that, in Italy, a cohort-based HZ vaccination program in elderly could have a relevant impact on the reduction of clinical cases and a favorable economic profile for the National Health Service (NHS), as already foreseen in other countries. In addition, further benefits could be obtained when extending the study period beyond the 5-year horizon of our analysis.

[Vaccination among students in grades 6-10, 2011 - a comparison of German states: need for action for a targeted nationwide immunisation strategy].

PubMed

Ellsäßer, G; Trost-Brinkhues, G

2013-11-01

In Germany, surveillance of the population's immunisation is only mandatory for school beginners, not for adolescents. Therefore, no current data are available from the public health service related to the immunisation of adolescents. Also lacking are nationwide monitoring data regarding HPV vaccination among girls aged 12-18 years and the meningococcal C vaccination, both recently introduced by the German Standing Committee on Vaccination (STIKO) in 2009 and 2006, respectively. The present research and analysis therefore aims to determine which German states perform a monitoring of the vaccination status of adolescents, how immunisation rates differ across German states and what need for action, in terms of a nationwide immunisation strategy, can be derived. A systematic survey of vaccination coverage among students in grades 6-10 (age group 12-16 years) for the school year 2010/11 was undertaken. The defined documentation standard is based on the standard vaccinations for children and adolescents according to STIKO, requiring complete primary immunization (PI) and the number of booster vaccinations. In the analysis, 8 of 16 states were included, due to lack of data for the remaining states. In total, the public health service -examined 157,599 school children in 8 German states and checked 103,250 vaccination certificates (on average 68.1%, range 54.9-85.2%). The implementation of the booster vaccination among students in grades 6-10 proved to be insufficient. The 2-dose measles vaccination, required by the WHO for 95% of the population, was only nearly achieved by 2 of 8 German states -(Saxony-Anhalt, Brandenburg). The effects of insufficient immunisation coverage are shown by, for example, a higher measles incidence rate in children under 15 years and a persisting peak of pertussis incidence in 10- to 15-year-olds. The meningococcal C vaccination, introduced in 2006, was insufficiently taken up by students and very differently implemented among the 8 -German

Clinical and economic impact of various strategies for varicella immunity screening and vaccination of health care personnel.

PubMed

Baracco, G J; Eisert, S; Saavedra, S; Hirsch, P; Marin, M; Ortega-Sanchez, I R

2015-10-01

Exposure to patients with varicella or herpes zoster causes considerable disruption to a health care facility's operations and has a significant health and economic impact. However, practices related to screening for immunity and immunization of health care personnel (HCP) for varicella vary widely. A decision tree model was built to evaluate the cost-effectiveness of 8 different strategies of screening and vaccinating HCP for varicella. The outcomes are presented as probability of acquiring varicella, economic impact of varicella per employee per year, and cost to prevent additional cases of varicella. Monte Carlo simulations and 1-way sensitivity analyses were performed to address the uncertainties inherent to the model. Alternative epidemiologic and technologic scenarios were also analyzed. Performing a clinical screening followed by serologic testing of HCP with negative history diminished the cost impact of varicella by >99% compared with not having a program. Vaccinating HCP with negative screen cost approximately $50,000 per case of varicella prevented at the current level of U.S. population immunity, but was projected to be cost-saving at 92% or lower immunity prevalence. Improving vaccine acceptance rates and using highly sensitive assays also optimize cost-effectiveness. Strategies relying on screening and vaccinating HCP for varicella on employment were shown to be cost-effective for health care facilities and are consistent with current national guidelines for varicella prevention. Published by Elsevier Inc.

[Anti-influenza vaccination in animals].

PubMed

Bublot, M

2009-01-01

Until recently, Influenza was considered as a veterinary problem in avian, swine and horse only. New influenza strains able to infect and cause a disease in dogs and cats emerged these last six years. The most widely used influenza veterinary vaccines are the inactivated adjuvanted vaccines which are based on whole or split virus. New technologies have allowed the development of new generation vaccines including modified-live and vector vaccines. Modified-live influenza vaccines are available for horses only but they are in development in other species. Vector vaccines are already in use in chickens (replicative fowlpox vector) and in horses (non-replicative canarypox vector). These vaccines induce a rapid cellular and humoral immunity. Experimental studies have also shown that these vector vaccines are protective in other domestic species. These vector vaccines are compatible with the "DIVA" strategy which consists in differentiating infected from vaccinated animals and which allows disease eradication. The successive use of vector and inactivated vaccines (heterologous "prime-boost") induces a superior protective immunity in domestic poultry and constitutes a promising strategy for the control of H5N1 infection.

Antibody-based vaccine strategies against intracellular pathogens.

PubMed

Casadevall, Arturo

2018-04-25

Historically, antibody-mediated immunity was considered effective against toxins, extracellular pathogens and viruses, while control of intracellular pathogens was the domain of cellular immunity. However, numerous observations in recent decades have conclusively shown that antibody can protect against intracellular pathogens. This paradigmatic shift has tremendous implications for immunology and vaccine design. For immunology the observation that antibody can protect against intracellular pathogens has led to the discovery of new mechanisms of antibody action. For vaccine design the knowledge that humoral immunity can be effective in protection means that the knowledge acquired in more than a century of antibody studies can be applied to make new vaccines against this class of pathogens. Copyright © 2018 Elsevier Ltd. All rights reserved.

Communicating with parents about vaccination: a framework for health professionals.

PubMed

Leask, Julie; Kinnersley, Paul; Jackson, Cath; Cheater, Francine; Bedford, Helen; Rowles, Greg

2012-09-21

A critical factor shaping parental attitudes to vaccination is the parent's interactions with health professionals. An effective interaction can address the concerns of vaccine supportive parents and motivate a hesitant parent towards vaccine acceptance. Poor communication can contribute to rejection of vaccinations or dissatisfaction with care. We sought to provide a framework for health professionals when communicating with parents about vaccination. Literature review to identify a spectrum of parent attitudes or 'positions' on childhood vaccination with estimates of the proportion of each group based on population studies. Development of a framework related to each parental position with determination of key indicators, goals and strategies based on communication science, motivational interviewing and valid consent principles. Five distinct parental groups were identified: the 'unquestioning acceptor' (30-40%), the 'cautious acceptor' (25-35%); the 'hesitant' (20-30%); the 'late or selective vaccinator' (2-27%); and the 'refuser' of all vaccines (<2%). The goals of the encounter with each group will vary, depending on the parents' readiness to vaccinate. In all encounters, health professionals should build rapport, accept questions and concerns, and facilitate valid consent. For the hesitant, late or selective vaccinators, or refusers, strategies should include use of a guiding style and eliciting the parent's own motivations to vaccinate while, avoiding excessive persuasion and adversarial debates. It may be necessary to book another appointment or offer attendance at a specialised adverse events clinic. Good information resources should also be used. Health professionals have a central role in maintaining public trust in vaccination, including addressing parents' concerns. These recommendations are tailored to specific parental positions on vaccination and provide a structured approach to assist professionals. They advocate respectful interactions that aim to

Manipulating Google's Knowledge Graph Box to Counter Biased Information Processing During an Online Search on Vaccination: Application of a Technological Debiasing Strategy.

PubMed

Ludolph, Ramona; Allam, Ahmed; Schulz, Peter J

2016-06-02

One of people's major motives for going online is the search for health-related information. Most consumers start their search with a general search engine but are unaware of the fact that its sorting and ranking criteria do not mirror information quality. This misconception can lead to distorted search outcomes, especially when the information processing is characterized by heuristic principles and resulting cognitive biases instead of a systematic elaboration. As vaccination opponents are vocal on the Web, the chance of encountering their non‒evidence-based views on immunization is high. Therefore, biased information processing in this context can cause subsequent impaired judgment and decision making. A technological debiasing strategy could counter this by changing people's search environment. This study aims at testing a technological debiasing strategy to reduce the negative effects of biased information processing when using a general search engine on people's vaccination-related knowledge and attitudes. This strategy is to manipulate the content of Google's knowledge graph box, which is integrated in the search interface and provides basic information about the search topic. A full 3x2 factorial, posttest-only design was employed with availability of basic factual information (comprehensible vs hardly comprehensible vs not present) as the first factor and a warning message as the second factor of experimental manipulation. Outcome variables were the evaluation of the knowledge graph box, vaccination-related knowledge, as well as beliefs and attitudes toward vaccination, as represented by three latent variables emerged from an exploratory factor analysis. Two-way analysis of variance revealed a significant main effect of availability of basic information in the knowledge graph box on participants' vaccination knowledge scores (F2,273=4.86, P=.01), skepticism/fear of vaccination side effects (F2,273=3.5, P=.03), and perceived information quality (F2

Vaccine chronicle in Japan.

PubMed

Nakayama, Tetsuo

2013-10-01

The concept of immunization was started in Japan in 1849 when Jenner's cowpox vaccine seed was introduced, and the current immunization law was stipulated in 1948. There have been two turning points for amendments to the immunization law: the compensation remedy for vaccine-associated adverse events in 1976, and the concept of private vaccination in 1994. In 1992, the regional Court of Tokyo, not the Supreme Court, decided the governmental responsibility on vaccine-associated adverse events, which caused the stagnation of vaccine development. In 2010, many universal vaccines became available as the recommended vaccines, but several vaccines, including mumps, zoster, hepatitis B, and rota vaccines, are still voluntary vaccines, not universal routine applications. In this report, immunization strategies and vaccine development are reviewed for each vaccine item and future vaccine concerns are discussed.

Diagnosing avian influenza infection in vaccinated populations by systems for differentiating infected from vaccinated animals (DIVA).

PubMed

Capua, I; Cattoli, G

2007-01-01

Vaccination against avian influenza is recommended as a tool to support control measures in countries affected by avian influenza. Vaccination is known to increase the resistance of susceptible birds to infection and also to reduce shedding; however, it does not always prevent infection. Vaccinated infected flocks can therefore be a source of infection and thus be responsible for the perpetuation of infection. To avoid the spread of infection in a vaccinated population, immunization strategies must allow differentiation of infected from vaccinated animals (DIVA), combined with an appropriate monitoring system. Vaccinated exposed flocks must be identified and managed by restriction policies that include controlled marketing and stamping-out. Several vaccines and diagnostic tests to detect infection in vaccinated populations are available, the tests having various properties and characteristics. In order to achieve eradication, the most appropriate DIVA vaccination strategy must be identified and an appropriate monitoring programme be designed, taking into account risk factors, the epidemiological situation and the socioeconomic implications of the policy.

Human papillomavirus vaccination: what is the best choice? A comparison of 16 strategies by means of a decisional model.

PubMed

Gasparini, R; Amicizia, D; Manfredi, P; Ansaldi, F; Lucioni, C; Gallelli, G; Panatto, D

2009-06-01

Some European countries decided to include human papillomavirus (HPV) vaccines in national immunization schedules. In order to help decision makers choose the best vaccination policy for females, a decisional model has been developed. The study was performed from the National Health Service perspective. Several hypotheses of multi-cohort vaccination policies were compared. 'Potentially avoidable infections' were chosen as the outcome. The model envisioned a short-term scenario (2008-2011). The best policy was that of vaccinating 12-year-olds and, a year later, those aged 14-16 years; the most expensive strategy was that of vaccinating 12-year-old females and, after 1 year, vaccinating those aged 15, 18 and 25 years. The sensitivity analysis showed that coverage rate has a great effect on the cost of avoidable infections. The study offers stake-holders an important datum-point for the choice of the best HPV policy vaccination in the short term. Indeed, it could generate interesting savings for the National Health Service and a rapid HPV immunization of young girls.

Strategies for new and improved vaccines against ticks and tick-borne diseases.

PubMed

de la Fuente, J; Kopáček, P; Lew-Tabor, A; Maritz-Olivier, C

2016-12-01

Ticks infest a variety of animal species and transmit pathogens causing disease in both humans and animals worldwide. Tick-host-pathogen interactions have evolved through dynamic processes that accommodated the genetic traits of the hosts, pathogens transmitted and the vector tick species that mediate their development and survival. New approaches for tick control are dependent on defining molecular interactions between hosts, ticks and pathogens to allow for discovery of key molecules that could be tested in vaccines or new generation therapeutics for intervention of tick-pathogen cycles. Currently, tick vaccines constitute an effective and environmentally sound approach for the control of ticks and the transmission of the associated tick-borne diseases. New candidate protective antigens will most likely be identified by focusing on proteins with relevant biological function in the feeding, reproduction, development, immune response, subversion of host immunity of the tick vector and/or molecules vital for pathogen infection and transmission. This review addresses different approaches and strategies used for the discovery of protective antigens, including focusing on relevant tick biological functions and proteins, reverse genetics, vaccinomics and tick protein evolution and interactomics. New and improved tick vaccines will most likely contain multiple antigens to control tick infestations and pathogen infection and transmission. © 2016 John Wiley & Sons Ltd.

Factors affecting the implementation of childhood vaccination communication strategies in Nigeria: a qualitative study.

PubMed

Oku, Afiong; Oyo-Ita, Angela; Glenton, Claire; Fretheim, Atle; Eteng, Glory; Ames, Heather; Muloliwa, Artur; Kaufman, Jessica; Hill, Sophie; Cliff, Julie; Cartier, Yuri; Bosch-Capblanch, Xavier; Rada, Gabriel; Lewin, Simon

2017-02-15

The role of health communication in vaccination programmes cannot be overemphasized: it has contributed significantly to creating and sustaining demand for vaccination services and improving vaccination coverage. In Nigeria, numerous communication approaches have been deployed but these interventions are not without challenges. We therefore aimed to explore factors affecting the delivery of vaccination communication in Nigeria. We used a qualitative approach and conducted the study in two states: Bauchi and Cross River States in northern and southern Nigeria respectively. We identified factors affecting the implementation of communication interventions through interviews with relevant stakeholders involved in vaccination communication in the health services. We also reviewed relevant documents. Data generated were transcribed verbatim and analysed using thematic analysis. We used the SURE framework to organise the identified factors (barriers and facilitators) affecting vaccination communication delivery. We then grouped these into health systems and community level factors. Some of the commonly reported health system barriers amongst stakeholders interviewed included: funding constraints, human resource factors (health worker shortages, training deficiencies, poor attitude of health workers and vaccination teams), inadequate infrastructure and equipment and weak political will. Community level factors included the attitudes of community stakeholders and of parents and caregivers. We also identified factors that appeared to facilitate communication activities. These included political support, engagement of traditional and religious institutions and the use of organised communication committees. Communication activities are a crucial element of immunization programmes. It is therefore important for policy makers and programme managers to understand the barriers and facilitators affecting the delivery of vaccination communication so as to be able to implement

European Vaccine Initiative: lessons from developing malaria vaccines.

PubMed

Geels, Mark J; Imoukhuede, Egeruan B; Imbault, Nathalie; van Schooten, Harry; McWade, Terry; Troye-Blomberg, Marita; Dobbelaer, Roland; Craig, Alister G; Leroy, Odile

2011-12-01

For over 10 years, the European Vaccine Initiative (EVI; European Malaria Vaccine Initiative until 2009) has contributed to the development of 24 malaria candidate vaccine antigens with 13 vaccine candidates being advanced into Phase I clinical trials, two of which have been transitioned for further clinical development in sub-Saharan Africa. Since its inception the EVI organization has operated as a funding agency, but with a clear service-oriented strategy. The scientific successes and difficulties encountered during these years and how these efforts have led to standardization and harmonization in vaccine development through large-scale European consortia are discussed. In the future, the EVI will remain instrumental in the pharmaceutical and clinical development of vaccines against 'diseases of poverty' with a continued focus on malaria. EVI will continue to focus on funding and managing preclinical evaluation up to Phase I/II clinical trials and strengthening the vaccine-development infrastructure in Europe, albeit with a global orientation.

