Dengue vaccine development: strategies and challenges.

PubMed

Ramakrishnan, Lakshmy; Pillai, Madhavan Radhakrishna; Nair, Radhakrishnan R

2015-03-01

Infection with dengue virus may result in dengue fever or a more severe outcome, such as dengue hemorrhagic syndrome/shock. Dengue virus infection poses a threat to endemic regions for four reasons: the presence of four serotypes, each with the ability to cause a similar disease outcome, including fatality; difficulties related to vector control; the lack of specific treatment; and the nonavailability of a suitable vaccine. Vaccine development is considered challenging due to the severity of the disease observed in individuals who have acquired dengue-specific immunity, either passively or actively. Therefore, the presence of vaccine-induced immunity against a particular serotype may prime an individual to severe disease on exposure to dengue virus. Vaccine development strategies include live attenuated vaccines, chimeric, DNA-based, subunit, and inactivated vaccines. Each of the candidates is in various stages of preclinical and clinical development. Issues pertaining to selection pressures, viral interaction, and safety still need to be evaluated in order to induce a complete protective immune response against all four serotypes. This review highlights the various strategies that have been employed in vaccine development, and identifies the obstacles to producing a safe and effective vaccine.

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

Evaluation of human papilloma virus (HPV) vaccination strategies and vaccination coverage in adolescent girls worldwide.

PubMed

Owsianka, Barbara; Gańczak, Maria

2015-01-01

An analysis of HPV vaccination strategies and vaccination coverage in adolescent girls worldwide for the last eight years with regard to potential improvement of vaccination coverage rates in Poland. Literature search, covering the period 2006-2014, was performed using Medline. Comparative analysis of HPV vaccination strategies and coverage between Poland and other countries worldwide was conducted. In the last eight years, a number of countries introduced HPV vaccination for adolescent girls to their national immunization programmes. Vaccination strategies differ, consequently affecting vaccination coverage, ranging from several percent to more than 90%. Usually, there are also disparities at national level. The highest HPV vaccination coverage rates are observed in countries where vaccines are administered in school settings and funded from the national budget. Poland is one of the eight EU countries where HPV vaccination has not been introduced to mandatory immunization programme and where paid vaccination is only provided in primary health care settings. HPV vaccination coverage in adolescent girls is estimated at 7.5-10%. Disparities in HPV vaccination coverage rates in adolescent girls worldwide may be due to different strategies of vaccination implementation between countries. Having compared to other countries, the low HPV vaccination coverage in Polish adolescent girls may result from the lack of funding at national level and the fact that vaccines are administered in a primary health care setting. A multidimensional approach, involving the engagement of primary health care and school personnel as well as financial assistance of government at national and local level and the implementation of media campaigns, particularly in regions with high incidence of cervical cancer, could result in an increase of HPV vaccination coverage rates in Poland.

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.

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.

Defending Against Smallpox: a Focus on Vaccines

PubMed Central

Voigt, Emily A.; Kennedy, Richard B.; Poland, Gregory A.

2016-01-01

Smallpox has shaped human history, from the earliest human civilizations well into the 20th century. With high mortality rates, rapid transmission, and serious long-term effects on survivors, smallpox was a much-feared disease. The eradication of smallpox represents an unprecedented medical victory for the lasting benefit of human health and prosperity. Concerns remain, however, about the development and use of the smallpox virus as a biological weapon, which necessitates the need for continued vaccine development. Smallpox vaccine development is thus a much-reviewed topic of high interest. This review focuses on the current state of smallpox vaccines and their context in biodefense efforts. PMID:27049653

Defending against smallpox: a focus on vaccines.

PubMed

Voigt, Emily A; Kennedy, Richard B; Poland, Gregory A

2016-09-01

Smallpox has shaped human history, from the earliest human civilizations well into the 20th century. With high mortality rates, rapid transmission, and serious long-term effects on survivors, smallpox was a much-feared disease. The eradication of smallpox represents an unprecedented medical victory for the lasting benefit of human health and prosperity. Concerns remain, however, about the development and use of the smallpox virus as a biological weapon, which necessitates the need for continued vaccine development. Smallpox vaccine development is thus a much-reviewed topic of high interest. This review focuses on the current state of smallpox vaccines and their context in biodefense efforts.

[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

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.

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.

[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

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.

Using Focus Groups to Validate a Pharmacy Vaccination Training Program.

PubMed

Bushell, Mary; Morrissey, Hana; Ball, Patrick

2015-06-12

Introduction: Focus group methodology is commonly used to quickly collate, integrated views from a variety of different stakeholders. This paper provides an example of how focus groups can be employed to collate expert opinion informing amendments on a newly developed training program for integration into undergraduate pharmacy curricula. Materials and methods: Four focus groups were conducted, across three continents, to determine the appropriateness and reliability of a developed vaccination training program with nested injection skills training. All focus groups were comprised of legitimate experts in the field of vaccination, medicine and/or pharmacy. Results: Themes that emerged across focus groups informed amendments giving rise to a validated version of a training program. Discussion : The rigorous validation of the vaccination training program offers generalizable lessons to inform the design and validation of future training programs intended for the health sector and or pharmacy curricula. Using the knowledge and experience of focus group participants fostered collaborative problem solving and validation of material and concept development. The group dynamics of a focus group allowed synthesis of feedback in an inter-professional manner. Conclusions : This paper provides a demonstration of how focus groups can be structured and used by health researchers to validate a newly developed training program.

Why parents refuse childhood vaccination: a qualitative study using online focus groups

PubMed Central

2013-01-01

Background In high income countries, vaccine-preventable diseases have been greatly reduced through routine vaccination programs. Despite this success, many parents question, and a small proportion even refuse vaccination for their children. As no qualitative studies have explored the factors behind these decisions among Dutch parents, we performed a study using online focus groups. Methods In total, eight online focus groups (n = 60) which included Dutch parents with at least one child, aged 0–4 years, for whom they refused all or part of the vaccinations within the National Immunization Program (NIP). A thematic analysis was performed to explore factors that influenced the parents’ decisions to refuse vaccination. Results Refusal of vaccination was found to reflect multiple factors including family lifestyle; perceptions about the child’s body and immune system; perceived risks of disease, vaccine efficacy, and side effects; perceived advantages of experiencing the disease; prior negative experience with vaccination; and social environment. The use of online focus groups proved to be an effective qualitative research method providing meaningful data. Conclusion Information provided by the NIP turned out to be insufficient for this group of parents. More trust in the NIP and deliberate decisions might result from increased parental understanding of lifestyle and disease susceptibility, the impact of vaccinations on the immune system, and the relative risks of diseases and their vaccines. The public health institute should also inform parents that the NIP is recommended but non-mandatory. PMID:24341406

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.

Leishmaniasis: focus on the design of nanoparticulate vaccine delivery systems.

PubMed

Doroud, Delaram; Rafati, Sima

2012-01-01

Although mass vaccination of the entire population of an endemic area would be the most cost-effective tool to diminish Leishmania burden, an effective vaccine is not yet commercially available. Practically, vaccines have failed to achieve the required level of protection, possibly owing to the lack of an appropriate adjuvant and/or delivery system. Therefore, there is still an imperative demand for an improved, safe and efficient delivery system to enhance the immunogenicity of available vaccine candidates. Nanoparticles are proficient in boosting the quality and magnitude of immune responses in a predictable fashion. Herein, we discuss how nanoparticulate vaccine delivery systems can be used to induce appropriate immune responses against leishmaniasis by controlling physicochemical properties of the vaccine. Stability, production reproducibility, low cost per dose and low risk-benefit ratios are desirable characteristics of an ideal vaccine formulation and solid lipid nanoparticles may serve as one of the most promising practical strategies to help to achieve such a leishmanial vaccine, at least in canine species in the developing world.

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.

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.

Parental regret regarding children's vaccines-The correlation between anticipated regret, altruism, coping strategies and attitudes toward vaccines.

PubMed

Hamama-Raz, Yaira; Ginossar-David, Eyal; Ben-Ezra, Menachem

2016-01-01

Parental hesitancy for recommended childhood vaccines is a growing public health concern influenced by various factors. This study aimed to explore regret regarding parental decisions to vaccinate their children via possible correlations between anticipated regret, altruism, coping strategies, and parents' attitudes toward the vaccination of their children. The study was conducted during 2014 in Israel. Data were collected via snowballing methodology (i.e., Internet forums, Facebook and e- mails). 314 parents of children ages 0-6 years participated in the study. Questionnaires were distributed and completed on-line including attitudes toward vaccines, altruism, coping strategies, regret and anticipated regret. Pearson analysis revealed a moderate negative association between attitudes toward vaccinations and regret. In addition, weak but significant positive associations emerged between anticipated regret and regret as well as between gender and regret. Performing hierarchical regression analysis revealed contribution of 35.9 % to the explained variance of regret suggesting that coping strategy of instrumental support, attitudes toward vaccinations and anticipated regret are linked significantly to regret. Parental attitudes toward vaccines and anticipated regret have a salient role when deciding whether or not to vaccinate children and contribute to the prediction of regret regarding vaccination. In order to increase parental consent to vaccination of their children, it is important to minimize possible regret through the strength of the recommendation and/or knowledge base about risk/benefit (perceived, heuristic) of vaccines that might influence parental attitudes and lessen their anticipated regret. N/A. This is not a clinical trial and thus does not require registration. Ethics approval was received from Ariel University School of Social Work Ethics committee (18/02/14). This was an attitude survey. The Ariel University School of Social Work Ethics committee

Cancer vaccines: an update with special focus on ganglioside antigens.

PubMed

Bitton, Roberto J; Guthmann, Marcel D; Gabri, Mariano R; Carnero, Ariel J L; Alonso, Daniel F; Fainboim, Leonardo; Gomez, Daniel E

2002-01-01

the (CIM) from La Havana, Cuba, to developed new strategies for specific active immunotherapy. The project included two ganglioside based vaccines and one anti-idiotypic vaccine. We focused on two antigens: first GM3, an ubiquitous antigen which is over-expressed in several epithelial tumor types; and a second one, N-Glycolyl-GM3 a more molecule, not being expressed in normal tissues and recently found in several neoplastic cells, in particular breast, melanoma and neuroectodermal cancer cells. We developed two vaccines, one with each antigen, both using proteins derived from the outer membrane proteins (OMP) of Neisseria Meningitidis B, as carriers. We developed also the 1E10 vaccine; an anti-idiotype vaccine designed to mimic the N-Glycolyl-GM3 gangliosides. This monoclonal antibody is an Ab2-type-antibody which recognizes the Ab1 antibody called P3, the latter is a monoclonal antibody that specifically recognizes gangliosides as antigens. Since 1998 we initiated a clinical development program for these three compounds. Results of the phase I clinical trials proved that the three vaccines were safe and able to elicit specific antibody responses. In addition we were able to demonstrate the activation of the cellular arm of the immune response in patients treated with the GM3 vaccine. Although phase I trials are not designed to evaluate antitumor efficacy, it was encouraging to observe tumor shrinkage in some patients treated both with the GM3 and N-Glycolyl-GM3 vaccines. We have already begun a phase II program in several neoplastic diseases, with all three vaccines.

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.

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.

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.

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

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

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.

The introduction of new vaccines into developing countries. IV: Global Access Strategies.

PubMed

Mahoney, Richard T; Krattiger, Anatole; Clemens, John D; Curtiss, Roy

2007-05-16

This paper offers a framework for managing a comprehensive Global Access Strategy for new vaccines in developing countries. It is aimed at strengthening the ability of public-sector entities to reach their goals. The Bill and Melinda Gates Foundation and The Rockefeller Foundation have been leaders in stimulating the creation of new organizations - public/private product development partnerships (PDPs) - that seek to accelerate vaccine development and distribution to meet the health needs of the world's poor. Case studies of two of these PDPs - the Salmonella Anti-pneumococcal Vaccine Program and the Pediatric Dengue Vaccine Initiative - examine development of such strategies. Relying on the application of innovation theory, the strategy leads to the identification of six Components of Innovation which cover all aspects of the vaccine innovation process. Appropriately modified, the proposed framework can be applied to the development and introduction of other products in developing countries including drugs, and nutritional and agricultural products.

Maternal knowledge and attitudes toward influenza vaccination: a focus group study in metropolitan Atlanta.

PubMed

Gazmararian, Julie A; Orenstein, Walter; Prill, Mila; Hitzhusen, Hannah B; Coleman, Margaret S; Pazol, Karen; Oster, Natalia V

2010-11-01

To explore the knowledge and attitudes of mothers of school-aged children toward influenza vaccination and assess what methods of communication about vaccination and its delivery work best among this audience. The authors conducted focus groups with mothers of school-aged children. Prior to the focus groups, investigators agreed on key themes and discussion points. They independently reviewed transcripts using systematic content analysis and came to an agreement on outcome themes. Many study participants had misunderstandings about influenza vaccines and the definition of influenza. A common perception was that flu is a catch-all term for a variety of undefined illnesses, ranging from a severe cold to stomach upset. Few participants saw a societal benefit in vaccinating children to protect other populations (eg, the elderly). This study represents a first step in understanding how mothers perceive influenza vaccination and for crafting effective communication to increase vaccination among school-aged children.

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

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.

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

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

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

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.

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.

Low rate of human papillomavirus vaccination among schoolgirls in Lebanon: barriers to vaccination with a focus on mothers’ knowledge about available vaccines

PubMed Central

Abou El-Ola, Maria J; Rajab, Mariam A; Abdallah, Dania I; Fawaz, Ismail A; Awad, Lyn S; Tamim, Hani M; Ibrahim, Ahmad O; Mugharbil, Anas M; Moghnieh, Rima A

2018-01-01

important one is the mothers’ lack of knowledge about HPV, cervical cancer, and the modes of prevention. Awareness campaigns along with a multimodal strategy that targets the identified barriers would be recommended to achieve higher rates of HPV vaccination. PMID:29628765

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.

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.

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

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.

[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.

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

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

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

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.

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

Communication strategies to promote the uptake of childhood vaccination in Nigeria: a systematic map.

PubMed

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

2016-01-01

Effective communication is a critical component in ensuring that children are fully vaccinated. Although numerous communication interventions have been proposed and implemented in various parts of Nigeria, the range of communication strategies used has not yet been mapped systematically. This study forms part of the 'Communicate to vaccinate' (COMMVAC) project, an initiative aimed at building research evidence for improving communication with parents and communities about childhood vaccinations in low- and middle-income countries. This study aims to: 1) identify the communication strategies used in two states in Nigeria; 2) map these strategies against the existing COMMVAC taxonomy, a global taxonomy of vaccination communication interventions; 3) create a specific Nigerian country map of interventions organised by purpose and target; and 4) analyse gaps between the COMMVAC taxonomy and the Nigerian map. We conducted the study in two Nigerian states: Bauchi State in Northern Nigeria and Cross River State in Southern Nigeria. We identified vaccination communication interventions through interviews carried out among purposively selected stakeholders in the health services and relevant agencies involved in vaccination information delivery; through observations and through relevant documents. We used the COMMVAC taxonomy to organise the interventions we identified based on the intended purpose of the communication and the group to which the intervention was targeted. The Nigerian map revealed that most of the communication strategies identified aimed to inform and educate and remind or recall. Few aimed to teach skills, enhance community ownership, and enable communication. We did not identify any intervention that aimed to provide support or facilitate decision-making. Many interventions had more than one purpose. The main targets for most interventions were caregivers and community members, with few interventions directed at health workers. Most interventions

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

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.

New vaccines against influenza virus

PubMed Central

Lee, Young-Tae; Kim, Ki-Hye; Ko, Eun-Ju; Lee, Yu-Na; Kim, Min-Chul; Kwon, Young-Man; Tang, Yinghua; Cho, Min-Kyoung; Lee, Youn-Jeong

2014-01-01

Vaccination is one of the most effective and cost-benefit interventions that prevent the mortality and reduce morbidity from infectious pathogens. However, the licensed influenza vaccine induces strain-specific immunity and must be updated annually based on predicted strains that will circulate in the upcoming season. Influenza virus still causes significant health problems worldwide due to the low vaccine efficacy from unexpected outbreaks of next epidemic strains or the emergence of pandemic viruses. Current influenza vaccines are based on immunity to the hemagglutinin antigen that is highly variable among different influenza viruses circulating in humans and animals. Several scientific advances have been endeavored to develop universal vaccines that will induce broad protection. Universal vaccines have been focused on regions of viral proteins that are highly conserved across different virus subtypes. The strategies of universal vaccines include the matrix 2 protein, the hemagglutinin HA2 stalk domain, and T cell-based multivalent antigens. Supplemented and/or adjuvanted vaccination in combination with universal target antigenic vaccines would have much promise. This review summarizes encouraging scientific advances in the field with a focus on novel vaccine designs. PMID:24427759

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.

