Burden of pediatric influenza A virus infection post swine-flu H1N1 pandemic in Egypt.

PubMed

Khattab, Adel; Shaheen, Malak; Kamel, Terez; El Faramay, Amel; El Rahman, Safaa Abd; Nabil, Dalia; Gouda, Mohamed

2013-09-01

To screen children with influenza like illness or with symptoms of acute respiratory tract infections for influenza A virus infection - post swine flu pandemic era - using rapid influenza diagnostic tests. During two years (2010 & 2011), 1 200 children with influenza like illness or acute respiratory tract infections (according to World Health Organization criteria) were recruited. Their ages ranged from 2-60 months. Nasopharyngeal aspirates specimens were collected from all children for rapid influenza A diagnostic test. Influenza A virus rapid test was positive in 47.5% of the children; the majority (89.6%) were presented with lower respiratory tract infections. Respiratory rate and temperature were significantly higher among positive rapid influenza test patients. Influenza A virus infection is still a major cause of respiratory tract infections in Egyptian children. It should be considered in all cases with cough and febrile episodes and influenza like symptoms even post swine flu pandemic. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Should we fear "flu fear" itself? Effects of H1N1 influenza fear on ED use.

PubMed

McDonnell, William M; Nelson, Douglas S; Schunk, Jeff E

2012-02-01

Surges in patient volumes compromise emergency departments' (EDs') ability to deliver care, as shown by the recent H1N1 influenza (flu) epidemic. Media reports are important in informing the public about health threats, but the effects of media-induced anxiety on ED volumes are unclear. The aim of this study is to examine the effect of widespread public concern about flu on ED use. We reviewed ED data from an integrated health system operating 18 hospital EDs. We compared ED visits during three 1-week periods: (a) a period of heightened public concern regarding flu before the disease was present ("Fear Week"), (b) a subsequent period of active disease ("Flu Week"), and (c) a week before widespread concern ("Control Week"). Fear Week was identified from an analysis of statewide Google electronic searches for "swine flu" and from media announcements about flu. Flu Week was identified from statewide epidemiological data. Data were reviewed from 22 608 visits during the study periods. Fear Week (n = 7712) and Flu Week (n = 7687) were compared to Control Week (n = 7209). Fear Week showed a 7.0% increase in visits (95% confidence interval, 6-8). Pediatric visits increased by 19.7%, whereas adult visits increased by 1%. Flu Week showed an increase over Control Week of 6.6% (95% confidence interval, 6-7). Pediatric visits increased by 10.6%, whereas adult visits increased by 4.8%. At a time of heightened public concern regarding flu but little disease prevalence, EDs experienced substantial increases in patient volumes. These increases were significant and comparable to the increases experienced during the subsequent epidemic of actual disease. Copyright © 2012 Elsevier Inc. All rights reserved.

Pre-infection of pigs with Mycoplasma hyopneumoniae modifies outcomes of infection with European swine influenza virus of H1N1, but not H1N2, subtype.

PubMed

Deblanc, C; Gorin, S; Quéguiner, S; Gautier-Bouchardon, A V; Ferré, S; Amenna, N; Cariolet, R; Simon, G

2012-05-25

Swine influenza virus (SIV) and Mycoplasma hyopneumoniae (Mhp) are widespread in farms and are major pathogens involved in the porcine respiratory disease complex (PRDC). The aim of this experiment was to compare the pathogenicity of European avian-like swine H1N1 and European human-like reassortant swine H1N2 viruses in naïve pigs and in pigs previously infected with Mhp. Six groups of SPF pigs were inoculated intra-tracheally with either Mhp, or H1N1, or H1N2 or Mhp+H1N1 or Mhp+H1N2, both pathogens being inoculated at 21 days intervals in these two last groups. A mock-infected group was included. Although both SIV strains induced clinical signs when singly inoculated, results indicated that the H1N2 SIV was more pathogenic than the H1N1 virus, with an earlier shedding and a greater spread in lungs. Initial infection with Mhp before SIV inoculation increased flu clinical signs and pathogenesis (hyperthermia, loss of appetite, pneumonia lesions) due to the H1N1 virus but did not modify significantly outcomes of H1N2 infection. Thus, Mhp and SIV H1N1 appeared to act synergistically, whereas Mhp and SIV H1N2 would compete, as H1N2 infection led to the elimination of Mhp in lung diaphragmatic lobes. In conclusion, SIV would be a risk factor for the severity of respiratory disorders when associated with Mhp, depending on the viral subtype involved. This experimental model of coinfection with Mhp and avian-like swine H1N1 is a relevant tool for studying the pathogenesis of SIV-associated PRDC and testing intervention strategies for the control of the disease. Copyright © 2012 Elsevier B.V. All rights reserved.

Natural supplements for H1N1 influenza: retrospective observational infodemiology study of information and search activity on the Internet.

PubMed

Hill, Shawndra; Mao, Jun; Ungar, Lyle; Hennessy, Sean; Leonard, Charles E; Holmes, John

2011-05-10

As the incidence of H1N1 increases, the lay public may turn to the Internet for information about natural supplements for prevention and treatment. Our objective was to identify and characterize websites that provide information about herbal and natural supplements with information about H1N1 and to examine trends in the public's behavior in searching for information about supplement use in preventing or treating H1N1. This was a retrospective observational infodemiology study of indexed websites and Internet search activity over the period January 1, 2009, through November 15, 2009. The setting is the Internet as indexed by Google with aggregated Internet user data. The main outcome measures were the frequency of "hits" or webpages containing terms relating to natural supplements co-occurring with H1N1/swine flu, terms relating to natural supplements co-occurring with H1N1/swine flu proportional to all terms relating to natural supplements, webpage rank, webpage entropy, and temporal trend in search activity. A large number of websites support information about supplements and H1N1. The supplement with the highest proportion of H1N1/swine flu information was a homeopathic remedy known as Oscillococcinum that has no known side effects; supplements with the next highest proportions have known side effects and interactions. Webpages with both supplement and H1N1/swine flu information were less likely to be medically curated or authoritative. Search activity for supplements was temporally related to H1N1/swine flu-related news reports and events. The prevalence of nonauthoritative webpages with information about supplements in the context of H1N1/swine flu and the increasing number of searches for these pages suggest that the public is interested in alternatives to traditional prevention and treatment of H1N1. The quality of this information is often questionable and clinicians should be cognizant that patients may be at risk of adverse events associated with the use

The impact of communications about swine flu (influenza A H1N1v) on public responses to the outbreak: results from 36 national telephone surveys in the UK.

PubMed

Rubin, G J; Potts, H W W; Michie, S

2010-07-01

To assess the association between levels of worry about the possibility of catching swine flu and the volume of media reporting about it; the role of psychological factors in predicting likely uptake of the swine flu vaccine; and the role of media coverage and advertising in predicting other swine flu-related behaviours. Data from a series of random-digit-dial telephone surveys were analysed. A time series analysis tested the association between levels of worry and the volume of media reporting on the start day of each survey. Cross-sectional regression analyses assessed the relationships between likely vaccine uptake or behaviour and predictor variables. Thirty-six surveys were run at, on average, weekly intervals across the UK between 1 May 2009 and 10 January 2010. Five surveys (run between 14 August and 13 September) were used to assess likely vaccine uptake. Five surveys (1-17 May) provided data relating to other behaviours. Between 1047 and 1173 people aged 16 years or over took part in each survey: 5175 participants provided data about their likely uptake of the swine flu vaccine; 5419 participants provided data relating to other behaviours. All participants were asked to state how worried they were about the possibility of personally catching swine flu. Subsets were asked how likely they were to take up a swine flu vaccination if offered it and whether they had recently carried tissues with them, bought sanitising hand gel, avoided using public transport or had been to see a general practitioner, visited a hospital or called NHS Direct for a flu-related reason. The percentage of 'very' or 'fairly' worried participants fluctuated between 9.6% and 32.9%. This figure was associated with the volume of media reporting, even after adjusting for the changing severity of the outbreak [chi2(1) = 6.6, p = 0.010, coefficient for log-transformed data = 2.6]. However, this effect only occurred during the UK's first summer wave of swine flu. In total, 56.1% of

Protective efficacy of an inactivated Eurasian avian-like H1N1 swine influenza vaccine against homologous H1N1 and heterologous H1N1 and H1N2 viruses in mice.

PubMed

Sui, Jinyu; Yang, Dawei; Qiao, Chuanling; Xu, Huiyang; Xu, Bangfeng; Wu, Yunpu; Yang, Huanliang; Chen, Yan; Chen, Hualan

2016-07-19

Eurasian avian-like H1N1 (EA H1N1) swine influenza viruses are prevalent in pigs in Europe and Asia, but occasionally cause human infection, which raises concern about their pandemic potential. Here, we produced a whole-virus inactivated vaccine with an EA H1N1 strain (A/swine/Guangxi/18/2011, SW/GX/18/11) and evaluated its efficacy against homologous H1N1 and heterologous H1N1 and H1N2 influenza viruses in mice. A strong humoral immune response, which we measured by hemagglutination inhibition (HI) and virus neutralization (VN), was induced in the vaccine-inoculated mice upon challenge. The inactivated SW/GX/18/11 vaccine provided complete protection against challenge with homologous SW/GX/18/11 virus in mice and provided effective protection against challenge with heterologous H1N1 and H1N2 viruses with distinctive genomic combinations. Our findings suggest that this EA H1N1 vaccine can provide protection against both homologous H1N1 and heterologous H1N1 or H1N2 virus infection. As such, it is an excellent vaccine candidate to prevent H1N1 swine influenza. Copyright © 2016 Elsevier Ltd. All rights reserved.

Identification of swine H1N2/pandemic H1N1 reassortant influenza virus in pigs, United States.