Costs of Neisseria meningitidis Group A Disease and Economic Impact of Vaccination in Burkina Faso

PubMed Central

Colombini, Anaïs; Trotter, Caroline; Madrid, Yvette; Karachaliou, Andromachi; Preziosi, Marie-Pierre

2015-01-01

Background. Five years since the successful introduction of MenAfriVac in a mass vaccination campaign targeting 1- to 29-year-olds in Burkina Faso, consideration must be given to the optimal strategies for sustaining population protection. This study aims to estimate the economic impact of a range of vaccination strategies in Burkina Faso. Methods. We performed a cost-of-illness study, comparing different vaccination scenarios in terms of costs to both households and health systems over a 26-year time horizon. These scenarios are (1) reactive vaccination campaign (baseline comparator); (2) preventive vaccination campaign; (3) routine immunization at 9 months; and (4) a combination of routine and an initial catchup campaign of children under 5. Costs were estimated from a literature review, which included unpublished programmatic documents and peer-reviewed publications. The future disease burden for each vaccination strategy was predicted using a dynamic transmission model of group A Neisseria meningitidis. Results. From 2010 to 2014, the total costs associated with the preventive campaign targeting 1- to 29-year-olds with MenAfriVac were similar to the estimated costs of the reactive vaccination strategy (approximately 10 million US dollars [USD]). Between 2015 and 2035, routine immunization with or without a catch-up campaign of 1- to 4-year-olds is cost saving compared with the reactive strategy, both with and without discounting costs and cases. Most of the savings are accrued from lower costs of case management and household costs resulting from a lower burden of disease. After the initial investment in the preventive strategy, 1 USD invested in the routine strategy saves an additional 1.3 USD compared to the reactive strategy. Conclusions. Prevention strategies using MenAfriVac will be significantly cost saving in Burkina Faso, both for the health system and for households, compared with the reactive strategy. This will protect households from

Cost effectiveness evaluation of a rotavirus vaccination program in Argentina.

PubMed

Martí, Sebastián García; Alcaraz, Andrea; Valanzasca, Pilar; McMullen, Mercedes; Standaert, Baudouin; Garay, Ulises; Lepetic, Alejandro; Gomez, Jorge

2015-10-13

Rotavirus diarrhea is one of the most important vaccine-preventable causes of severe diarrhea in children worldwide. There are two live-attenuated virus vaccines licensed, Rotarix (RV1) a monovalent vaccine by GlaxoSmithKline and a pentavalent vaccine, RotaTeq(RV5), by Merck & Co., with similar results. This study aim was to evaluate the cost-effectiveness of the utilization of RV1 compared with RV5 in Argentina. A deterministic Markov model based on the lifetime follow up of a static cohort was used. Quality Adjusted Life Years (QALYs) as a measure of results, the perspective of the health care system and a 5% discount rate for health benefits and costs has been used. A review of the literature to obtain epidemiologic and resources utilization of rotavirus diarrhea was performed. The sources used to estimate epidemiologic parameters were the National Health Surveillance System, the national mortality statistics and national database of hospital discharges records. Costs were obtained from different health subsectors and are expressed in local currency. Both vaccination alternatives were less costly and more effective than the strategy without vaccination (total costs $ 69,700,645 and 2575 total QALYs lost). When comparing RV1 vs. RV5, RV1 was less expensive ($ 60,174,508 vs. $ 67,545,991 total costs) and more effective (1105 vs. 1213 total QALYs lost) than RV5, RV1 being therefore a dominating strategy. Probabilistic sensitivity analysis showed results to be robust with a 100% probability of being cost-effective at a WTP threshold of 1 GDP per capita when comparing the RV1 vs. no vaccination. Both RV1 and RV5 schedules dominate the no vaccination strategy and RV5 was dominated by RV1. This information is a valuable input regarding the incorporation of this kind of vaccines into the national vaccination programs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sustainable vaccine development: a vaccine manufacturer's perspective.

PubMed

Rappuoli, Rino; Hanon, Emmanuel

2018-05-08

Vaccination remains the most cost-effective public health intervention after clean water, and the benefits impressively outweigh the costs. The efforts needed to fulfill the steadily growing demands for next-generation and novel vaccines designed for emerging pathogens and new indications are only realizable in a sustainable business model. Vaccine development can be fast-tracked through strengthening international collaborations, and the continuous innovation of technologies to accelerate their design, development, and manufacturing. However, these processes should be supported by a balanced project portfolio, and by managing sustainable vaccine procurement strategies for different types of markets. Collectively this will allow a gradual shift to a more streamlined and profitable vaccine production, which can significantly contribute to the worldwide effort to shape global health. Copyright © 2018 GlaxoSmithKine Biologicals SA. Published by Elsevier Ltd.. All rights reserved.

Communicating with parents about vaccination: a framework for health professionals

PubMed Central

2012-01-01

Background A critical factor shaping parental attitudes to vaccination is the parent’s interactions with health professionals. An effective interaction can address the concerns of vaccine supportive parents and motivate a hesitant parent towards vaccine acceptance. Poor communication can contribute to rejection of vaccinations or dissatisfaction with care. We sought to provide a framework for health professionals when communicating with parents about vaccination. Methods Literature review to identify a spectrum of parent attitudes or ‘positions’ on childhood vaccination with estimates of the proportion of each group based on population studies. Development of a framework related to each parental position with determination of key indicators, goals and strategies based on communication science, motivational interviewing and valid consent principles. Results Five distinct parental groups were identified: the ‘unquestioning acceptor’ (30–40%), the ‘cautious acceptor’ (25–35%); the ‘hesitant’ (20–30%); the ‘late or selective vaccinator’ (2–27%); and the ‘refuser’ of all vaccines (<2%). The goals of the encounter with each group will vary, depending on the parents’ readiness to vaccinate. In all encounters, health professionals should build rapport, accept questions and concerns, and facilitate valid consent. For the hesitant, late or selective vaccinators, or refusers, strategies should include use of a guiding style and eliciting the parent’s own motivations to vaccinate while, avoiding excessive persuasion and adversarial debates. It may be necessary to book another appointment or offer attendance at a specialised adverse events clinic. Good information resources should also be used. Conclusions Health professionals have a central role in maintaining public trust in vaccination, including addressing parents’ concerns. These recommendations are tailored to specific parental positions on vaccination and provide a structured

Working towards dengue as a vaccine-preventable disease: challenges and opportunities.

PubMed

Shrivastava, Ambuj; Tripathi, Nagesh K; Dash, Paban K; Parida, Manmohan

2017-10-01

Dengue is an emerging viral disease that affects the human population around the globe. Recent advancements in dengue virus research have opened new avenues for the development of vaccines against dengue. The development of a vaccine against dengue is a challenging task because any of the four serotypes of dengue viruses can cause disease. The development of a dengue vaccine aims to provide balanced protection against all the serotypes. Several dengue vaccine candidates are in the developmental stages such as inactivated, live attenuated, recombinant subunit, and plasmid DNA vaccines. Area covered: The authors provide an overview of the progress made in the development of much needed dengue vaccines. The authors include their expert opinion and their perspectives for future developments. Expert opinion: Human trials of a live attenuated tetravalent chimeric vaccine have clearly demonstrated its potential as a dengue vaccine. Other vaccine candidate molecules such as DENVax, a recombinant chimeric vaccine andTetraVax, are at different stages of development at this time. The authors believe that the novel strategies for testing and improving the immune response of vaccine candidates in humans will eventually lead to the development of a successful dengue vaccine in future.

Hand, foot and mouth disease (HFMD): emerging epidemiology and the need for a vaccine strategy.

PubMed

Aswathyraj, S; Arunkumar, G; Alidjinou, E K; Hober, D

2016-10-01

Hand, foot, and mouth disease (HFMD) is a contagious viral disease and mainly affects infants and young children. The main manifestations are fever, vesicular rashes on hand, feet and buttocks and ulcers in the oral mucosa. Usually, HFMD is self-limiting, but a small proportion of children may experience severe complications such as meningitis, encephalitis, acute flaccid paralysis and neurorespiratory syndrome. Historically, outbreaks of HFMD were mainly caused by two enteroviruses: the coxsackievirus A16 (CV-A16) and the enterovirus 71 (EV-A71). In the recent years, coxsackievirus A6 and coxsackievirus A10 have been widely associated with both sporadic cases and outbreaks of HFMD worldwide, particularly in India, South East Asia and Europe with an increased frequency of neurological complications as well as mortality. Currently, there is no pharmacological intervention or vaccine available for HFMD. A formalin-inactivated EV-A71 vaccine has completed clinical trial in several Asian countries. However, this vaccine cannot protect against other major emerging etiologies of HFMD such as CV-A16, CV-A6 and CV-A10. Therefore, the development of a globally representative multivalent HFMD vaccine could be the best strategy.

A cost-utility analysis of cervical cancer screening and human papillomavirus vaccination in the Philippines.

PubMed

Guerrero, Anna Melissa; Genuino, Anne Julienne; Santillan, Melanie; Praditsitthikorn, Naiyana; Chantarastapornchit, Varit; Teerawattananon, Yot; Alejandria, Marissa; Toral, Jean Anne

2015-07-30

Cervical cancer is the second leading cause of cancer cases and deaths among Filipino women because of inadequate access to screening and treatment services. This study aims to evaluate the health and economic benefits of HPV vaccination and its combination with different screening strategies to find the most optimal preventive strategy in the Philippines. A cost-utility analysis was conducted using an existing semi-Markov model to evaluate different screening (i.e., Pap smear, visual inspection with acetic acid) and vaccination strategies against HPV infection implemented alone or as part of a combination strategy at different coverage scenarios. The model was run using country-specific epidemiologic, cost and clinical parameters from a health system perspective. Sensitivity analysis was performed for vaccine efficacy, duration of protection and costs of vaccination, screening and treatment. Across all coverage scenarios, VIA has been shown to be a dominant and cost-saving screening strategy with incremental cost-effectiveness ratio (ICER) ranging from dominant to Php 61,059 (1443 USD) per QALY gained. VIA can reduce cervical cancer cases and deaths by 25%. Pap smear screening was found to be not cost-effective due to its high cost in the Philippines. Adding HPV vaccination at a cost of 54 USD per vaccinated girl on top of VIA screening was found to be potentially cost-effective using a threshold of 1 GDP per capita (i.e., Php 120,000 or 2835 USD/ QALY) with the most favorable assumption of providing lifelong immunity against high-risk oncogenic HPV types 16/18. The highest incremental QALY gain was achieved with 80% coverage of the combined strategy of VIA at 35 to 45 years old done every five years following vaccination at 11 years of age with an ICER of Php 33,126 (783 USD). This strategy may result in a two-thirds reduction in cervical cancer burden. HPV vaccination is not cost-effective when vaccine protection lasts for less than 20 years. High VIA coverage

The vaccines consistency approach project: an EPAA initiative.

PubMed

De Mattia, F; Hendriksen, C; Buchheit, K H; Chapsal, J M; Halder, M; Lambrigts, D; Redhead, K; Rommel, E; Scharton-Kersten, T; Sesardic, T; Viviani, L; Ragan, I

2015-01-01

The consistency approach for release testing of established vaccines promotes the use of in vitro, analytical, non-animal based systems allowing the monitoring of quality parameters during the whole production process. By using highly sensitive non-animal methods, the consistency approach has the potential to improve the quality of testing and to foster the 3Rs (replacement, refinement and reduction of animal use) for quality control of established vaccines. This concept offers an alternative to the current quality control strategy which often requires large numbers of laboratory animals. In order to facilitate the introduction of the consistency approach for established human and veterinary vaccine quality control, the European Partnership for Alternatives to Animal Testing (EPAA) initiated a project, the "Vaccines Consistency Approach Project", aiming at developing and validating the consistency approach with stakeholders from academia, regulators, OMCLs, EDQM, European Commission and industry. This report summarises progress since the project's inception.

Glucosylceramide Administration as a Vaccination Strategy in Mouse Models of Cryptococcosis

PubMed Central

Mor, Visesato; Farnoud, Amir M.; Singh, Ashutosh; Rella, Antonella; Tanno, Hiromasa; Ishii, Keiko; Kawakami, Kazuyoshi; Sato, Toshiya; Del Poeta, Maurizio

2016-01-01

Cryptococcus neoformans is an opportunistic fungal pathogen and the causative agent of the disease cryptococcosis. Cryptococcosis is initiated as a pulmonary infection and in conditions of immune deficiency disseminates to the blood stream and central nervous system, resulting in life-threatening meningoencephalitis. A number of studies have focused on the development of a vaccine against Cryptococcus, primarily utilizing protein-conjugated components of the Cryptococcus polysaccharide capsule as antigen. However, there is currently no vaccine against Cryptococcus in the clinic. Previous studies have shown that the glycosphingolipid, glucosylceramide (GlcCer), is a virulence factor in C. neoformans and antibodies against this lipid inhibit fungal growth and cell division. In the present study, we have investigated the possibility of using GlcCer as a therapeutic agent against C. neoformans infections in mouse models of cryptococcosis. GlcCer purified from a non-pathogenic fungus, Candida utilis, was administered intraperitoneally, prior to infecting mice with a lethal dose of C. neoformans. GlcCer administration prevented the dissemination of C. neoformans from the lungs to the brain and led to 60% mouse survival. GlcCer administration did not cause hepatic injury and elicited an anti-GlcCer antibody response, which was observed independent of the route of administration and the strains of mouse. Taken together, our results suggest that fungal GlcCer can protect mice against lethal doses of C. neoformans infection and can provide a viable vaccination strategy against Cryptococcus. PMID:27082428

Glucosylceramide Administration as a Vaccination Strategy in Mouse Models of Cryptococcosis.

PubMed

Mor, Visesato; Farnoud, Amir M; Singh, Ashutosh; Rella, Antonella; Tanno, Hiromasa; Ishii, Keiko; Kawakami, Kazuyoshi; Sato, Toshiya; Del Poeta, Maurizio

2016-01-01

Cryptococcus neoformans is an opportunistic fungal pathogen and the causative agent of the disease cryptococcosis. Cryptococcosis is initiated as a pulmonary infection and in conditions of immune deficiency disseminates to the blood stream and central nervous system, resulting in life-threatening meningoencephalitis. A number of studies have focused on the development of a vaccine against Cryptococcus, primarily utilizing protein-conjugated components of the Cryptococcus polysaccharide capsule as antigen. However, there is currently no vaccine against Cryptococcus in the clinic. Previous studies have shown that the glycosphingolipid, glucosylceramide (GlcCer), is a virulence factor in C. neoformans and antibodies against this lipid inhibit fungal growth and cell division. In the present study, we have investigated the possibility of using GlcCer as a therapeutic agent against C. neoformans infections in mouse models of cryptococcosis. GlcCer purified from a non-pathogenic fungus, Candida utilis, was administered intraperitoneally, prior to infecting mice with a lethal dose of C. neoformans. GlcCer administration prevented the dissemination of C. neoformans from the lungs to the brain and led to 60% mouse survival. GlcCer administration did not cause hepatic injury and elicited an anti-GlcCer antibody response, which was observed independent of the route of administration and the strains of mouse. Taken together, our results suggest that fungal GlcCer can protect mice against lethal doses of C. neoformans infection and can provide a viable vaccination strategy against Cryptococcus.

Self-enforcing regional vaccination agreements

PubMed Central

Klepac, Petra; Grenfell, Bryan T.; Laxminarayan, Ramanan

2016-01-01

In a highly interconnected world, immunizing infections are a transboundary problem, and their control and elimination require international cooperation and coordination. In the absence of a global or regional body that can impose a universal vaccination strategy, each individual country sets its own strategy. Mobility of populations across borders can promote free-riding, because a country can benefit from the vaccination efforts of its neighbours, which can result in vaccination coverage lower than the global optimum. Here we explore whether voluntary coalitions that reward countries that join by cooperatively increasing vaccination coverage can solve this problem. We use dynamic epidemiological models embedded in a game-theoretic framework in order to identify conditions in which coalitions are self-enforcing and therefore stable, and thus successful at promoting a cooperative vaccination strategy. We find that countries can achieve significantly greater vaccination coverage at a lower cost by forming coalitions than when acting independently, provided a coalition has the tools to deter free-riding. Furthermore, when economically or epidemiologically asymmetric countries form coalitions, realized coverage is regionally more consistent than in the absence of coalitions. PMID:26790996

Mandatory vaccinations in European countries, undocumented information, false news and the impact on vaccination uptake: the position of the Italian pediatric society.

PubMed

Bozzola, Elena; Spina, Giulia; Russo, Rocco; Bozzola, Mauro; Corsello, Giovanni; Villani, Alberto

2018-06-14

High rates of vaccination coverage are important in preventing infectious diseases. Enforcing mandatory vaccinations is one of the strategies that some Countries adopted to protect the community when vaccination coverage is not satisfactory. In Italy, in 2017 vaccination against diphtheria, tetanus, pertussis, hepatitis B, poliovirus, Haemophilus influenzae type b, measles, mumps, rubella and varicella became compulsory in childhood. In order to contrast vaccination policies, anti-vaccination campaigns contribute to the spread of fake news. Among them, there is the false information that Italy is the only one country with mandatory vaccination policy. Aim of our study is confronting vaccination policies in children under 18 months against among different European countries for the following vaccines: diphtheria, tetanus, pertussis, hepatitis B, poliovirus, Haemophilus influenzae type b, measles, mumps, rubella and varicella. Information on policies of mandatory or recommended vaccinations of the European Countries were gathered by ECDC and compared to the Italian one. European Countries recommend or contemplate compulsory vaccines. Among them, eleven Countries (35.4%) have mandatory vaccinations for at least one out of diphtheria, tetanus, pertussis, hepatitis B, poliovirus, Haemophilus influenzae type b, measles, mumps, rubella and varicella vaccine. Not only in Italy, vaccination against diphtheria, tetanus, pertussis, hepatitis B, poliovirus, Haemophilus influenzae type b, measles, mumps, rubella and varicella is mandatory in children under 18 months. Other European countries adopted compulsory policies in order to prevent the spread of infectious diseases and to protect the community.