Focusing on flu: Parent perspectives on school-located immunization programs for influenza vaccine.

PubMed

Middleman, Amy B; Short, Mary B; Doak, Jean S

2012-10-01

School-located immunization programs (SLIP) will only be successful if parents consent to their children's participation. It is critical to understand parent perspectives regarding the factors that make them more or less likely to provide that consent. Organizations creating SLIPs will be able to capitalize on the aspects of SLIPs that parents appreciate, and address and correct issues that may give rise to parent concerns. This study involved five focus groups among the parents of school students in a large, urban school district. Findings highlight the broad range of concepts important to parents when considering participation in a SLIP. The safety and trust issues regarding vaccines in general that are so important to parents are also important to parents when considering participation in a SLIP. Effective communication strategies that include assurances regarding tracking of information and the competence and experience of immunizers will be helpful when addressing parents regarding SLIPs. In addition, parents were very cognizant of and positive regarding the public health benefits associated with SLIPs. Further study among larger populations of parents will further refine these ideas and aid in the development of successful influenza vaccine SLIPs that directly address and communicate with parents about the issues most important to them.

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.

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

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.

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

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

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.

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.

HIV vaccines: new frontiers in vaccine development.

PubMed

Duerr, Ann; Wasserheit, Judith N; Corey, Lawrence

2006-08-15

A human immunodeficiency virus (HIV) vaccine is the most promising and feasible strategy to prevent the events during acute infection that simultaneously set the course of the epidemic in the community and the course of the disease for the individual. Because safety concerns limit the use of live, attenuated HIV and inactivated HIV, a variety of alternate approaches is being investigated. Traditional antibody-mediated approaches using recombinant HIV envelope proteins have shown no efficacy in 2 phase III trials. Current HIV vaccine trials are focusing primarily on cytotoxic T lymphocyte-mediated products that use viral vectors, either alone or as boosts to DNA plasmids that contain viral genes. The most immunogenic of these products appear to be the recombinant adenovirus vector vaccines, 2 of which are now in advanced clinical development.

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.

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

Vaccination against Alzheimer disease: an update on future strategies.

PubMed

Fettelschoss, Antonia; Zabel, Franziska; Bachmann, Martin F

2014-01-01

Alzheimer disease is a devastating chronic disease without adequate therapy. More than 10 years ago, it was demonstrated in transgenic mouse models that vaccination may be a novel, disease-modifying therapy for Alzheimer. Subsequent clinical development has been a roller-coaster with some positive and many negative news. Here, we would like to summarize evidence that next generation vaccines optimized for old people and focusing on patients with mild disease stand a good chance to proof efficacious for the treatment of Alzheimer.

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.

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

Communication strategies to promote the uptake of childhood vaccination in Nigeria: a systematic map

PubMed Central

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

2016-01-01

Background Effective communication is a critical component in ensuring that children are fully vaccinated. Although numerous communication interventions have been proposed and implemented in various parts of Nigeria, the range of communication strategies used has not yet been mapped systematically. This study forms part of the ‘Communicate to vaccinate’ (COMMVAC) project, an initiative aimed at building research evidence for improving communication with parents and communities about childhood vaccinations in low- and middle-income countries. Objective This study aims to: 1) identify the communication strategies used in two states in Nigeria; 2) map these strategies against the existing COMMVAC taxonomy, a global taxonomy of vaccination communication interventions; 3) create a specific Nigerian country map of interventions organised by purpose and target; and 4) analyse gaps between the COMMVAC taxonomy and the Nigerian map. Design We conducted the study in two Nigerian states: Bauchi State in Northern Nigeria and Cross River State in Southern Nigeria. We identified vaccination communication interventions through interviews carried out among purposively selected stakeholders in the health services and relevant agencies involved in vaccination information delivery; through observations and through relevant documents. We used the COMMVAC taxonomy to organise the interventions we identified based on the intended purpose of the communication and the group to which the intervention was targeted. Results The Nigerian map revealed that most of the communication strategies identified aimed to inform and educate and remind or recall. Few aimed to teach skills, enhance community ownership, and enable communication. We did not identify any intervention that aimed to provide support or facilitate decision-making. Many interventions had more than one purpose. The main targets for most interventions were caregivers and community members, with few interventions directed at

Five focus strategies to organize health care delivery.

PubMed

Peltokorpi, Antti; Linna, Miika; Malmström, Tomi; Torkki, Paulus; Lillrank, Paul Martin

2016-01-01

The focused factory is one of the concepts that decision-makers have adopted for improving health care delivery. However, disorganized definitions of focus have led to findings that cannot be utilized systematically. The purpose of this paper is to discuss strategic options to focus health care operations. First the literature on focus in health care is reviewed revealing conceptual challenges. Second, a definition of focus in terms of demand and requisite variety is defined, and the mechanisms of focus are explicated. A classification of five focus strategies that follow the original idea to reduce variety in products and markets is presented. Finally, the paper examines managerial possibilities linked to the focus strategies. The paper proposes a framework of five customer-oriented focus strategies which aim at reducing variety in different characteristics of care pathways: population; urgency and severity; illnesses and symptoms; care practices and processes; and care outcomes. Empirical research is needed to evaluate the costs and benefits of the five strategies and about system-level effects of focused units on competition and coordination. Focus is an enabling condition that needs to be exploited using specific demand and supply management practices. It is essential to understand how focus mechanisms differ between strategies, and to select focus that fits with organization's strategy and key performance indicators. Compared to previous more resource-oriented approaches, this study provides theoretically solid and practically relevant customer-oriented framework for focusing in health care.

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.

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.

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.

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.

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

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.

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.

Preparing for human papillomavirus vaccine introduction in Kenya: implications from focus-group and interview discussions with caregivers and opinion leaders in Western Kenya.

PubMed

Friedman, Allison L; Oruko, Kelvin O; Habel, Melissa A; Ford, Jessie; Kinsey, Jennine; Odhiambo, Frank; Phillips-Howard, Penelope A; Wang, Susan A; Collins, Tabu; Laserson, Kayla F; Dunne, Eileen F

2014-08-16

Cervical cancer claims the lives of 275,000 women each year; most of these deaths occur in low-or middle-income countries. In Kenya, cervical cancer is the leading cause of cancer-related mortality among women of reproductive age. Kenya's Ministry of Public Health and Sanitation has developed a comprehensive strategy to prevent cervical cancer, which includes plans for vaccinating preteen girls against human papillomavirus (HPV) by 2015. To identify HPV vaccine communication and mobilization needs, this research sought to understand HPV vaccine-related perceptions and concerns of male and female caregivers and community leaders in four rural communities of western Kenya. We conducted five focus groups with caregivers (n = 56) and 12 key-informant interviews with opinion leaders to explore cervical cancer-related knowledge, attitudes and beliefs, as well as acceptability of HPV vaccination for 9-12 year-old girls. Four researchers independently reviewed the data and developed codes based on questions in interview guides and topics that emerged organically, before comparing and reconciling results through a group consensus process. Cervical cancer was not commonly recognized, though it was understood generally in terms of its symptoms. By association with cancer and genital/reproductive organs, cervical cancer was feared and stigmatized. Overall acceptability of a vaccine that prevents cervical cancer was high, so long as it was endorsed by trusted agencies and communities were sensitized first. Some concerns emerged related to vaccine safety (e.g., impact on fertility), program intent, and health equity. For successful vaccine introduction in Kenya, there is a need for communication and mobilization efforts to raise cervical cancer awareness; prompt demand for vaccination; address health equity concerns and stigma; and minimize potential resistance. Visible endorsement by government leaders and community influencers can provide reassurance of the vaccine's safety

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

Epidemiological and evolutionary consequences of targeted vaccination.

PubMed

Williams, Paul D; Day, Troy

2008-01-01

Recent theory has examined the way in which vaccination strategies are expected to influence the evolution of parasite virulence. Most of this work has assumed that vaccination is imposed on a homogeneous host population. However, host populations are typically composed of different types of individuals, with each type responding differently to infection. Moreover, actual interventions often focus treatment on those hosts that are likely to suffer the most ill effects of a particular disease. Here we consider the epidemiological and evolutionary consequences of interventions that focus vaccination on individuals expressing the greatest susceptibility to infection and/or the greatest vulnerability to mortality once infected. Our results indicate that predictions are very sensitive to the nature and degree of heterogeneity in susceptibility and vulnerability. They further suggest that accounting for realistic kinds of heterogeneity when contemplating targeted treatment plans and policies might provide a new tool in the design of more effective virulence management strategies.

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.

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.

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

Experimental vaccines against potentially pandemic and highly pathogenic avian influenza viruses

PubMed Central

Mooney, Alaina J; Tompkins, S Mark

2013-01-01

Influenza A viruses continue to emerge and re-emerge, causing outbreaks, epidemics and occasionally pandemics. While the influenza vaccines licensed for public use are generally effective against seasonal influenza, issues arise with production, immunogenicity, and efficacy in the case of vaccines against pandemic and emerging influenza viruses, and highly pathogenic avian influenza virus in particular. Thus, there is need of improved influenza vaccines and vaccination strategies. This review discusses advances in alternative influenza vaccines, touching briefly on licensed vaccines and vaccine antigens; then reviewing recombinant subunit vaccines, virus-like particle vaccines and DNA vaccines, with the main focus on virus-vectored vaccine approaches. PMID:23440999

Aging of the immune system – focus on inflammation and vaccination

PubMed Central

Pinti, Marcello; Appay, Victor; Campisi, Judith; Frasca, Daniela; Fülöp, Tamas; Sauce, Delphine; Larbi, Anis; Weinberger, Birgit; Cossarizza, Andrea

2016-01-01

Major advances in preventing, delaying or curing individual pathologies are responsible for an increasingly long life span in the developed parts of our planet, and indeed reaching 8–9 decades of life is nowadays extremely frequent. However, medical and sanitary advances have not prevented or delayed the underlying cause of the disparate pathologies occurring in the elderly: aging itself. The identification of the basis of the aging processes that drives the multiple pathologies and loss of function typical of older individuals is a major challenge in current aging research. Among the possible causes, an impairment of the immune system plays a major role, and indeed numerous studies have described immunological changes which occur with age. Far from the intention of being exhaustive, this review will focus on recent advances and views on the role that modifications of cell signalling and remodelling of the immune response play during human aging and longevity, paying particular attention to phenomena which are linked to the so called inflammaging process, such as dysregulation of innate immunity, altered T-cell or B-cell maturation and differentiation, as well as to the implications of immune aging for vaccination strategies in the elderly. PMID:27595500

Routinely vaccinating adolescents against meningococcus: targeting transmission & disease.

PubMed

Vetter, Volker; Baxter, Roger; Denizer, Gülhan; Sáfadi, Marco A P; Silfverdal, Sven-Arne; Vyse, Andrew; Borrow, Ray

2016-05-01

Adolescents have the highest rates of meningococcal carriage and transmission. Interrupting the adolescent habitat in order to reduce carriage and transmission within adolescents and to other age groups could help to control meningococcal disease at a population level. Compared to immunization strategies restricted to young children, a strategy focused on adolescents may have more profound and long-lasting indirect impacts, and may be more cost effective. Despite challenges in reaching this age-group, experience with other vaccines show that high vaccine coverage of adolescents is attainable.

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.

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

Factors Associated with Intention to Receive Influenza and Tetanus, Diphtheria, and Acellular Pertussis (Tdap) Vaccines during Pregnancy: A Focus on Vaccine Hesitancy and Perceptions of Disease Severity and Vaccine Safety.

PubMed

Chamberlain, Allison T; Seib, Katherine; Ault, Kevin A; Orenstein, Walter A; Frew, Paula M; Malik, Fauzia; Cortés, Marielysse; Cota, Pat; Whitney, Ellen A S; Flowers, Lisa C; Berkelman, Ruth L; Omer, Saad B

2015-02-25

Improving influenza and tetanus, diphtheria and acellular pertussis (Tdap) vaccine coverage among pregnant women is needed. To assess factors associated with intention to receive influenza and/or Tdap vaccinations during pregnancy with a focus on perceptions of influenza and pertussis disease severity and influenza vaccine safety. Participants were 325 pregnant women in Georgia recruited from December 2012 - April 2013 who had not yet received a 2012/2013 influenza vaccine or a Tdap vaccine while pregnant. Women completed a survey assessing influenza vaccination history, likelihood of receiving antenatal influenza and/or Tdap vaccines, and knowledge, attitudes and beliefs about influenza, pertussis, and their associated vaccines. Seventy-three percent and 81% of women believed influenza and pertussis, respectively, would be serious during pregnancy while 87% and 92% believed influenza and pertussis, respectively, would be serious to their infants. Perception of pertussis severity for their infant was strongly associated with an intention to receive a Tdap vaccine before delivery (p=0.004). Despite perceptions of disease severity for themselves and their infants, only 34% and 44% intended to receive antenatal influenza and Tdap vaccines, respectively. Forty-six percent had low perceptions of safety regarding the influenza vaccine during pregnancy, and compared to women who perceived the influenza vaccine as safe, women who perceived the vaccine as unsafe were less likely to intend to receive antenatal influenza (48% vs. 20%; p < 0.001) or Tdap (53% vs. 33%; p < 0.001) vaccinations. Results from this baseline survey suggest that while pregnant women who remain unvaccinated against influenza within the first three months of the putative influenza season may be aware of the risks influenza and pertussis pose to themselves and their infants, many remain reluctant to receive influenza and Tdap vaccines antenatally. To improve vaccine uptake in the obstetric setting, our

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.

Vaccination decision-making of immigrant parents in the Netherlands; a focus group study.

PubMed

Harmsen, Irene A; Bos, Helien; Ruiter, Robert A C; Paulussen, Theo G W; Kok, Gerjo; de Melker, Hester E; Mollema, Liesbeth

2015-12-10

Although the vaccination coverage in most high income countries is high, variations in coverage rates on the national level among different ethnic backgrounds are reported. A qualitative study was performed to explore factors that influence decision-making among parents with different ethnic backgrounds in the Netherlands. Six focus groups were conducted with 33 mothers of Moroccan, Turkish and other ethnic backgrounds with at least one child aged 0-4 years. Data were analysed using thematic analysis. Parents had a positive attitude towards childhood vaccination and a high confidence in the advices of Child Vaccine Providers (CVPs). Vaccinating their children was perceived as self-evident and important. Parents do perceive a language barrier in understanding the provided NIP-information, and they had a need for more NIP- information, particularly about the targeted diseases. Another barrier parents perceived was the distance to the Child Welfare Center (CWC), especially when the weather was bad and when they had no access to a car. More information about targeted diseases and complete information regarding benefits and drawbacks of the NIP should be provided to the parents. To fulfill parents' information needs, NIP information meetings can be organized at CWCs in different languages. Providing NIP information material in Turkish, Arabic and Berber language with easy access is also recommended. Providing information tailored to these parents' needs is important to sustain high vaccination participation, and to ensure acceptance of future vaccinations.