PubMed

Ali, Ahmed; Khatri, Mahesh; Wang, Leyi; Saif, Yehia M; Lee, Chang-Won

2012-07-06

In October and November 2010, novel H1N2 reassortant influenza viruses were identified from pigs showing mild respiratory signs that included cough and depression. Sequence and phylogenetic analysis showed that the novel H1N2 reassortants possesses HA and NA genes derived from recent H1N2 swine isolates similar to those isolated from Midwest. Compared to the majority of reported reassortants, both viruses preserved human-like host restrictive and putative antigenic sites in their HA and NA genes. The four internal genes, PB2, PB1, PA, and NS were similar to the contemporary swine triple reassortant viruses' internal genes (TRIG). Interestingly, NP and M genes of the novel reassortants were derived from the 2009 pandemic H1N1. The NP and M proteins of the two isolates demonstrated one (E16G) and four (G34A, D53E, I109T, and V313I) amino acid changes in the M2 and NP proteins, respectively. Similar amino acid changes were also noticed upon incorporation of the 2009 pandemic H1N1 NP in other reassortant viruses reported in the U.S. Thus the role of those amino acids in relation to host adaptation need to be further investigated. The reassortments of pandemic H1N1 with swine influenza viruses and the potential of interspecies transmission of these reassortants from swine to other species including human indicate the importance of systematic surveillance of swine population to determine the origin, the prevalence of similar reassortants in the U.S. and their impact on both swine production and public health. Copyright © 2012 Elsevier B.V. All rights reserved.

Novel triple-reassortant H1N1 swine influenza viruses in pigs in Tianjin, Northern China.

PubMed

Sun, Ying-Feng; Wang, Xiu-Hui; Li, Xiu-Li; Zhang, Li; Li, Hai-Hua; Lu, Chao; Yang, Chun-Lei; Feng, Jing; Han, Wei; Ren, Wei-Ke; Tian, Xiang-Xue; Tong, Guang-Zhi; Wen, Feng; Li, Ze-Jun; Gong, Xiao-Qian; Liu, Xiao-Min; Ruan, Bao-Yang; Yan, Ming-Hua; Yu, Hai

2016-02-01

Pigs are susceptible to both human and avian influenza viruses and therefore have been proposed to be mixing vessels for the generation of pandemic influenza viruses through reassortment. In this study, for the first time, we report the isolation and genetic analyses of three novel triple-reassortant H1N1 swine influenza viruses from pigs in Tianjin, Northern China. Phylogenetic analysis showed that these novel viruses contained genes from the 2009 pandemic H1N1 (PB2, PB1, PA and NP), Eurasian swine (HA, NA and M) and triple-reassortant swine (NS) lineages. This indicated that the reassortment among the 2009 pandemic H1N1, Eurasian swine and triple-reassortant swine influenza viruses had taken place in pigs in Tianjin and resulted in the generation of new viruses. Furthermore, three human-like H1N1, two classical swine H1N1 and two Eurasian swine H1N1 viruses were also isolated during the swine influenza virus surveillance from 2009 to 2013, which indicated that multiple genetic lineages of swine H1N1 viruses were co-circulating in the swine population in Tianjin, China. The emergence of novel triple-reassortant H1N1 swine influenza viruses may be a potential threat to human health and emphasizes the importance of further continuous surveillance. Copyright © 2015 Elsevier B.V. All rights reserved.

The neuropsychiatric aspects of influenza/swine flu: A selective review

PubMed Central

Manjunatha, Narayana; Math, Suresh Bada; Kulkarni, Girish Baburao; Chaturvedi, Santosh Kumar

2011-01-01

The world witnessed the influenza virus during the seasonal epidemics and pandemics. The current strain of H1N1 (swine flu) pandemic is believed to be the legacy of the influenza pandemic (1918-19). The influenza virus has been implicated in many neuropsychiatric disorders. In view of the recent pandemic, it would be interesting to review the neuropsychiatric aspects of influenza, specifically swine flu. Author used popular search engine ‘PUBMED’ to search for published articles with different MeSH terms using Boolean operator (AND). Among these, a selective review of the published literature was done. Acute manifestations of swine flu varied from behavioral changes, fear of misdiagnosis during outbreak, neurological features like seizures, encephalopathy, encephalitis, transverse myelitis, aseptic meningitis, multiple sclerosis, and Guillian-Barre Syndrome. Among the chronic manifestations, schizophrenia, Parkinson's disease, mood disorder, dementia, and mental retardation have been hypothesized. Further research is required to understand the etiological hypothesis of the chronic manifestations of influenza. The author urges neuroscientists around the world to make use of the current swine flu pandemic as an opportunity for further research. PMID:23271861

The neuropsychiatric aspects of influenza/swine flu: A selective review.

PubMed

Manjunatha, Narayana; Math, Suresh Bada; Kulkarni, Girish Baburao; Chaturvedi, Santosh Kumar

2011-07-01

The world witnessed the influenza virus during the seasonal epidemics and pandemics. The current strain of H1N1 (swine flu) pandemic is believed to be the legacy of the influenza pandemic (1918-19). The influenza virus has been implicated in many neuropsychiatric disorders. In view of the recent pandemic, it would be interesting to review the neuropsychiatric aspects of influenza, specifically swine flu. Author used popular search engine 'PUBMED' to search for published articles with different MeSH terms using Boolean operator (AND). Among these, a selective review of the published literature was done. Acute manifestations of swine flu varied from behavioral changes, fear of misdiagnosis during outbreak, neurological features like seizures, encephalopathy, encephalitis, transverse myelitis, aseptic meningitis, multiple sclerosis, and Guillian-Barre Syndrome. Among the chronic manifestations, schizophrenia, Parkinson's disease, mood disorder, dementia, and mental retardation have been hypothesized. Further research is required to understand the etiological hypothesis of the chronic manifestations of influenza. The author urges neuroscientists around the world to make use of the current swine flu pandemic as an opportunity for further research.

Avian-like A (H1N1) swine influenza virus antibodies among swine farm residents and pigs in southern China.

PubMed

Zhou, Han; Cao, Zhenpeng; Tan, Likai; Fu, Xinliang; Lu, Gang; Qi, Wenbao; Ke, Changwen; Wang, Heng; Sun, Lingshuang; Zhang, Guihong

2014-01-01

Infection of human with avian-like A (H1N1) swine influenza virus (SIV) occasionally occurs in China, suggesting a potential risk of cross-species transmission of the swine influenza H1N1 virus from pigs to humans, particularly to those having direct contact with pigs. A seroepidemiological study was conducted to assess the prevalence of antibodies against the avian-like A (H1N1) SIV among swine farm residents and pigs in southern China to evaluate the risk of infection to swine farm workers. Hemagglutination inhibition (HI) assays revealed that 11.17% (61/546) of the sera samples from swine farm residents in southern China were positive for antibodies against the avian-like A (H1N1) SIV. The difference in numbers of antibody-positive samples obtained from swine farm residents and a control group of healthy city residents was statistically significant (P = 0.031). In addition, 219 of the 1,180 serum samples from pigs were positive for the antibodies against an avian-like A (H1N1) SIV, A/swine/Guangdong/SS1/2013(H1N1), as assessed by HI. The data suggest that occupational exposure of swine farm residents and veterinarians in southern China to pigs may increase their risk of acquiring avian-like A (H1N1) SIV infection. According to a special pig farming model in southern China, the staff and residents are in close contact with infected pigs and may be among the first to become infected.

Experimental infection with H1N1 European swine influenza virus protects pigs from an infection with the 2009 pandemic H1N1 human influenza virus.

PubMed

Busquets, Núria; Segalés, Joaquim; Córdoba, Lorena; Mussá, Tufaria; Crisci, Elisa; Martín-Valls, Gerard E; Simon-Grifé, Meritxell; Pérez-Simó, Marta; Pérez-Maíllo, Monica; Núñez, Jose I; Abad, Francesc X; Fraile, Lorenzo; Pina, Sonia; Majó, Natalia; Bensaid, Albert; Domingo, Mariano; Montoya, María

2010-01-01

The recent pandemic caused by human influenza virus A(H1N1) 2009 contains ancestral gene segments from North American and Eurasian swine lineages as well as from avian and human influenza lineages. The emergence of this A(H1N1) 2009 poses a potential global threat for human health and the fact that it can infect other species, like pigs, favours a possible encounter with other influenza viruses circulating in swine herds. In Europe, H1N1, H1N2 and H3N2 subtypes of swine influenza virus currently have a high prevalence in commercial farms. To better assess the risk posed by the A(H1N1) 2009 in the actual situation of swine farms, we sought to analyze whether a previous infection with a circulating European avian-like swine A/Swine/Spain/53207/2004 (H1N1) influenza virus (hereafter referred to as SwH1N1) generated or not cross-protective immunity against a subsequent infection with the new human pandemic A/Catalonia/63/2009 (H1N1) influenza virus (hereafter referred to as pH1N1) 21 days apart. Pigs infected only with pH1N1 had mild to moderate pathological findings, consisting on broncho-interstitial pneumonia. However, pigs inoculated with SwH1N1 virus and subsequently infected with pH1N1 had very mild lung lesions, apparently attributed to the remaining lesions caused by SwH1N1 infection. These later pigs also exhibited boosted levels of specific antibodies. Finally, animals firstly infected with SwH1N1 virus and latter infected with pH1N1 exhibited undetectable viral RNA load in nasal swabs and lungs after challenge with pH1N1, indicating a cross-protective effect between both strains. © INRA, EDP Sciences, 2010.

Origins of the 2009 H1N1 influenza pandemic in swine in Mexico

PubMed Central

Mena, Ignacio; Nelson, Martha I; Quezada-Monroy, Francisco; Dutta, Jayeeta; Cortes-Fernández, Refugio; Lara-Puente, J Horacio; Castro-Peralta, Felipa; Cunha, Luis F; Trovão, Nídia S; Lozano-Dubernard, Bernardo; Rambaut, Andrew; van Bakel, Harm; García-Sastre, Adolfo

2016-01-01

Asia is considered an important source of influenza A virus (IAV) pandemics, owing to large, diverse viral reservoirs in poultry and swine. However, the zoonotic origins of the 2009 A/H1N1 influenza pandemic virus (pdmH1N1) remain unclear, due to conflicting evidence from swine and humans. There is strong evidence that the first human outbreak of pdmH1N1 occurred in Mexico in early 2009. However, no related swine viruses have been detected in Mexico or any part of the Americas, and to date the most closely related ancestor viruses were identified in Asian swine. Here, we use 58 new whole-genome sequences from IAVs collected in Mexican swine to establish that the swine virus responsible for the 2009 pandemic evolved in central Mexico. This finding highlights how the 2009 pandemic arose from a region not considered a pandemic risk, owing to an expansion of IAV diversity in swine resulting from long-distance live swine trade. DOI: http://dx.doi.org/10.7554/eLife.16777.001 PMID:27350259

Serological Evidence of Pandemic H1N1 Influenza Virus Infections in Greek Swine.