Assessing determinants of the intention to accept a pertussis cocooning vaccination: A survey among Dutch parents.

PubMed

Visser, Olga; Kraan, Janneke; Akkermans, Reinier; Ruiter, Robert A C; van der Velden, Koos; Hautvast, Jeannine L A; Hulscher, Marlies E J L

2016-09-07

Pertussis cocooning is one of the strategies aiming to prevent the potential harm of pertussis in infants by vaccinating (among others) their parents. Several countries adopted this strategy, but uptake is a problem. Determinants of parental uptake are important in the design of an effective vaccination programme. Therefore, this study aims to assess parents' intention to accept a pertussis cocooning vaccination and its determinants. A 98 item questionnaire was developed based on a theoretical framework, assessing parents' intention to accept a pertussis cocooning vaccination and its personal and psychosocial determinants. In addition, beliefs underlying parents' attitude towards pertussis cocooning vaccination were assessed. Both logistic and linear regression analysis were used to assess univariate and multivariate associations amongst study variables. Parents returned 282 questionnaires. The majority of the parents (78%) reported a positive intention to accept a pertussis cocooning vaccination. Attitude (OR 6.6, p<.001), anticipated negative affect in response to non acceptance (OR 1.65, p<.001), anticipated negative affect in response to acceptance (OR 0.55, p .040) and decisional uncertainty (OR 0.52, p .002) were significantly associated with intention. General vaccination beliefs (β 0.58, p<.001), moral norm (β 0.22, p<.001), perceived susceptibility of pertussis in children (β 0.10, p.004), and efficacy outcome expectations (β 0.15, p.011) were significant correlates of attitude towards pertussis cocooning vaccination. The parental intention to accept a pertussis cocooning vaccination in this study is rather high. Targeting the identified determinants of parents' acceptance in a pertussis cocooning vaccination programme is crucial to secure that intention is translated into actual vaccination uptake. Copyright © 2016 Elsevier Ltd. All rights reserved.

Knowledge, attitude, and uptake related to human papillomavirus vaccination among young women in Germany recruited via a social media site

PubMed Central

Remschmidt, Cornelius; Walter, Dietmar; Schmich, Patrick; Wetzstein, Matthias; Deleré, Yvonne; Wichmann, Ole

2014-01-01

Background: Many industrialized countries have introduced human papillomavirus (HPV) vaccination of young women, but vaccine uptake often remains suboptimal. This study aimed to investigate whether a social media site like Facebook is an appropriate tool to assess knowledge, attitude and uptake related to HPV vaccination in young women in Germany. Methods: Between December 2012 and January 2013 two different targeting strategies were implemented on Facebook, providing a link to an online questionnaire. Advertisements were displayed to female Facebook users aged 18–25 years living in Germany. During the simple targeting strategy, advertisements comprised health-related images along with various short titles and text messages. During the focused strategy, advertisements were targeted to users who in addition had certain fashion brands or pop stars listed on their profiles. The targeting strategies were compared with respect to participant characteristics. Univariate and multivariate analyses were used to identify factors associated with HPV vaccine uptake. Results: A total of 1161 women participated. The two targeting strategies resulted in significant differences regarding educational status and migrant background. Overall, awareness of HPV was high, but only 53% received at least one vaccine dose. In multivariate analysis, HPV vaccine uptake was independently associated with a physician's recommendation and trust in vaccine effectiveness. Concerns of adverse effects were negatively associated with vaccine uptake. Discussion: Social network recruitment permits fast and convenient access to young people. Sample characteristics can be manipulated by adjusting targeting strategies. There is further need for promoting knowledge of HPV vaccination among young women. Physicians have a major role in the vaccination decision-making process of young women. PMID:25483492

Live attenuated pre-erythrocytic malaria vaccines.

PubMed

Keitany, Gladys J; Vignali, Marissa; Wang, Ruobing

2014-01-01

Although recent control measures have significantly reduced malaria cases and deaths in many endemic areas, an effective vaccine will be essential to eradicate this parasitic disease. Malaria vaccine strategies developed to date focus on different phases of the parasite's complex life cycle in the human host and mosquito vector, and include both subunit-based and whole-parasite vaccines. This review focuses on the 3 live-attenuated malaria vaccination strategies that have been tested in humans to date, and discusses their progress, challenges and the immune correlates of protection that have been identified.

Human Papilloma Virus associated with oral cancer and preventive strategies: the role of vaccines.

PubMed

Ottria, L; Candotto, V; Cura, F; Baggi, L; Arcuri, C; Nardone, M; Gaudio, R M; Gatto, R; Spadari, F; Carinci, F

2018-01-01

The aim of this paper is to describe the efficacy of Human Papilloma Virus (HPV) vaccines for preventing oral cancer. A systematic review of the literature was conducted to describe the state of the art about HPV vaccines for preventing oral cancer. The aspects of prevention and control of infection by administering vaccines and the diffusion of sexual education campaigns are discussed also. In recent years there has been a growing interest in HPV in dentistry, suggesting a role of such a family of viruses in the development of oral cancers as well as of the uterine cervix. Even if the mass media have increasingly faced the problem, causing frequent alarming among patients, the dentist therefore needs a complete and up-to-date knowledge of this infectious condition that is one of the most common causes of sexually transmitted mucous membrane infections (eg genital, anal and oral). Recent studies about HPV infection are a basic requirement in order to promote the HPV vaccinations and patient’s health.

Finding optimal vaccination strategies for pandemic influenza using genetic algorithms.

PubMed

Patel, Rajan; Longini, Ira M; Halloran, M Elizabeth

2005-05-21

In the event of pandemic influenza, only limited supplies of vaccine may be available. We use stochastic epidemic simulations, genetic algorithms (GA), and random mutation hill climbing (RMHC) to find optimal vaccine distributions to minimize the number of illnesses or deaths in the population, given limited quantities of vaccine. Due to the non-linearity, complexity and stochasticity of the epidemic process, it is not possible to solve for optimal vaccine distributions mathematically. However, we use GA and RMHC to find near optimal vaccine distributions. We model an influenza pandemic that has age-specific illness attack rates similar to the Asian pandemic in 1957-1958 caused by influenza A(H2N2), as well as a distribution similar to the Hong Kong pandemic in 1968-1969 caused by influenza A(H3N2). We find the optimal vaccine distributions given that the number of doses is limited over the range of 10-90% of the population. While GA and RMHC work well in finding optimal vaccine distributions, GA is significantly more efficient than RMHC. We show that the optimal vaccine distribution found by GA and RMHC is up to 84% more effective than random mass vaccination in the mid range of vaccine availability. GA is generalizable to the optimization of stochastic model parameters for other infectious diseases and population structures.

The biography of the immune system and the control of cancer: from St Peregrine to contemporary vaccination strategies.

PubMed

Krone, Bernd; Kölmel, Klaus F; Grange, John M

2014-08-16

The historical basis and contemporary evidence for the use of immune strategies for prevention of malignancies are reviewed. Emphasis is focussed on the Febrile Infections and Melanoma (FEBIM) study on melanoma and on malignancies that seem to be related to an overexpression of human endogenous retrovirus K (HERV-K). It is claimed that, as a result of recent observational studies, measures for prevention of some malignancies such as melanoma and certain forms of leukaemia are already at hand: vaccination with Bacille Calmette-Guérin (BCG) of new-borns and vaccination with the yellow fever 17D (YFV) vaccine of adults. While the evidence of their benefit for prevention of malignancies requires substantiation, the observations that vaccinations with BCG and/or vaccinia early in life improved the outcome of patients after surgical therapy of melanoma are of practical relevance as the survival advantage conferred by prior vaccination is greater than any contemporary adjuvant therapy. The reviewed findings open a debate as to whether controlled vaccination studies should be conducted in patients and/or regions for whom/where they are needed most urgently. A study proposal is made and discussed. If protection is confirmed, the development of novel recombinant vaccines with wider ranges of protection based, most likely, on BCG, YFV or vaccinia, could be attempted.

Vaccination Against Tuberculosis With Whole-Cell Mycobacterial Vaccines.

PubMed

Scriba, Thomas J; Kaufmann, Stefan H E; Henri Lambert, Paul; Sanicas, Melvin; Martin, Carlos; Neyrolles, Olivier

2016-09-01

Live attenuated and killed whole-cell vaccines (WCVs) offer promising vaccination strategies against tuberculosis. A number of WCV candidates, based on recombinant bacillus Calmette-Guerin (BCG), attenuated Mycobacterium tuberculosis, or related mycobacterial species are in various stages of preclinical or clinical development. In this review, we discuss the vaccine candidates and key factors shaping the development pathway for live and killed WCVs and provide an update on progress. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Evaluating Vaccination Strategies for Zika Virus in the Americas.

PubMed

Durham, David P; Fitzpatrick, Meagan C; Ndeffo-Mbah, Martial L; Parpia, Alyssa S; Michael, Nelson L; Galvani, Alison P

2018-05-01

Mosquito-borne and sexually transmitted Zika virus has become widespread across Central and South America and the Caribbean. Many Zika vaccine candidates are under active development. To quantify the effect of Zika vaccine prioritization of females aged 9 to 49 years, followed by males aged 9 to 49 years, on incidence of prenatal Zika infections. A compartmental model of Zika transmission between mosquitoes and humans was developed and calibrated to empirical estimates of country-specific mosquito density. Mosquitoes were stratified into susceptible, exposed, and infected groups; humans were stratified into susceptible, exposed, infected, recovered, and vaccinated groups. Age-specific fertility rates, Zika sexual transmission, and country-specific demographics were incorporated. 34 countries and territories in the Americas with documented Zika outbreaks. Males and females aged 9 to 49 years. Age- and sex-targeted immunization using a Zika vaccine with 75% efficacy. Annual prenatal Zika infections. For a base-case vaccine efficacy of 75% and vaccination coverage of 90%, immunizing females aged 9 to 49 years (the World Health Organization target population) would reduce the incidence of prenatal infections by at least 94%, depending on the country-specific Zika attack rate. In regions where an outbreak is not expected for at least 10 years, vaccination of women aged 15 to 29 years is more efficient than that of women aged 30 years or older. Population-level modeling may not capture all local and neighborhood-level heterogeneity in mosquito abundance or Zika incidence. A Zika vaccine of moderate to high efficacy may virtually eliminate prenatal infections through a combination of direct protection and transmission reduction. Efficiency of age-specific targeting of Zika vaccination depends on the timing of future outbreaks. National Institutes of Health.

Intranasal cold-adapted influenza virus vaccine combined with inactivated influenza virus vaccines: an extra boost for the elderly?

PubMed

Targonski, Paul V; Poland, Gregory A

2004-01-01

Although influenza vaccine delivery strategies have improved coverage rates to unprecedented levels nationally among persons aged 65 years and older, influenza remains one of the greatest vaccine-preventable threats to public health among elderly in the US. A new, intranasal live attenuated influenza vaccine (LAIV) was recently approved by the US FDA for use in persons aged 5-49 years, which excludes the elderly population. Limitations of immune response to inactivated influenza vaccine (IAIV) and effectiveness of current influenza vaccination strategies among the elderly suggest that a combined approach using LAIV and/or the IAIV in various permutations might benefit this group. We explore characteristics of the LAIV, data regarding its utility in protecting against influenza in the elderly, and challenges and opportunities regarding potential combined inactivated/live attenuated vaccination strategies for the elderly. Although LAIV appears to hold promise either alone or in combination with IAIV, large well conducted randomised trials are necessary to define further the role of LAIV in preventing influenza morbidity and mortality among the elderly. We also suggest that innovative vaccine coverage strategies designed to optimise prevention and control of influenza and minimise viral transmission in the community must accompany, in parallel, the acquisition of clinical trials data to best combat morbidity and mortality from influenza.

Manipulating Google’s Knowledge Graph Box to Counter Biased Information Processing During an Online Search on Vaccination: Application of a Technological Debiasing Strategy

PubMed Central

Allam, Ahmed; Schulz, Peter J

2016-01-01

Background One of people’s major motives for going online is the search for health-related information. Most consumers start their search with a general search engine but are unaware of the fact that its sorting and ranking criteria do not mirror information quality. This misconception can lead to distorted search outcomes, especially when the information processing is characterized by heuristic principles and resulting cognitive biases instead of a systematic elaboration. As vaccination opponents are vocal on the Web, the chance of encountering their non‒evidence-based views on immunization is high. Therefore, biased information processing in this context can cause subsequent impaired judgment and decision making. A technological debiasing strategy could counter this by changing people’s search environment. Objective This study aims at testing a technological debiasing strategy to reduce the negative effects of biased information processing when using a general search engine on people’s vaccination-related knowledge and attitudes. This strategy is to manipulate the content of Google’s knowledge graph box, which is integrated in the search interface and provides basic information about the search topic. Methods A full 3x2 factorial, posttest-only design was employed with availability of basic factual information (comprehensible vs hardly comprehensible vs not present) as the first factor and a warning message as the second factor of experimental manipulation. Outcome variables were the evaluation of the knowledge graph box, vaccination-related knowledge, as well as beliefs and attitudes toward vaccination, as represented by three latent variables emerged from an exploratory factor analysis. Results Two-way analysis of variance revealed a significant main effect of availability of basic information in the knowledge graph box on participants’ vaccination knowledge scores (F2,273=4.86, P=.01), skepticism/fear of vaccination side effects (F2,273=3.5, P=.03

Therapeutic vaccines for leishmaniasis.

PubMed

Khamesipour, Ali

2014-11-01

Numerous therapeutic strategies are used to treat leishmaniasis. The treatment of cutaneous leishmaniasis (CL) is solely depends on antimonate derivatives with safety issues and questionable efficacy and there is no fully effective modality to treat CL caused by Leishmania tropica and Leishmania braziliensis. There is no prophylactic vaccine available against any form of leishmaniasis. Immunotherapy for CL has a long history; immunotherapy trials of first and second generation vaccines showed promising results. The current article briefly covers the prophylactic vaccines and explains different immunotherapy strategies that have been used to treat leishmaniasis. This paper does not include experimental vaccines and only lays emphasis on human trials and those vaccines which reached human trials. Immunotherapy is currently used to successfully treat several disorders; Low cost, limited side effects and no possibility to develop resistance make immunotherapy a valuable choice especially for infectious disease with chemotherapy problems. Efforts are needed to explore the immunological surrogate marker(s) of cure and protection in leishmaniasis and overcome the difficulties in standardization of crude Leishmania vaccines. One of the reasons for anti-leishmaniasis vaccine failure is lack of an appropriate adjuvant. So far, not enough attention has been paid to develop vaccines for immunotherapy of leishmaniasis.

Economic evaluation of Varicella vaccination: results of a systematic review

PubMed Central

Unim, Brigid; Saulle, Rosella; Boccalini, Sara; Taddei, Cristina; Ceccherini, Vega; Boccia, Antonio; Bonanni, Paolo; La Torre, Giuseppe

2013-01-01

Introduction: The aim of the present study is to review the economic burden of varicella disease and the benefit of universal varicella vaccination in different settings pending its implementation in all Italian regions. Materials and Methods: Research was conducted using PubMed, Scopus and ISI databases. Score quality and data extraction were performed for all included studies. Results: Twenty-three articles met the criteria: 15 cost-effectiveness, 8 cost-benefit and one cost-utility analysis. Varicella vaccination could save the society from €637,762 (infant strategy) to 53 million annually (combined infant and adolescent strategy). The median and the mean quality scores resulted in 91.8% and 85.4% respectively; 11 studies were considered of high quality and 12 of low quality. Discussion: The studies are favorable to the introduction of universal varicella vaccination in Italy, being cost saving and having a positive impact on morbidity. The quality score of the studies varied greatly: recent analyses were of comparable quality to older studies. PMID:23823940

Benefits and Effectiveness of Administering Pneumococcal Polysaccharide Vaccine With Seasonal Influenza Vaccine: An Approach for Policymakers

PubMed Central

Nanni, Angeline; Levine, Orin

2012-01-01

For the influenza pandemic of 2009–2010, countries responded to the direct threat of influenza but may have missed opportunities and strategies to limit secondary pneumococcal infections. Delivering both vaccines together can potentially increase pneumococcal polysaccharide vaccine (PPV23) immunization rates and prevent additional hospitalizations and mortality in the elderly and other high-risk groups. We used PubMed to review the literature on the concomitant use of PPV23 with seasonal influenza vaccines. Eight of 9 clinical studies found that a concomitant program conferred clinical benefits. The 2 studies that compared the cost-effectiveness of different strategies found concomitant immunization to be more cost-effective than either vaccine given alone. Policymakers should consider a stepwise strategy to reduce the burden of secondary pneumococcal infections during seasonal and pandemic influenza outbreaks. PMID:22397339

DNA vaccination for prostate cancer, from preclinical to clinical trials - where we stand?