Vaccines against poverty

PubMed Central

MacLennan, Calman A.; Saul, Allan

2014-01-01

With the 2010s declared the Decade of Vaccines, and Millennium Development Goals 4 and 5 focused on reducing diseases that are potentially vaccine preventable, now is an exciting time for vaccines against poverty, that is, vaccines against diseases that disproportionately affect low- and middle-income countries (LMICs). The Global Burden of Disease Study 2010 has helped better understand which vaccines are most needed. In 2012, US$1.3 billion was spent on research and development for new vaccines for neglected infectious diseases. However, the majority of this went to three diseases: HIV/AIDS, malaria, and tuberculosis, and not neglected diseases. Much of it went to basic research rather than development, with an ongoing decline in funding for product development partnerships. Further investment in vaccines against diarrheal diseases, hepatitis C, and group A Streptococcus could lead to a major health impact in LMICs, along with vaccines to prevent sepsis, particularly among mothers and neonates. The Advanced Market Commitment strategy of the Global Alliance for Vaccines and Immunisation (GAVI) Alliance is helping to implement vaccines against rotavirus and pneumococcus in LMICs, and the roll out of the MenAfriVac meningococcal A vaccine in the African Meningitis Belt represents a paradigm shift in vaccines against poverty: the development of a vaccine primarily targeted at LMICs. Global health vaccine institutes and increasing capacity of vaccine manufacturers in emerging economies are helping drive forward new vaccines for LMICs. Above all, partnership is needed between those developing and manufacturing LMIC vaccines and the scientists, health care professionals, and policy makers in LMICs where such vaccines will be implemented. PMID:25136089

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

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.

Routinely vaccinating adolescents against meningococcus: targeting transmission & disease

PubMed Central

Vetter, Volker; Baxter, Roger; Denizer, Gülhan; Sáfadi, Marco A. P.; Silfverdal, Sven-Arne; Vyse, Andrew; Borrow, Ray

2016-01-01

ABSTRACT Adolescents have the highest rates of meningococcal carriage and transmission. Interrupting the adolescent habitat in order to reduce carriage and transmission within adolescents and to other age groups could help to control meningococcal disease at a population level. Compared to immunization strategies restricted to young children, a strategy focused on adolescents may have more profound and long-lasting indirect impacts, and may be more cost effective. Despite challenges in reaching this age-group, experience with other vaccines show that high vaccine coverage of adolescents is attainable. PMID:26651380

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

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.

The Effectiveness of Influenza Vaccination in Different Groups.

PubMed

Domínguez, Angela; Godoy, Pere; Torner, Nuria

2016-06-01

Annual administration of the seasonal influenza vaccine, especially to persons known to be at elevated risk for developing serious complications, is the focus of current efforts to reduce the impact of influenza. The main factors influencing estimated inactivated influenza vaccine efficacy and effectiveness, the results obtained in different population groups, current vaccination strategies and the possible advantages of new vaccines are discussed. The available evidence suggests that influenza vaccines are less effective in the elderly than in young adults, but vaccination is encouraged by public health institutions due to higher mortality and complications. There is no consensus on universal vaccination of children yet economic studies suggest that yearly paediatric vaccination is cost saving. The benefits of herd immunity generated by paediatric vaccination require further study. Newer vaccines should be more and more-broadly protective, stable, easy to manufacture and administer and highly immunogenic across all population groups.

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.

Vaccination against Salmonella Infection: the Mucosal Way.

PubMed

Gayet, Rémi; Bioley, Gilles; Rochereau, Nicolas; Paul, Stéphane; Corthésy, Blaise

2017-09-01

Salmonella enterica subspecies enterica includes several serovars infecting both humans and other animals and leading to typhoid fever or gastroenteritis. The high prevalence of associated morbidity and mortality, together with an increased emergence of multidrug-resistant strains, is a current global health issue that has prompted the development of vaccination strategies that confer protection against most serovars. Currently available systemic vaccine approaches have major limitations, including a reduced effectiveness in young children and a lack of cross-protection among different strains. Having studied host-pathogen interactions, microbiologists and immunologists argue in favor of topical gastrointestinal administration for improvement in vaccine efficacy. Here, recent advances in this field are summarized, including mechanisms of bacterial uptake at the intestinal epithelium, the assessment of protective host immunity, and improved animal models that closely mimic infection in humans. The pros and cons of existing vaccines are presented, along with recent progress made with novel formulations. Finally, new candidate antigens and their relevance in the refined design of anti- Salmonella vaccines are discussed, along with antigen vectorization strategies such as nanoparticles or secretory immunoglobulins, with a focus on potentiating mucosal vaccine efficacy. Copyright © 2017 American Society for Microbiology.

Efficient Vaccine Distribution Based on a Hybrid Compartmental Model.

PubMed

Yu, Zhiwen; Liu, Jiming; Wang, Xiaowei; Zhu, Xianjun; Wang, Daxing; Han, Guoqiang

2016-01-01

To effectively and efficiently reduce the morbidity and mortality that may be caused by outbreaks of emerging infectious diseases, it is very important for public health agencies to make informed decisions for controlling the spread of the disease. Such decisions must incorporate various kinds of intervention strategies, such as vaccinations, school closures and border restrictions. Recently, researchers have paid increased attention to searching for effective vaccine distribution strategies for reducing the effects of pandemic outbreaks when resources are limited. Most of the existing research work has been focused on how to design an effective age-structured epidemic model and to select a suitable vaccine distribution strategy to prevent the propagation of an infectious virus. Models that evaluate age structure effects are common, but models that additionally evaluate geographical effects are less common. In this paper, we propose a new SEIR (susceptible-exposed-infectious šC recovered) model, named the hybrid SEIR-V model (HSEIR-V), which considers not only the dynamics of infection prevalence in several age-specific host populations, but also seeks to characterize the dynamics by which a virus spreads in various geographic districts. Several vaccination strategies such as different kinds of vaccine coverage, different vaccine releasing times and different vaccine deployment methods are incorporated into the HSEIR-V compartmental model. We also design four hybrid vaccination distribution strategies (based on population size, contact pattern matrix, infection rate and infectious risk) for controlling the spread of viral infections. Based on data from the 2009-2010 H1N1 influenza epidemic, we evaluate the effectiveness of our proposed HSEIR-V model and study the effects of different types of human behaviour in responding to epidemics.

Can increasing adult vaccination rates reduce lost time and increase productivity?

PubMed

Rittle, Chad

2014-12-01

This article addresses limited vaccination coverage by providing an overview of the epidemiology of influenza, pertussis, and pneumonia, and the impact these diseases have on work attendance for the worker, the worker's family, and employer profit. Studies focused on the cost of vaccination programs, lost work time, lost employee productivity and acute disease treatment are discussed, as well as strategies for increasing vaccination coverage to reduce overall health care costs for employers. Communicating the benefits of universal vaccination for employees and their families and combating vaccine misinformation among employees are outlined. Copyright 2014, SLACK Incorporated.

The influence of vaccine-critical websites on perceiving vaccination risks.

PubMed

Betsch, Cornelia; Renkewitz, Frank; Betsch, Tilmann; Ulshöfer, Corina

2010-04-01

This large-scale Internet-experiment tests whether vaccine-critical pages raise perceptions of the riskiness of vaccinations and alter vaccination intentions. We manipulated the information environment (vaccine-critical website, control, both) and the focus of search (on vaccination risks, omission risks, no focus). Our analyses reveal that accessing vaccine-critical websites for five to 10 minutes increases the perception of risk of vaccinating and decreases the perception of risk of omitting vaccinations as well as the intentions to vaccinate. In line with the 'risk-as-feelings' approach, the affect elicited by the vaccine-critical websites was positively related to changes in risk perception.

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.

Engineering of Genetically Arrested Parasites (GAPs) For a Precision Malaria Vaccine.

PubMed

Kreutzfeld, Oriana; Müller, Katja; Matuschewski, Kai

2017-01-01

Continuous stage conversion and swift changes in the antigenic repertoire in response to acquired immunity are hallmarks of complex eukaryotic pathogens, including Plasmodium species, the causative agents of malaria. Efficient elimination of Plasmodium liver stages prior to blood infection is one of the most promising malaria vaccine strategies. Here, we describe different genetically arrested parasites (GAPs) that have been engineered in Plasmodium berghei, P. yoelii and P. falciparum and compare their vaccine potential. A better understanding of the immunological mechanisms of prime and boost by arrested sporozoites and experimental strategies to enhance vaccine efficacy by further engineering existing GAPs into a more immunogenic form hold promise for continuous improvements of GAP-based vaccines. A critical hurdle for vaccines that elicit long-lasting protection against malaria, such as GAPs, is safety and efficacy in vulnerable populations. Vaccine research should focus on solutions toward turning malaria into a vaccine-preventable disease, which would offer an exciting new path of malaria control.

The domino effect: adolescent girls' response to human papillomavirus vaccination.

PubMed

Bernard, Diana M; Cooper Robbins, Spring C; McCaffery, Kirsten J; Scott, Caroline M; Skinner, S Rachel

2011-03-21

To examine the experience of fear, the fear response, and factors affecting fear in adolescents undergoing school-based human papillomavirus (HPV) vaccination. A purposive sampling strategy and qualitative methods, including observation and face-to-face interviews. Focus groups comprised adolescent girls who were involved in HPV vaccination in 2007 at schools in Sydney, New South Wales. Individual interviews were conducted with parents, teachers and vaccination nurses. Data from observing vaccination days at three schools and from interviewing 130 adolescents in 20 focus groups, 38 parents, 10 teachers and seven nurses were included in the analysis. All participants discussed the issue of fear and distress experienced by adolescent girls in relation to HPV vaccination. Observations corroborated the focus group and interview data. Our results indicated that fear was promoted by witnessing the fear reactions of peers; perceived judgement by peers; lack of information or misinformation; and being vaccinated later in the day. Fear was moderated by procedural factors, the support of peers, appropriate knowledge, and nurses' distraction techniques or approach. Fear also affected acceptance of HPV vaccination. Fear of HPV vaccination was a near universal experience among adolescents in the school setting and was often associated with significant distress that had an adverse impact on the vaccination process. School vaccination could be improved by proactively managing fear and distress.

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

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.

Vaccinating parents experience vaccine anxiety too.

PubMed

Luthy, Karlen E; Beckstrand, Renea L; Asay, Whitney; Hewett, Carly

2013-12-01

To identify common causes of parental anxiety regarding childhood vaccinations among parents who vaccinate. Another purpose was to seek recommendations for healthcare providers to help parents overcome their anxiety when their children are immunized. Four 1-h focus groups were conducted, each consisting of 8-10 parents. Each focus group discussion was conducted by a moderator and an assistant moderator. The moderator facilitated discussion while the assistant moderator took notes. Each session was recorded on video. The data were transcribed and analyzed for themes. Parents identifying themselves as being compliant with childhood vaccination requirements reported anxiety that can be divided into five major themes: parental anxiety prior to vaccination, parental anxiety during the vaccination, parental anxiety after the vaccination, parental suggestions for healthcare providers, and informational issues. Making minor changes in office policies may help alleviate some parental anxiety regarding vaccinations. Providers should also create lists of credible sources about vaccination information. Because the cause of vaccine-related parental anxiety varies, targeted education is necessary to relieve common causes of vaccine anxiety, even among parents who vaccinate. ©2013 The Author(s) ©2013 American Association of Nurse Practitioners.

Engineering of a hybrid nanoparticle-based nicotine nanovaccine as a next-generation immunotherapeutic strategy against nicotine addiction: A focus on hapten density.

PubMed

Zhao, Zongmin; Powers, Kristen; Hu, Yun; Raleigh, Michael; Pentel, Paul; Zhang, Chenming

2017-04-01

Although vaccination is a promising way to combat nicotine addiction, most traditional hapten-protein conjugate nicotine vaccines only show limited efficacy due to their poor recognition and uptake by immune cells. This study aimed to develop a hybrid nanoparticle-based nicotine vaccine with improved efficacy. The focus was to study the impact of hapten density on the immunological efficacy of the proposed hybrid nanovaccine. It was shown that the nanovaccine nanoparticles were taken up by the dendritic cells more efficiently than the conjugate vaccine, regardless of the hapten density on the nanoparticles. At a similar hapten density, the nanovaccine induced a significantly stronger immune response against nicotine than the conjugate vaccine in mice. Moreover, the high- and medium-density nanovaccines resulted in significantly higher anti-nicotine antibody titers than their low-density counterpart. Specifically, the high-density nanovaccine exhibited better immunogenic efficacy, resulting in higher anti-nicotine antibody titers and lower anti-carrier protein antibody titers than the medium- and low-density versions. The high-density nanovaccine also had the best ability to retain nicotine in serum and to block nicotine from entering the brain. These results suggest that the hybrid nanoparticle-based nicotine vaccine can elicit strong immunogenicity by modulating the hapten density, thereby providing a promising next-generation immunotherapeutic strategy against nicotine addiction. Copyright © 2017 Elsevier Ltd. All rights reserved.

Efficient Vaccine Distribution Based on a Hybrid Compartmental Model

PubMed Central

Yu, Zhiwen; Liu, Jiming; Wang, Xiaowei; Zhu, Xianjun; Wang, Daxing; Han, Guoqiang

2016-01-01

To effectively and efficiently reduce the morbidity and mortality that may be caused by outbreaks of emerging infectious diseases, it is very important for public health agencies to make informed decisions for controlling the spread of the disease. Such decisions must incorporate various kinds of intervention strategies, such as vaccinations, school closures and border restrictions. Recently, researchers have paid increased attention to searching for effective vaccine distribution strategies for reducing the effects of pandemic outbreaks when resources are limited. Most of the existing research work has been focused on how to design an effective age-structured epidemic model and to select a suitable vaccine distribution strategy to prevent the propagation of an infectious virus. Models that evaluate age structure effects are common, but models that additionally evaluate geographical effects are less common. In this paper, we propose a new SEIR (susceptible—exposed—infectious šC recovered) model, named the hybrid SEIR-V model (HSEIR-V), which considers not only the dynamics of infection prevalence in several age-specific host populations, but also seeks to characterize the dynamics by which a virus spreads in various geographic districts. Several vaccination strategies such as different kinds of vaccine coverage, different vaccine releasing times and different vaccine deployment methods are incorporated into the HSEIR-V compartmental model. We also design four hybrid vaccination distribution strategies (based on population size, contact pattern matrix, infection rate and infectious risk) for controlling the spread of viral infections. Based on data from the 2009–2010 H1N1 influenza epidemic, we evaluate the effectiveness of our proposed HSEIR-V model and study the effects of different types of human behaviour in responding to epidemics. PMID:27233015

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.

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

Using hepatitis A and B vaccination as a paradigm for effective HIV vaccine delivery.

PubMed

Rhodes, Scott D; Yee, Leland J

2007-06-01

An understanding of vaccine acceptance and uptake is imperative for successful vaccination of populations that will be primary targets for vaccination after a vaccine against HIV is developed and ready for dissemination. Experiences with vaccination against vaccine-preventable hepatitis (VPH) among men who have sex with men (MSM) may offer key insights to inform future HIV vaccination strategies. The purpose of this analysis was to explore what is known currently about vaccination among MSM, using knowledge gained from vaccination against VPH, and to identify important considerations from these experiences that must be explored further as a vaccine against HIV is promoted among MSM. Because cultural and political differences make it difficult to extrapolate findings from studies in one country to another, we have focused our analyses on studies conducted in the USA. Through a qualitative systematic review of published reports, we identified eight studies that reported correlates of VPH among MSM in the USA. Six major domains of variables associated with vaccination against VPH were identified, including: demographics (e.g. younger age, higher educational attainment); increased vaccine knowledge; increased access to health care; provider recommendation; behaviours (e.g. same-sex behaviour, health-promoting and disease-preventing behaviours); and psychosocial factors (e.g. openness about one's sexual orientation, reduced barriers to being vaccinated, self-efficacy). Further research is needed to understand vaccination behaviour among MSM and to maximise acceptance and uptake after a vaccine exists. Experiences with VPH provide a real-world model on which to base preliminary assumptions about acceptance and uptake of a vaccine against HIV.

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

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

Human Papillomavirus Vaccine Uptake in Adolescent Boys: An Evidence Review.

PubMed

Voss, Danielle S; Wofford, Linda G

2016-10-01

Despite evidence-based guidelines recommending routine vaccination against human papillomavirus (HPV) for adolescent boys, ages 11-12 years, vaccine uptake among this population remains low. To examine reasons for low HPV quadrivalent vaccine uptake and methods available to increase vaccine uptake among adolescent males, ages 11-12 years. Of 341 identified studies, 30 were included from three databases. The 30 studies were grouped into six categories: population-specific, problem-specific, educational interventions, theory-specific, political implications, and foundational guidelines and Websites. Among eight studies, low vaccine uptake was attributed to lack of parental, adolescent, and physician knowledge of HPV4 vaccine availability and recommendations. HPV4 vaccine educational interventions for parents and adolescents were the most effective for promoting vaccine uptake. Theory applications and gain-framed messages were shown to be effective for assessing HPV vaccine attitudes and perceptions. Political implication studies reveal the need for political and financial measures to encourage HPV vaccine acceptability among the population. To promote HPV vaccine uptake among adolescent males, providers must remain current with HPV vaccine recommendations and offer parental and adolescent HPV education focusing on benefits of vaccine acceptance and risks of vaccine refusal. The results of this review inform our understanding of effective educational strategies to positively impact HPV vaccine uptake in adolescent males. Based on this review, clinicians can employ several evidence-based educational strategies to facilitate HPV vaccine uptake. © 2016 Sigma Theta Tau International.