PubMed

Kyriakis, C S; Papatsiros, V G; Athanasiou, L V; Valiakos, G; Brown, I H; Simon, G; Van Reeth, K; Tsiodras, S; Spyrou, V; Billinis, C

2016-08-01

The introduction of the 2009 pandemic H1N1 (pH1N1) influenza virus in pigs changed the epidemiology of influenza A viruses (IAVs) in swine in Europe and the rest of the world. Previously, three IAV subtypes were found in the European pig population: an avian-like H1N1 and two reassortant H1N2 and H3N2 viruses with human-origin haemagglutinin (HA) and neuraminidase proteins and internal genes of avian decent. These viruses pose antigenically distinct HAs, which allow the retrospective diagnosis of infection in serological investigations. However, cross-reactions between the HA of pH1N1 and the HAs of the other circulating H1 IAVs complicate serological diagnosis. The prevalence of IAVs in Greek swine has been poorly investigated. In this study, we examined and compared haemagglutination inhibition (HI) antibody titres against previously established IAVs and pH1N1 in 908 swine sera from 88 herds, collected before and after the 2009 pandemic. While we confirmed the historic presence of the three IAVs established in European swine, we also found that 4% of the pig sera examined after 2009 had HI antibodies only against the pH1N1 virus. Our results indicate that pH1N1 is circulating in Greek pigs and stress out the importance of a vigorous virological surveillance programme. © 2015 Blackwell Verlag GmbH.

Reassortant swine influenza viruses isolated in Japan contain genes from pandemic A(H1N1) 2009.

PubMed

Kanehira, Katsushi; Takemae, Nobuhiro; Uchida, Yuko; Hikono, Hirokazu; Saito, Takehiko

2014-06-01

In 2013, three reassortant swine influenza viruses (SIVs)-two H1N2 and one H3N2-were isolated from symptomatic pigs in Japan; each contained genes from the pandemic A(H1N1) 2009 virus and endemic SIVs. Phylogenetic analysis revealed that the two H1N2 viruses, A/swine/Gunma/1/2013 and A/swine/Ibaraki/1/2013, were reassortants that contain genes from the following three distinct lineages: (i) H1 and nucleoprotein (NP) genes derived from a classical swine H1 HA lineage uniquely circulating among Japanese SIVs; (ii) neuraminidase (NA) genes from human-like H1N2 swine viruses; and (iii) other genes from pandemic A(H1N1) 2009 viruses. The H3N2 virus, A/swine/Miyazaki/2/2013, comprised genes from two sources: (i) hemagglutinin (HA) and NA genes derived from human and human-like H3N2 swine viruses and (ii) other genes from pandemic A(H1N1) 2009 viruses. Phylogenetic analysis also indicated that each of the reassortants may have arisen independently in Japanese pigs. A/swine/Miyazaki/2/2013 were found to have strong antigenic reactivities with antisera generated for some seasonal human-lineage viruses isolated during or before 2003, whereas A/swine/Miyazaki/2/2013 reactivities with antisera against viruses isolated after 2004 were clearly weaker. In addition, antisera against some strains of seasonal human-lineage H1 viruses did not react with either A/swine/Gunma/1/2013 or A/swine/Ibaraki/1/2013. These findings indicate that emergence and spread of these reassortant SIVs is a potential public health risk. © 2014 The Societies and Wiley Publishing Asia Pty Ltd.

Characterization of a newly emerged genetic cluster of H1N1 and H1N2 swine influenza virus in the United States.

PubMed

Vincent, Amy L; Ma, Wenjun; Lager, Kelly M; Gramer, Marie R; Richt, Juergen A; Janke, Bruce H

2009-10-01

H1 influenza A viruses that were distinct from the classical swine H1 lineage were identified in pigs in Canada in 2003–2004; antigenic and genetic characterization identified the hemagglutinin (HA) as human H1 lineage. The viruses identified in Canadian pigs were human lineage in entirety or double (human–swine) reassortants. Here, we report the whole genome sequence analysis of four human-like H1 viruses isolated from U.S. swine in 2005 and 2007. All four isolates were characterized as triple reassortants with an internal gene constellation similar to contemporary U.S. swine influenza virus (SIV), with HA and neuraminidase (NA) most similar to human influenza virus lineages. A 2007 human-like H1N1 was evaluated in a pathogenesis and transmission model and compared to a 2004 reassortant H1N1 SIV isolate with swine lineage HA and NA. The 2007 isolate induced disease typical of influenza virus and was transmitted to contact pigs; however, the kinetics and magnitude differed from the 2004 H1N1 SIV. This study indicates that the human-like H1 SIV can efficiently replicate and transmit in the swine host and now co-circulates with contemporary SIVs as a distinct genetic cluster of H1 SIV.

Two genotypes of H1N2 swine influenza viruses appeared among pigs in China.

PubMed

Xu, Chuantian; Zhu, Qiyun; Yang, Huanliang; Zhang, Xiumei; Qiao, Chuanling; Chen, Yan; Xin, Xiaoguang; Chen, Hualan

2009-10-01

H1N2 is one of the main subtypes of influenza, which circulates in swine all over the world. To investigate the prevalence and genetic of H1N2 in swine of China. Two H1N2 swine influenza viruses were isolated from Tianjin and Guangdong province of China in 2004 and 2006, respectively. The molecular evolution of eight gene segments was analyzed. A/Swine/Tianjin/1/2004 has low identity with A/Swine/Guangdong/2006; in the phylogenetic tree of PA gene, A/Swine/Guangdong/1/2006 and A/Swine/Guangxi/1/2006 along with the H1N2 swine isolates of North America formed a cluster; and A/Swine/Tianjin/2004 and A/Swine/Zhejiang/2004, along with the classical H1N1 swine isolates formed another cluster; except that NA gene of A/Swine/Tianjin/1/2004 fell into the cluster of the H3N2 human influenza virus, indicating the reassortment between H3N2 human and H1N1 swine influenza viruses. Two different genotypes of H1N2 appeared among pigs in China. A/swine/Guangdong/1/06 was probably from H1N2 swine influenza viruses of North America; while A/swine/Tianjin/1/04 maybe come from reassortments of classical H1N1 swine and H3N2 human viruses prevalent in North America.

[Swine-origin influenza H1N1/California--passions and facts].

PubMed

Gendon, Iu Z

2010-01-01

Analysis of pandemic caused by swine influenza virus H1N1/California showed moderate virulence of this virus compared to pandemic viruses, which caused pandemics in 1918, 1957, and 1968. During seasonal influenza epidemic in countries of southern hemisphere (June-August 2009) despite on circulation of H1N1/California strain, epidemics was caused by human influenza viruses H3N2 and H1N1. It was concluded that strain H1N1/California could not be attributed to pandemic strains of influenza viruses.

Structural Basis of Preexisting Immunity to the 2009 H1N1 Pandemic Influenza Virus

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

Xu, Rui; Ekiert, Damian C.; Krause, Jens C.

The 2009 H1N1 swine flu is the first influenza pandemic in decades. The crystal structure of the hemagglutinin from the A/California/04/2009 H1N1 virus shows that its antigenic structure, particularly within the Sa antigenic site, is extremely similar to those of human H1N1 viruses circulating early in the 20th century. The cocrystal structure of the 1918 hemagglutinin with 2D1, an antibody from a survivor of the 1918 Spanish flu that neutralizes both 1918 and 2009 H1N1 viruses, reveals an epitope that is conserved in both pandemic viruses. Thus, antigenic similarity between the 2009 and 1918-like viruses provides an explanation for themore » age-related immunity to the current influenza pandemic.« less

Molecular evolution of H1N1 swine influenza in Guangdong, China, 2016-2017.

PubMed

Cai, Mengkai; Huang, Junming; Bu, Dexin; Yu, Zhiqing; Fu, Xinliang; Ji, Chihai; Zhou, Pei; Zhang, Guihong

2018-06-01

Swine are the main host of the H1N1 swine influenza virus (SIV), however, H1N1 can also infect humans and occasionally cause serious respiratory disease. To trace the evolution of the SIV in Guangdong, China, we performed an epidemic investigation during the period of 2016-2017. Nine H1N1 influenza viruses were isolated from swine nasal swabs. Antigenic analysis revealed that these viruses belonged to two distinct antigenic groups, represented by A/Swine/Guangdong/101/2016 and A/Swine/Guangdong/52/2017. Additionally, three genotypes, known as GD52/17-like, GD493/17-like and GD101/16-like, were identified by phylogenetic analysis. Importantly, the genotypes including a minimum of 4 pdm/09-origin internal genes have become prevalent in China in recent years. A total of 2966 swine serum samples were used to perform hemagglutination inhibition (HI) tests, and the results showed that the seroprevalence values of SW/GD/101/16 (32.2% in 2016, 32.1% in 2017) were significantly higher than the seroprevalence values of SW/GD/52/17 (18.0% in 2016, 16.7% in 2017). Our study showed that the three reassortant genotypes of H1N1 SIV currently circulating in China are stable, but H1N1pdm09 poses challenges to human health by the introduction of internal genes into these reassortant genotypes. Strengthening SIV surveillance is therefore critical for SIV control and minimizing its potential threat to public health. Copyright © 2018 Elsevier B.V. All rights reserved.

Comparative virulence of wild-type H1N1pdm09 influenza A isolates in swine.