PubMed Central

2012-01-01

Development of various vaccines for prostate cancer (PCa) is becoming an active research area. PCa vaccines are perceived to have less toxicity compared with the available cytotoxic agents. While various immune-based strategies can elicit anti-tumour responses, DNA vaccines present increased efficacy, inducing both humoural and cellular immunity. This immune activation has been proven effective in animal models and initial clinical trials are encouraging. However, to validate the role of DNA vaccination in currently available PCa management paradigms, strong clinical evidence is still lacking. This article provides an overview of the basic principles of DNA vaccines and aims to provide a summary of preclinical and clinical trials outlining the benefits of this immunotherapy in the management of PCa. PMID:23046944

Technical Transformation of Biodefense Vaccines

PubMed Central

Lu, Shan; Wang, Shixia

2013-01-01

Biodefense vaccines are developed against a diverse group of pathogens. Vaccines were developed for some of these pathogens a long time ago but they are facing new challenges to move beyond the old manufacturing technologies. New vaccines to be developed against other pathogens have to determine whether to follow traditional vaccination strategies or to seek new approaches. Advances in basic immunology and recombinant DNA technology have fundamentally transformed the process of formulating a vaccine concept, optimizing protective antigens, and selecting the most effective vaccine delivery approach for candidate biodefense vaccines. PMID:19837293

Motivational and contextual determinants of HPV-vaccination uptake: A longitudinal study among mothers of girls invited for the HPV-vaccination.

PubMed

Pot, Mirjam; van Keulen, Hilde M; Ruiter, Robert A C; Eekhout, Iris; Mollema, Liesbeth; Paulussen, Theo W G M

2017-07-01

In the Netherlands, HPV-vaccination uptake among 12-year-old girls remains to be lower (61% in 2016) than expected. The present study is about 1) replicating the extent to which social-psychological determinants found in earlier cross-sectional studies explain HPV-vaccination intention, and 2) testing whether HPV-vaccination intention, as well as other social-psychological determinants, are good predictors of future HPV-vaccination uptake in a longitudinal design. A random sample of mothers of girls invited for the vaccination in 2015 was drawn from the Dutch vaccination register (Praeventis) (N=36,000) and from three online panels (N=2483). Two months prior to the vaccination of girls, their mothers were requested to complete a web-based questionnaire by letter (Praeventis sample) or by e-mail (panel samples). HPV-vaccination uptake was derived from Praeventis. Backward linear and logistic regression analyses were conducted to examine most dominant predictors of HPV-vaccination intention and uptake, respectively. The total sample used for data analyses consisted of 8062 mothers. Response rates were 18% for the Praeventis sample and 47% for the panel samples. HPV-vaccination intention was best explained by attitude, beliefs, subjective norms, habit, and perceived relative effectiveness of the vaccination; they explained 83% of the variance in HPV-vaccination intention. Intention appeared to be the only stable predictor of HPV-vaccination uptake and explained 43% of the variance in HPV-vaccination uptake. These results confirm what was found by earlier cross-sectional studies, and provide strong leads for selecting relevant targets in the planning of future communication strategies aiming to improve HPV-vaccination uptake. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Cost-effectiveness analysis of the introduction of rotavirus vaccine in Iran.

PubMed

Javanbakht, Mehdi; Moradi-Lakeh, Maziar; Yaghoubi, Mohsen; Esteghamati, Abdoulreza; Mansour Ghanaie, Roxana; Mahmoudi, Sussan; Shamshiri, Ahmad-Reza; Zahraei, Seyed Mohsen; Baxter, Louise; Shakerian, Sareh; Chaudhri, Irtaza; Fleming, Jessica A; Munier, Aline; Baradaran, Hamid R

2015-05-07

Although the mortality from diarrheal diseases has been decreasing dramatically in Iran, it still represents an important proportion of disease burden in children <5 years old. Rotavirus vaccines are among the most effective strategies against diarrheal diseases in specific epidemiological conditions. This study aimed to evaluate the cost-effectiveness of the introduction of rotavirus vaccine (3 doses of pentavalent RotaTeq (RV5)) in Iran, from the viewpoints of Iran's health system and society. The TRIVAC decision support model was used to calculate total incremental costs, life years (LYs) gained, and disability-adjusted life years (DALYs) averted due to the vaccination program. Necessary input data were collected from the most valid accessible sources as well as a systematic review and meta-analysis on epidemiological studies. We used WHO guidelines to estimate vaccination cost. An annual discount rate of 3% was considered for both health gain and costs. A deterministic sensitivity analysis was performed for testing the robustness of the models results. Our results indicated that total DALYs potentially lost due to rotavirus diarrhea within 10 years would be 138,161, of which 76,591 could be prevented by rotavirus vaccine. The total vaccination cost for 10 cohorts was estimated to be US$ 499.91 million. Also, US$ 470.61 million would be saved because of preventing outpatient visits and inpatient admissions (cost-saving from the society perspective). We estimated a cost per DALY averted of US$ 2868 for RV5 vaccination, which corresponds to a highly cost-effective strategy from the government perspective. In the sensitivity analysis, all scenarios tested were still cost-saving or highly cost-effective from the society perspective, except in the least favorable scenario and low vaccine efficacy and disease incidence scenario. Based on the findings, introduction of rotavirus vaccine is a highly cost-effective strategy from the government perspective. Introducing the

Cost-effectiveness of conjugate meningococcal vaccination strategies in the United States.

PubMed

Shepard, Colin W; Ortega-Sanchez, Ismael R; Scott, R Douglas; Rosenstein, Nancy E

2005-05-01

The US Food and Drug Administration approved a meningococcal conjugate A/C/Y/W-135 vaccine (MCV-4) for use in persons aged 11 to 55 years in January, 2005; licensure for use in younger age groups is expected in 2 to 4 years. To evaluate and compare the projected health and economic impact of MCV-4 vaccination of US adolescents, toddlers, and infants. Cost-effectiveness analysis from a societal perspective based on data from Active Bacterial Core Surveillance (ABCs) and other published and unpublished sources. Sensitivity analyses in which key input measures were varied over plausible ranges were performed. A hypothetical 2003 US population cohort of children 11 years of age and a 2003 US birth cohort. Hypothetical routine vaccination of adolescents (1 dose at 11 years of age), toddlers (1 dose at 1 year of age), and infants (3 doses at 2, 4, and 6 months of age). Each vaccination scenario was compared with a "no-vaccination" scenario. Meningococcal cases and deaths prevented, cost per case prevented, cost per life-year saved, and cost per quality-adjusted life-year saved. Routine MCV-4 vaccination of US adolescents (11 years of age) would prevent 270 meningococcal cases and 36 deaths in the vaccinated cohort over 22 years, a decrease of 46% in the expected burden of disease. Before program costs are counted, adolescent vaccination would reduce direct disease costs by $18 million and decrease productivity losses by $50 million. At a cost per vaccination (average public-private price per dose plus administration fees) of $82.50, adolescent vaccination would cost society $633000 per meningococcal case prevented and $121000 per life-year saved. Key variables influencing results were disease incidence, case-fatality ratio, and cost per vaccination. The cost-effectiveness of toddler vaccination is essentially equivalent to adolescent vaccination, whereas infant vaccination would be much less cost-effective. Routine MCV-4 vaccination of US children would reduce the burden

Vaccine Adjuvant Incorporation Strategy Dictates Peptide Amphiphile Micelle Immunostimulatory Capacity.

PubMed

Zhang, Rui; Kramer, Jake S; Smith, Josiah D; Allen, Brittany N; Leeper, Caitlin N; Li, Xiaolei; Morton, Logan D; Gallazzi, Fabio; Ulery, Bret D

2018-06-01

Current vaccine research has shifted from traditional vaccines (i.e., whole-killed or live-attenuated) to subunit vaccines (i.e., protein, peptide, or DNA) as the latter is much safer due to delivering only the bioactive components necessary to produce a desirable immune response. Unfortunately, subunit vaccines are very weak immunogens requiring delivery vehicles and the addition of immunostimulatory molecules termed adjuvants to convey protective immunity. An interesting type of delivery vehicle is peptide amphiphile micelles (PAMs), unique biomaterials where the vaccine is part of the nanomaterial itself. Due to the modularity of PAMs, they can be readily modified to deliver both vaccine antigens and adjuvants within a singular construct. Through the co-delivery of a model antigenic epitope (Ovalbumin 319-340 -OVA BT ) and a known molecular adjuvant (e.g., 2,3-dipalmitoyl-S-glyceryl cysteine-Pam 2 C), greater insight into the mechanisms by which PAMs can exert immunostimulatory effects was gained. It was found that specific combinations of antigen and adjuvant can significantly alter vaccine immunogenicity both in vitro and in vivo. These results inform fundamental design rules that can be leveraged to fabricate optimal PAM-based vaccine formulations for future disease-specific applications. Graphical Abstract.

Flu vaccination communication in Europe: What does the government communicate and how?

PubMed

Ohlrogge, Anne Wiebke; Suggs, L Suzanne

2018-04-24

The Flu vaccine is the most effective measure to prevent influenza. Yet, vaccination rates remain at sub-optimal levels, with 10%-29% coverage rates in the general population of the EU. As mistrust in vaccines has increased, effective strategies are needed and one is communication. The aim of this research is to identify vaccination recommendations of the health ministries in 5 European Member States and to investigate the communication strategies used. Two methods were employed in this study. A review of flu vaccination recommendations in the European Union and five Members States (Austria, Germany, Malta, Ireland and United Kingdom). Next a content analysis was conducted of flu vaccination communication in those six contexts. All countries recommend flu vaccination as a primary protection tool, but they differed in their recommendations for various target audiences. Channels for communication included seven websites and 42 other materials. The main messages used were gained framed promoting protection, either for oneself, family or patients. Most communications provided basic information replying on providing facts and knowledge about the flu and the benefits of vaccination. No information on the development of the communication or its effects were found. Communicating flu vaccination as a protective tool is common across countries and is consistent with the benefits of vaccination. Furthermore, the communications in the countries were not consistent with their recommendations. As the recommendations vary across and within countries, communication becomes a challenge. They should, at a minimum, be consistent with EU and country specific recommendations. Copyright © 2018 Elsevier Ltd. All rights reserved.

Whole organism blood stage vaccines against malaria.

PubMed

Stanisic, Danielle I; Good, Michael F

2015-12-22

Despite a century of research focused on the development and implementation of effective control strategies, infection with the malaria parasite continues to result in significant morbidity and mortality worldwide. An effective malaria vaccine is considered by many to be the definitive solution. Yet, after decades of research, we are still without a vaccine that is capable of inducing robust, long lasting protection in naturally exposed individuals. Extensive sub-unit vaccine development focused on the blood stage of the malaria parasite has thus far yielded disappointing results. There is now a renewed focus on whole parasite vaccine strategies, particularly as they may overcome some of the inherent weaknesses deemed to be associated with the sub-unit approach. This review discusses the whole parasite vaccine strategy focusing on the blood stage of the malaria parasite, with an emphasis on recent advances and challenges in the development of killed and live attenuated vaccines. Copyright © 2015 Elsevier Ltd. All rights reserved.

Severe post-vaccination reaction to 17D yellow fever vaccine in Nigeria.

PubMed

Oyelami, S A; Olaleye, O D; Oyejide, C O; Omilabu, S A; Fatunla, B A

1994-01-01

An unusual outbreak of post-vaccination reactions to 17D yellow fever vaccine occurred at Shaki, Nigeria, in May 1987. Twenty-five of the affected people were treated at the Baptist Hospital Shaki. The patients presented with rapidly progressing swelling of the left arm with associated fever and other constitutional symptoms few hours after inoculation with the vaccine. Some of the patients developed gangrene of the affected limb, five of them went into coma and died. Poor hygiene and improper handling of vaccine as well as contamination of vaccine from the source are possible causes. A review of vaccine delivery strategies especially at local community levels; sound training, supervision of vaccinators and health education are strongly recommended to prevent reoccurrence of similar reactions.

Vaccine Hesitancy.

PubMed

Jacobson, Robert M; St Sauver, Jennifer L; Finney Rutten, Lila J

2015-11-01

Vaccine refusal received a lot of press with the 2015 Disneyland measles outbreak, but vaccine refusal is only a fraction of a much larger problem of vaccine delay and hesitancy. Opposition to vaccination dates back to the 1800 s, Edward Jenner, and the first vaccine ever. It has never gone away despite the public's growing scientific sophistication. A variety of factors contribute to modern vaccine hesitancy, including the layperson's heuristic thinking when it comes to balancing risks and benefits as well as a number of other features of vaccination, including falling victim to its own success. Vaccine hesitancy is pervasive, affecting a quarter to a third of US parents. Clinicians report that they routinely receive requests to delay vaccines and that they routinely acquiesce. Vaccine rates vary by state and locale and by specific vaccine, and vaccine hesitancy results in personal risk and in the failure to achieve or sustain herd immunity to protect others who have contraindications to the vaccine or fail to generate immunity to the vaccine. Clinicians should adopt a variety of practices to combat vaccine hesitancy, including a variety of population health management approaches that go beyond the usual call to educate patients, clinicians, and the public. Strategies include using every visit to vaccinate, the creation of standing orders or nursing protocols to provide vaccination without clinical encounters, and adopting the practice of stating clear recommendations. Up-to-date, trusted resources exist to support clinicians' efforts in adopting these approaches to reduce vaccine hesitancy and its impact. Copyright © 2015 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Vaccinating healthcare workers: Level of implementation, barriers and proposal for evidence-based policies in Turkey

PubMed Central

Tanriover, Mine Durusu; Altınel, Serdar; Unal, Serhat

2017-01-01

ABSTRACT The role of healthcare workers in life-long vaccination is very important in the means of 2 sided infection, rising patient awareness and being a role model for the patients. Numerous organizations publish guidelines for vaccination of HCWs, while healthcare facilities develop vaccination policies according to the accreditation standards. Nevertheless, vaccination rates among HCWs are far below targets. The obstacles to getting vaccinated or recommending vaccination may include rather universal factors such as the vaccine paradox, however in the case of HCWs, probably a different set of factors are included. The aims of this article are to gain an overview of vaccination strategies for HCWs, to assess the coverage rates of HCWs and make in-depth analyses of the potential barriers to vaccination and potential factors to motivate HCWs for vaccination in Turkey and to compare them with the global picture to improve implementation of policies concerning vaccination of HCWs. PMID:28059668

Vaccines and Immunization Practice.

PubMed

Hogue, Michael D; Meador, Anna E

2016-03-01

Vaccines are among most cost-effective public health strategies. Despite effective vaccines for many bacterial and viral illnesses, tens of thousands of adults and hundreds of children die each year in the United States from vaccine-preventable diseases. Underutilization of vaccines requires rethinking the approach to incorporating vaccines into practice. Arguably, immunizations could be a part all health care encounters. Shared responsibility is paramount if deaths are to be reduced. This article reviews the available vaccines in the US market, as well as practice recommendations of the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices. Copyright © 2016 Elsevier Inc. All rights reserved.

Parasite Carbohydrate Vaccines.

PubMed

Jaurigue, Jonnel A; Seeberger, Peter H

2017-01-01

Vaccination is an efficient means of combating infectious disease burden globally. However, routine vaccines for the world's major human parasitic diseases do not yet exist. Vaccines based on carbohydrate antigens are a viable option for parasite vaccine development, given the proven success of carbohydrate vaccines to combat bacterial infections. We will review the key components of carbohydrate vaccines that have remained largely consistent since their inception, and the success of bacterial carbohydrate vaccines. We will then explore the latest developments for both traditional and non-traditional carbohydrate vaccine approaches for three of the world's major protozoan parasitic diseases-malaria, toxoplasmosis, and leishmaniasis. The traditional prophylactic carbohydrate vaccine strategy is being explored for malaria. However, given that parasite disease biology is complex and often arises from host immune responses to parasite antigens, carbohydrate vaccines against deleterious immune responses in host-parasite interactions are also being explored. In particular, the highly abundant glycosylphosphatidylinositol molecules specific for Plasmodium, Toxoplasma , and Leishmania spp. are considered exploitable antigens for this non-traditional vaccine approach. Discussion will revolve around the application of these protozoan carbohydrate antigens for vaccines currently in preclinical development.