Factors that influence vaccination decision-making by parents who visit an anthroposophical child welfare center: a focus group study.

PubMed

Harmsen, Irene A; Ruiter, Robert A C; Paulussen, Theo G W; Mollema, Liesbeth; Kok, Gerjo; de Melker, Hester E

2012-01-01

In recent years, parents have become more disparaging towards childhood vaccination. One group that is critical about the National Immunization Program (NIP) and participates less comprises parents with an anthroposophical worldview. Despite the fact that various studies have identified anthroposophists as critical parents with lower vaccination coverage, no research has been done to explore the beliefs underlying their childhood vaccination decision-making. We conducted a qualitative study using three focus groups (n = 16) of parents who visit an anthroposophical child welfare center. Our findings show that participants did not refuse all vaccinations within the Dutch NIP, but mostly refused the Mumps, Measles, and Rubella (MMR) vaccination. Vaccination decisions are influenced by participants' lifestyle, perception of health, beliefs about childhood diseases, perceptions about the risks of diseases, perceptions about vaccine effectiveness and vaccine components, and trust in institutions. Parents indicated that they felt a need for more information. Sufficient references should be provided to sources containing more information about childhood vaccination, especially about the effectiveness of vaccines and vaccine components and the risks, such as possible side effects and benefits of vaccination. This may satisfy parents' information needs and enable them to make a sufficiently informed choice whether or not to vaccinate their child.

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

[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.

Recombinant and epitope-based vaccines on the road to the market and implications for vaccine design and production.

PubMed

Oyarzún, Patricio; Kobe, Bostjan

2016-03-03

Novel vaccination approaches based on rational design of B- and T-cell epitopes - epitope-based vaccines - are making progress in the clinical trial pipeline. The epitope-focused recombinant protein-based malaria vaccine (termed RTS,S) is a next-generation approach that successfully reached phase-III trials, and will potentially become the first commercial vaccine against a human parasitic disease. Progress made on methods such as recombinant DNA technology, advanced cell-culture techniques, immunoinformatics and rational design of immunogens are driving the development of these novel concepts. Synthetic recombinant proteins comprising both B- and T-cell epitopes can be efficiently produced through modern biotechnology and bioprocessing methods, and can enable the induction of large repertoires of immune specificities. In particular, the inclusion of appropriate CD4+ T-cell epitopes is increasingly considered a key vaccine component to elicit robust immune responses, as suggested by results coming from HIV-1 clinical trials. In silico strategies for vaccine design are under active development to address genetic variation in pathogens and several broadly protective "universal" influenza and HIV-1 vaccines are currently at different stages of clinical trials. Other methods focus on improving population coverage in target populations by rationally considering specificity and prevalence of the HLA proteins, though a proof-of-concept in humans has not been demonstrated yet. Overall, we expect immunoinformatics and bioprocessing methods to become a central part of the next-generation epitope-based vaccine development and production process.

Influvac, a trivalent inactivated subunit influenza vaccine.

PubMed

Zuccotti, Gian Vincenzo; Fabiano, Valentina

2011-01-01

Influenza represents a major sanitary and socio-economic burden and vaccination is universally considered the most effective strategy for preventing the disease and its complications. Traditional influenza vaccines have been on the market since the late 1940s, with million of doses administered annually worldwide, and demonstrated a substantial efficacy and safety. The trivalent inactivated subunit vaccine has been available for more than 25 years and has been studied in healthy children, adults and the elderly and in people affected by underlying chronic medical conditions. We describe vaccine technology focusing on subunit vaccine production procedures and mode of action and provide updated information on efficacy and safety available data. A review of efficacy and safety data in healthy subjects and in high risk populations from major sponsor- and investigator-driven studies. The vaccine showed a good immunogenicity and a favorable safety profile in all target groups. In the panorama of actually available influenza vaccines, trivalent inactivated subunit vaccine represents a well-established tool for preventing flu and the associated complications.

Prioritization of influenza pandemic vaccination to minimize years of life lost.

PubMed

Miller, Mark A; Viboud, Cecile; Olson, Donald R; Grais, Rebecca F; Rabaa, Maia A; Simonsen, Lone

2008-08-01

How to allocate limited vaccine supplies in the event of an influenza pandemic is currently under debate. Conventional vaccination strategies focus on those at highest risk for severe outcomes, including seniors, but do not consider (1) the signature pandemic pattern in which mortality risk is shifted to younger ages, (2) likely reduced vaccine response in seniors, and (3) differences in remaining years of life with age. We integrated these factors to project the age-specific years of life lost (YLL) and saved in a future pandemic, on the basis of mortality patterns from 3 historical pandemics, age-specific vaccine efficacy, and the 2000 US population structure. For a 1918-like scenario, the absolute mortality risk is highest in people <45 years old; in contrast, seniors (those >or=65 years old) have the highest mortality risk in the 1957 and 1968 scenarios. The greatest YLL savings would be achieved by targeting different age groups in each scenario; people <45 years old in the 1918 scenario, people 45-64 years old in the 1968 scenario, and people >45 years old in the 1957 scenario. Our findings shift the focus of pandemic vaccination strategies onto younger populations and illustrate the need for real-time surveillance of mortality patterns in a future pandemic. Flexible setting of vaccination priority is essential to minimize mortality.

Barriers to and facilitators of child influenza vaccine - perspectives from parents, teens, marketing and healthcare professionals.

PubMed

Bhat-Schelbert, Kavitha; Lin, Chyongchiou Jeng; Matambanadzo, Annamore; Hannibal, Kristin; Nowalk, Mary Patricia; Zimmerman, Richard K

2012-03-23

The CDC recommends annual influenza vaccination for all children age 6 months and older, yet vaccination rates remain modest. Effective strategies to improve influenza vaccination for children are needed. Eight focus groups with 91 parents, teens, pediatric healthcare staff and providers, and immunization and marketing experts were conducted, audiotaped, transcribed verbatim, and coded based on grounded theory. Three themes emerged: barriers, facilitators, and strategies. Barriers included fear, misinformation, and mistrust, with exacerbation of these barriers attributed to media messages. Many considered influenza vaccination unnecessary and inconvenient, but would accept vaccination if recipients or other family members were considered high risk, if recommended by their doctor or another trusted person, or if offered or mandated by the school. Access to better information regarding influenza disease burden and vaccine safety and efficacy were notable facilitators, as were prevention of the inconvenience of missing work or important events, and if the child requests to receive the vaccine. Marketing strategies included incentives, jingles, videos, wearable items, strategically-located information sheets or posters, and promotion by informed counselors. Practice-based strategies included staff buy-in, standing orders protocols, vaccination clinics, and educational videos. Teen-specific strategies included message delivery through schools, texting, internet, and social networking sites. To improve influenza vaccination rates for children using practice-based interventions, participants suggested campaigns that provide better information regarding the vaccine, the disease and its implications, and convenient access to vaccination. Strategies targeting adolescents should use web-based social marketing technologies and campaigns based in schools. Copyright © 2012 Elsevier Ltd. All rights reserved.

Virus-Like Particle, Liposome, and Polymeric Particle-Based Vaccines against HIV-1

PubMed Central

Gao, Yong; Wijewardhana, Chanuka; Mann, Jamie F. S.

2018-01-01

It is acknowledged that vaccines remain the best hope for eliminating the HIV-1 epidemic. However, the failure to produce effective vaccine immunogens and the inability of conventional delivery strategies to elicit the desired immune responses remains a central theme and has ultimately led to a significant roadblock in HIV vaccine development. Consequently, significant efforts have been applied to generate novel vaccine antigens and delivery agents, which mimic viral structures for optimal immune induction. Here, we review the latest developments that have occurred in the nanoparticle vaccine field, with special emphasis on strategies that are being utilized to attain highly immunogenic, systemic, and mucosal anti-HIV humoral and cellular immune responses. This includes the design of novel immunogens, the central role of antigen-presenting cells, delivery routes, and biodistribution of nanoparticles to lymph nodes. In particular, we will focus on virus-like-particle formulations and their preclinical uses within the HIV prophylactic vaccine setting. PMID:29541072

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

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.

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.

Better control with less effort: The advantage of using focused-breathing strategy over focused-distraction strategy on thought suppression.

PubMed

Ju, Yu-Jeng; Lien, Yunn-Wen

2016-02-01

It has been suggested that unwanted thoughts usually intrude during mind wandering due to a shortage of mental resources. However, strategies for suppressing such thoughts have never been examined from a mind wandering perspective. Here, we compare the effectiveness of two types of attention distraction strategies that either redirect users' attention to their own breathing (focused-breathing strategy, FBS) or to a mental image (focused-distraction strategy, FDS) as related to working memory capacities. Eighty-two undergraduates were randomly assigned into a FBS or FDS group. They completed a concentration task and a thought suppression task, in which mind wandering and thought intrusions were each measured. Our results support the hypothesis that mind wandering is positively correlated to thought intrusions and shows that FBS is more effective than FDS in reducing mind wandering and thought intrusions. Moreover, in contrast to FDS, the effect of FBS is independent of users' mental resources. Copyright © 2015 Elsevier Inc. All rights reserved.

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.

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…

Recent advances in vaccine development for herpes simplex virus types I and II.

PubMed

Coleman, Jeffrey L; Shukla, Deepak

2013-04-01

Despite recent advances in vaccine design and strategies, latent infection with herpes simplex virus (HSV) remains a formidable challenge. Approaches involving live-attenuated viruses and inactivated viral preparations were popular throughout the twentieth century. In the past ten years, many vaccine types, both prophylactic or therapeutic, have contained a replication-defective HSV, viral DNA or glycoproteins. New research focused on the mechanism of immune evasion by the virus has involved developing vaccines with various gene deletions and manipulations combined with the use of new and more specific adjuvants. In addition, new "prime-boost" methods of strengthening the vaccine efficacy have proven effective, but there have also been flaws with some recent strategies that appear to have compromised vaccine efficacy in humans. Given the complicated lifecycle of HSV and its unique way of spreading from cell-to-cell, it can be concluded that the development of an ideal vaccine needs new focus on cell-mediated immunity, better understanding of the latent viral genome and serious consideration of gender-based differences in immunity development among humans. This review summarizes recent developments made in the field and sheds light on some potentially new ways to conquer the problem including development of dual-action prophylactic microbicides that prohibit viral entry and, in addition, induce a strong antigen response.

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.

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.

Direct marketing of parenting programs: comparing a promotion-focused and a prevention-focused strategy.

PubMed

Salari, Raziye; Backman, Anna

2017-06-01

: For parenting programs to achieve a public health impact, it is necessary to develop more effective marketing strategies to increase public awareness of these programs and promote parental participation. In this article, we compared a promotion-focused and a prevention-focused strategy via two studies. : We designed two ads inviting parents to participate in a universal parenting program; one ad focused on the program increasing the likelihood of positive outcomes for children (promotion-focused) and the other on the program reducing the likelihood of negative outcomes (prevention-focused). In study I, the two ads were run online simultaneously. Those who clicked on an ad were directed to a website where they could read about and sign up for the program. In study II, a community sample of 706 parents answered a questionnaire about the ads. : In study I, over 85 days, the prevention ad generated more clicks. There was no difference in the number of pages visited on the website nor in the number of parents who signed up for the program. In study II, parents showed a preference for the promotion ad, perceiving it as more relevant and rating it as more effective in getting them interested in the program. : A prevention strategy may be more effective in drawing public attention, in general. However, a promotion strategy is more likely to reach parents, in particular, and inspire them to consider participating in parenting programs. These strategies should be developed further and tested in both general and clinical populations. © The Author 2016. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

The HPV Vaccine: A Comparison of Focus Groups Conducted in South Africa and Ohio Appalachia

PubMed Central

Katz, Mira L.

2013-01-01

Worldwide, cervical cancer is one of the leading causes of morbidity and mortality among women. Even though women in developing countries account for approximately 85 % of the cervical cancer cases and deaths, disparities in cervical cancer rates are also documented in developed countries like the United States (U.S.). Recently, formative research conducted in the U.S. and developing countries like South Africa have sought to gain a better understanding of the knowledge, beliefs, and attitudes about cervical cancer prevention, HPV, and the acceptance of the HPV vaccine. This study compares findings from two independent focus group studies. One study was conducted in a segregated township in Johannesburg, South Africa (n = 24) and the other study was conducted in Ohio Appalachia (n = 19). The following seven themes emerged during the discussions from both studies: HPV and cervical cancer; health decision making; parent–child communication; healthy children; HPV vaccine costs; sexual abuse; and HPV vaccine education. Findings from both studies indicate the importance of the role of mothers and grandmothers in the health care decision-making process for children and a lack of awareness of HPV and its association with cervical cancer. While there was interest in the HPV vaccine, participants voiced concern about the vaccine’s cost and side effects. Some participants expressed concern that receipt of the HPV vaccine may initiate adolescent sexual behavior. However, other participants suggested that the HPV vaccine may protect young women who may experience sexual abuse. The importance of developing culturally appropriate educational materials and programs about cervical cancer prevention and the HPV vaccine were expressed by participants in both countries. PMID:22930347

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

Overview of pertussis: focus on epidemiology, sources of infection, and long term protection after infant vaccination.

PubMed

Edwards, Kathryn M

2005-06-01

Pertussis, or whooping cough, is a bacterial disease characterized by paroxysmal cough often accompanied by inspiratory whoop and posttussive emesis. Although the introduction of whole-cell pertussis vaccine in the 1940s led to a significant decline in the incidence of pertussis, there has been a gradual increase in reported pertussis cases since 1980. Some of these cases are in infants too young to have received routine pertussis vaccination, and many are in adolescents immunized previously as young children. Based on a literature review, an overview of pertussis is provided, focusing on epidemiology, sources of infection, and trends in incidence patterns, particularly among adolescents. Issues surrounding long-term protection after infant vaccination are also discussed. The most dramatic increase in pertussis incidence has been among adolescents and young adults. Waning vaccine-induced immunity and refinements in the diagnosis of pertussis have contributed to the rise in the occurrence of pertussis in older age groups. Disease rates in infants have also increased. Determining the source of infection in infants can be challenging, but studies have demonstrated that many infant cases are attributable to infections in adolescent or adult family members. Pertussis is on the rise, particularly in adolescents. Booster vaccination of adolescents with less-reactogenic acellular pertussis vaccines appears to be the most logical approach to disease prevention in adolescents and reduced transmission to young infants.

What are parents' perspectives on psychological empowerment in the MMR vaccination decision? A focus group study.