PubMed

Henningson, Jamie N; Rajao, Daniela S; Kitikoon, Pravina; Lorusso, Alessio; Culhane, Marie R; Lewis, Nicola S; Anderson, Tavis K; Vincent, Amy L

2015-03-23

In 2009, a novel swine-origin H1N1 (H1N1pdm09) influenza A virus (IAV) reached pandemic status and was soon after detected in pigs worldwide. The objective of this study was to evaluate whether differences in the HA protein can affect pathogenicity and antigenicity of H1N1pdm09 in swine. We compared lung pathology, viral replication and shedding and the antigenic relationships of four wild-type H1N1pdm09 viruses in pigs: one human (CA/09) and three isolated in swine after the pandemic (IL/09, IL/10, and MN/10). The swine strains were selected based upon unique amino acid substitutions in the HA protein. All selected viruses resulted in mild disease and viral shedding through nasal and oral fluids, however, viral replication and the degree of pathology varied between the isolates. A/Swine/IL/5265/2010 (IL/10), with substitutions I120M, S146G, S186P, V252M, had lower viral titers in the lungs and nasal secretions and fewer lung lesions. The other two swine viruses caused respiratory pathology and replicated to titers similar to the human CA/09, although MN/10 (with mutations D45Y, K304E, A425S) had lower nasal shedding. Swine-adapted H1N1pdm09 have zoonotic potential, and have reassorted with other co-circulating swine viruses, influencing the evolution of IAV in swine globally. Further, our results suggest that amino acid changes in the HA gene have the potential to alter the virulence of H1N1pdm09 in swine. Importantly, the limited clinical signs in pigs could result in continued circulation of these viruses with other endemic swine IAVs providing opportunities for reassortment. Published by Elsevier B.V.

Comparative pathology of pigs infected with Korean H1N1, H1N2, or H3N2 swine influenza A viruses.

PubMed

Lyoo, Kwang-Soo; Kim, Jeong-Ki; Jung, Kwonil; Kang, Bo-Kyu; Song, Daesub

2014-09-24

The predominant subtypes of swine influenza A virus (SIV) in Korea swine population are H1N1, H1N2, and H3N2. The viruses are genetically close to the classical U.S. H1N1 and triple-reassortant H1N2 and H3N2 viruses, respectively. Comparative pathogenesis caused by Korean H1N1, H1N2, and H3N2 SIV was evaluated in this study. The H3N2 infected pigs had severe scores of gross and histopathological lesions at post-inoculation days (PID) 2, and this then progressively decreased. Both the H1N1 and H1N2 infected pigs lacked gross lesions at PID 2, but they showed moderate to severe pneumonia on PID 4, 7 and 14. The pigs infected with H1N1 had significant scores of gross and histopathological lesions when compared with the other pigs infected with H1N2, H3N2, and mock at PID 14. Mean SIV antigen-positive scores were rarely detected for pigs infected with H1N2 and H3N2 from PID 7, whereas a significantly increased amount of viral antigens were found in the bronchioles and alveolar epithelium of the H1N1infected pigs at PID 14. We demonstrated that Korean SIV subtypes had different pulmonary pathologic patterns. The Korean H3N2 rapidly induced acute lung lesions such as broncho-interstitial pneumonia, while the Korean H1N1 showed longer course of infection as compared to other strains.

H1N1 influenza viruses varying widely in hemagglutinin stability transmit efficiently from swine to swine and to ferrets.

PubMed

Russier, Marion; Yang, Guohua; Marinova-Petkova, Atanaska; Vogel, Peter; Kaplan, Bryan S; Webby, Richard J; Russell, Charles J

2017-03-01

A pandemic-capable influenza virus requires a hemagglutinin (HA) surface glycoprotein that is immunologically unseen by most people and is capable of supporting replication and transmission in humans. HA stabilization has been linked to 2009 pH1N1 pandemic potential in humans and H5N1 airborne transmissibility in the ferret model. Swine have served as an intermediate host for zoonotic influenza viruses, yet the evolutionary pressure exerted by this host on HA stability was unknown. For over 70 contemporary swine H1 and H3 isolates, we measured HA activation pH to range from pH 5.1 to 5.9 for H1 viruses and pH 5.3 to 5.8 for H3 viruses. Thus, contemporary swine isolates vary widely in HA stability, having values favored by both avian (pH >5.5) and human and ferret (pH ≤5.5) species. Using an early 2009 pandemic H1N1 (pH1N1) virus backbone, we generated three viruses differing by one HA residue that only altered HA stability: WT (pH 5.5), HA1-Y17H (pH 6.0), and HA2-R106K (pH 5.3). All three replicated in pigs and transmitted from pig-to-pig and pig-to-ferret. WT and R106 viruses maintained HA genotype and phenotype after transmission. Y17H (pH 6.0) acquired HA mutations that stabilized the HA protein to pH 5.8 after transmission to pigs and 5.5 after transmission to ferrets. Overall, we found swine support a broad range of HA activation pH for contact transmission and many recent swine H1N1 and H3N2 isolates have stabilized (human-like) HA proteins. This constitutes a heightened pandemic risk and underscores the importance of ongoing surveillance and control efforts for swine viruses.

H1N1 influenza viruses varying widely in hemagglutinin stability transmit efficiently from swine to swine and to ferrets

PubMed Central

Yang, Guohua; Marinova-Petkova, Atanaska; Kaplan, Bryan S.; Webby, Richard J.

2017-01-01

A pandemic-capable influenza virus requires a hemagglutinin (HA) surface glycoprotein that is immunologically unseen by most people and is capable of supporting replication and transmission in humans. HA stabilization has been linked to 2009 pH1N1 pandemic potential in humans and H5N1 airborne transmissibility in the ferret model. Swine have served as an intermediate host for zoonotic influenza viruses, yet the evolutionary pressure exerted by this host on HA stability was unknown. For over 70 contemporary swine H1 and H3 isolates, we measured HA activation pH to range from pH 5.1 to 5.9 for H1 viruses and pH 5.3 to 5.8 for H3 viruses. Thus, contemporary swine isolates vary widely in HA stability, having values favored by both avian (pH >5.5) and human and ferret (pH ≤5.5) species. Using an early 2009 pandemic H1N1 (pH1N1) virus backbone, we generated three viruses differing by one HA residue that only altered HA stability: WT (pH 5.5), HA1-Y17H (pH 6.0), and HA2-R106K (pH 5.3). All three replicated in pigs and transmitted from pig-to-pig and pig-to-ferret. WT and R106 viruses maintained HA genotype and phenotype after transmission. Y17H (pH 6.0) acquired HA mutations that stabilized the HA protein to pH 5.8 after transmission to pigs and 5.5 after transmission to ferrets. Overall, we found swine support a broad range of HA activation pH for contact transmission and many recent swine H1N1 and H3N2 isolates have stabilized (human-like) HA proteins. This constitutes a heightened pandemic risk and underscores the importance of ongoing surveillance and control efforts for swine viruses. PMID:28282440

Pandemic Paradox: Early Life H2N2 Pandemic Influenza Infection Enhanced Susceptibility to Death during the 2009 H1N1 Pandemic.

PubMed

Gagnon, Alain; Acosta, Enrique; Hallman, Stacey; Bourbeau, Robert; Dillon, Lisa Y; Ouellette, Nadine; Earn, David J D; Herring, D Ann; Inwood, Kris; Madrenas, Joaquin; Miller, Matthew S

2018-01-16

Recent outbreaks of H5, H7, and H9 influenza A viruses in humans have served as a vivid reminder of the potentially devastating effects that a novel pandemic could exert on the modern world. Those who have survived infections with influenza viruses in the past have been protected from subsequent antigenically similar pandemics through adaptive immunity. For example, during the 2009 H1N1 "swine flu" pandemic, those exposed to H1N1 viruses that circulated between 1918 and the 1940s were at a decreased risk for mortality as a result of their previous immunity. It is also generally thought that past exposures to antigenically dissimilar strains of influenza virus may also be beneficial due to cross-reactive cellular immunity. However, cohorts born during prior heterosubtypic pandemics have previously experienced elevated risk of death relative to surrounding cohorts of the same population. Indeed, individuals born during the 1890 H3Nx pandemic experienced the highest levels of excess mortality during the 1918 "Spanish flu." Applying Serfling models to monthly mortality and influenza circulation data between October 1997 and July 2014 in the United States and Mexico, we show corresponding peaks in excess mortality during the 2009 H1N1 "swine flu" pandemic and during the resurgent 2013-2014 H1N1 outbreak for those born at the time of the 1957 H2N2 "Asian flu" pandemic. We suggest that the phenomenon observed in 1918 is not unique and points to exposure to pandemic influenza early in life as a risk factor for mortality during subsequent heterosubtypic pandemics. IMPORTANCE The relatively low mortality experienced by older individuals during the 2009 H1N1 influenza virus pandemic has been well documented. However, reported situations in which previous influenza virus exposures have enhanced susceptibility are rare and poorly understood. One such instance occurred in 1918-when those born during the heterosubtypic 1890 H3Nx influenza virus pandemic experienced the highest

Factors Affecting Intention among Students to Be Vaccinated against A/H1N1 Influenza: A Health Belief Model Approach

PubMed Central

Teitler-Regev, Sharon; Shahrabani, Shosh; Benzion, Uri

2011-01-01

The outbreak of A/H1N1 influenza (henceforth, swine flu) in 2009 was characterized mainly by morbidity rates among young people. This study examined the factors affecting the intention to be vaccinated against the swine flu among students in Israel. Questionnaires were distributed in December 2009 among 387 students at higher-education institutions. The research questionnaire included sociodemographic characteristics and Health Belief Model principles. The results show that the factors positively affecting the intention to take the swine flu vaccine were past experience with seasonal flu shot and three HBM categories: higher levels of perceived susceptibility for catching the illness, perceived seriousness of illness, and lower levels of barriers. We conclude that offering the vaccine at workplaces may raise the intention to take the vaccine among young people in Israel. PMID:22229099

Transnational quarantine rhetorics: public mobilization in SARS and in H1N1 flu.

PubMed

Ding, Huiling

2014-06-01

This essay examines how Chinese governments, local communities, and overseas Chinese in North America responded to the perceived health risks of Severe Acute Respiratory Syndrome (SARS) and H1N1 flu through the use of public and participatory rhetoric about risk and quarantines. Focusing on modes of security and quarantine practices, I examine how globalization and the social crises surrounding SARS and H1N1 flu operated to regulate differently certain bodies and areas. I identify three types of quarantines (mandatory, voluntary, and coerced) and conduct a transnational comparative analysis to investigate the relationships among quarantines, rhetoric, and public communication. I argue that health authorities must openly acknowledge the legitimacy of public input and actively seek public support regarding health crises. Only by collaborating with concerned communities and citizens and by providing careful guidance for public participation can health institutions ensure the efficacy of quarantine orders during emerging epidemics.