Parasite Carbohydrate Vaccines

PubMed Central

Jaurigue, Jonnel A.; Seeberger, Peter H.

2017-01-01

Vaccination is an efficient means of combating infectious disease burden globally. However, routine vaccines for the world's major human parasitic diseases do not yet exist. Vaccines based on carbohydrate antigens are a viable option for parasite vaccine development, given the proven success of carbohydrate vaccines to combat bacterial infections. We will review the key components of carbohydrate vaccines that have remained largely consistent since their inception, and the success of bacterial carbohydrate vaccines. We will then explore the latest developments for both traditional and non-traditional carbohydrate vaccine approaches for three of the world's major protozoan parasitic diseases—malaria, toxoplasmosis, and leishmaniasis. The traditional prophylactic carbohydrate vaccine strategy is being explored for malaria. However, given that parasite disease biology is complex and often arises from host immune responses to parasite antigens, carbohydrate vaccines against deleterious immune responses in host-parasite interactions are also being explored. In particular, the highly abundant glycosylphosphatidylinositol molecules specific for Plasmodium, Toxoplasma, and Leishmania spp. are considered exploitable antigens for this non-traditional vaccine approach. Discussion will revolve around the application of these protozoan carbohydrate antigens for vaccines currently in preclinical development. PMID:28660174

[Vaccine application of recombinant herpesviruses].

PubMed

Yokoyama, N; Xuan, X; Mikami, T

2000-04-01

Recently, genetic engineering using recombinant DNA techniques has been applied to design new viral vaccines in order to reduce some problems which the present viral vaccines have. Up to now, many viruses have been investigated for development of recombinant attenuated vaccines or live viral vectors for delivery of foreign genes coding immunogenic antigens. In this article, we introduced the new vaccine strategy using genetically engineered herpesviruses.

Classical swine fever vaccines-State-of-the-art.

PubMed

Blome, Sandra; Moß, Claudia; Reimann, Ilona; König, Patricia; Beer, Martin

2017-07-01

Due to its impact on animal health and pig industry, classical swine fever (CSF) is still one of the most important viral diseases of pigs. To control the disease, safe and highly efficacious live attenuated vaccines exist for decades. These vaccines have usually outstanding efficacy and safety but lack differentiability of infected from vaccinated animals (DIVA or marker strategy). In contrast, the first generation of E2 subunit marker vaccines shows constraints in efficacy, application, and production. To overcome these limitations, new generations of marker vaccines are developed. A wide range of approaches have been tried including recombinant vaccines, recombinant inactivated vaccines or subunit vaccines, vector vaccines, and DNA/RNA vaccines. During the last years, especially attenuated deletion vaccines or chimeric constructs have shown potential. At present, especially two new constructs have been intensively tested, the adenovirus-delivered, Semliki Forest virus replicon-vectored marker vaccine candidate "rAdV-SFV-E2" and the pestivirus chimera "CP7_E2alf". The later was recently licensed by the European Medicines Agency. Under field conditions, all marker vaccines have to be accompanied by a potent test system. Particularly this point shows still weaknesses and it is important to embed vaccination in a well-established vaccination strategy and a suitable diagnostic workflow. In summary, conventional vaccines are a standard in terms of efficacy. However, only vaccines with DIVA will allow improved eradication strategies e.g. also under emergency vaccination conditions in free regions. To answer this demand, new generations of marker vaccines have been developed and add now to the tool box of CSF control. Copyright © 2017 Elsevier B.V. All rights reserved.

Emerging human papillomavirus vaccines

PubMed Central

Ma, Barbara; Maraj, Bharat; Tran, Nam Phuong; Knoff, Jayne; Chen, Alexander; Alvarez, Ronald D; Hung, Chien-Fu; Wu, T.-C.

2013-01-01

Introduction Identification of human papillomavirus (HPV) as the etiologic factor of cervical, anogenital, and a subset of head and neck cancers has stimulated the development of preventive and therapeutic HPV vaccines to control HPV-associated malignancies. Excitement has been generated by the commercialization of two preventive L1-based vaccines, which use HPV virus-like particles (VLPs) to generate capsid-specific neutralizing antibodies. However, factors such as high cost and requirement for cold chain have prevented widespread implementation where they are needed most. Areas covered Next generation preventive HPV vaccine candidates have focused on cost-effective stable alternatives and generating broader protection via targeting multivalent L1 VLPs, L2 capsid protein, and chimeric L1/L2 VLPs. Therapeutic HPV vaccine candidates have focused on enhancing T cell-mediated killing of HPV-transformed tumor cells, which constitutively express HPV-encoded proteins, E6 and E7. Several therapeutic HPV vaccines are in clinical trials. Expert opinion Although progress is being made, cost remains an issue inhibiting the use of preventive HPV vaccines in countries that carry the majority of the cervical cancer burden. In addition, progression of therapeutic HPV vaccines through clinical trials may require combination strategies employing different therapeutic modalities. As research in the development of HPV vaccines continues, we may generate effective strategies to control HPV-associated malignancies. PMID:23163511

Modelling the cost-effectiveness of a new infant vaccine to prevent tuberculosis disease in children in South Africa

PubMed Central

2014-01-01

Background Tuberculosis remains the leading cause of death in South Africa. A number of potential new TB vaccine candidates have been identified and are currently in clinical trials. One such candidate is MVA85A. This study aimed to estimate the cost-effectiveness of adding the MVA85A vaccine as a booster to the BCG vaccine in children from the perspective of the South African government. Methods The cost-effectiveness was assessed by employing Decision Analytic Modelling, through the use of a Markov model. The model compared the existing strategy of BCG vaccination to a new strategy in which infants receive BCG and a booster vaccine, MVA85A, at 4 months of age. The costs and outcomes of the two strategies are estimated through modelling the vaccination of a hypothetical cohort of newborns and following them from birth through to 10 years of age, employing 6-monthly cycles. Results The results of the cost-effectiveness analysis indicate that the MVA85A strategy is both more costly and more effective – there are fewer TB cases and deaths from TB than BCG alone. The South African government would need to spend an additional USD 1,105 for every additional TB case averted and USD 284,017 for every additional TB death averted. The threshold analysis shows that, if the efficacy of the MVA85A vaccine was 41.3% (instead of the current efficacy of 17.3%), the two strategies would have the same cost but more cases of TB and more deaths from TB would be prevented by adding the MVA85A vaccine to the BCG vaccine. In this case, the government chould consider the MVA85A strategy. Conclusions At the current level of efficacy, the MVA85A vaccine is neither effective nor cost-effective and, therefore, not a good use of limited resources. Nevertheless, this study contributes to developing a standardized Markov model, which could be used, in the future, to estimate the potential cost-effectiveness of new TB vaccines compared to the BCG vaccine, in children between the ages of 0�

[Vaccines: building on scientific excellence and dispelling false myths].

PubMed

Signorelli, Carlo

2015-01-01

The EU and Italian institutions have recently reiterated their commitment to harmonize and implement vaccination policies as a fundamental strategy for public health. Nonetheless, vaccines are losing public confidence. False myths related to vaccine adverse reactions and commercial interests, combined with the recent judgements of the Court and the "Fluad® episode", are fuelling vaccine hesitancy. In such a context, a lively debate is ongoing in Italian scientific community. Aim of this contribution is to recall the available solid scientific evidence demonstrating that vaccines are among the most effective prevention tools ever invented and recall the economic data that support the cost-effectiveness of the immunisation. As every other medicine, vaccines are registered after large and solid clinical trials have been conducted. Immunization schedules are proposed by experts in the field of clinical medicine, epidemiology and public health on the basis of the available scientific evidence, and then implemented by policy makers also taking into consideration resources allocation and financial sustainability. The false myth that vaccines are offered because of economic interests is to be dispelled;moreover, researchers, policy makers, scientific societies and the healthcare community at large should renew commitment to invest in health education and communication on vaccines, always disclosing potential conflicts of interests.

Mandatory and recommended vaccination in the EU, Iceland and Norway: results of the VENICE 2010 survey on the ways of implementing national vaccination programmes.

PubMed

Haverkate, M; D'Ancona, F; Giambi, C; Johansen, K; Lopalco, P L; Cozza, V; Appelgren, E

2012-05-31

This report provides an updated overview of recommended and mandatory vaccinations in the European Union (EU), Iceland and Norway, considering the differences in vaccine programme implementation between countries. In 2010, the Vaccine European New Integrated Collaboration Effort (VENICE) network, conducted a survey among the VENICE project gatekeepers to learn more about how national vaccination programmes are implemented, whether recommended or mandatory. Information was collected from all 27 EU Member States, Iceland and Norway. In total 15 countries do not have any mandatory vaccinations; the remaining 14 have at least one mandatory vaccination included in their programme. Vaccination against polio is mandatory for both children and adults in 12 countries; diphtheria and tetanus vaccination in 11 countries and hepatitis B vaccination in 10 countries. For eight of the 15 vaccines considered, some countries have a mixed strategy of recommended and mandatory vaccinations. Mandatory vaccination may be considered as a way of improving compliance to vaccination programmes. However, compliance with many programmes in Europe is high, using only recommendations. More information about the diversity in vaccine offer at European level may help countries to adapt vaccination strategies based on the experience of other countries. However, any proposal on vaccine strategies should be developed taking into consideration the local context habits.

Vaccine-derived polioviruses.

PubMed

Agol, Vadim I

2006-06-01

The Sabin oral poliovaccine (OPV) is extremely efficacious and safe, despite its inherent genetic instability. While reversion to nearly wild-type phenotype regularly occurs soon after the onset of OPV reproduction in the gastro-intestinal tract of vaccine recipients or their contacts, this is usually not a big problem, provided the vaccine is used either for mass vaccination or in populations with a relatively high level of anti-polio immunity. However, if these conditions are not met, the vaccine viruses are likely to be converted into highly transmissible agents with a nearly wild-type level of neurovirulence. Moreover, OPV viruses may persist and evolve even in adequately immunized populations. The current strategy for the "endgame" of poliovirus eradication envisions cessation of OPV usage shortly after the last isolation of a wild poliovirus. If implemented, this strategy would result in rapid growth of non-immune human populations at the time when OPV derivatives would very likely be persisting. Therefore, the planned cessation of OPV vaccination is associated with a very high, and in the author's opinion, unacceptable risk of polio outbreaks caused by OPV derivatives. The only currently available tool to curb such outbreaks is OPV, which should have been used at a global scale. Safe discontinuation of OPV vaccination will be possible only after an efficient new vaccine or an anti-poliovirus drug is available. To achieve this goal, stimulation of poliovirus research and elimination of organizational and financial obstacles preventing it are needed.

Comparing the health and social protection effects of measles vaccination strategies in Ethiopia: An extended cost-effectiveness analysis.

PubMed

Driessen, Julia; Olson, Zachary D; Jamison, Dean T; Verguet, Stéphane

2015-08-01

Vaccination coverage rates often mask wide variation in access, uptake, and cost of providing vaccination. Financial incentives have been effective at creating demand for social services in a variety of settings. Using methods of extended cost-effectiveness analysis, we compare the health and economic implications of three different vaccine delivery strategies for measles vaccination in Ethiopia: i) routine immunization, ii) routine immunization with financial incentives, and iii) mass campaigns, known as supplemental immunization activities (SIAs). We examine annual birth cohorts of almost 3,000,000 births over a ten year period, exploring variation in these outcomes based on economic status to understand how various options may improve equity. SIAs naturally achieve higher levels of vaccine coverage, but at higher costs. Routine immunization combined with financial incentives bolsters demand among more economically vulnerable households. The relative appeal of routine immunization with financial incentives and SIAs will depend on the policy environment, including short-term financial limitations, time horizons, and the types of outcomes that are desired. While the impact of financial incentives has been more thoroughly studied in other policy arenas, such as education, consideration of this approach alongside standard vaccination models such as SIAs is timely given the dialog around measles eradication. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

[Influenza, tetanus, and pertussis vaccination coverage among adults in Germany].

PubMed

Bödeker, Birte; Remschmidt, C; Müters, S; Wichmann, O

2015-02-01

In order to be adequately protected throughout life and to protect specific risk groups from particular diseases, regular booster or specific indicator vaccinations are also recommended during adulthood. Adults should be vaccinated against seasonal influenza (annually, e.g., persons with underlying chronic diseases and persons aged ≥ 60 years), tetanus (every 10 years), and pertussis (as a one-time vaccination with the next due tetanus vaccine and, e.g., when people have close contact to newborn babies). The aim of this study was to provide an overview of the current status of vaccination uptake among adults living in Germany, focusing on these three vaccines. In line with nationwide continuous health monitoring, the Robert Koch Institute conducted the representative study "German Health Update" (GEDA 2012) between 2012 and 2013. The survey is conducted regularly and adults are asked questions relating to their vaccination status through computer-assisted telephone interviews. Overall, 19,294 interviews were held. In 2010/2011 and 2011/2012, seasonal influenza uptake among persons aged ≥ 60 years was 54.3 and 52.6 % and among individuals with underlying chronic diseases 46.2 and 42.9 %. 7.6 and 75.6 % of participants reported up-to-date pertussis and tetanus vaccination, respectively. 22 % of people living with a baby in one household were vaccinated against pertussis. In general, vaccination rates against seasonal influenza, pertussis, and tetanus among adults are still low, but differ depending on the specific vaccination. The required aim of the European Commission to reach influenza vaccination coverage by the 2014/2015 winter season of 75 % of higher age groups has not yet been reached. The low pertussis vaccination coverage among persons in close household contact to infants poses a big challenge to the implementation of the cocooning strategy to protect the very vulnerable newborns. To emphasize the importance of a complete vaccination

Multiple Vaccinations: Friend or Foe

PubMed Central

Church, Sarah E.; Jensen, Shawn M.; Twitty, Chris; Bahjat, Keith; Hu, Hong-Ming; Urba, Walter J.; Fox, Bernard A.

2013-01-01

Few immunotherapists would accept the concept of a single vaccination inducing a therapeutic anti-cancer immune response in a patient with advanced cancer. But what is the evidence to support the “more-is-better” approach of multiple vaccinations? Since we are unaware of trials comparing the effect of a single vaccine versus multiple vaccinations on patient outcome, we considered that an anti-cancer immune response might provide a surrogate measure of the effectiveness of vaccination strategies. Since few large trials include immunological monitoring, the majority of information is gleaned from smaller trials in which an evaluation of immune responses to vaccine or tumor, before and at one or more times following the first vaccine was performed. In some studies there is convincing evidence that repeated administration of a specific vaccine can augment the immune response to antigens contained in the vaccine. In other settings multiple vaccinations can significantly reduce the immune response to one or more targets. Results from three large adjuvant vaccine studies support the potential detrimental effect of multiple vaccinations as clinical outcomes in the control arms were significantly better than that for treatment groups. Recent research has provided insights into mechanisms that are likely responsible for the reduced responses in the studies noted above, but supporting evidence from clinical specimens is generally lacking. Interpretation of these results is further complicated by the possibility that the dominant immune response may evolve to recognize epitopes not present in the vaccine. Nonetheless, the FDA-approval of the first therapeutic cancer vaccine and recent developments from preclinical models and clinical trials provide a substantial basis for optimism and a critical evaluation of cancer vaccine strategies. PMID:21952289

COST-EFFECTIVENESS ANALYSIS OF HERPES ZOSTER VACCINATION IN ITALIAN ELDERLY PERSONS.

PubMed

Coretti, Silvia; Codella, Paola; Romano, Federica; Ruggeri, Matteo; Cicchetti, Americo

2016-01-01

Herpes zoster (HZ) is characterized by a painful skin rash. Its main complication is postherpetic neuralgia (PHN), pain persisting or occurring after the rash onset. HZ treatment aims to reduce acute pain, impede the onset complications, and disease progression. The aim of this study was to assess the cost-effectiveness of HZ vaccination compared with no vaccination strategy, within the Italian context. The natural history of HZ and PHN was mapped through a Markov model with lifetime horizon. A population of patients aged between 60 and 79 years was hypothesized. Third party payer (Italian National Health Service, I-NHS) and societal perspectives were adopted. Data were derived from literature. The incremental cost-effectiveness ratio of the vaccination equaled EUR 11,943 per quality-adjusted life-year (QALY) under the I-NHS perspective and EUR 11,248 per QALY under the societal perspective. Considering a cost-effectiveness threshold of EUR 30,000/QALY, the multi-way sensitivity analysis showed that vaccination is cost-effective regardless of the perspective adopted, in 99 percent of simulations.