PubMed

Fadda, Marta; Galimberti, Elisa; Carraro, Valter; Schulz, Peter J

2016-04-15

Most developed countries do not have compulsory immunisation requirements, but instead issue recommendations. Although parents are expected to make an informed, autonomous (ie, empowered) decision regarding their children's vaccinations, there is no evidence about how parents' interpret this demand nor on the latitude of their decision-making. The goal of this study is to gain insights from parents residing in a low measles-mumps-rubella (MMR) uptake area on what constitutes feelings of empowerment in the decision they have to make on their child's MMR vaccination. A qualitative study employing focus group interviews. 11 vaccination centres and hospitals in the Province of Trento, Italy. 24 mothers and 4 fathers of children for whom the MMR vaccination decision was still pending participated in 6 focus groups. Autonomy and competence were salient themes in relation to empowerment, and were further connected with beliefs regarding legal responsibility and ethics of freedom concerning the decision, parents' relationship with the paediatrician (trust), feelings of relevance of the decision and related stress, and seeking, avoidance, or fear of vaccination-related information. Competence was interpreted as medical knowledge and information-seeking skills, but it was also related to the extent parents perceived the paediatrician to be competent. Since parents' interpretation of empowerment goes beyond mere perceptions of being informed and autonomous and differs across individuals, it is important that this construct be correctly interpreted and implemented by best practice, for instance by explicitly adopting a relational conception of autonomy. Knowing whether parents want to make an empowered decision and what their information and autonomy needs are might help health professionals adapt their communication about immunisation, and promote parental perception of making an informed, autonomous decision. Published by the BMJ Publishing Group Limited. For permission to

What are parents' perspectives on psychological empowerment in the MMR vaccination decision? A focus group study

PubMed Central

Fadda, Marta; Galimberti, Elisa; Carraro, Valter; Schulz, Peter J

2016-01-01

Objectives Most developed countries do not have compulsory immunisation requirements, but instead issue recommendations. Although parents are expected to make an informed, autonomous (ie, empowered) decision regarding their children's vaccinations, there is no evidence about how parents' interpret this demand nor on the latitude of their decision-making. The goal of this study is to gain insights from parents residing in a low measles-mumps-rubella (MMR) uptake area on what constitutes feelings of empowerment in the decision they have to make on their child's MMR vaccination. Design A qualitative study employing focus group interviews. Setting 11 vaccination centres and hospitals in the Province of Trento, Italy. Participants 24 mothers and 4 fathers of children for whom the MMR vaccination decision was still pending participated in 6 focus groups. Results Autonomy and competence were salient themes in relation to empowerment, and were further connected with beliefs regarding legal responsibility and ethics of freedom concerning the decision, parents' relationship with the paediatrician (trust), feelings of relevance of the decision and related stress, and seeking, avoidance, or fear of vaccination-related information. Competence was interpreted as medical knowledge and information-seeking skills, but it was also related to the extent parents perceived the paediatrician to be competent. Conclusions Since parents' interpretation of empowerment goes beyond mere perceptions of being informed and autonomous and differs across individuals, it is important that this construct be correctly interpreted and implemented by best practice, for instance by explicitly adopting a relational conception of autonomy. Knowing whether parents want to make an empowered decision and what their information and autonomy needs are might help health professionals adapt their communication about immunisation, and promote parental perception of making an informed, autonomous decision. PMID

Smallpox: a review of clinical disease and vaccination.

PubMed

Lofquist, Jennifer M; Weimert, Nicole A; Hayney, Mary S

2003-04-15

The clinical course of smallpox infection and the current and future roles of vaccination and strategies for controlling smallpox outbreaks are reviewed. Close personal contact is required for transmission of variola, the DNA virus that causes smallpox. Following an incubation period, infected persons have prodromal symptoms that include high fever, back pain, malaise, and prostration. The eruptive stage is characterized by maculopapular rash that progresses to papules, then vesicles, and then pustules and scab lesions. The mortality rate for smallpox is approximately 30%. Patients having a fever and rash may be confused with having chickenpox. The most effective method for preventing smallpox epidemic progression is vaccination. Until recently, only 15 million doses of smallpox vaccine--manufactured 20 years ago--were available in the United States. The vaccine is a live vaccinia virus preparation administered by scarification with a bifurcated needle. The immune response is protective against orthopoxviruses, including variola. Vaccination is associated with moderate to severe complications, such as generalized vaccinia, eczema vaccinatum, progressive vaccinia, and postvaccinial encephalitis. Efforts for vaccine production are now focused on a live cell-culture-derived vaccinia virus vaccine. Although smallpox was eradicated in 1980, it remains a potential agent for bioterrorism. As a category A biological weapon, its potential to devastate populations causes concern among those in the public health community who have been actively developing plants to deal with smallpox and other potential agents of biological warfare. The only proven effective strategy against smallpox is vaccination.

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.

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.

A kinase-focused compound collection: compilation and screening strategy.

PubMed

Sun, Dongyu; Chuaqui, Claudio; Deng, Zhan; Bowes, Scott; Chin, Donovan; Singh, Juswinder; Cullen, Patrick; Hankins, Gretchen; Lee, Wen-Cherng; Donnelly, Jason; Friedman, Jessica; Josiah, Serene

2006-06-01

Lead identification by high-throughput screening of large compound libraries has been supplemented with virtual screening and focused compound libraries. To complement existing approaches for lead identification at Biogen Idec, a kinase-focused compound collection was designed, developed and validated. Two strategies were adopted to populate the compound collection: a ligand shape-based virtual screening and a receptor-based approach (structural interaction fingerprint). Compounds selected with the two approaches were cherry-picked from an existing high-throughput screening compound library, ordered from suppliers and supplemented with specific medicinal compounds from internal programs. Promising hits and leads have been generated from the kinase-focused compound collection against multiple kinase targets. The principle of the collection design and screening strategy was validated and the use of the kinase-focused compound collection for lead identification has been added to existing strategies.

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

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.

Policy making for vaccine use as a driver of vaccine innovation and development in the developed world.

PubMed

Seib, Katherine; Pollard, Andrew J; de Wals, Philippe; Andrews, Ross M; Zhou, Fangjun; Hatchett, Richard J; Pickering, Larry K; Orenstein, Walter A

2017-03-07

In the past 200years, vaccines have had unmistakable impacts on public health including declines in morbidity and mortality, most markedly in economically-developed countries. Highly engineered vaccines including vaccines for conditions other than infectious diseases are expected to dominate future vaccine development. We examine immunization vaccine policy as a driver of vaccine innovation and development. The pathways to recommendation for use of licensed vaccines in the US, UK, Canada and Australia have been similar, including: expert review of disease epidemiology, disease burden and severity; vaccine immunogenicity, efficacy and safety; programmatic feasibility; public demand; and increasingly cost-effectiveness. Other attributes particularly important in development of future vaccines are likely to include: duration of immunity for improved vaccines such as pertussis; a greater emphasis on optimizing community protection rather than direct protection only; programmatic implementation, feasibility, improvements (as in the case of development of a universal influenza vaccine); public concerns/confidence/fears related to outbreak pathogens like Ebola and Zika virus; and major societal burden for combating hard to treat diseases like HIV and antimicrobial resistant pathogens. Driving innovation and production of future vaccines faces enormous economic hurdles as available approaches, technologies and regulatory pathways become more complex. As such, cost-mitigating strategies and focused, aligned efforts (by governments, private organizations, and private-public partnerships) will likely be needed to continue to spur major advances in vaccine technologies and development. Copyright © 2017 Elsevier Ltd. All rights reserved.

Transport networks and inequities in vaccination: remoteness shapes measles vaccine coverage and prospects for elimination across Africa.

PubMed

Metcalf, C J E; Tatem, A; Bjornstad, O N; Lessler, J; O'Reilly, K; Takahashi, S; Cutts, F; Grenfell, B T

2015-05-01

Measles vaccination is estimated to have averted 13·8 million deaths between 2000 and 2012. Persisting heterogeneity in coverage is a major contributor to continued measles mortality, and a barrier to measles elimination and introduction of rubella-containing vaccine. Our objective is to identify determinants of inequities in coverage, and how vaccine delivery must change to achieve elimination goals, which is a focus of the WHO Decade of Vaccines. We combined estimates of travel time to the nearest urban centre (⩾50 000 people) with vaccination data from Demographic Health Surveys to assess how remoteness affects coverage in 26 African countries. Building on a statistical mapping of coverage against age and geographical isolation, we quantified how modifying the rate and age range of vaccine delivery affects national coverage. Our scenario analysis considers increasing the rate of delivery of routine vaccination, increasing the target age range of routine vaccination, and enhanced delivery to remote areas. Geographical isolation plays a key role in defining vaccine inequity, with greater inequity in countries with lower measles vaccine coverage. Eliminating geographical inequities alone will not achieve thresholds for herd immunity, indicating that changes in delivery rate or age range of routine vaccination will be required. Measles vaccine coverage remains far below targets for herd immunity in many countries on the African continent and is likely to be inadequate for achieving rubella elimination. The impact of strategies such as increasing the upper age range eligible for routine vaccination should be considered.

'It's a logistical nightmare!' Recommendations for optimising human papillomavirus school-based vaccination experience.

PubMed

Robbins, Spring Chenoa Cooper; Bernard, Diana; McCaffery, Kirsten; Skinner, S Rachel

2010-09-01

To date, no published studies examine procedural factors of the school-based human papillomavirus (HPV) vaccination program from the perspective of those involved. This study examines the factors that were perceived to impact optimal vaccination experience. Schools across Sydney were selected to reflect a range of vaccination coverage at the school level and different school types to ensure a range of experiences. Semi-structured focus groups were conducted with girls; and one-on-one interviews were undertaken with parents, teachers and nurses until saturation of data in all emergent themes was reached. Focus groups and interviews explored participants' experiences in school-based HPV vaccination. Transcripts were analysed, letting themes emerge. Themes related to participants' experience of the organisational, logistical and procedural aspects of the vaccination program and their perceptions of an optimal process were organised into two categories: (1) preparation for the vaccination program and (2) vaccination day strategies. In (1), themes emerged regarding commitment to the process from those involved, planning time and space for vaccinations, communication within and between agencies, and flexibility. In (2), themes included vaccinating the most anxious girls first, facilitating peer support, use of distraction techniques, minimising waiting time girls, and support staff. A range of views exists on what constitutes an optimal school-based program. Several findings were identified that should be considered in the development of guidelines for implementing school-based programs. Future research should evaluate how different approaches to acquiring parental consent, and the use of anxiety and fear reduction strategies impact experience and uptake in the school-based setting.

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.

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

Attitudes towards antenatal vaccination, Group B streptococcus and participation in clinical trials: Insights from focus groups and interviews of parents and healthcare professionals.

PubMed

McQuaid, Fiona; Pask, Sophie; Locock, Louise; Davis, Elizabeth; Stevens, Zoe; Plumb, Jane; Snape, Matthew D

2016-07-25

Antenatal vaccination has become a part of routine care during pregnancy in the UK and worldwide, leading to improvements in health for both pregnant women and their infants. However, uptake remains sub-optimal. Other antenatal vaccines targeting major neonatal pathogens, such as Group B streptococcus (GBS), the commonest cause of sepsis and meningitis in the neonatal period, are undergoing clinical trials but more information is needed on how to improve acceptance of such vaccines. Qualitative study using focus groups and interviews; involving 14 pregnant women, 8 mothers with experience of GBS, and 28 maternity healthcare professionals. Questions were asked regarding antenatal vaccines, knowledge of GBS, attitudes to a potential future GBS vaccine and participation in antenatal vaccine trials. All participants were very cautious about vaccination during pregnancy, with harm to the baby being a major concern. Despite this, the pregnant women and parents with experience of GBS were open to the idea of an antenatal GBS vaccine and participating in research, while the maternity professionals were less positive. Major barriers identified included lack of knowledge about GBS and the reluctance of maternity professionals to be involved. In order for a future GBS vaccine to be acceptable to both pregnant women and the healthcare professionals advising them, a major awareness campaign would be required with significant focus on convincing and training maternity professionals. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

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

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.

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.

[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.

Rheumatoid arthritis vaccine therapies: perspectives and lessons from therapeutic ligand epitope antigen presentation system vaccines for models of rheumatoid arthritis

PubMed Central

Rosenthal, Kenneth S.; Mikecz, Katalin; Steiner, Harold L.; Glant, Tibor T.; Finnegan, Alison; Carambula, Roy E.; Zimmerman, Daniel H.

2016-01-01

The current status of therapeutic vaccines for autoimmune diseases is reviewed with rheumatoid arthritis as the focus. Therapeutic vaccines for autoimmune diseases must regulate or subdue responses to common self-antigens. Ideally, such a vaccine would initiate an antigen-specific modulation of the T-cell immune response that drives the inflammatory disease. Appropriate animal models and types of T helper cells and signature cytokine responses that drive autoimmune disease are also discussed. Interpretation of these animal models must be done cautiously because the means of initiation, autoantigens, and even the signature cytokine and T helper cell (Th1 or Th17) responses that are involved in the disease may differ significantly from those in humans. We describe ligand epitope antigen presentation system vaccine modulation of T-cell autoimmune responses as a strategy for the design of therapeutic vaccines for rheumatoid arthritis, which may also be effective in other autoimmune conditions. PMID:25787143

Particle-based vaccines for HIV-1 infection.

PubMed

Young, Kelly R; Ross, Ted M

2003-06-01

The use of live-attenuated viruses as vaccines has been successful for the control of viral infections. However, the development of an effective vaccine against the human immunodeficiency virus (HIV) has proven to be a challenge. HIV infects cells of the immune system and results in a severe immunodeficiency. In addition, the ability of the virus to adapt to immune pressure and the ability to reside in an integrated form in host cells present hurdles for vaccinologists to overcome. A particle-based vaccine strategy has promise for eliciting high titer, long-lived, immune responses to a diverse number of viral epitopes from different HIV antigens. Live-attenuated viruses are effective at generating both cellular and humoral immunity, however, a live-attenuated vaccine for HIV is problematic. The possibility of a live-attenuated vaccine to revert to a pathogenic form or recombine with a wild-type or defective virus in an infected individual is a drawback to this approach. Therefore, these vaccines are currently only being tested in non-human primate models. Live-attenuated vaccines are effective in stimulating immunity, however challenged animals rarely clear viral infection and the degree of attenuation directly correlates with the protection of animals from disease. Another particle-based vaccine approach for HIV involves the use of virus-like particles (VLPs). VLPs mimic the viral particle without causing an immunodeficiency disease. HIV-like particles (HIV-LP) are defined as self-assembling, non-replicating, nonpathogenic, genomeless particles that are similar in size and conformation to intact virions. A variety of VLPs for both HIV and SIV are currently in pre-clinical and clinical trials. This review focuses on the current knowledge regarding the immunogenicity and safety of particle-based vaccine strategies for HIV-1.

Prevention and Control Strategies to Counter Zika Virus, a Special Focus on Intervention Approaches against Vector Mosquitoes—Current Updates

PubMed Central

Singh, Raj K.; Dhama, Kuldeep; Khandia, Rekha; Munjal, Ashok; Karthik, Kumaragurubaran; Tiwari, Ruchi; Chakraborty, Sandip; Malik, Yashpal S.; Bueno-Marí, Rubén

2018-01-01

Zika virus (ZIKV) is the most recent intruder that acquired the status of global threat creating panic and frightening situation to public owing to its rapid spread, attaining higher virulence and causing complex clinical manifestations including microcephaly in newborns and Guillain Barré Syndrome. Alike other flaviviruses, the principal mode of ZIKV transmission is by mosquitoes. Advances in research have provided reliable diagnostics for detecting ZIKV infection, while several drug/therapeutic targets and vaccine candidates have been identified recently. Despite these progresses, currently there is neither any effective drug nor any vaccine available against ZIKV. Under such circumstances and to tackle the problem at large, control measures of which mosquito population control need to be strengthened following appropriate mechanical, chemical, biological and genetic control measures. Apart from this, several other known modes of ZIKV transmission which have gained importance in recent past such as intrauterine, sexual intercourse, and blood-borne spread need to be checked and kept under control by adopting appropriate precautions and utmost care during sexual intercourse, blood transfusion and organ transplantation. The virus inactivation by pasteurization, detergents, chemicals, and filtration can effectively reduce viral load in plasma-derived medicinal products. Added to this, strengthening of the surveillance and monitoring of ZIKV as well as avoiding travel to Zika infected areas would aid in keeping viral infection under check. Here, we discuss the salient advances in the prevention and control strategies to combat ZIKV with a focus on highlighting various intervention approaches against the vector mosquitoes of this viral pathogen along with presenting an overview regarding human intervention measures to counter other modes of ZIKV transmission and spread. Additionally, owing to the success of vaccines for a number of infections globally, a separate

Prevention and Control Strategies to Counter Zika Virus, a Special Focus on Intervention Approaches against Vector Mosquitoes-Current Updates.