Comparative virulence of wild-type H1N1pdm09 influenza A isolates in swine

USDA-ARS?s Scientific Manuscript database

In 2009, a novel swine-origin H1N1 (H1N1pdm09) influenza A virus (IAV) reached pandemic status and was soon after detected in pigs worldwide. The objective of this study was to evaluate whether differences in the HA protein can affect pathogenicity and antigenicity of H1N1pdm09 in swine. We compared...

Molecular characterization of a novel reassortant H1N2 influenza virus containing genes from the 2009 pandemic human H1N1 virus in swine from eastern China.

PubMed

Peng, Xiuming; Wu, Haibo; Xu, Lihua; Peng, Xiaorong; Cheng, Linfang; Jin, Changzhong; Xie, Tiansheng; Lu, Xiangyun; Wu, Nanping

2016-06-01

Pandemic outbreaks of H1N1 swine influenza virus have been reported since 2009. Reassortant H1N2 viruses that contain genes from the pandemic H1N1 virus have been isolated in Italy and the United States. However, there is limited information regarding the molecular characteristics of reassortant H1N2 swine influenza viruses in eastern China. Active influenza surveillance programs in Zhejiang Province identified a novel H1N2 influenza virus isolated from pigs displaying clinical signs of influenza virus infection. Whole-genome sequencing was performed and this strain was compared with other influenza viruses available in GenBank. Phylogenetic analysis suggested that the novel strain contained genes from the 2009 pandemic human H1N1 and swine H3N2 viruses. BALB/c mice were infected with the isolated virus to assess its virulence in mice. While the novel H1N2 isolate replicated well in mice, it was found to be less virulent. These results provide additional evidence that swine serve as intermediate hosts or 'mixing vessels' for novel influenza viruses. They also emphasize the importance of surveillance in the swine population for use as an early warning system for influenza outbreaks in swine and human populations.

Modified vaccinia virus Ankara expressing the hemagglutinin of pandemic (H1N1) 2009 virus induces cross-protective immunity against Eurasian 'avian-like' H1N1 swine viruses in mice.

PubMed

Castrucci, Maria R; Facchini, Marzia; Di Mario, Giuseppina; Garulli, Bruno; Sciaraffia, Ester; Meola, Monica; Fabiani, Concetta; De Marco, Maria A; Cordioli, Paolo; Siccardi, Antonio; Kawaoka, Yoshihiro; Donatelli, Isabella

2014-05-01

To examine cross-reactivity between hemagglutinin (HA) derived from A/California/7/09 (CA/09) virus and that derived from representative Eurasian "avian-like" (EA) H1N1 swine viruses isolated in Italy between 1999 and 2008 during virological surveillance in pigs. Modified vaccinia virus Ankara (MVA) expressing the HA gene of CA/09 virus (MVA-HA-CA/09) was used as a vaccine to investigate cross-protective immunity against H1N1 swine viruses in mice. Two classical swine H1N1 (CS) viruses and four representative EA-like H1N1 swine viruses previously isolated during outbreaks of respiratory disease in pigs on farms in Northern Italy were used in this study. Female C57BL/6 mice were vaccinated with MVA/HA/CA/09 and then challenged intranasally with H1N1 swine viruses. Cross-reactive antibody responses were determined by hemagglutination- inhibition (HI) and virus microneutralizing (MN) assays of sera from MVA-vaccinated mice. The extent of protective immunity against infection with H1N1 swine viruses was determined by measuring lung viral load on days 2 and 4 post-challenge. Systemic immunization of mice with CA/09-derived HA, vectored by MVA, elicited cross-protective immunity against recent EA-like swine viruses. This immune protection was related to the levels of cross-reactive HI antibodies in the sera of the immunized mice and was dependent on the similarity of the antigenic site Sa of H1 HAs. Our findings suggest that the herd immunity elicited in humans by the pandemic (H1N1) 2009 virus could limit the transmission of recent EA-like swine HA genes into the influenza A virus gene pool in humans. © 2013 The Authors Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Reassortant H1N1 influenza virus vaccines protect pigs against pandemic H1N1 influenza virus and H1N2 swine influenza virus challenge.

PubMed

Yang, Huanliang; Chen, Yan; Shi, Jianzhong; Guo, Jing; Xin, Xiaoguang; Zhang, Jian; Wang, Dayan; Shu, Yuelong; Qiao, Chuanling; Chen, Hualan

2011-09-28

Influenza A (H1N1) virus has caused human influenza outbreaks in a worldwide pandemic since April 2009. Pigs have been found to be susceptible to this influenza virus under experimental and natural conditions, raising concern about their potential role in the pandemic spread of the virus. In this study, we generated a high-growth reassortant virus (SC/PR8) that contains the hemagglutinin (HA) and neuraminidase (NA) genes from a novel H1N1 isolate, A/Sichuan/1/2009 (SC/09), and six internal genes from A/Puerto Rico/8/34 (PR8) virus, by genetic reassortment. The immunogenicity and protective efficacy of this reassortant virus were evaluated at different doses in a challenge model using a homologous SC/09 or heterologous A/Swine/Guangdong/1/06(H1N2) virus (GD/06). Two doses of SC/PR8 virus vaccine elicited high-titer serum hemagglutination inhibiting (HI) antibodies specific for the 2009 H1N1 virus and conferred complete protection against challenge with either SC/09 or GD/06 virus, with reduced lung lesions and viral shedding in vaccine-inoculated animals compared with non-vaccinated control animals. These results indicated for the first time that a high-growth SC/PR8 reassortant H1N1 virus exhibits properties that are desirable to be a promising vaccine candidate for use in swine in the event of a pandemic H1N1 influenza. Copyright © 2011 Elsevier B.V. All rights reserved.

North American triple reassortant and Eurasian H1N1 swine influenza viruses do not readily reassort to generate a 2009 pandemic H1N1-like virus.

PubMed

Ma, Wenjun; Liu, Qinfang; Qiao, Chuanling; del Real, Gustavo; García-Sastre, Adolfo; Webby, Richard J; Richt, Jürgen A

2014-03-11

The 2009 pandemic H1N1 virus (pH1N1) was derived through reassortment of North American triple reassortant and Eurasian avian-like swine influenza viruses (SIVs). To date, when, how and where the pH1N1 arose is not understood. To investigate viral reassortment, we coinfected cell cultures and a group of pigs with or without preexisting immunity with a Eurasian H1N1 virus, A/Swine/Spain/53207/2004 (SP04), and a North American triple reassortant H1N1 virus, A/Swine/Kansas/77778/2007 (KS07). The infected pigs were cohoused with one or two groups of contact animals to investigate viral transmission. In coinfected MDCK or PK15 continuous cell lines with KS07 and SP04 viruses, more than 20 different reassortant viruses were found. In pigs without or with preexisting immunity (immunized with commercial inactivated swine influenza vaccines) and coinfected with both viruses, six or seven reassortant viruses, as well as the parental viruses, were identified in bronchoalveolar lavage fluid samples from the lungs. Interestingly, only one or two viruses transmitted to and were detected in contact animals. No reassortant containing a gene constellation similar to that of pH1N1 virus was found in either coinfected cells or pigs, indicating that the reassortment event that resulted in the generation of this virus is a rare event that likely involved specific viral strains and/or a favorable, not-yet-understood environment. IMPORTANCE The 2009 pandemic-like H1N1 virus could not be reproduced either in cell cultures or in pigs coinfected with North American triple reassortant H1N1 and Eurasian H1N1 swine influenza viruses. This finding suggests that the generation of the 2009 pandemic H1N1 virus by reassortment was a rare event that likely involved specific viral strains and unknown factors. Different reassortant viruses were detected in coinfected pigs with and without preexisting immunity, indicating that host immunity plays a relevant role in driving viral reassortment of

'By failing to prepare you are preparing to fail': lessons from the 2009 H1N1 'swine flu' pandemic.

PubMed

Crosier, Adam; McVey, Dominic; French, Jeff

2015-02-01

Pandemic influenza has the potential to cause widespread death and destruction. Communications with the public have a vital role in the prevention of pandemic influenza by promoting the effective uptake of behaviours that can delay the spread of infection. This study explored the development and implementation of communications in the pandemic influenza outbreak of H1N1 ('swine flu') in 2009 in three European countries. In-depth interviews were conducted with senior policy and communication officials involved in the planning and delivery of communications programmes in England, Italy and Hungary. The study found a lack of planning and a low value attached to the skills required to produce effective communications. In all case study countries there was a dearth of good quality audience research to inform the development of communications. Little thought had been given to the tone, targeting or channelling of messages. Instead, communications were characterized by a 'one size fits all' and a 'top down', expert-led response. There was also little effort to evaluate the impact of communications, but where this was done, very low levels of public compliance and engagement with key behavioural messages were found. Policy makers should prioritize investment in the skills and expertise required to achieve desired behaviour changes. Audience research should be conducted throughout the planning cycle to inform national communications strategies. This should include insights to inform the segmentation of public audiences, targeting of messages and consideration of content and emotional tone most likely to achieve desired behavioural outcomes. © The Author 2014. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Genomic reassortants of pandemic A (H1N1) 2009 virus and endemic porcine H1 and H3 viruses in swine in Japan.

PubMed

Kirisawa, Rikio; Ogasawara, Yoshitaka; Yoshitake, Hayato; Koda, Asuka; Furuya, Tokujiro

2014-11-01

From 2010 to 2013 in Japan, we isolated 11 swine influenza viruses (SIVs) from pigs showing respiratory symptoms. Sequence and phylogenetic analyses showed that 6 H1N1 viruses originated from the pandemic (H1N1) 2009 (pdm 09) virus and the other 5 viruses were reassortants between SIVs and pdm 09 viruses, representing 4 genotypes. Two H1N2 viruses contained H1 and N2 genes originated from Japanese H1N2 SIV together with internal genes of pdm 09 viruses. Additionally, 1 H1N2 virus contained a further NP gene originating from Japanese H1N2 SIV. One H1N1 virus contained only the H1 gene originating from Japanese H1 SIV in a pdm 09 virus background. One H3N2 virus contained H3 and N2 genes originating from Japanese H3N2 SIV together with internal genes of pdm 09 virus. The results indicate that pdm 09 viruses are distributed widely in the Japanese swine population and that several reassortments with Japanese SIVs have occurred.