Evaluating a strategy to deliver vaccine to white-tailed deer at a landscape level

USGS Publications Warehouse

Fischer, Justin W.; Blass, Chad R.; Walter, W. David; Anderson, Charles W.; Lavelle, Michael J.; Hall, Wayne H.; VerCauterren, Kurt C.

2016-01-01

Effective delivery of vaccines and other pharmaceuticals to wildlife populations is needed when zoonotic diseases pose a risk to public health and natural resources or have considerable economic consequences. The objective of our study was to develop a bait-distribution strategy for potential delivery of oral bovine tuberculosis (bTB) vaccine to white-tailed deer (Odocoileus virginianus) where deer are reservoirs for the disease. During 17 February and 2 March 2011, we created a grid of experimental bait stations (n = 64) on Sandhill Wildlife Management Area, Wisconsin, USA, to assess station densities needed to attract and deliver placebo baits to free-ranging white-tailed deer and look for associations among deer density, number of bait stations per deer, and bait consumption. We placed 1 L of commercially available alfalfa cubes at bait stations 652 m apart, and monitored stations with motion-activated cameras for 5 days to document visitation and consumption by deer and nontarget species. Deer discovered 38% of all bait stations within 37 hr, on average (SE = 3.91 hr), and consumed variable amounts of bait at each station. Deer were documented in 94% of all photographs of wildlife at bait stations. We found no correlation between bait consumption and deer density or the number of bait stations per deer. We provide the first information on use of baits by free-ranging deer and nontarget wildlife to eventually vaccinate deer against bTB at a landscape level. The results of this study can further the development of strategies in delivery of pharmaceuticals to free-ranging white-tailed deer.

Applying Convergent Immunity to Innovative Vaccines Targeting Staphylococcus aureus

PubMed Central

Yeaman, Michael R.; Filler, Scott G.; Schmidt, Clint S.; Ibrahim, Ashraf S.; Edwards, John E.; Hennessey, John P.

2014-01-01

Recent perspectives forecast a new paradigm for future “third generation” vaccines based on commonalities found in diverse pathogens or convergent immune defenses to such pathogens. For Staphylococcus aureus, recurring infections and a limited success of vaccines containing S. aureus antigens imply that native antigens induce immune responses insufficient for optimal efficacy. These perspectives exemplify the need to apply novel vaccine strategies to high-priority pathogens. One such approach can be termed convergent immunity, where antigens from non-target organisms that contain epitope homologs found in the target organism are applied in vaccines. This approach aims to evoke atypical immune defenses via synergistic processes that (1) afford protective efficacy; (2) target an epitope from one organism that contributes to protective immunity against another; (3) cross-protect against multiple pathogens occupying a common anatomic or immunological niche; and/or (4) overcome immune subversion or avoidance strategies of target pathogens. Thus, convergent immunity has a potential to promote protective efficacy not usually elicited by native antigens from a target pathogen. Variations of this concept have been mainstays in the history of viral and bacterial vaccine development. A more far-reaching example is the pre-clinical evidence that specific fungal antigens can induce cross-kingdom protection against bacterial pathogens. This trans-kingdom protection has been demonstrated in pre-clinical studies of the recombinant Candida albicans agglutinin-like sequence 3 protein (rAls3) where it was shown that a vaccine containing rAls3 provides homologous protection against C. albicans, heterologous protection against several other Candida species, and convergent protection against several strains of S. aureus. Convergent immunity reflects an intriguing new approach to designing and developing vaccine antigens and is considered here in the context of vaccines to target S

Under-vaccinated groups in Europe and their beliefs, attitudes and reasons for non-vaccination; two systematic reviews.

PubMed

Fournet, N; Mollema, L; Ruijs, W L; Harmsen, I A; Keck, F; Durand, J Y; Cunha, M P; Wamsiedel, M; Reis, R; French, J; Smit, E G; Kitching, A; van Steenbergen, J E

2018-01-30

Despite effective national immunisation programmes in Europe, some groups remain incompletely or un-vaccinated ('under-vaccinated'), with underserved minorities and certain religious/ideological groups repeatedly being involved in outbreaks of vaccine preventable diseases (VPD). Gaining insight into factors regarding acceptance of vaccination of 'under-vaccinated groups' (UVGs) might give opportunities to communicate with them in a trusty and reliable manner that respects their belief system and that, maybe, increase vaccination uptake. We aimed to identify and describe UVGs in Europe and to describe beliefs, attitudes and reasons for non-vaccination in the identified UVGs. We defined a UVG as a group of persons who share the same beliefs and/or live in socially close-knit communities in Europe and who have/had historically low vaccination coverage and/or experienced outbreaks of VPDs since 1950. We searched MEDLINE, EMBASE and PsycINFO databases using specific search term combinations. For the first systematic review, studies that described a group in Europe with an outbreak or low vaccination coverage for a VPD were selected and for the second systematic review, studies that described possible factors that are associated with non-vaccination in these groups were selected. We selected 48 articles out of 606 and 13 articles out of 406 from the first and second search, respectively. Five UVGs were identified in the literature: Orthodox Protestant communities, Anthroposophists, Roma, Irish Travellers, and Orthodox Jewish communities. The main reported factors regarding vaccination were perceived non-severity of traditional "childhood" diseases, fear of vaccine side-effects, and need for more information about for example risk of vaccination. Within each UVG identified, there are a variety of health beliefs and objections to vaccination. In addition, similar factors are shared by several of these groups. Communication strategies regarding these similar factors such as

Mathematical modelling of respiratory syncytial virus (RSV): vaccination strategies and budget applications.

PubMed

Acedo, L; Díez-Domingo, J; Moraño, J-A; Villanueva, R-J

2010-06-01

We propose an age-structured mathematical model for respiratory syncytial virus in which children aged <1 year are especially considered. Real data on hospitalized children in the Spanish region of Valencia were used in order to determine some seasonal parameters of the model. Weekly predictions of the number of children aged <1 year that will be hospitalized in the following years in Valencia are presented using this model. Results are applied to estimate the regional cost of paediatric hospitalizations and to perform a cost-effectiveness analysis of possible vaccination strategies.

Economic Evaluation of Screening Strategies Combined with HPV Vaccination of Preadolescent Girls for the Prevention of Cervical Cancer in Vientiane, Lao PDR.

PubMed

Chanthavilay, Phetsavanh; Reinharz, Daniel; Mayxay, Mayfong; Phongsavan, Keokedthong; Marsden, Donald E; Moore, Lynne; White, Lisa J

2016-01-01

Several approaches to reduce the incidence of invasive cervical cancers exist. The approach adopted should take into account contextual factors that influence the cost-effectiveness of the available options. To determine the cost-effectiveness of screening strategies combined with a vaccination program for 10-year old girls for cervical cancer prevention in Vientiane, Lao PDR. A population-based dynamic compartment model was constructed. The interventions consisted of a 10-year old girl vaccination program only, or this program combined with screening strategies, i.e., visual inspection with acetic acid (VIA), cytology-based screening, rapid human papillomavirus (HPV) DNA testing, or combined VIA and cytology testing. Simulations were run over 100 years. In base-case scenario analyses, we assumed a 70% vaccination coverage with lifelong protection and a 50% screening coverage. The outcome of interest was the incremental cost per Disability-Adjusted Life Year (DALY) averted. In base-case scenarios, compared to the next best strategy, the model predicted that VIA screening of women aged 30-65 years old every three years, combined with vaccination, was the most attractive option, costing 2 544 international dollars (I$) per DALY averted. Meanwhile, rapid HPV DNA testing was predicted to be more attractive than cytology-based screening or its combination with VIA. Among cytology-based screening options, combined VIA with conventional cytology testing was predicted to be the most attractive option. Multi-way sensitivity analyses did not change the results. Compared to rapid HPV DNA testing, VIA had a probability of cost-effectiveness of 73%. Compared to the vaccination only option, the probability that a program consisting of screening women every five years would be cost-effective was around 60% and 80% if the willingness-to-pay threshold is fixed at one and three GDP per capita, respectively. A VIA screening program in addition to a girl vaccination program was

Benefit-Cost Analysis of Foot-and-Mouth Disease Vaccination at the Farm-Level in South Vietnam.

PubMed

Truong, Dinh Bao; Goutard, Flavie Luce; Bertagnoli, Stéphane; Delabouglise, Alexis; Grosbois, Vladimir; Peyre, Marisa

2018-01-01

This study aimed to analyze the financial impact of foot-and-mouth disease (FMD) outbreaks in cattle at the farm-level and the benefit-cost ratio (BCR) of biannual vaccination strategy to prevent and eradicate FMD for cattle in South Vietnam. Production data were collected from 49 small-scale dairy farms, 15 large-scale dairy farms, and 249 beef farms of Long An and Tay Ninh province using a questionaire. Financial data of FMD impacts were collected using participatory tools in 37 villages of Long An province. The net present value, i.e., the difference between the benefits (additional revenue and saved costs) and costs (additional costs and revenue foregone), of FMD vaccination in large-scale dairy farms was 2.8 times higher than in small-scale dairy farms and 20 times higher than in beef farms. The BCR of FMD vaccination over 1 year in large-scale dairy farms, small-scale dairy farms, and beef farms were 11.6 [95% confidence interval (95% CI) 6.42-16.45], 9.93 (95% CI 3.45-16.47), and 3.02 (95% CI 0.76-7.19), respectively. The sensitivity analysis showed that varying the vaccination cost had more effect on the BCR of cattle vaccination than varying the market price. This benefit-cost analysis of biannual vaccination strategy showed that investment in FMD prevention can be financially profitable, and therefore sustainable, for dairy farmers. For beef cattle, it is less certain that vaccination is profitable. Additional benefit-cost analysis study of vaccination strategies at the national-level would be required to evaluate and adapt the national strategy to achieve eradication of this disease in Vietnam.

Vaccine adjuvants: Why and how.

PubMed

Christensen, Dennis

2016-10-02

Novel vaccine strategies include the so-called subunit vaccines, which encompass only the part of the pathogen to which immune recognition results in protection. The high purity of these vaccines make adverse events less likely, but it also makes the vaccines less immunogenic and therefore potentially less effective. Vaccine adjuvants that increase and modulate the immunogenicity of the vaccine are therefore added to solve this problem. Besides aluminum salts, which have been used in vaccines for 90 years, a number of novel vaccine adjuvants have been included in licensed vaccines over the last 30 years. Increasing insight into immunological mechanisms and how to manipulate them has replaced empirical with rational design of adjuvants, leading to vaccine adjuvants with increased and customized immunogenicity profiles without compromising vaccine safety.

Cost-effectiveness of alternate strategies for childhood immunization against meningococcal disease with monovalent and quadrivalent conjugate vaccines in Canada.

PubMed

Delea, Thomas E; Weycker, Derek; Atwood, Mark; Neame, Dion; Alvarez, Fabián P; Forget, Evelyn; Langley, Joanne M; Chit, Ayman

2017-01-01

Public health programs to prevent invasive meningococcal disease (IMD) with monovalent serogroup C meningococcal conjugate vaccine (MCV-C) and quadrivalent meningococcal conjugate vaccines (MCV-4) in infancy and adolescence vary across Canadian provinces. This study evaluated the cost-effectiveness of various vaccination strategies against IMD using current and anticipated future pricing and recent epidemiology. A cohort model was developed to estimate the clinical burden and costs (CAN$2014) of IMD in the Canadian population over a 100-year time horizon for three strategies: (1) MCV-C in infants and adolescents (MCV-C/C); (2) MCV-C in infants and MCV-4 in adolescents (MCV-C/4); and (3) MCV-4 in infants (2 doses) and adolescents (MCV-4/4). The source for IMD incidence was Canadian surveillance data. The effectiveness of MCV-C was based on published literature. The effectiveness of MCV-4 against all vaccination regimens was assumed to be the same as for MCV-C regimens against serogroup C. Herd effects were estimated by calibration to estimates reported in prior analyses. Costs were from published sources. Vaccines prices were projected to decline over time reflecting historical procurement trends. Over the modeling horizon there are a projected 11,438 IMD cases and 1,195 IMD deaths with MCV-C/C; expected total costs are $597.5 million. MCV-C/4 is projected to reduce cases of IMD by 1,826 (16%) and IMD deaths by 161 (13%). Vaccination costs are increased by $32 million but direct and indirect IMD costs are projected to be reduced by $46 million. MCV-C/4 is therefore dominant vs. MCV-C/C in the base case. Cost-effectiveness of MCV-4/4 was $111,286 per QALY gained versus MCV-C/4 (2575/206 IMD cases/deaths prevented; incremental costs $68 million). If historical trends in Canadian vaccines prices continue, use of MCV-4 instead of MCV-C in adolescents may be cost-effective. From an economic perspective, switching to MCV-4 as the adolescent booster should be considered.

Prolonging herd immunity to cholera via vaccination: Accounting for human mobility and waning vaccine effects

PubMed Central

Buckee, Caroline O.

2018-01-01

Background Oral cholera vaccination is an approach to preventing outbreaks in at-risk settings and controlling cholera in endemic settings. However, vaccine-derived herd immunity may be short-lived due to interactions between human mobility and imperfect or waning vaccine efficacy. As the supply and utilization of oral cholera vaccines grows, critical questions related to herd immunity are emerging, including: who should be targeted; when should revaccination be performed; and why have cholera outbreaks occurred in recently vaccinated populations? Methods and findings We use mathematical models to simulate routine and mass oral cholera vaccination in populations with varying degrees of migration, transmission intensity, and vaccine coverage. We show that migration and waning vaccine efficacy strongly influence the duration of herd immunity while birth and death rates have relatively minimal impacts. As compared to either periodic mass vaccination or routine vaccination alone, a community could be protected longer by a blended “Mass and Maintain” strategy. We show that vaccination may be best targeted at populations with intermediate degrees of mobility as compared to communities with very high or very low population turnover. Using a case study of an internally displaced person camp in South Sudan which underwent high-coverage mass vaccination in 2014 and 2015, we show that waning vaccine direct effects and high population turnover rendered the camp over 80% susceptible at the time of the cholera outbreak beginning in October 2016. Conclusions Oral cholera vaccines can be powerful tools for quickly protecting a population for a period of time that depends critically on vaccine coverage, vaccine efficacy over time, and the rate of population turnover through human mobility. Due to waning herd immunity, epidemics in vaccinated communities are possible but become less likely through complementary interventions or data-driven revaccination strategies. PMID:29489815

Barriers and Facilitators to HPV Vaccination: Perspectives from Malawian Women

PubMed Central

Ports, Katie A.; Reddy, Diane M.; Rameshbabu, Anjali

2014-01-01

The aim of this research was to elucidate potential barriers and facilitators to human papillomavirus (HPV) vaccination in Malawi, a sub-Saharan country. In Malawi, approximately 31 out of every 100,000 women develop cervical cancer annually, and 80% of those affected die from this malignancy. HPV vaccination may provide a feasible strategy for cervical cancer prevention in Malawi. However, important questions and concerns regarding cervical cancer and HPV vaccination acceptance among individuals and their communities must be considered prior to vaccine delivery. Qualitative interviews were conducted with 30 Malawian mothers aged 18–49 years from Chiradzulu District. Women’s knowledge and beliefs about HPV, cervical cancer, and vaccination, and their social-ecological contexts were explored in-depth. Thematic analyses revealed that despite women’s limited knowledge, cervical cancer was perceived to be a serious disease. Participants believed that as women, they were responsible for their children’s health. Women unanimously reported that they would vaccinate their children against HPV, especially if a health professional recommended it. Malawi’s health care infrastructure could present challenges to HPV vaccine programs; however, participants did not typically report this to be a barrier to vaccination. These data shed light on factors that may influence HPV vaccination acceptance and uptake in Malawi. PMID:23937733

Advances in hepatitis C virus vaccines, part two: advances in hepatitis C virus vaccine formulations and modalities.