PubMed

Singh, Raj K; Dhama, Kuldeep; Khandia, Rekha; Munjal, Ashok; Karthik, Kumaragurubaran; Tiwari, Ruchi; Chakraborty, Sandip; Malik, Yashpal S; Bueno-Marí, Rubén

2018-01-01

Zika virus (ZIKV) is the most recent intruder that acquired the status of global threat creating panic and frightening situation to public owing to its rapid spread, attaining higher virulence and causing complex clinical manifestations including microcephaly in newborns and Guillain Barré Syndrome. Alike other flaviviruses, the principal mode of ZIKV transmission is by mosquitoes. Advances in research have provided reliable diagnostics for detecting ZIKV infection, while several drug/therapeutic targets and vaccine candidates have been identified recently. Despite these progresses, currently there is neither any effective drug nor any vaccine available against ZIKV. Under such circumstances and to tackle the problem at large, control measures of which mosquito population control need to be strengthened following appropriate mechanical, chemical, biological and genetic control measures. Apart from this, several other known modes of ZIKV transmission which have gained importance in recent past such as intrauterine, sexual intercourse, and blood-borne spread need to be checked and kept under control by adopting appropriate precautions and utmost care during sexual intercourse, blood transfusion and organ transplantation. The virus inactivation by pasteurization, detergents, chemicals, and filtration can effectively reduce viral load in plasma-derived medicinal products. Added to this, strengthening of the surveillance and monitoring of ZIKV as well as avoiding travel to Zika infected areas would aid in keeping viral infection under check. Here, we discuss the salient advances in the prevention and control strategies to combat ZIKV with a focus on highlighting various intervention approaches against the vector mosquitoes of this viral pathogen along with presenting an overview regarding human intervention measures to counter other modes of ZIKV transmission and spread. Additionally, owing to the success of vaccines for a number of infections globally, a separate

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.

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.

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

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

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

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/

Will widespread human papillomavirus prophylactic vaccination change sexual practices of adolescent and young adult women in America?

PubMed

Monk, Bradley J; Wiley, Dorothy J

2006-08-01

Two virus-like particle human papillomavirus (HPV) vaccines have been shown to be nearly 100% effective in preventing type-specific persistent HPV infections and associated type-specific high-grade cervical intraepithelial neoplasia (CIN). Recently, it has been hypothesized that the administration of this vaccine to young girls in the United States might increase sexual promiscuity among adolescent women and/or young adults. Thus, it has been suggested that focused vaccine strategies either based on the risk of CIN or gender might be more rational or cost-effective. However, such strategies are unlikely to completely eradicate the burden of this disease and decrease the cost of cervical cancer screening. The suggestion that widespread vaccination will alter sexual practices is refuted and the rationale for the vaccination of all girls and boys is outlined.

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.

Community perceptions of malaria and vaccines in two districts of Mozambique

PubMed Central

2012-01-01

Background Malaria is a leading cause of mortality and morbidity in Mozambique, with nearly three-quarters of the country’s malaria-related deaths occurring in children younger than five years. A malaria vaccine is not yet available, but planning is underway for a possible introduction, as soon as one becomes available. In an effort to inform the planning process, this study explored sociocultural and health communications issues among individuals at the community level who are both responsible for decisions about vaccine use and who are likely to influence decisions about vaccine use. Methods Researchers conducted a qualitative study in two malaria-endemic districts in southern Mozambique. Using criterion-based sampling, they conducted 23 focus group discussions and 26 in-depth interviews. Implementation was guided by the engagement of community stakeholders. Results Community members recognize that malaria contributes to high death rates and affects the workforce, school attendance, and the economy. Vaccines are seen as a means to reduce the threat of childhood illnesses and to keep children and the rest of the community healthy. Perceived constraints to accessing vaccine services include long queues, staff shortages, and a lack of resources at health care facilities. Local leaders play a significant role in motivating caregivers to have their children vaccinated. Participants generally felt that a vaccine could help to prevent malaria, although some voiced concern that the focus was only on young children and not on older children, pregnant women, and the elderly. Probed on their understanding of vaccine efficacy, participants voiced various views, including the perception that while some vaccines did not fully prevent disease they still had important benefits. Overall, it would be essential for local leaders to be involved in the design of specific messages for a future malaria vaccine communications strategy, and for those messages to be translated into

Community perceptions of malaria and vaccines in two districts of Mozambique.

PubMed

Bingham, Allison; Gaspar, Felisbela; Lancaster, Kathryn; Conjera, Juliana; Collymore, Yvette; Ba-Nguz, Antoinette

2012-11-28

Malaria is a leading cause of mortality and morbidity in Mozambique, with nearly three-quarters of the country's malaria-related deaths occurring in children younger than five years. A malaria vaccine is not yet available, but planning is underway for a possible introduction, as soon as one becomes available. In an effort to inform the planning process, this study explored sociocultural and health communications issues among individuals at the community level who are both responsible for decisions about vaccine use and who are likely to influence decisions about vaccine use. Researchers conducted a qualitative study in two malaria-endemic districts in southern Mozambique. Using criterion-based sampling, they conducted 23 focus group discussions and 26 in-depth interviews. Implementation was guided by the engagement of community stakeholders. Community members recognize that malaria contributes to high death rates and affects the workforce, school attendance, and the economy. Vaccines are seen as a means to reduce the threat of childhood illnesses and to keep children and the rest of the community healthy. Perceived constraints to accessing vaccine services include long queues, staff shortages, and a lack of resources at health care facilities. Local leaders play a significant role in motivating caregivers to have their children vaccinated. Participants generally felt that a vaccine could help to prevent malaria, although some voiced concern that the focus was only on young children and not on older children, pregnant women, and the elderly. Probed on their understanding of vaccine efficacy, participants voiced various views, including the perception that while some vaccines did not fully prevent disease they still had important benefits. Overall, it would be essential for local leaders to be involved in the design of specific messages for a future malaria vaccine communications strategy, and for those messages to be translated into local languages. Acceptance of

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

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.

Abeta DNA vaccination for Alzheimer's disease: focus on disease prevention.

PubMed

Cribbs, David H

2010-04-01

several significant advantages, including lower cost and the typical immunization protocol should be much less intrusive to the patient relative to passive therapy, in the advent of Abeta-antibody immune complex-induced adverse events the patients will have to receive immuno-supperssive therapy for an extended period until the anti Abeta antibody levels drop naturally as the effects of the vaccine decays over time. Obviously, improvements in vaccine design are needed to improve both the safety, as well as the efficacy of anti-Abeta immunotherapy. The focus of this review is on the advantages of DNA vaccination for anti-Abeta immunotherapy, and the major hurdles, such as immunosenescence, selection of appropriate molecular adjuvants, universal T cell epitopes, and possibly a polyepitope design based on utilizing existing memory T cells in the general population that were generated in response to childhood or seasonal vaccines, as well as various infections. Ultimately, we believe that the further refinement of our AD DNA epitope vaccines, possibly combined with a prime boost regime will facilitate translation to human clinical trials in either very early AD, or preferably in preclinical stage individuals identified by validated AD biomarkers.

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.

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

Stakeholders' opinions and questions regarding the anticipated malaria vaccine in Tanzania.

PubMed

Mtenga, Sally; Kimweri, Angela; Romore, Idda; Ali, Ali; Exavery, Amon; Sicuri, Elisa; Tanner, Marcel; Abdulla, Salim; Lusingu, John; Kafuruki, Shubi

2016-04-05

Within the context of combined interventions, malaria vaccine may provide additional value in malaria prevention. Stakeholders' perspectives are thus critical for informed recommendation of the vaccine in Tanzania. This paper presents the views of stakeholders with regards to malaria vaccine in 12 Tanzanian districts. Quantitative and qualitative methods were employed. A structured questionnaire was administered to 2123 mothers of under five children. Forty-six in-depth interviews and 12 focus group discussions were conducted with teachers, religious leaders, community health workers, health care professionals, and scientists. Quantitative data analysis involved frequency distributions and cross tabulations using Chi square test to determine the association between malaria vaccine acceptability and independent variables. Qualitative data were analysed thematically. Overall, 84.2% of the mothers had perfect acceptance of malaria vaccine. Acceptance varied significantly according to religion, occupation, tribe and region (p < 0.001). Ninety two percent reported that they will accept the malaria vaccine despite the need to continue using insecticide-treated nets (ITNs), while 88.4% reported that they will accept malaria vaccine even if their children get malaria less often than non-vaccinated children. Qualitative results revealed that the positive opinions towards malaria vaccine were due to a need for additional malaria prevention strategies and expectations that the vaccine will reduce visits to the health facility, deaths, malaria episodes and treatment-related expenses. Vaccine related questions included its side effects, efficacy, protective duration, composition, interaction with other medications, provision schedule, availability to the pregnant women, mode of administration (oral or injection?) and whether a child born of HIV virus or with a chronic illness will be eligible for the vaccine? Stakeholders had high acceptance and positive opinions towards the

Chlamydia vaccine candidates and tools for chlamydial antigen discovery.

PubMed

Rockey, Daniel D; Wang, Jie; Lei, Lei; Zhong, Guangming

2009-10-01

The failure of the inactivated Chlamydia-based vaccine trials in the 1960s has led researchers studying Chlamydia to take cautious and rational approaches to develop safe and effective chlamydial vaccines. Subsequent research efforts focused on three areas. The first is the analysis of the immunobiology of chlamydial infection in animal models, with supporting clinical studies, to identify the immune correlates of both protective immunity and pathological responses. Second, recent radical improvements in genomics, proteomics and associated technologies have assisted in the implementation of creative approaches to search for suitable vaccine candidates. Third, progress in the analysis of host response and adjuvanticity regulating both innate and adaptive immunity at the mucosal site of infection has led to progress in the design of optimal delivery and adjuvant systems for enhancing protective immunity. Considerable progress has been made in the first two areas but research efforts to better define the factors that regulate immunity at mucosal sites of infection and to develop strategies to boost protective immunity via immunomodulation, effective delivery systems and potent adjuvants, have remained elusive. In this article, we will summarize progress in these areas with a focus on chlamydial vaccine antigen discovery, and discuss future directions towards the development of a safe and effective chlamydial vaccine.

Vaccine Policy Issues

DTIC Science & Technology

2005-05-19

evidence “favors rejection” of the idea that either the measles- mumps-rubella vaccine or thimerosal-containing vaccines cause autism (IOM...Immunization Safety Review: Vaccines and Autism , Washington, D.C., National Academies Press, 2004). 46ACIP’s rotavirus vaccine fact sheet is at [http...that the vaccines or preservatives or packaging might cause autism and other neurodevelopmental disorders. One focus has been on thimerosal, a mercury

Sm-p80-Based Schistosomiasis Vaccine: Preparation for Human Clinical Trials.

PubMed

Siddiqui, Afzal A; Siddiqui, Sabrina Z

2017-03-01

Mass antiparasitic drug administration programs and other control strategies have made important contributions in reducing the global prevalence of helminths. Schistosomiasis, however, continues to spread to new geographic areas. The advent of a viable vaccine and its deployment, coupled with existing control efforts, is expected to make significant headway towards sustained schistosomiasis control. In 2016, Science ranked the schistosomiasis vaccine as one of the top 10 vaccines that needs to be urgently developed. A vaccine that is effective against geographically distinct forms of intestinal/hepatic and urinary disease is essential to make a meaningful impact in global reduction of the disease burden. In this opinion article, we focus on salient features of schistosomiasis vaccines in different phases of the clinical development pipeline and highlight the Sm-p80-based vaccine which is now being prepared for human clinical trials. Copyright © 2016 Elsevier Ltd. All rights reserved.

Recent advances in the use of therapeutic cancer vaccines in genitourinary malignancies.

PubMed

Surolia, Ira; Gulley, James; Madan, Ravi A

2014-12-01

Despite a recent increase in US FDA-approved treatments, genitourinary malignancies remain a source of significant morbidity and mortality. One focus of research is the use of therapeutic cancer vaccines in these diseases, and a significant body of clinical trial experience now exists for refining vaccine strategies to enhance antitumor efficacy and develop immune-based combination regimens. In recent years, clinical data from multiple trials in genitourinary malignancies have enhanced our understanding of the potential for immunotherapy in these cancers. There are also emerging clinical strategies that combine cancer vaccines with chemotherapy, radiation, androgen-deprivation therapy and immune checkpoint inhibitors. This review is based on a search of relevant literature for data presented over the past 5 years from clinical trials of cancer vaccines in prostate, bladder and renal carcinomas. In the coming years, clinical trials informed by decades of preclinical data and emerging clinical data will help to define the role of immunotherapy in genitourinary malignancies. Combination strategies that capitalize on the immune properties of standard treatments will bring greater clinical benefits, and immune-based combinations will likely be moved to the neoadjuvant setting, where they may have optimal clinical impact.

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

Prevention and Control Strategies to Counter Dengue Virus Infection.

PubMed

Rather, Irfan A; Parray, Hilal A; Lone, Jameel B; Paek, Woon K; Lim, Jeongheui; Bajpai, Vivek K; Park, Yong-Ha

2017-01-01

Dengue is currently the highest and rapidly spreading vector-borne viral disease, which can lead to mortality in its severe form. The globally endemic dengue poses as a public health and economic challenge that has been attempted to suppress though application of various prevention and control techniques. Therefore, broad spectrum techniques, that are efficient, cost-effective, and environmentally sustainable, are proposed and practiced in dengue-endemic regions. The development of vaccines and immunotherapies have introduced a new dimension for effective dengue control and prevention. Thus, the present study focuses on the preventive and control strategies that are currently employed to counter dengue. While traditional control strategies bring temporary sustainability alone, implementation of novel biotechnological interventions, such as sterile insect technique, paratransgenesis, and production of genetically modified vectors, has improved the efficacy of the traditional strategies. Although a large-scale vector control strategy can be limited, innovative vaccine candidates have provided evidence for promising dengue prevention measures. The use of tetravalent dengue vaccine (CYD-TDV) has been the most effective so far in treating dengue infections. Nonetheless, challenges and limitation hinder the progress of developing integrated intervention methods and vaccines; while the improvement in the latest techniques and vaccine formulation continues, one can hope for a future without the threat of dengue virus.

Prevention and Control Strategies to Counter Dengue Virus Infection

PubMed Central

Rather, Irfan A.; Parray, Hilal A.; Lone, Jameel B.; Paek, Woon K.; Lim, Jeongheui; Bajpai, Vivek K.; Park, Yong-Ha

2017-01-01

Dengue is currently the highest and rapidly spreading vector-borne viral disease, which can lead to mortality in its severe form. The globally endemic dengue poses as a public health and economic challenge that has been attempted to suppress though application of various prevention and control techniques. Therefore, broad spectrum techniques, that are efficient, cost-effective, and environmentally sustainable, are proposed and practiced in dengue-endemic regions. The development of vaccines and immunotherapies have introduced a new dimension for effective dengue control and prevention. Thus, the present study focuses on the preventive and control strategies that are currently employed to counter dengue. While traditional control strategies bring temporary sustainability alone, implementation of novel biotechnological interventions, such as sterile insect technique, paratransgenesis, and production of genetically modified vectors, has improved the efficacy of the traditional strategies. Although a large-scale vector control strategy can be limited, innovative vaccine candidates have provided evidence for promising dengue prevention measures. The use of tetravalent dengue vaccine (CYD-TDV) has been the most effective so far in treating dengue infections. Nonetheless, challenges and limitation hinder the progress of developing integrated intervention methods and vaccines; while the improvement in the latest techniques and vaccine formulation continues, one can hope for a future without the threat of dengue virus. PMID:28791258

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.

Coverage and Influencing Determinants of Influenza Vaccination in Elderly Patients in a Country with a Poor Vaccination Implementation.

PubMed

Ganczak, Maria; Gil, Karolina; Korzeń, Marcin; Bażydło, Marta

2017-06-20

The seasonal influenza vaccination uptake of the elderly in Poland is one of the lowest in Europe. Objective : to assess the vaccination coverage and influencing determinants in patients ≥65 years of age. A cross-sectional study was conducted (November 2015-April 2016) among consecutive patients admitted to a municipal hospital located in the city of Szczecin, North-west Poland. Patients completed researcher-administered, anonymous questionnaires on socio- demographic data/factors related to the vaccination. Results : The response rate: 92.0%. Among 230 patients (79.6% women, median of age 69 years, range 65-89) who agreed to participate, 34.8% (95% Confidence Interval: 28.6-41.0%) were vaccinated. About 15.7% of respondents had not previously heard about the vaccination; 41.3% of those who stated they were vaccinated or planned on being vaccinated the following year, compared to 19.3% of respondents who stated they were not currently vaccinated ( p < 0.001). A multivariable regression analysis revealed that patient factors, such as younger age (Odds Ratio, OR = 7.69), living in the urban area (OR = 7.69), having comorbidities (OR = 2.70), having a vaccinated family member (OR = 3.57), and being informed about vaccination (OR = 5.00) were each associated with greater odds of being immunized. Willingness for vaccination the next year was strongly associated (OR = 8.59) with vaccination status. Conclusions : The influenza vaccination uptake in the elderly population in Poland is disturbingly low. Improved education strategies are needed to increase the uptake. Vaccinated respondents are more likely to plan on being vaccinated the following year. Future interventions related to maximizing vaccination coverage should be more tailored, focusing especially on older patients living in rural areas.