Is it a policy crisis or it is a health crisis? The Egyptian context--analysis of the Egyptian health policy for the H1N1 flu pandemic control.

PubMed

Seef, Sameh; Jeppsson, Anders

2013-01-01

A new influenza virus that was first detected in people in April 2009, was initially referred to colloquially as "swine flu", since it contained genes from swine, avian and human influenza viruses. It can, however, not be transmitted by eating pork or dealing with pigs. In Egypt, several hundred thousand pigs were killed in May, in spite of advice from global health authorities that such an action was unnecessary. Pigs are raised and consumed mainly by the Christian minority, which constitute some 10% of the population. Health Ministry estimated there were between 300,000-350,000 pigs in Egypt. This paper will analyze the Egyptian health policy for controlling the pandemic H1N1 flu, exploring its context, content, process, and actors. The analysis is based on the Leichter Context, which refers to systemic factors-political, economic and social, both national and international-that may have an effect on health policy, and is based on data collected from literature review and policy documents. The International health officials said the swine flu virus that has caused worldwide fear is not transmitted by pigs, and that pig slaughters do nothing to stop its spread. The WHO stopped using the term "swine flu" to avoid confusion. In Egypt, even the editor of a pro-government newspaper criticized the order to slaughter: "Killing (pigs) is not a solution, otherwise, we should kill the people, because the virus spreads through them," wrote Abdullah Kamal of the daily Rose El-Youssef. The World Health organization also criticized the decision. The extinction of the Egyptian pigs is an example of how a health issue can be used to persecute a minority within a country. Although the current influenza has nothing whatsoever to do with pigs, the previous name of the epidemic was used as an argument to violate the rights of the Christian minority in Egypt.

Efficacy of a high-growth reassortant H1N1 influenza virus vaccine against the classical swine H1N1 subtype influenza virus in mice and pigs.

PubMed

Wen, Feng; Yu, Hai; Yang, Fu-Ru; Huang, Meng; Yang, Sheng; Zhou, Yan-Jun; Li, Ze-Jun; Tong, Guang-Zhi

2014-11-01

Swine influenza (SI) is an acute, highly contagious respiratory disease caused by swine influenza A viruses (SwIVs), and it poses a potential global threat to human health. Classical H1N1 (cH1N1) SwIVs are still circulating and remain the predominant subtype in the swine population in China. In this study, a high-growth reassortant virus (GD/PR8) harboring the hemagglutinin (HA) and neuraminidase (NA) genes from a novel cH1N1 isolate in China, A/Swine/Guangdong/1/2011 (GD/11) and six internal genes from the high-growth A/Puerto Rico/8/34(PR8) virus was generated by plasmid-based reverse genetics and tested as a candidate seed virus for the preparation of an inactivated vaccine. The protective efficacy of this vaccine was evaluated in mice and pigs challenged with GD/11 virus. Prime and boost inoculation of GD/PR8 vaccine yielded high-titer serum hemagglutination inhibiting (HI) antibodies and IgG antibodies for GD/11 in both mice and pigs. Complete protection of mice and pigs against cH1N1 SIV challenge was observed, with significantly fewer lung lesions and reduced viral shedding in vaccine-inoculated animals compared with unvaccinated control animals. Our data demonstrated that the GD/PR8 may serve as the seed virus for a promising SwIVs vaccine to protect the swine population.

Antigenic variation of H1N1, H1N2 and H3N2 swine influenza viruses in Japan and Vietnam.

PubMed

Takemae, Nobuhiro; Nguyen, Tung; Ngo, Long Thanh; Hiromoto, Yasuaki; Uchida, Yuko; Pham, Vu Phong; Kageyama, Tsutomu; Kasuo, Shizuko; Shimada, Shinichi; Yamashita, Yasutaka; Goto, Kaoru; Kubo, Hideyuki; Le, Vu Tri; Van Vo, Hung; Do, Hoa Thi; Nguyen, Dang Hoang; Hayashi, Tsuyoshi; Matsuu, Aya; Saito, Takehiko

2013-04-01

The antigenicity of the influenza A virus hemagglutinin is responsible for vaccine efficacy in protecting pigs against swine influenza virus (SIV) infection. However, the antigenicity of SIV strains currently circulating in Japan and Vietnam has not been well characterized. We examined the antigenicity of classical H1 SIVs, pandemic A(H1N1)2009 (A(H1N1)pdm09) viruses, and seasonal human-lineage SIVs isolated in Japan and Vietnam. A hemagglutination inhibition (HI) assay was used to determine antigenic differences that differentiate the recent Japanese H1N2 and H3N2 SIVs from the H1N1 and H3N2 domestic vaccine strains. Minor antigenic variation between pig A(H1N1)pdm09 viruses was evident by HI assay using 13 mAbs raised against homologous virus. A Vietnamese H1N2 SIV, whose H1 gene originated from a human strain in the mid-2000s, reacted poorly with post-infection ferret serum against human vaccine strains from 2000-2010. These results provide useful information for selection of optimal strains for SIV vaccine production.

Continual Reintroduction of Human Pandemic H1N1 Influenza A Viruses into Swine in the United States, 2009 to 2014

PubMed Central

Stratton, Jered; Killian, Mary Lea; Janas-Martindale, Alicia; Vincent, Amy L.

2015-01-01

ABSTRACT The diversity of influenza A viruses in swine (swIAVs) presents an important pandemic threat. Knowledge of the human-swine interface is particularly important for understanding how viruses with pandemic potential evolve in swine hosts. Through phylogenetic analysis of contemporary swIAVs in the United States, we demonstrate that human-to-swine transmission of pandemic H1N1 (pH1N1) viruses has occurred continuously in the years following the 2009 H1N1 pandemic and has been an important contributor to the genetic diversity of U.S. swIAVs. Although pandemic H1 and N1 segments had been largely removed from the U.S. swine population by 2013 via reassortment with other swIAVs, these antigens reemerged following multiple human-to-swine transmission events during the 2013-2014 seasonal epidemic. These findings indicate that the six internal gene segments from pH1N1 viruses are likely to be sustained long term in the U.S. swine population, with periodic reemergence of pandemic hemagglutinin (HA) and neuraminidase (NA) segments in association with seasonal pH1N1 epidemics in humans. Vaccinating U.S. swine workers may reduce infection of both humans and swine and in turn limit the role of humans as sources of influenza virus diversity in pigs. IMPORTANCE Swine are important hosts in the evolution of influenza A viruses with pandemic potential. Here, we analyze influenza virus sequence data generated by the U.S. Department of Agriculture's national surveillance system to identify the central role of humans in the reemergence of pandemic H1N1 (pH1N1) influenza viruses in U.S. swine herds in 2014. These findings emphasize the important role of humans as continuous sources of influenza virus diversity in swine and indicate that influenza viruses with pandemic HA and NA segments are likely to continue to reemerge in U.S. swine in association with seasonal pH1N1 epidemics in humans. PMID:25833052

Continual Reintroduction of Human Pandemic H1N1 Influenza A Viruses into Swine in the United States, 2009 to 2014.

PubMed

Nelson, Martha I; Stratton, Jered; Killian, Mary Lea; Janas-Martindale, Alicia; Vincent, Amy L

2015-06-01

The diversity of influenza A viruses in swine (swIAVs) presents an important pandemic threat. Knowledge of the human-swine interface is particularly important for understanding how viruses with pandemic potential evolve in swine hosts. Through phylogenetic analysis of contemporary swIAVs in the United States, we demonstrate that human-to-swine transmission of pandemic H1N1 (pH1N1) viruses has occurred continuously in the years following the 2009 H1N1 pandemic and has been an important contributor to the genetic diversity of U.S. swIAVs. Although pandemic H1 and N1 segments had been largely removed from the U.S. swine population by 2013 via reassortment with other swIAVs, these antigens reemerged following multiple human-to-swine transmission events during the 2013-2014 seasonal epidemic. These findings indicate that the six internal gene segments from pH1N1 viruses are likely to be sustained long term in the U.S. swine population, with periodic reemergence of pandemic hemagglutinin (HA) and neuraminidase (NA) segments in association with seasonal pH1N1 epidemics in humans. Vaccinating U.S. swine workers may reduce infection of both humans and swine and in turn limit the role of humans as sources of influenza virus diversity in pigs. Swine are important hosts in the evolution of influenza A viruses with pandemic potential. Here, we analyze influenza virus sequence data generated by the U.S. Department of Agriculture's national surveillance system to identify the central role of humans in the reemergence of pandemic H1N1 (pH1N1) influenza viruses in U.S. swine herds in 2014. These findings emphasize the important role of humans as continuous sources of influenza virus diversity in swine and indicate that influenza viruses with pandemic HA and NA segments are likely to continue to reemerge in U.S. swine in association with seasonal pH1N1 epidemics in humans. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

UK newspapers' representations of the 2009-10 outbreak of swine flu: one health scare not over-hyped by the media?

PubMed

Hilton, Shona; Hunt, Kate

2011-10-01

A/H1N1, more commonly referred to as swine flu, emerged in Mexico in spring 2009. It rapidly spread across the world and was classed as a global pandemic on 11 June 2009. To analyse UK newsprint coverage of the swine flu pandemic. Content analysis of 2374 newsprint articles published in eight UK national newspapers between 1 March 2009 and 28 February 2010. Newsprint coverage of the swine flu epidemic was immense. The threat from swine flu was portrayed as greatest in the spring and summer of 2009 when scientific uncertainties about the impact on the UK and global population were at their height and when swine flu cases in the UK first peaked. Thereafter the number of news articles waned, failing to mirror the October peak in flu cases as the virus failed to be as virulent as first feared. Content analysis found little evidence of the media 'over-hyping' the swine flu pandemic. The news media's role as a disseminator of scientific information is particularly important in areas of risk perception. Despite a succession of health scares in recent years in which the media has been accused of exaggerating the risks and contributing to public misunderstandings of the issues, this analysis suggests that the UK newsprint reporting of swine flu in the 2009-10 outbreak was largely measured. The news media's role as disseminators of factual health information on swine flu is to be welcomed, particularly in relation to their handling and responsible reporting on scientific uncertainty.