PubMed

Roohvand, Farzin; Kossari, Niloufar

2012-04-01

Developing a vaccine against HCV is an important medical and global priority. Unavailability and potential dangers associated with using attenuated HCV viral particles for vaccine preparation have resulted in the use of HCV genes and proteins formulated in novel vaccine modalities. In part one of this review, advances in basic knowledge for HCV vaccine design were provided. Herein, a detailed and correlated patents (searched by Espacenet) and literatures (searched by Pubmed) review on HCV vaccine formulations and modalities is provided, including: subunit, DNA, epitopic-peptide/polytopic, live vector- and whole yeast-based vaccines. Less-touched areas in vaccine studies such as mucosal, plant-based, and chimeric HBV/HCV vaccines are also discussed. Furthermore, results of preclinical/clinical studies on selected HCV vaccines as well as pros and cons of different strategies are reviewed. Finally, potential strategies for creation and/or improvement of HCV vaccine formulations are discussed. Promising outcomes of a few HCV vaccine modalities in phase I/II clinical trials predict the accessibility of at least partially effective vaccines to inhibit or treat the chronic state of HCV infection (specially in combination with standard antiviral therapy). ChronVac-C (plasmid DNA), TG4040 (MVA-based), and GI-5005 (whole yeast-based) might be the most obvious HCV vaccine candidates to be approved in the near future.

Formative research and development of an evidence-based communication strategy: the introduction of Vi typhoid fever vaccine among school-aged children in Karachi, Pakistan.

PubMed

Pach, Alfred; Tabbusam, Ghurnata; Khan, M Imran; Suhag, Zamir; Hussain, Imtiaz; Hussain, Ejaz; Mumtaz, Uzma; Haq, Inam Ul; Tahir, Rehman; Mirani, Amjad; Yousafzai, Aisha; Sahastrabuddhe, Sushant; Ochiai, R Leon; Soofi, Sajid; Clemens, John D; Favorov, Michael O; Bhutta, Zulfiqar A

2013-01-01

The authors conducted formative research (a) to identify stakeholders' concerns related to typhoid fever and the need for disease information and (b) to develop a communication strategy to inform stakeholders and address their concerns and motivate for support of a school-based vaccination program in Pakistan. Data were collected during interactive and semi-structured focus group discussions and interviews, followed by a qualitative analysis and multidisciplinary consultative process to identify an effective social mobilization strategy comprised of relevant media channels and messages. The authors conducted 14 focus group discussions with the parents of school-aged children and their teachers, and 13 individual interviews with school, religious, and political leaders. Parents thought that typhoid fever was a dangerous disease, but were unsure of their children's risk. They were interested in vaccination and were comfortable with a school-based vaccination if conducted under the supervision of trained and qualified staff. Teachers and leaders needed information on typhoid fever, the vaccine, procedures, and sponsors of the vaccination program. Meetings were considered the best form of information dissemination, followed by printed materials and mass media. This study shows how qualitative research findings can be translated into an effective social mobilization and communication approach. The findings of the research indicated the importance of increasing awareness of typhoid fever and the benefits of vaccination against the disease. Identification and dissemination of relevant, community-based disease and vaccination information will increase demand and use of vaccination.

How to Tackle Natural Focal Infections: From Risk Assessment to Vaccination Strategies.

PubMed

Busani, Luca; Platonov, Alexander E; Ergonul, Onder; Rezza, Giovanni

2017-01-01

Natural focal diseases are caused by biological agents associated with specific landscapes. The natural focus of such diseases is defined as any natural ecosystem containing the pathogen's population as an essential component. In such context, the agent circulates independently on human presence, and humans may become accidentally infected through contact with vectors or reservoirs. Some viruses (i.e., tick-borne encephalitis and Congo-Crimean hemorrhagic fever virus) are paradigmatic examples of natural focal diseases. When environmental changes, increase of reservoir/vector populations, demographic pressure, and/or changes in human behavior occur, increased risk of exposure to the pathogen may lead to clusters of cases or even to larger outbreaks. Intervention is often not highly cost-effective, thus only a few examples of large-scale or even targeted vaccination campaigns are reported in the international literature. To develop intervention models, risk assessment through disease mapping is an essential component of the response against these neglected threats and key to the design of prevention strategies, especially when effective vaccines against the disease are available.

Using YouTube to Disseminate Effective Vaccination Pain Treatment for Babies.

PubMed

Harrison, Denise; Wilding, Jodi; Bowman, Amanda; Fuller, Ann; Nicholls, Stuart G; Pound, Catherine M; Reszel, Jessica; Sampson, Margaret

2016-01-01

Infant vaccinations are necessary for public health, but are painful, causing distress to the infant and caregivers. Breastfeeding and sucrose effectively reduce infants' pain during vaccinations, and these strategies are recommended in health care provider (HCP)-targeted education and vaccination pain guidelines. However studies show these strategies are infrequently used. YouTube is a popular medium to publicly share and watch videos, and many consumer posted YouTube videos show distressed infants being vaccinated with no pain treatment. The aims of this study were to evaluate the reach and impact of a consumer-targeted YouTube video demonstrating use of effective pain reduction strategies during infant vaccinations. A brief consumer-targeted video showing two infants being vaccinated was posted onto YouTube on October 2013. One infant was breastfed and another infant received sucrose by mouth before and during the injection. A link to a viewer survey was visible on a banner near the end of the video. An intensive strategically planned knowledge dissemination strategy using the media, social media and messages to professional organizations took place to promote the video. Data analysis of the viewer survey, YouTube analytics of the reach of the video in terms of number of views, country of viewers, and comments relating to the video took place 12 months after the video was posted. Twelve months after posting, the video had 65,478views, 68 comments, 245 likes, 17 dislikes, and 90 shares. Average duration of viewer time was 65% of the video. The viewer survey was completed by 156 (0.24%) viewers; 90 (58%) answered as HCPs and 66 (42%) as parents. Survey results showed that the video was persuasive; intent to use or support breastfeeding or sucrose was high in both parents and HCPs after viewing the video. Comments posted were often emotional in nature, and were related to anti-vaccination (n = 26, 38%); effectiveness or positive personal experiences (n = 21, 32

Using YouTube to Disseminate Effective Vaccination Pain Treatment for Babies

PubMed Central

Harrison, Denise; Wilding, Jodi; Bowman, Amanda; Fuller, Ann; Nicholls, Stuart G.; Pound, Catherine M.; Reszel, Jessica; Sampson, Margaret

2016-01-01

Background Infant vaccinations are necessary for public health, but are painful, causing distress to the infant and caregivers. Breastfeeding and sucrose effectively reduce infants’ pain during vaccinations, and these strategies are recommended in health care provider (HCP)-targeted education and vaccination pain guidelines. However studies show these strategies are infrequently used. YouTube is a popular medium to publicly share and watch videos, and many consumer posted YouTube videos show distressed infants being vaccinated with no pain treatment. The aims of this study were to evaluate the reach and impact of a consumer-targeted YouTube video demonstrating use of effective pain reduction strategies during infant vaccinations. Methods A brief consumer-targeted video showing two infants being vaccinated was posted onto YouTube on October 2013. One infant was breastfed and another infant received sucrose by mouth before and during the injection. A link to a viewer survey was visible on a banner near the end of the video. An intensive strategically planned knowledge dissemination strategy using the media, social media and messages to professional organizations took place to promote the video. Data analysis of the viewer survey, YouTube analytics of the reach of the video in terms of number of views, country of viewers, and comments relating to the video took place 12 months after the video was posted. Results Twelve months after posting, the video had 65,478views, 68 comments, 245 likes, 17 dislikes, and 90 shares. Average duration of viewer time was 65% of the video. The viewer survey was completed by 156 (0.24%) viewers; 90 (58%) answered as HCPs and 66 (42%) as parents. Survey results showed that the video was persuasive; intent to use or support breastfeeding or sucrose was high in both parents and HCPs after viewing the video. Comments posted were often emotional in nature, and were related to anti-vaccination (n = 26, 38%); effectiveness or positive

Impact of committed individuals on vaccination behavior

NASA Astrophysics Data System (ADS)

Liu, Xiao-Tao; Wu, Zhi-Xi; Zhang, Lianzhong

2012-11-01

We study how the presence of committed vaccinators, a small fraction of individuals who consistently hold the vaccinating strategy and are immune to influence, impact the vaccination dynamics in well-mixed and spatially structured populations. For this purpose, we develop an epidemiological game-theoretic model of a flu-like vaccination by integrating an epidemiological process into a simple agent-based model of adaptive learning, where individuals (except for those committed ones) use anecdotal evidence to estimate costs and benefits of vaccination. We show that the committed vaccinators, acting as “steadfast role models” in the populations, can efficiently avoid the clustering of susceptible individuals and stimulate other imitators to take vaccination, hence contributing to the promotion of vaccine uptake. We substantiate our findings by making comparative studies of our model on a full lattice and on a randomly diluted one. Our work is expected to provide valuable information for decision-making and design more effective disease-control strategy.

Young multiethnic women's attitudes toward the HPV vaccine and HPV vaccination.

PubMed

Wong, Li Ping

2008-11-01

To investigate the acceptability of the HPV vaccine among a multiethnic sample of young women in Malaysia. A qualitative study of 40 young women aged between 13 and 27 years recruited into 7 focus groups to discuss their knowledge of HPV infection, and their attitudes toward and acceptance of the HPV vaccine. The women were divided into Malay, Chinese, and Indian groups to allow for comparison among ethnicities. Poor knowledge about HPV did not influence the HPV vaccine's acceptability. Although participants were in favor of the vaccine, the majority preferred to delay vaccination because it is newly introduced, they did not perceive themselves to be at risk of HPV infection, or because of cost factors. Concerns were raised regarding the vaccine's safety, the potential to be perceived as promiscuous and sexually active, and whether the vaccine was halal. Promotion of the HPV vaccine should take account of social and cultural acceptability. The findings will help develop strategies for effective vaccination initiatives in a multiethnic and multireligious Asian society.

Vaccines for viral diseases with dermatologic manifestations.

PubMed

Brentjens, Mathijs H; Yeung-Yue, Kimberly A; Lee, Patricia C; Tyring, Stephen K

2003-04-01

Vaccines against infectious diseases have been available since the 1800s, when an immunization strategy against smallpox developed by Jenner gained wide acceptance. Until recently, the only vaccination strategies available involved the use of protein-based, whole killed, and attenuated live virus vaccines. These strategies have led to the development of effective vaccines against a variety of diseases with primary or prominent cutaneous manifestations. Effective and safe vaccines now used worldwide include those directed against measles and rubella (now commonly used together with a mumps vaccine as the trivalent MMR), chickenpox, and hepatitis B. The eradication of naturally occurring smallpox remains one of the greatest successes in the history of modern medicine, but stockpiles of live smallpox exist in the United States and Russia. Renewed interest in the smallpox vaccine reflects concerns about a possible bioterrorist threat using this virus. Yellow fever is a hemorrhagic virus endemic to tropical areas of South America and Africa. An effective vaccine for this virus has existed since 1937, and it is used widely in endemic areas of South America, and to a lesser extent in Africa. This vaccine is recommended once every 10 years for people who are traveling to endemic areas. Advances in immunology have led to a greater understanding of immune system function in viral diseases. Progress in genetics and molecular biology has allowed researchers to design vaccines with novel mechanisms of action (eg, DNA, vector, and VLP vaccines). Vaccines have also been designed to specifically target particular viral components, allowing for stimulation of various arms of the immune system as desired. Ongoing research shows promise in prophylactic and therapeutic vaccination for viral infections with cutaneous manifestations. Further studies are necessary before vaccines for HSV, HPV, and HIV become commercially available.

Influenza vaccine response profiles are affected by vaccine preparation and preexisting immunity, but not HIV infection.

PubMed

Berger, Christoph T; Greiff, Victor; Mehling, Matthias; Fritz, Stefanie; Meier, Marc A; Hoenger, Gideon; Conen, Anna; Recher, Mike; Battegay, Manuel; Reddy, Sai T; Hess, Christoph

2015-01-01

Vaccines dramatically reduce infection-related morbidity and mortality. Determining factors that modulate the host response is key to rational vaccine design and demands unsupervised analysis. To longitudinally resolve influenza-specific humoral immune response dynamics we constructed vaccine response profiles of influenza A- and B-specific IgM and IgG levels from 42 healthy and 31 HIV infected influenza-vaccinated individuals. Pre-vaccination antibody levels and levels at 3 predefined time points after vaccination were included in each profile. We performed hierarchical clustering on these profiles to study the extent to which HIV infection associated immune dysfunction, adaptive immune factors (pre-existing influenza-specific antibodies, T cell responses), an innate immune factor (Mannose Binding Lectin, MBL), demographic characteristics (gender, age), or the vaccine preparation (split vs. virosomal) impacted the immune response to influenza vaccination. Hierarchical clustering associated vaccine preparation and pre-existing IgG levels with the profiles of healthy individuals. In contrast to previous in vitro and animal data, MBL levels had no impact on the adaptive vaccine response. Importantly, while HIV infected subjects with low CD4 T cell counts showed a reduced magnitude of their vaccine response, their response profiles were indistinguishable from those of healthy controls, suggesting quantitative but not qualitative deficits. Unsupervised profile-based analysis ranks factors impacting the vaccine-response by relative importance, with substantial implications for comparing, designing and improving vaccine preparations and strategies. Profile similarity between HIV infected and HIV negative individuals suggests merely quantitative differences in the vaccine response in these individuals, offering a rationale for boosting strategies in the HIV infected population.

Influenza Vaccine Research funded by the European Commission FP7-Health-2013-Innovation-1 project.

PubMed

Liu, Heng; Frijlink, Henderik W; Huckriede, Anke; van Doorn, Eva; Schmidt, Ed; Leroy, Odile; Rimmelzwaan, Guus; McCullough, Keneth; Whelan, Mike; Hak, Eelko

2016-11-21

Due to influenza viruses continuously displaying antigenic variation, current seasonal influenza vaccines must be updated annually to include the latest predicted strains. Despite all the efforts put into vaccine strain selection, vaccine production, testing, and administration, the protective efficacy of seasonal influenza vaccines is greatly reduced when predicted vaccine strains antigenically mismatch with the actual circulating strains. Moreover, preparing for a pandemic outbreak is a challenge, because it is unpredictable which strain will cause the next pandemic. The European Commission has funded five consortia on influenza vaccine development under the Seventh Framework Programme for Research and Technological Development (FP7) in 2013. The call of the EU aimed at developing broadly protective influenza vaccines. Here we review the scientific strategies used by the different consortia with respect to antigen selection, vaccine delivery system, and formulation. The issues related to the development of novel influenza vaccines are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

A two-dose heterologous prime-boost vaccine regimen eliciting sustained immune responses to Ebola Zaire could support a preventive strategy for future outbreaks

PubMed Central

Shukarev, Georgi; Callendret, Benoit; Luhn, Kerstin; Douoguih, Macaya

2017-01-01

ABSTRACT The consequences of the 2013–16 Ebola Zaire virus disease epidemic in West Africa were grave. The economies, healthcare systems and communities of Guinea, Sierra Leone and Liberia were devastated by over 18 months of active Ebola virus transmission, followed by sporadic resurgences potentially related to sexual transmission by survivors with viral persistence in body fluids following recovery. The need to develop and implement strategies to prevent and mitigate future outbreaks is now beyond dispute. The potential for unpredictable outbreaks of indeterminate duration, and control challenges posed by the possibility of sporadic re-emergence, mean that implementation of an effective vaccination program for outbreak containment necessitates a vaccine providing durable immunity. Heterologous prime-boost vaccine regimens deliver the same or similar antigens through different vaccine types, the first to prime and the second to boost the immune system. Ad26.ZEBOV/MVA-BN-Filo is an investigational Ebola Zaire vaccine regimen that uses this heterologous prime-boost approach. Preliminary Phase 1 data suggest that Ad26.ZEBOV/MVA-BN-Filo confers durable immunity for at least 240 d and is well-tolerated with a good safety profile. This regimen may therefore be suitable for prophylactic use in a regional or targeted population vaccination strategy, and could potentially aid prevention and control of future Ebola outbreaks. PMID:27925844

A two-dose heterologous prime-boost vaccine regimen eliciting sustained immune responses to Ebola Zaire could support a preventive strategy for future outbreaks.