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.

Virus-like particles as a vaccine delivery system: myths and facts.

PubMed

Roy, Polly; Noad, Rob

2009-01-01

Vaccines against viral disease have traditionally relied on attenuated virus strains or inactivation of infectious virus. Subunit vaccines based on viral proteins expressed in heterologous systems have been effective for some pathogens, but have often suffered from poor immunogenicity due to incorrect protein folding or modification. In this chapter we focus on a specific class of viral subunit vaccine that mimics the overall structure of virus particles and thus preserves the native antigenic conformation of the immunogenic proteins. These virus-like particles (VLPs) have been produced for a wide range of taxonomically and structurally distinct viruses, and have unique advantages in terms of safety and immunogenicity over previous approaches. With new VLP vaccines for papillomavirus beginning to reach the market place we argue that this technology has now 'come-of-age' and must be considered a viable vaccine strategy.

Fast vaccine design and development based on correlates of protection (COPs)

PubMed Central

van Els, Cécile; Mjaaland, Siri; Næss, Lisbeth; Sarkadi, Julia; Gonczol, Eva; Smith Korsholm, Karen; Hansen, Jon; de Jonge, Jørgen; Kersten, Gideon; Warner, Jennifer; Semper, Amanda; Kruiswijk, Corine; Oftung, Fredrik

2014-01-01

New and reemerging infectious diseases call for innovative and efficient control strategies of which fast vaccine design and development represent an important element. In emergency situations, when time is limited, identification and use of correlates of protection (COPs) may play a key role as a strategic tool for accelerated vaccine design, testing, and licensure. We propose that general rules for COP-based vaccine design can be extracted from the existing knowledge of protective immune responses against a large spectrum of relevant viral and bacterial pathogens. Herein, we focus on the applicability of this approach by reviewing the established and up-coming COPs for influenza in the context of traditional and a wide array of new vaccine concepts. The lessons learnt from this field may be applied more generally to COP-based accelerated vaccine design for emerging infections. PMID:25424803

Assessing vaccination as a control strategy in an ongoing epidemic: Bovine tuberculosis in African buffalo

USGS Publications Warehouse

Cross, Paul C.; Getz, W.M.

2006-01-01

Bovine tuberculosis (BTB) is an exotic disease invading the buffalo population (Syncerus caffer) of the Kruger National Park (KNP), South Africa. We used a sex and age-structured epidemiological model to assess the effectiveness of a vaccination program and define important research directions. The model allows for dispersal between a focal herd and background population and was parameterized with a combination of published data and analyses of over 130 radio-collared buffalo in the central region of the KNP. Radio-tracking data indicated that all sex and age categories move between mixed herds, and males over 8 years old had higher mortality and dispersal rates than any other sex or age category. In part due to the high dispersal rates of buffalo, sensitivity analyses indicate that disease prevalence in the background population accounts for the most variability in the BTB prevalence and quasi-eradication within the focal herd. Vaccination rate and the transmission coefficient were the second and third most important parameters of the sensitivity analyses. Further analyses of the model without dispersal suggest that the amount of vaccination necessary for quasi-eradication (i.e. prevalence < 5%) depends upon the duration that a vaccine grants protection. Vaccination programs are more efficient (i.e. fewer wasted doses) when they focus on younger individuals. However, even with a lifelong vaccine and a closed population, the model suggests that >70% of the calf population would have to be vaccinated every year to reduce the prevalence to less than 1%. If the half-life of the vaccine is less than 5 years, even vaccinating every calf for 50 years may not eradicate BTB. Thus, although vaccination provides a means of controlling BTB prevalence it should be combined with other control measures if eradication is the objective.

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

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

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

The influence of political ideology and trust on willingness to vaccinate

PubMed Central

Carlisle, Juliet E.; Justwan, Florian

2018-01-01

In light of the increasing refusal of some parents to vaccinate children, public health strategies have focused on increasing knowledge and awareness based on a “knowledge-deficit” approach. However, decisions about vaccination are based on more than mere knowledge of risks, costs, and benefits. Individual decision making about vaccinating involves many other factors including those related to emotion, culture, religion, and socio-political context. In this paper, we use a nationally representative internet survey in the U.S. to investigate socio-political characteristics to assess attitudes about vaccination. In particular, we consider how political ideology and trust affect opinions about vaccinations for flu, pertussis, and measles. Our findings demonstrate that ideology has a direct effect on vaccine attitudes. In particular, conservative respondents are less likely to express pro-vaccination beliefs than other individuals. Furthermore, ideology also has an indirect effect on immunization propensity. The ideology variable predicts an indicator capturing trust in government medical experts, which in turn helps to explain individual-level variation with regards to attitudes about vaccine choice. PMID:29370265

The influence of political ideology and trust on willingness to vaccinate.

PubMed

Baumgaertner, Bert; Carlisle, Juliet E; Justwan, Florian

2018-01-01

In light of the increasing refusal of some parents to vaccinate children, public health strategies have focused on increasing knowledge and awareness based on a "knowledge-deficit" approach. However, decisions about vaccination are based on more than mere knowledge of risks, costs, and benefits. Individual decision making about vaccinating involves many other factors including those related to emotion, culture, religion, and socio-political context. In this paper, we use a nationally representative internet survey in the U.S. to investigate socio-political characteristics to assess attitudes about vaccination. In particular, we consider how political ideology and trust affect opinions about vaccinations for flu, pertussis, and measles. Our findings demonstrate that ideology has a direct effect on vaccine attitudes. In particular, conservative respondents are less likely to express pro-vaccination beliefs than other individuals. Furthermore, ideology also has an indirect effect on immunization propensity. The ideology variable predicts an indicator capturing trust in government medical experts, which in turn helps to explain individual-level variation with regards to attitudes about vaccine choice.

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.

[Do organizational barriers to pneumococcal and influenza vaccine access exist?].

PubMed

Rousseau, Louise; Guay, Maryse; Archambault, Denis; El m'ala, Zahra; Abdelaziz, Nadia

2007-01-01

Despite the implementation of a Quebec immunization program against influenza and pneumococcal disease (PQIIP), vaccine coverage has remained low. There have been many studies on personal barriers to vaccination, but few have explored other kinds of barriers. To explore the presence of barriers in relation to the organization of the health care system and to propose recommendations for increasing vaccine coverage. Within a mixed protocol, a phone survey of 996 people in the target population and a case study implicating the follow-up of the PQIIP with all the site and actor categories via 43 semistructured interviews and 4 focus groups were realized. Survey data underwent a descriptive statistical analysis. Qualitative analysis followed the Miles and Huberman approach. The results indicate the presence of barriers with regard to information accessibility. These include access to: the physicians' recommendation, knowledge of the efficacy or the security of vaccines, and admissibility of clients to the PQIIP. Organizational barriers were also found to limit access to vaccination, especially in terms of restricted choices of time and location. Coordination and incentives mechanisms are not optimal. Removal of organizational barriers depends more on strategic rather than structural factors. Addressing organizational barriers should be an important component of strategies aimed at improving vaccine coverage. Public health authorities should focus on strategic management of the information and inter-organizational environment.

Chimpanzee adenoviral vectors as vaccines for outbreak pathogens

PubMed Central

2017-01-01

ABSTRACT The 2014–15 Ebola outbreak in West Africa highlighted the potential for large disease outbreaks caused by emerging pathogens and has generated considerable focus on preparedness for future epidemics. Here we discuss drivers, strategies and practical considerations for developing vaccines against outbreak pathogens. Chimpanzee adenoviral (ChAd) vectors have been developed as vaccine candidates for multiple infectious diseases and prostate cancer. ChAd vectors are safe and induce antigen-specific cellular and humoral immunity in all age groups, as well as circumventing the problem of pre-existing immunity encountered with human Ad vectors. For these reasons, such viral vectors provide an attractive platform for stockpiling vaccines for emergency deployment in response to a threatened outbreak of an emerging pathogen. Work is already underway to develop vaccines against a number of other outbreak pathogens and we will also review progress on these approaches here, particularly for Lassa fever, Nipah and MERS. PMID:29083948

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.

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.

Vaccinia Virus Vaccines: Past, Present and Future

PubMed Central

Jacobs, Bertram L.; Langland, Jeffrey O.; Kibler, Karen V.; Denzler, Karen L.; White, Stacy D.; Holechek, Susan A.; Wong, Shukmei; Huynh, Trung; Baskin, Carole R.

2009-01-01

Vaccinia virus (VACV) has been used more extensively for human immunization than any other vaccine. For almost two centuries, VACV was employed to provide cross-protection against variola virus, the causative agent of smallpox, until the disease was eradicated in the late 1970s. Since that time, continued research on VACV has produced a number of modified vaccines with improved safety profiles. Attenuation has been achieved through several strategies, including sequential passage in an alternative host, deletion of specific genes or genetic engineering of viral genes encoding immunomodulatory proteins. Some highly attenuated third- and fourth-generation VACV vaccines are now being considered for stockpiling against a possible re-introduction of smallpox through bioterrorism. Researchers have also taken advantage of the ability of the VACV genome to accommodate additional genetic material to produce novel vaccines against a wide variety of infectious agents, including a recombinant VACV encoding the rabies virus glycoprotein that is administered orally to wild animals. This review provides an in-depth examination of these successive generations of VACV vaccines, focusing on how the understanding of poxviral replication and viral gene function permits the deliberate modification of VACV immunogenicity and virulence. PMID:19563829

Collaborative vaccine development: partnering pays.

PubMed

Ramachandra, Rangappa

2008-01-01

Vaccine development, supported by infusions of public and private venture capital, is re-entering a golden age as one of the fastest growing sectors in the life-sciences industry. Demand is driven by great unmet need in underdeveloped countries, increased resistance to current treatments, bioterrorism, and for prevention indications in travelers, pediatric, and adult diseases. Production systems are becoming less reliant on processes such as egg-based manufacturing, while new processes can help to optimize vaccines. Expeditious development hinges on efficient study conduct, which is greatly enhanced through research partnerships with specialized contract research organizations (CROs) that are licensed and knowledgeable in the intricacies of immunology and with the technologic and scientific foundation to support changing timelines and strategies inherent to vaccine development. The CRO often brings a more objective assessment for probability of success and may offer alternative development pathways. Vaccine developers are afforded more flexibility and are free to focus on innovation and internal core competencies. Functions readily outsourced to a competent partner include animal model development, safety and efficacy studies, immunotoxicity and immunogenicity, dose response studies, and stability and potency testing. These functions capitalize on the CRO partner's regulatory and scientific talent and expertise, and reduce infrastructure expenses for the vaccine developer. Successful partnerships result in development efficiencies, elimination or reduced redundancies, and improved time to market. Keys to success include honest communications, transparency, and flexibility.

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.

Live bacterial vaccines--a review and identification of potential hazards.

PubMed

Detmer, Ann; Glenting, Jacob

2006-06-23

The use of live bacteria to induce an immune response to itself or to a carried vaccine component is an attractive vaccine strategy. Advantages of live bacterial vaccines include their mimicry of a natural infection, intrinsic adjuvant properties and their possibility to be administered orally. Derivatives of pathogenic and non-pathogenic food related bacteria are currently being evaluated as live vaccines. However, pathogenic bacteria demands for attenuation to weaken its virulence. The use of bacteria as vaccine delivery vehicles implies construction of recombinant strains that contain the gene cassette encoding the antigen. With the increased knowledge of mucosal immunity and the availability of genetic tools for heterologous gene expression the concept of live vaccine vehicles gains renewed interest. However, administration of live bacterial vaccines poses some risks. In addition, vaccination using recombinant bacteria results in the release of live recombinant organisms into nature. This places these vaccines in the debate on application of genetically modified organisms. In this review we give an overview of live bacterial vaccines on the market and describe the development of new live vaccines with a focus on attenuated bacteria and food-related lactic acid bacteria. Furthermore, we outline the safety concerns and identify the hazards associated with live bacterial vaccines and try to give some suggestions of what to consider during their development.

Community perceptions of malaria and vaccines in the South Coast and Busia regions of Kenya.

PubMed

Ojakaa, David I; Ofware, Peter; Machira, Yvonne W; Yamo, Emmanuel; Collymore, Yvette; Ba-Nguz, Antoinette; Vansadia, Preeti; Bingham, Allison

2011-05-30

Malaria is a leading cause of morbidity and mortality in children younger than 5 years in Kenya. Within the context of planning for a vaccine to be used alongside existing malaria control methods, this study explores sociocultural and health communications issues among individuals who are responsible for or influence decisions on childhood vaccination at the community level. This qualitative study was conducted in two malaria-endemic regions of Kenya--South Coast and Busia. Participant selection was purposive and criterion based. A total of 20 focus group discussions, 22 in-depth interviews, and 18 exit interviews were conducted. Participants understand that malaria is a serious problem that no single tool can defeat. Communities would welcome a malaria vaccine, although they would have questions and concerns about the intervention. While support for local child immunization programs exists, limited understanding about vaccines and what they do is evident among younger and older people, particularly men. Even as health care providers are frustrated when parents do not have their children vaccinated, some parents have concerns about access to and the quality of vaccination services. Some women, including older mothers and those less economically privileged, see themselves as the focus of health workers' negative comments associated with either their parenting choices or their children's appearance. In general, parents and caregivers weigh several factors--such as personal opportunity costs, resource constraints, and perceived benefits--when deciding whether or not to have their children vaccinated, and the decision often is influenced by a network of people, including community leaders and health workers. The study raises issues that should inform a communications strategy and guide policy decisions within Kenya on eventual malaria vaccine introduction. Unlike the current practice, where health education on child welfare and immunization focuses on women, the

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.

[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.

Progress and novel strategies in vaccine development and treatment of anthrax.

PubMed

Chitlaru, Theodor; Altboum, Zeev; Reuveny, Shaul; Shafferman, Avigdor

2011-01-01

The lethal anthrax disease is caused by spores of the gram-positive Bacillus anthracis, a member of the cereus group of bacilli. Although the disease is very rare in the Western world, development of anthrax countermeasures gains increasing attention due to the potential use of B. anthracis spores as a bio-terror weapon. Protective antigen (PA), the non-toxic subunit of the bacterial secreted exotoxin, fulfills the role of recognizing a specific receptor and mediating the entry of the toxin into the host target cells. PA elicits a protective immune response and represents the basis for all current anthrax vaccines. Anti-PA neutralizing antibodies are useful correlates for protection and for vaccine efficacy evaluation. Post exposure anti-toxemic and anti-bacteremic prophylactic treatment of anthrax requires prolonged antibiotic administration. Shorter efficient postexposure treatments may require active or passive immunization, in addition to antibiotics. Although anthrax is acknowledged as a toxinogenic disease, additional factors, other than the bacterial toxin, may be involved in the virulence of B. anthracis and may be needed for the long-lasting protection conferred by PA immunization. The search for such novel factors is the focus of several high throughput genomic and proteomic studies that are already leading to identification of novel targets for therapeutics, for vaccine candidates, as well as biomarkers for detection and diagnosis. © 2010 John Wiley & Sons A/S.

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

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

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.

What maintains parental support for vaccination when challenged by anti-vaccination messages? A qualitative study.

PubMed

Leask, Julie; Chapman, Simon; Hawe, Penelope; Burgess, Margaret

2006-11-30

This study sought to explore how parents respond to competing media messages about vaccine safety. Six focus groups with mothers of infants were shown television vignettes of typical pro- and anti-vaccination claims. Thematic analysis of transcripts was undertaken. Mothers expressed surprise and concern about alleged vaccine risks but quickly reinstated their support for vaccination by deference to authority figures; type-casting immunisation opponents; and notions of anticipatory regret, good parenting and social responsibility. We conclude that personal experiences, value systems and level of trust in health professionals are fundamental to parental decision making about vaccination. Vaccination advocacy should increase the focus on matters of process such as maintaining trust and public confidence, particularly in health professionals. Stories about people affected by vaccine-preventable diseases need to re-enter the public discourse.