Continual re-introduction of human pandemic H1N1 influenza A viruses into US swine, 2009-2014

USDA-ARS?s Scientific Manuscript database

Human-to-swine transmission of pandemic H1N1 influenza viruses (pH1N1) increased the genetic diversity of influenza A viruses in swine (swIAVs) globally and is linked to the emergence of new pandemic threats, including H3N2v variants. Through phylogenetic analysis of contemporary swIAVs in the Unit...

Swine Influenza Virus (H1N2) Characterization and Transmission in Ferrets, Chile.

PubMed

Bravo-Vasquez, Nicolás; Karlsson, Erik A; Jimenez-Bluhm, Pedro; Meliopoulos, Victoria; Kaplan, Bryan; Marvin, Shauna; Cortez, Valerie; Freiden, Pamela; Beck, Melinda A; Hamilton-West, Christopher; Schultz-Cherry, Stacey

2017-02-01

Phylogenetic analysis of the influenza hemagglutinin gene (HA) has suggested that commercial pigs in Chile harbor unique human seasonal H1-like influenza viruses, but further information, including characterization of these viruses, was unavailable. We isolated influenza virus (H1N2) from a swine in a backyard production farm in Central Chile and demonstrated that the HA gene was identical to that in a previous report. Its HA and neuraminidase genes were most similar to human H1 and N2 viruses from the early 1990s and internal segments were similar to influenza A(H1N1)pdm09 virus. The virus replicated efficiently in vitro and in vivo and transmitted in ferrets by respiratory droplet. Antigenically, it was distinct from other swine viruses. Hemagglutination inhibition analysis suggested that antibody titers to the swine Chilean H1N2 virus were decreased in persons born after 1990. Further studies are needed to characterize the potential risk to humans, as well as the ecology of influenza in swine in South America.

Swine Influenza Virus (H1N2) Characterization and Transmission in Ferrets, Chile

PubMed Central

Bravo-Vasquez, Nicolás; Karlsson, Erik A.; Jimenez-Bluhm, Pedro; Meliopoulos, Victoria; Kaplan, Bryan; Marvin, Shauna; Cortez, Valerie; Freiden, Pamela; Beck, Melinda A.

2017-01-01

Phylogenetic analysis of the influenza hemagglutinin gene (HA) has suggested that commercial pigs in Chile harbor unique human seasonal H1-like influenza viruses, but further information, including characterization of these viruses, was unavailable. We isolated influenza virus (H1N2) from a swine in a backyard production farm in Central Chile and demonstrated that the HA gene was identical to that in a previous report. Its HA and neuraminidase genes were most similar to human H1 and N2 viruses from the early 1990s and internal segments were similar to influenza A(H1N1)pdm09 virus. The virus replicated efficiently in vitro and in vivo and transmitted in ferrets by respiratory droplet. Antigenically, it was distinct from other swine viruses. Hemagglutination inhibition analysis suggested that antibody titers to the swine Chilean H1N2 virus were decreased in persons born after 1990. Further studies are needed to characterize the potential risk to humans, as well as the ecology of influenza in swine in South America. PMID:28098524

Antigenically Diverse Swine Origin H1N1 Variant Influenza Viruses Exhibit Differential Ferret Pathogenesis and Transmission Phenotypes.

PubMed

Pulit-Penaloza, Joanna A; Jones, Joyce; Sun, Xiangjie; Jang, Yunho; Thor, Sharmi; Belser, Jessica A; Zanders, Natosha; Creager, Hannah M; Ridenour, Callie; Wang, Li; Stark, Thomas J; Garten, Rebecca; Chen, Li-Mei; Barnes, John; Tumpey, Terrence M; Wentworth, David E; Maines, Taronna R; Davis, C Todd

2018-06-01

Influenza A(H1) viruses circulating in swine represent an emerging virus threat, as zoonotic infections occur sporadically following exposure to swine. A fatal infection caused by an H1N1 variant (H1N1v) virus was detected in a patient with reported exposure to swine and who presented with pneumonia, respiratory failure, and cardiac arrest. To understand the genetic and phenotypic characteristics of the virus, genome sequence analysis, antigenic characterization, and ferret pathogenesis and transmissibility experiments were performed. Antigenic analysis of the virus isolated from the fatal case, A/Ohio/09/2015, demonstrated significant antigenic drift away from the classical swine H1N1 variant viruses and H1N1 pandemic 2009 viruses. A substitution in the H1 hemagglutinin (G155E) was identified that likely impacted antigenicity, and reverse genetics was employed to understand the molecular mechanism of antibody escape. Reversion of the substitution to 155G, in a reverse genetics A/Ohio/09/2015 virus, showed that this residue was central to the loss of hemagglutination inhibition by ferret antisera raised against a prototypical H1N1 pandemic 2009 virus (A/California/07/2009), as well as gamma lineage classical swine H1N1 viruses, demonstrating the importance of this residue for antibody recognition of this H1 lineage. When analyzed in the ferret model, A/Ohio/09/2015 and another H1N1v virus, A/Iowa/39/2015, as well as A/California/07/2009, replicated efficiently in the respiratory tract of ferrets. The two H1N1v viruses transmitted efficiently among cohoused ferrets, but respiratory droplet transmission studies showed that A/California/07/2009 transmitted through the air more efficiently. Preexisting immunity to A/California/07/2009 did not fully protect ferrets from challenge with A/Ohio/09/2015. IMPORTANCE Human infections with classical swine influenza A(H1N1) viruses that circulate in pigs continue to occur in the United States following exposure to swine. To

Systemic lupus erythematosus (SLE) pneumonitis mimicking swine influenza pneumonia during the swine influenza (H1N1) pandemic.

PubMed

Cunha, Burke A; Syed, Uzma; Mickail, Nardeen

2011-01-01

We present a young woman with a negative medical history who presented with acute systemic lupus erythematosus (SLE) pneumonitis mimicking swine influenza (H1N1) pneumonia. Because this case occurred during the H1N1 pandemic, the initial diagnostic impression was of H1N1 pneumonia. Although her clinical and laboratory findings were consistent with the diagnosis of H1N1 pneumonia, e.g., fever, sore throat, dry cough, arthralgias, myalgias, thrombocytopenia, relative lymphopenia, and elevated serum transaminases, some findings suggested an alternate diagnosis, e.g., leukopenia, a highly elevated erythrocyte sedimentation rate, highly elevated serum ferritin levels, elevated antinuclear antibody (ANA) levels, and double-stranded (DS) DNA titers. Her chest x-ray showed an accentuation of basilar lung markings, with a small pleural effusion similar to the chest x-ray findings of early H1N1 pneumonia. Initially, her headaches were thought to be related to central nervous system manifestations of H1N1. After laboratory test results demonstrated elevated ANA and anti-DS DNA titers, she was diagnosed with acute SLE pneumonitis. The take-home lesson for clinicians is that other infectious diseases, e.g., human parainfluenza virus or Legionnaires' disease, can mimic H1N1 pneumonia during an influenza pandemic. Excluding asthma, congestive heart failure, exacerbations of acute bronchitis, chronic obstructive pulmonary disorder, and pulmonary interstitial disease, noninfectious mimics of H1N1 are extremely rare. To the best of our knowledge, this is the first reported case of de novo SLE pneumonitis mimicking H1N1 pneumonia during the swine influenza pandemic. Copyright © 2011 Elsevier Inc. All rights reserved.

Novel reassortant of swine influenza H1N2 virus in Germany.

PubMed

Zell, Roland; Motzke, Susann; Krumbholz, Andi; Wutzler, Peter; Herwig, Volker; Dürrwald, Ralf

2008-01-01

European porcine H1N2 influenza viruses arose after multiple reassortment steps involving a porcine influenza virus with avian-influenza-like internal segments and human H1N1 and H3N2 viruses in 1994. In Germany, H1N2 swine influenza viruses first appeared in 2000. Two German H1N2 swine influenza virus strains isolated from pigs with clinical symptoms of influenza are described. They were characterized by the neutralization test, haemagglutination inhibition (HI) test and complete sequencing of the viral genomes. The data demonstrate that these viruses represent a novel H1N2 reassortant. The viruses showed limited neutralization by sera raised against heterologous A/sw/Bakum/1,832/00-like H1N2 viruses. Sera pools from recovered pigs showed a considerably lower HI reaction, indicative of diagnostic difficulties in using the HI test to detect these viruses with A/sw/Bakum/1,832/00-like H1N2 antigens. Genome sequencing revealed the novel combination of the human-like HAH1 gene of European porcine H1N2 influenza viruses and the NAN2 gene of European porcine H3N2 viruses.

Genetic and biological characterisation of an avian-like H1N2 swine influenza virus generated by reassortment of circulating avian-like H1N1 and H3N2 subtypes in Denmark.