PubMed

Shukarev, Georgi; Callendret, Benoit; Luhn, Kerstin; Douoguih, Macaya

2017-02-01

The consequences of the 2013-16 Ebola Zaire virus disease epidemic in West Africa were grave. The economies, healthcare systems and communities of Guinea, Sierra Leone and Liberia were devastated by over 18 months of active Ebola virus transmission, followed by sporadic resurgences potentially related to sexual transmission by survivors with viral persistence in body fluids following recovery. The need to develop and implement strategies to prevent and mitigate future outbreaks is now beyond dispute. The potential for unpredictable outbreaks of indeterminate duration, and control challenges posed by the possibility of sporadic re-emergence, mean that implementation of an effective vaccination program for outbreak containment necessitates a vaccine providing durable immunity. Heterologous prime-boost vaccine regimens deliver the same or similar antigens through different vaccine types, the first to prime and the second to boost the immune system. Ad26.ZEBOV/MVA-BN-Filo is an investigational Ebola Zaire vaccine regimen that uses this heterologous prime-boost approach. Preliminary Phase 1 data suggest that Ad26.ZEBOV/MVA-BN-Filo confers durable immunity for at least 240 d and is well-tolerated with a good safety profile. This regimen may therefore be suitable for prophylactic use in a regional or targeted population vaccination strategy, and could potentially aid prevention and control of future Ebola outbreaks.

Cost-effectiveness of vaccination against cervical cancer: a multi-regional analysis assessing the impact of vaccine characteristics and alternative vaccination scenarios.

PubMed

Suárez, Eugenio; Smith, Jennifer S; Bosch, F Xavier; Nieminen, Pekka; Chen, Chien-Jen; Torvinen, Saku; Demarteau, Nadia; Standaert, Baudouin

2008-09-15

Mathematical models provide valuable insights into the public health and economic impact of cervical cancer vaccination programmes. An in-depth economic analysis should explore the effects of different vaccine-related factors and vaccination scenarios (independent of screening practices) on health benefits and costs. In this analysis, a Markov cohort model was used to explore the impact of vaccine characteristics (e.g. cross-type protection and waning of immunity) and different vaccination scenarios (e.g. age at vaccination and multiple cohort strategies) on the cost-effectiveness results of cervical cancer vaccination programmes. The analysis was applied across different regions in the world (Chile, Finland, Ireland, Poland and Taiwan) to describe the influence of location-specific conditions. The results indicate that in all the different settings cervical cancer vaccination becomes more cost-effective with broader and sustained vaccine protection, with vaccination at younger ages, and with the inclusion of several cohorts. When other factors were varied, the cost-effectiveness of vaccination was most negatively impacted by increasing the discount rate applied to costs and health effects.

An estimate of the public health impact and cost-effectiveness of universal vaccination with a 9-valent HPV vaccine in Germany.

PubMed

Largeron, Nathalie; Petry, Karl Ulrich; Jacob, Jorge; Bianic, Florence; Anger, Delphine; Uhart, Mathieu

2017-02-01

Since 2007, the German Standing Vaccination Committee recommends HPV vaccination for girls aged 12-17 with a 2- (Cervarix®) or 4-valent (Gardasil®) vaccine. A 9-valent vaccine (Gardasil 9®) recently received a European market authorization in 2015. A dynamic transmission model was calibrated to the German setting and used to estimate costs and QALYs associated with vaccination strategies. Compared to the current vaccination program, the 9-valent vaccine extended to boys shows further reductions of 24% in the incidence of cervical cancer, 30% and 14% in anal cancer for males and females, as well as over a million cases of genital warts avoided after 100 years. The new strategy is associated with an ICER of 22,987€ per QALY gained, decreasing to 329€ when considering the vaccine switch for girls-only. Universal vaccination with the 9-valent vaccine can yield significant health benefits when compared to the current program.

Vaccines: the fourth century.

PubMed

Plotkin, Stanley A

2009-12-01

Vaccine development, which began with Edward Jenner's observations in the late 18th century, has entered its 4th century. From its beginnings, with the use of whole organisms that had been weakened or inactivated, to the modern-day use of genetic engineering, it has taken advantage of the tools discovered in other branches of microbiology. Numerous successful vaccines are in use, but the list of diseases for which vaccines do not exist is long. However, the multiplicity of strategies now available, discussed in this article, portends even more successful development of vaccines.

Perceptions matter: beliefs about influenza vaccine and vaccination behavior among elderly white, black and Hispanic Americans.

PubMed

Wooten, Karen G; Wortley, Pascale M; Singleton, James A; Euler, Gary L

2012-11-06

Knowledge and beliefs about influenza vaccine that differ across racial or ethnic groups may promote racial or ethnic disparities in vaccination. To identify associations between vaccination behavior and personal beliefs about influenza vaccine by race or ethnicity and education levels among the U.S. elderly population. Data from a national telephone survey conducted in 2004 were used for this study. Responses for 3875 adults ≥ 65 years of age were analyzed using logistic regression methods. Racial and ethnic differences in beliefs were observed. For example, whites were more likely to believe influenza vaccine is very effective in preventing influenza compared to blacks and Hispanics (whites, 60%; blacks, 47%, and Hispanics, 51%, p<0.01). Among adults who believed the vaccine is very effective, self-reported vaccination was substantially higher across all racial/ethnic groups (whites, 93%; blacks, 76%; Hispanics, 78%) compared to adults who believed the vaccine was only somewhat effective (whites 67%; blacks 61%, Hispanics 61%). Also, vaccination coverage differed by education level and personal beliefs of whites, blacks, and Hispanics. Knowledge and beliefs about influenza vaccine may be important determinants of influenza vaccination among racial/ethnic groups. Strategies to increase coverage should highlight the burden of influenza disease in racial and ethnic populations, the benefits and safety of vaccinations and personal vulnerability to influenza disease if not vaccinated. For greater effectiveness, factors associated with the education levels of some communities may need to be considered when developing or implementing new strategies that target specific racial or ethnic groups. Published by Elsevier Ltd.

Review: interventions to increase influenza vaccination among healthcare workers in hospitals

PubMed Central

Hollmeyer, Helge; Hayden, Frederick; Mounts, Anthony; Buchholz, Udo

2012-01-01

Please cite this paper as: Hollmeyer et al. (2012) Review: interventions to increase influenza vaccination among healthcare workers in hospitals. Influenza and Other Respiratory Viruses 7(4), 604–621. Annual influenza vaccination rates among hospital healthcare workers (HCW) are almost universally low despite recommendations from WHO and public health authorities in many countries. To assist in the development of successful vaccination programmes, we reviewed studies where interventions aimed to increase the uptake of influenza vaccination among hospital HCW. We searched PUBMED from 1990 up to December 2011 for publications with predetermined search strategies and of pre‐defined criteria for inclusion or exclusion. We evaluated a large number of ‘intervention programmes’ each employing one or more ‘intervention components’ or strategies, such as easy access to vaccine or educational activities, with the goal to raise influenza vaccine uptake rates in hospital HCW during one influenza season. Included studies reported results of intervention programmes and compared the uptake with the season prior to the intervention (historical control) or to another intervention programme within the same season that started from the same set of baseline activities. Twenty‐five studies performed in eight countries met our selection criteria and described 45 distinct intervention programmes. Most studies used their own facility as historical control and evaluated only one season. The following elements were used in intervention programmes that increased vaccine uptake: provision of free vaccine, easy access to the vaccine (e.g. through mobile carts or on‐site vaccination), knowledge and behaviour modification through educational activities and/or reminders and/or incentives, management or organizational changes, such as the assignment of personnel dedicated to the intervention programme, long‐term implementation of the strategy, requiring active declination and

Staying on track: a cluster randomized controlled trial of automated reminders aimed at increasing human papillomavirus vaccine completion.

PubMed

Patel, Ashlesha; Stern, Lisa; Unger, Zoe; Debevec, Elie; Roston, Alicia; Hanover, Rita; Morfesis, Johanna

2014-05-01

To evaluate whether automated reminders increase on-time completion of the three-dose human papillomavirus (HPV) vaccine series. Ten reproductive health centers enrolled 365 women aged 19-26 to receive dose one of the HPV vaccine. Health centers were matched and randomized so that participants received either routine follow-up (control) or automated reminder messages for vaccine doses two and three (intervention). Intervention participants selected their preferred method of reminders - text, e-mail, phone, private Facebook message, or standard mail. We compared vaccine completion rates between groups over a period of 32 weeks. The reminder system did not increase completion rates, which overall were low at 17.2% in the intervention group and 18.9% in the control group (p=0.881). Exploratory analyses revealed that participants who completed the series on-time were more likely to be older (OR=1.15, 95% CI 1.01-1.31), report having completed a four-year college degree or more (age-adjusted OR=2.51, 95% CI 1.29-4.90), and report three or more lifetime sexual partners (age-adjusted OR=3.45, 95% CI 1.20-9.92). The study intervention did not increase HPV vaccine series completion. Despite great public health interest in HPV vaccine completion and reminder technologies, completion rates remain low. Copyright © 2014 Elsevier Ltd. All rights reserved.

Military vaccines in today's environment.

PubMed

Schmaljohn, Connie S; Smith, Leonard A; Friedlander, Arthur M

2012-08-01

The US military has a long and highly distinguished record of developing effective vaccines against pathogens that threaten the armed forces. Many of these vaccines have also been of significant benefit to civilian populations around the world. The current requirements for force protection include vaccines against endemic disease threats as well as against biological warfare or bioterrorism agents, to include novel or genetically engineered threats. The cost of vaccine development and the modern regulatory requirements for licensing vaccines have strained the ability of the program to maintain this broad mission. Without innovative vaccine technologies, streamlined regulatory strategies, and coordinating efforts for use in civilian populations where appropriate, the military vaccine development program is in jeopardy.

Effectiveness of interventions that apply new media to improve vaccine uptake and vaccine coverage.

PubMed

Odone, Anna; Ferrari, Antonio; Spagnoli, Francesca; Visciarelli, Sara; Shefer, Abigail; Pasquarella, Cesira; Signorelli, Carlo

2015-01-01

Vaccine-preventable diseases (VPD) are still a major cause of morbidity and mortality worldwide. In high and middle-income settings, immunization coverage is relatively high. However, in many countries coverage rates of routinely recommended vaccines are still below the targets established by international and national advisory committees. Progress in the field of communication technology might provide useful tools to enhance immunization strategies. To systematically collect and summarize the available evidence on the effectiveness of interventions that apply new media to promote vaccination uptake and increase vaccination coverage. We conducted a systematic literature review. Studies published from January 1999 to September 2013 were identified by searching electronic resources (Pubmed, Embase), manual searches of references and expert consultation. Study setting We focused on interventions that targeted recommended vaccinations for children, adolescents and adults and: (1) aimed at increasing community demand for immunizations, or (2) were provider-based interventions. We limited the study setting to countries that are members of the Organisation for Economic Co-operation and Development (OECD). The primary outcome was a measure of vaccination (vaccine uptake or vaccine coverage). Considered secondary outcomes included willingness to receive immunization, attitudes and perceptions toward vaccination, and perceived helpfulness of the intervention. Nineteen studies were included in the systematic review. The majority of the studies were conducted in the US (74%, n = 14); 68% (n = 13) of the studies were experimental, the rest having an observational study design. Eleven (58%) reported results on the primary outcome. Retrieved studies explored the role of: text messaging (n.7, 37%), smartphone applications (n.1, 5%), Youtube videos (n.1, 5%), Facebook (n.1, 5%), targeted websites and portals (n.4, 21%), software for physicians and health professionals (n.4, 21

Effectiveness of interventions that apply new media to improve vaccine uptake and vaccine coverage

PubMed Central

Odone, Anna; Ferrari, Antonio; Spagnoli, Francesca; Visciarelli, Sara; Shefer, Abigail; Pasquarella, Cesira; Signorelli, Carlo

2014-01-01

Background Vaccine-preventable diseases (VPD) are still a major cause of morbidity and mortality worldwide. In high and middle-income settings, immunization coverage is relatively high. However, in many countries coverage rates of routinely recommended vaccines are still below the targets established by international and national advisory committees. Progress in the field of communication technology might provide useful tools to enhance immunization strategies. Objective To systematically collect and summarize the available evidence on the effectiveness of interventions that apply new media to promote vaccination uptake and increase vaccination coverage. Design We conducted a systematic literature review. Studies published from January 1999 to September 2013 were identified by searching electronic resources (Pubmed, Embase), manual searches of references and expert consultation. Study setting We focused on interventions that targeted recommended vaccinations for children, adolescents and adults and: (1) aimed at increasing community demand for immunizations, or (2) were provider-based interventions. We limited the study setting to countries that are members of the Organisation for Economic Co-operation and Development (OECD). Main outcome measures The primary outcome was a measure of vaccination (vaccine uptake or vaccine coverage). Considered secondary outcomes included willingness to receive immunization, attitudes and perceptions toward vaccination, and perceived helpfulness of the intervention. Results Nineteen studies were included in the systematic review. The majority of the studies were conducted in the US (74%, n = 14); 68% (n = 13) of the studies were experimental, the rest having an observational study design. Eleven (58%) reported results on the primary outcome. Retrieved studies explored the role of: text messaging (n.7, 37%), smartphone applications (n.1, 5%), Youtube videos (n.1, 5%), Facebook (n.1, 5%), targeted websites and portals (n.4, 21

Physician communication about adolescent vaccination: How is human papillomavirus vaccine different?

PubMed

Gilkey, Melissa B; Moss, Jennifer L; Coyne-Beasley, Tamera; Hall, Megan E; Shah, Parth D; Brewer, Noel T

2015-08-01

Low human papillomavirus (HPV) vaccination coverage stands in stark contrast to our success in delivering other adolescent vaccines. To identify opportunities for improving physicians' recommendations for HPV vaccination, we sought to understand how the communication context surrounding adolescent vaccination varies by vaccine type. A national sample of 776 U.S. physicians (53% pediatricians, 47% family medicine physicians) completed our online survey in 2014. We assessed physicians' perceptions and communication practices related to recommending adolescent vaccines for 11- and 12-year-old patients. About three-quarters of physicians (73%) reported recommending HPV vaccine as highly important for patients, ages 11-12. More physicians recommended tetanus, diphtheria, and acellular pertussis (Tdap) (95%) and meningococcal vaccines (87%, both p<0.001) as highly important for this age group. Only 13% of physicians perceived HPV vaccine as being highly important to parents, which was far fewer than perceived parental support for Tdap (74%) and meningococcal vaccines (62%, both p<0.001). Physicians reported that discussing HPV vaccine took almost twice as long as discussing Tdap. Among physicians with a preferred order for discussing adolescent vaccines, most (70%) discussed HPV vaccine last. Our findings suggest that primary care physicians perceived HPV vaccine discussions to be burdensome, requiring more time and engendering less parental support than other adolescent vaccines. Perhaps for this reason, physicians in our national study recommended HPV vaccine less strongly than other adolescent vaccines, and often chose to discuss it last. Communication strategies are needed to support physicians in recommending HPV vaccine with greater confidence and efficiency. Copyright © 2015 Elsevier Inc. All rights reserved.

Vaccine and adjuvant design for emerging viruses

PubMed Central

McAuley, Alexander J

2011-01-01

Vaccination is currently the most effective strategy to medically control viral diseases. However, developing vaccines is a long and expensive process and traditional methods, such as attenuating wild-type viruses by serial passage, may not be suitable for all viruses and may lead to vaccine safety considerations, particularly in the case of the vaccination of particular patient groups, such as the immunocompromised and the elderly. In particular, developing vaccines against emerging viral pathogens adds a further level of complexity, as they may only be administered to small groups of people or only in response to a specific event or threat, limiting our ability to study and evaluate responses. In this commentary, we discuss how novel techniques may be used to engineer a new generation of vaccine candidates as we move toward a more targeted vaccine design strategy, driven by our understanding of the mechanisms of viral pathogenesis, attenuation and the signaling events which are required to develop a lasting, protective immunity. We will also briefly discuss the potential future role of vaccine adjuvants, which could be used to bridge the gap between vaccine safety and lasting immunity from a single vaccination. PMID:21637006

Status of vaccine research and development of vaccines for GBS.

PubMed

Heath, Paul T

2016-06-03

Streptococcus agalactiae (group B streptococcus (GBS)) is the leading cause of neonatal sepsis and meningitis in many countries. Intrapartum antibiotic strategies have reduced the incidence of early-onset neonatal GBS in a number of countries but have had no impact on late onset GBS infection (LOD). In low/middle income settings, the disease burden remains uncertain although in several countries of Southern Africa appears comparable to or higher than that of high-income countries. As disease may be rapidly fulminating cases can be missed before appropriate samples are obtained and this may lead to underestimation of the true burden. Given the rapid onset and progression within hours of birth as well as the deficiencies in IAP strategies and absence of a solution for preventing LOD, it is clear that administration of a suitable vaccine in pregnancy could provide a better solution in all settings; it should also be cost effective. The current leading vaccine candidates are CPS-protein conjugate vaccines but protein-based vaccines are also in development and one has recently commenced clinical trials. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

`Quantum Mechanics' and `Scientific Explanation' An Explanatory Strategy Aiming at Providing `Understanding'