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.

Advancing a vaccine to prevent hookworm disease and anemia.

PubMed

Hotez, Peter J; Beaumier, Coreen M; Gillespie, Portia M; Strych, Ulrich; Hayward, Tara; Bottazzi, Maria Elena

2016-06-03

A human hookworm vaccine is under development and in clinical trials in Africa and the Americas. The vaccine contains the Na-APR-1 and Na-GST-1 antigens. It elicits neutralizing antibodies that interfere with establishment of the adult hookworm in the gut and the ability of the parasite to feed on blood. The vaccine target product profile is focused on the immunization of children to prevent hookworm infection and anemia caused by Necator americanus. It is intended for use in low- and middle-income countries where hookworm is highly endemic and responsible for at least three million disability-adjusted life years. So far, the human hookworm vaccine is being developed in the non-profit sector through the Sabin Vaccine Institute Product Development Partnership (PDP), in collaboration with the HOOKVAC consortium of European and African partners. We envision the vaccine to be incorporated into health systems as part of an elimination strategy for hookworm infection and other neglected tropical diseases, and as a means to reduce global poverty and address the Sustainable Development Goals. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

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

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

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

Kicking against the pricks: vaccine sceptics have a different social orientation.

PubMed

Luyten, Jeroen; Desmet, Pieter; Dorgali, Veronica; Hens, Niel; Beutels, Philippe

2014-04-01

In any country, part of the population is sceptical about the utility of vaccination. To develop successful vaccination programmes, it is important to study and understand the defining characteristics of vaccine sceptics. Research till now mainly focused either on the underlying motives of vaccine refusal, or on socio-demographic differences between vaccine sceptics and non-sceptics. It remained till now unexplored whether both groups differ in terms of basic psychological dispositions. We held a population survey in a representative sample of the population in Flanders, Belgium (N = 1050), in which we investigated whether respondents' attitude to vaccination was associated with their basic disposition toward other community members or society in general, as measured by the Triandis and Gelfand social orientation scale. We found that sceptics and non-sceptics have a different social orientation, even when several variables are controlled for. More specifically, vaccine sceptics scored significantly lower on both horizontal individualism and horizontal collectivism, indicating a lower disposition to see others as equals. These findings need confirmation in the context of different countries. Such insights can be valuable to optimize the design of effective communication strategies on vaccination programmes.

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

Hepatitis Vaccines

PubMed Central

Ogholikhan, Sina; Schwarz, Kathleen B.

2016-01-01

Viral hepatitis is a serious health problem all over the world. However, the reduction of the morbidity and mortality due to vaccinations against hepatitis A and hepatitis B has been a major component in the overall reduction in vaccine preventable diseases. We will discuss the epidemiology, vaccine development, and post-vaccination effects of the hepatitis A and B virus. In addition, we discuss attempts to provide hepatitis D vaccine for the 350 million individuals infected with hepatitis B globally. Given the lack of a hepatitis C vaccine, the many challenges facing the production of a hepatitis C vaccine will be shown, along with current and former vaccination trials. As there is no current FDA-approved hepatitis E vaccine, we will present vaccination data that is available in the rest of the world. Finally, we will discuss the existing challenges and questions facing future endeavors for each of the hepatitis viruses, with efforts continuing to focus on dramatically reducing the morbidity and mortality associated with these serious infections of the liver. PMID:26978406

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

Immunotherapeutic Strategies in Breast Cancer: Preclinical and Clinical Trials

DTIC Science & Technology

2007-09-14

Smith, S.K. Loftin, R.A. Krance, M.K. Brenner, and C.M. Rooney, Long-term restoration of immunity against Epstein - Barr virus infection by adoptive...INTRODUCTION This project is focused on the development of novel tumor vaccines directed at MUC1, a transmembrane mucin that is aberrantly expressed in...immunization strategies can be developed to overcome tolerance. Our specific aims are: 1) to assess the effectiveness of vaccine formulations against MUC1

Immunotherapeutic Strategies in Breast Cancer: Preclinical and Clinical Trials

DTIC Science & Technology

2004-09-01

Epstein - Barr virus infection by adoptive transfer of gene-modified virus -specific T lymphocytes. Nat Med 2:551. 52. Mailliard, R. B., S. Egawa, Q. Cai, A...3 DAMID17-01-1-0318 INTRODUCTION This project is focused on the development of novel tumor vaccines directed at MUC1, a transmembrane mucin that is...immunization strategies can be developed to overcome tolerance. Our specific aims are: 1) to assess the effectiveness of vaccine formulations against

Immunotherapeutic Strategies in Breast Cancer: Preclinical and Clinical Trials

DTIC Science & Technology

2008-09-01

submitted. No further follow-up is required. 13.6 If patient is found on central review to be MUC1 negative, the patient will be considered a cancel...vaccine strategy into a phase I clinical trial in patients with undetectable disease following standard therapy . The model of spontaneous mammary...focused on the development of novel tumor vaccines directed at MUC1, a transmembrane mucin that is aberrantly expressed in cancer. MUC1 is expressed on

Immunotherapeutic Strategies in Breast Cancer: Preclinical and Clinical Trials

DTIC Science & Technology

2009-09-01

follow-up is required. 13.6 If patient is found on central review to be MUC1 negative, the patient will be considered a cancel. The Pre...To translate an effective vaccine strategy into a phase I clinical trial in patients with undetectable disease following standard therapy . The model...focused on the development of novel tumor vaccines directed at MUC1, a transmembrane mucin that is aberrantly expressed in cancer. MUC1 is expressed on

Vaccine preventable disease incidence as a complement to vaccine efficacy for setting vaccine policy

PubMed Central

Gessner, Bradford D.; Feikin, Daniel R.

2015-01-01

Traditionally, vaccines have been evaluated in clinical trials that establish vaccine efficacy (VE) against etiology-confirmed disease outcomes, a measure important for licensure. Yet, VE does not reflect a vaccine’s public health impact because it does not account for relative disease incidence. An additional measure that more directly establishes a vaccine’s public health value is the vaccine preventable disease incidence (VPDI), which is the incidence of disease preventable by vaccine in a given context. We describe how VE and VPDI can vary, sometimes in inverse directions, across disease outcomes and vaccinated populations. We provide examples of how VPDI can be used to reveal the relative public health impact of vaccines in developing countries, which can be masked by focus on VE alone. We recommend that VPDI be incorporated along with VE into the analytic plans of vaccine trials, as well as decisions by funders, ministries of health, and regulatory authorities. PMID:24731817

What can HIV vaccine trials teach us about future HIV vaccine dissemination?

PubMed Central

Newman, Peter A.; Duan, Naihua; Kakinami, Lisa; Roberts, Kathleen

2008-01-01

Summary This investigation explored commonalities and differences in barriers and motivators to HIV vaccine trial participation and acceptability of future U.S. Food and Drug Administration (FDA)-approved HIV vaccines in order to identify implications of clinical trials for future HIV vaccine dissemination. Fifteen focus groups were conducted with 157 predominately ethnic minority and low income participants recruited using venue-based sampling in Los Angeles. Data were analyzed using narrative thematic analysis. Barriers and motivators in common across willingness to participate (WTP) in HIV vaccine trials and future HIV vaccine acceptability (e.g., concerns about vaccine-induced infection, false-positives, side effects, efficacy, mistrust and stigma) suggest clinical trials present significant opportunities to develop and evaluate empirically based interventions to support future HIV vaccine dissemination. Barriers specific to HIV vaccine acceptability (e.g., concerns about duration of protection, cross-clade protection, cost and access) also indicate the need for formative research focused specifically on future dissemination. Protection motivation, common to WTP and acceptability, highlights the need to provide and evaluate prevention counseling and education in clinical trials, which may form the basis of evidence-informed preventive interventions to be launched in tandem with dissemination of partial efficacy HIV vaccines. PMID:18420313

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

The current situation of voluntary vaccination and the factors influencing its coverage among children in Takatsuki, Japan: focus on Hib and pneumococcal vaccines.

PubMed

Tsuda, Yuko; Watanabe, Misuzu; Tanimoto, Yoshimi; Hayashida, Itsushi; Kusabiraki, Toshiyuki; Komiyama, Maki; Kono, Koichi

2015-03-01

This study aimed to understand the current scenario of voluntary vaccination and the factors influencing its coverage among 18-month-old children of Takatsuki City, Japan. Based on 1167 parents responses, we found that voluntary vaccination coverage rates were low when compared with routine vaccination rates. The children who were not the first born of the family and who had young and poorly educated parents were less likely to receive voluntary vaccination. Japanese government-supported vaccines, such as Haemophilus influenzae type b and pneumococcal vaccine, had a higher coverage than the vaccines for which parents had to bear the entire vaccination cost. Furthermore, it was found that mass communication media and family pediatricians were effective means to disseminate voluntary vaccination-related information. We envisage that an active participation of medical professionals, easy access to vaccinations, and mass awareness programs will increase voluntary vaccination coverage in Takatsuki. © 2013 APJPH.

Influenza Vaccines: Challenges and Solutions

PubMed Central

Houser, Katherine; Subbarao, Kanta

2015-01-01

Vaccination is the best method for the prevention and control of influenza. Vaccination can reduce illness and lessen severity of infection. This review focuses on how currently licensed influenza vaccines are generated in the U.S., why the biology of influenza poses vaccine challenges, and vaccine approaches on the horizon that address these challenges. PMID:25766291

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.

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.

Vaccination Persuasion Online: A Qualitative Study of Two Provaccine and Two Vaccine-Skeptical Websites

PubMed Central

Hausman, Bernice L; Cashion, Margaret; Lucchesi, Nicholas; Patel, Kelsey; Roberts, Jonathan

2015-01-01

Background Current concerns about vaccination resistance often cite the Internet as a source of vaccine controversy. Most academic studies of vaccine resistance online use quantitative methods to describe misinformation on vaccine-skeptical websites. Findings from these studies are useful for categorizing the generic features of these websites, but they do not provide insights into why these websites successfully persuade their viewers. To date, there have been few attempts to understand, qualitatively, the persuasive features of provaccine or vaccine-skeptical websites. Objective The purpose of this research was to examine the persuasive features of provaccine and vaccine-skeptical websites. The qualitative analysis was conducted to generate hypotheses concerning what features of these websites are persuasive to people seeking information about vaccination and vaccine-related practices. Methods This study employed a fully qualitative case study methodology that used the anthropological method of thick description to detail and carefully review the rhetorical features of 1 provaccine government website, 1 provaccine hospital website, 1 vaccine-skeptical information website focused on general vaccine safety, and 1 vaccine-skeptical website focused on a specific vaccine. The data gathered were organized into 5 domains: website ownership, visual and textual content, user experience, hyperlinking, and social interactivity. Results The study found that the 2 provaccine websites analyzed functioned as encyclopedias of vaccine information. Both of the websites had relatively small digital ecologies because they only linked to government websites or websites that endorsed vaccination and evidence-based medicine. Neither of these websites offered visitors interactive features or made extensive use of the affordances of Web 2.0. The study also found that the 2 vaccine-skeptical websites had larger digital ecologies because they linked to a variety of vaccine-related websites

Vaccination persuasion online: a qualitative study of two provaccine and two vaccine-skeptical websites.

PubMed

Grant, Lenny; Hausman, Bernice L; Cashion, Margaret; Lucchesi, Nicholas; Patel, Kelsey; Roberts, Jonathan

2015-05-29

Current concerns about vaccination resistance often cite the Internet as a source of vaccine controversy. Most academic studies of vaccine resistance online use quantitative methods to describe misinformation on vaccine-skeptical websites. Findings from these studies are useful for categorizing the generic features of these websites, but they do not provide insights into why these websites successfully persuade their viewers. To date, there have been few attempts to understand, qualitatively, the persuasive features of provaccine or vaccine-skeptical websites. The purpose of this research was to examine the persuasive features of provaccine and vaccine-skeptical websites. The qualitative analysis was conducted to generate hypotheses concerning what features of these websites are persuasive to people seeking information about vaccination and vaccine-related practices. This study employed a fully qualitative case study methodology that used the anthropological method of thick description to detail and carefully review the rhetorical features of 1 provaccine government website, 1 provaccine hospital website, 1 vaccine-skeptical information website focused on general vaccine safety, and 1 vaccine-skeptical website focused on a specific vaccine. The data gathered were organized into 5 domains: website ownership, visual and textual content, user experience, hyperlinking, and social interactivity. The study found that the 2 provaccine websites analyzed functioned as encyclopedias of vaccine information. Both of the websites had relatively small digital ecologies because they only linked to government websites or websites that endorsed vaccination and evidence-based medicine. Neither of these websites offered visitors interactive features or made extensive use of the affordances of Web 2.0. The study also found that the 2 vaccine-skeptical websites had larger digital ecologies because they linked to a variety of vaccine-related websites, including government websites. They

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.

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.

Supporting English Language Learners in Social Studies: Language-Focused Strategies

ERIC Educational Resources Information Center

Zhang, Ying

2017-01-01

With the significant enrollment increase of English Language Learners (ELLs) nationwide, social studies teachers face challenges to educate these students. As a response to the literature of preparing all content teachers to work with ELLs, this article introduces three teacher-friendly language-focused strategies. These strategies help social…

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.

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.

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

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.

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.

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

Prevention of bubonic and pneumonic plague using plant-derived vaccines.

PubMed

Alvarez, M Lucrecia; Cardineau, Guy A

2010-01-01

Yersinia pestis, the causative agent of bubonic and pneumonic plague, is an extremely virulent bacterium but there are currently no approved vaccines for protection against this organism. Plants represent an economical and safer alternative to fermentation-based expression systems for the production of therapeutic proteins. The recombinant plague vaccine candidates produced in plants are based on the two most immunogenic antigens of Y. pestis: the fraction-1 capsular antigen (F1) and the low calcium response virulent antigen (V) either in combination or as a fusion protein (F1-V). These antigens have been expressed in plants using all three known possible strategies: nuclear transformation, chloroplast transformation and plant-virus-based expression vectors. These plant-derived plague vaccine candidates were successfully tested in animal models using parenteral, oral, or prime/boost immunization regimens. This review focuses on the recent research accomplishments towards the development of safe and effective pneumonic and bubonic plague vaccines using plants as bioreactors.

Footrot vaccines and vaccination.

PubMed

Dhungyel, Om; Hunter, James; Whittington, Richard

2014-05-30

Research on footrot in small ruminants, which is caused by Dichelobacter nodosus, has led to development of vaccines and their application for control, treatment and eradication of the disease in sheep. Footrot vaccines have evolved over decades to contain monovalent whole cell, multivalent recombinant fimbrial, and finally mono or bivalent recombinant fimbrial antigens. Initially whole cell vaccines made against the few known serogroups of D. nodosus were found to be inefficient in control of the disease in the field, which was attributed to the presence of other unidentified serogroups and also the use of inefficient adjuvants. Fimbriae or pili, which are the basis for antigenic variation, were found to be the major protective and also curative antigens but they are not cross protective between the different serogroups. Multivalent vaccines incorporating all the known serogroups have been proven to be of limited efficacy due to the phenomenon of antigenic competition. Recent studies in Nepal, Bhutan and Australia have shown that outbreak-specific vaccination which involves targeting identified serogroups with mono- or bivalent recombinant fimbrial vaccines, can be very effective in sheep and goats. Where multiple serogroups are present in a flock, antigenic competition can be overcome by sequentially targeting the serogroups with different bivalent vaccines every 3 months. A common antigen which would confer immunity to all serogroups would be the ideal immunogen but the initial studies were not successful in this area. Until universal antigen/s are available, flock specific mono or bivalent fimbrial vaccines are likely to be the most effective tool for control and eradication of footrot in sheep and goats. Future research in footrot vaccines should be focused on improving the duration of prophylaxis by incorporating new and emerging immunomodulators or adjuvants with modified delivery vehicles, discovering a common antigen and understanding the mechanisms of

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

USGS Publications Warehouse