PubMed

Trebbien, Ramona; Bragstad, Karoline; Larsen, Lars Erik; Nielsen, Jens; Bøtner, Anette; Heegaard, Peter M H; Fomsgaard, Anders; Viuff, Birgitte; Hjulsager, Charlotte Kristiane

2013-09-18

The influenza A virus subtypes H1N1, H1N2 and H3N2 are the most prevalent subtypes in swine. In 2003, a reassorted H1N2 swine influenza virus (SIV) subtype appeared and became prevalent in Denmark. In the present study, the reassortant H1N2 subtype was characterised genetically and the infection dynamics compared to an "avian-like" H1N1 virus by an experimental infection study. Sequence analyses were performed of the H1N2 virus. Two groups of pigs were inoculated with the reassortant H1N2 virus and an "avian-like" H1N1 virus, respectively, followed by inoculation with the opposite subtype four weeks later. Measurements of HI antibodies and acute phase proteins were performed. Nasal virus excretion and virus load in lungs were determined by real-time RT-PCR. The phylogenetic analysis revealed that the reassorted H1N2 virus contained a European "avian-like" H1-gene and a European "swine-like" N2-gene, thus being genetically distinct from most H1N2 viruses circulating in Europe, but similar to viruses reported in 2009/2010 in Sweden and Italy. Sequence analyses of the internal genes revealed that the reassortment probably arose between circulating Danish "avian-like" H1N1 and H3N2 SIVs. Infected pigs developed cross-reactive antibodies, and increased levels of acute phase proteins after inoculations. Pigs inoculated with H1N2 exhibited nasal virus excretion for seven days, peaking day 1 after inoculation two days earlier than H1N1 infected pigs and at a six times higher level. The difference, however, was not statistically significant. Pigs euthanized on day 4 after inoculation, had a high virus load in all lung lobes. After the second inoculation, the nasal virus excretion was minimal. There were no clinical sign except elevated body temperature under the experimental conditions. The "avian-like" H1N2 subtype, which has been established in the Danish pig population at least since 2003, is a reassortant between circulating swine "avian-like" H1N1 and H3N2. The Danish

Swine Influenza (Swine Flu) in Pigs

MedlinePlus

... Address What's this? Submit What's this? Submit Button Influenza Types Seasonal Avian Swine Variant Pandemic Other Key Facts about Swine Influenza (Swine Flu) in Pigs Language: English (US) Español ...

Novel reassortant influenza A(H1N2) virus derived from A(H1N1)pdm09 virus isolated from swine, Japan, 2012.

PubMed

Kobayashi, Miho; Takayama, Ikuyo; Kageyama, Tsutomu; Tsukagoshi, Hiroyuki; Saitoh, Mika; Ishioka, Taisei; Yokota, Yoko; Kimura, Hirokazu; Tashiro, Masato; Kozawa, Kunihisa

2013-12-01

We isolated a novel influenza virus A(H1N2) strain from a pig on January 13, 2012, in Gunma Prefecture, Japan. Phylogenetic analysis showed that the strain was a novel type of double-reassortant virus derived from the swine influenza virus strains H1N1pdm09 and H1N2, which were prevalent in Gunma at that time.

Virological and serological study of human infection with swine influenza A H1N1 virus in China.

PubMed

Zu, Rongqiang; Dong, Libo; Qi, Xian; Wang, Dayan; Zou, Shumei; Bai, Tian; Li, Ming; Li, Xiaodan; Zhao, Xiang; Xu, Cuiling; Huo, Xiang; Xiang, Nijuan; Yang, Shuai; Li, Zi; Xu, Zhen; Wang, Hua; Shu, Yuelong

2013-11-01

Pigs are considered to be "mixing vessels" for the emergence of influenza viruses with pandemic potential. 2009 Pandemic Influenza H1N1 further proved this hypothesis, and raised the needs for risk assessment of human cases caused by swine influenza virus. A field investigation was conducted after a case identified with infection of European avian-like swine influenza H1N1 virus. The diagnosis was confirmed by real-time PCR, virus isolation, whole genome sequencing and serological assays. Samples from local pigs and close contacts were tested to identify the source of infection and route of transmission. The virus from the index case was similar to viruses circulating in the local pigs. The case's grandfather was asymptomatic with sero-conversion. A total of 42.8% of swine sera were positive for European avian-like swine H1N1. This study highlighted the importance of performing surveillance on swine influenza to monitor new virus emergence in humans. © 2013 Elsevier Inc. All rights reserved.

Novel Reassortant Influenza A(H1N2) Virus Derived from A(H1N1)pdm09 Virus Isolated from Swine, Japan, 2012

PubMed Central

Kobayashi, Miho; Takayama, Ikuyo; Kageyama, Tsutomu; Tsukagoshi, Hiroyuki; Saitoh, Mika; Ishioka, Taisei; Yokota, Yoko; Kimura, Hirokazu; Tashiro, Masato

2013-01-01

We isolated a novel influenza virus A(H1N2) strain from a pig on January 13, 2012, in Gunma Prefecture, Japan. Phylogenetic analysis showed that the strain was a novel type of double-reassortant virus derived from the swine influenza virus strains H1N1pdm09 and H1N2, which were prevalent in Gunma at that time. PMID:24274745

Human temperatures for syndromic surveillance in the emergency department: data from the autumn wave of the 2009 swine flu (H1N1) pandemic and a seasonal influenza outbreak.

PubMed

Bordonaro, Samantha F; McGillicuddy, Daniel C; Pompei, Francesco; Burmistrov, Dmitriy; Harding, Charles; Sanchez, Leon D

2016-03-09

The emergency department (ED) increasingly acts as a gateway to the evaluation and treatment of acute illnesses. Consequently, it has also become a key testing ground for systems that monitor and identify outbreaks of disease. Here, we describe a new technology that automatically collects body temperatures during triage. The technology was tested in an ED as an approach to monitoring diseases that cause fever, such as seasonal flu and some pandemics. Temporal artery thermometers that log temperature measurements were placed in a Boston ED and used for initial triage vital signs. Time-stamped measurements were collected from the thermometers to investigate the performance a real-time system would offer. The data were summarized in terms of rates of fever (temperatures ≥100.4 °F [≥38.0 °C]) and were qualitatively compared with regional disease surveillance programs in Massachusetts. From September 2009 through August 2011, 71,865 body temperatures were collected and included in our analysis, 2073 (2.6 %) of which were fevers. The period of study included the autumn-winter wave of the 2009-2010 H1N1 (swine flu) pandemic, during which the weekly incidence of fever reached a maximum of 5.6 %, as well as the 2010-2011 seasonal flu outbreak, during which the maximum weekly incidence of fever was 6.6 %. The periods of peak fever rates corresponded with the periods of regionally elevated flu activity. Temperature measurements were monitored at triage in the ED over a period of 2 years. The resulting data showed promise as a potential surveillance tool for febrile disease that could complement current disease surveillance systems. Because temperature can easily be measured by non-experts, it might also be suitable for monitoring febrile disease activity in schools, workplaces, and transportation hubs, where many traditional syndromic indicators are impractical. However, the system's validity and generalizability should be evaluated in additional years and

Influenza A Viruses Detected in Swine in Southern Germany after the H1N1 Pandemic in 2009.

PubMed

Pippig, J; Ritzmann, M; Büttner, M; Neubauer-Juric, A

2016-11-01

Infections with influenza A viruses (IAV) are highly prevalent in swine populations, and stable cocirculation of at least three lineages has been well documented in European swine - till 2009. However, since the emergence of the human pandemic pdmH1N1 virus in 2009, which has been (re)introduced into individual swine herds worldwide, the situation has been changing. These variations in the respective IAV pools within pig populations are of major interest, and the zoonotic potential of putative emerging viruses needs to be evaluated. As data on recent IAV in swine from southern Germany were relatively sparse, the purpose of this study was to determine the major IAV subtypes actually present in this region. To this aim, from 2010 to 2013, 1417 nasal swabs or lung tissue samples from pigs with respiratory disease were screened for IAV genomes. Overall, in 130 holdings IAV genomes were detected by real-time RT-PCR targeting the matrix protein gene. For further analyses, several PCR protocols were adapted to quickly subtype between H1, pdmH1, H3, N1 and N2 sequences. Taken together, cocirculation of the three stable European lineages of IAV was confirmed for Bavaria. H1N1 sequences were identified in 59, whereas H1N2 genomes were only diagnosed in 14, and H3N2 in 9 of the holdings analysed. However, pdmH1 in combination with N1 was detected in 2010, 2012 and 2013 confirming a presence, albeit in low prevalence, likewise pdmH1N2 reassortant viruses. Interestingly, individual cases of coinfections with more than one subtype were diagnosed. Partial genome sequences were determined and phylogenetic analyses performed. Clearly other than in the human population classically circulating IAV have not been displaced by pdmH1N1 in Bavarian swine. However, some interesting viruses were detected. Further surveillance of these viruses in the Bavarian pig population will be of major importance, to monitor future developments. © 2016 Blackwell Verlag GmbH.

Crying wolf? Biosecurity and metacommunication in the context of the 2009 swine flu pandemic.

PubMed

Nerlich, Brigitte; Koteyko, Nelya

2012-07-01

This article explores how the 2009 pandemic of swine flu (H1N1) intersected with issues of biosecurity in the context of an increasing entanglement between the spread of disease and the spread of information. Drawing on research into metacommunication, the article studies the rise of communication about ways in which swine flu was communicated, both globally and locally, during the pandemic. It examines and compares two corpora of texts, namely UK newspaper articles and blogs, written between 28 March and 11 June 2009, that is, the period from the start of the outbreak till the WHO announcement of the pandemic. Findings show that the interaction between traditional and digital media as well as the interaction between warnings about swine flu and previous warnings about other epidemics contributed to a heightened discourse of blame and counter-blame but also, more surprisingly, self-blame and reflections about the role the media in pandemic communication. The consequences of this increase in metacommunication for research into crisis communication are explored. Copyright © 2011 Elsevier Ltd. All rights reserved.

New Influenza A/H1N1 (“Swine Flu”): information needs of airport passengers and staff

PubMed Central

Dickmann, P.; Rubin, G. J.; Gaber, W.; Wessely, S.; Wicker, S.; Serve, H.; Gottschalk, R.

2010-01-01

Please cite this paper as: Dickmann et al. (2010) New Influenza A/H1N1 (“Swine Flu”): information needs of airport passengers and staff. . Influenza and Other Respiratory Viruses 5(1), 39–46. Background  Airports are the entrances of infectious diseases. Particularly at the beginning of an outbreak, information and communication play an important role to enable the early detection of signs or symptoms and to encourage passengers to adopt appropriate preventive behaviour to limit the spread of the disease. Objectives  To determine the adequacy of the information provided to airport passengers and staff in meeting their information needs in relation to their concerns. Methods  At the start of the influenza A/H1N1 epidemic (29–30 April 2009), qualitative semi‐structured interviews (N = 101) were conducted at Frankfurt International Airport with passengers who were either returning from or going to Mexico and with airport staff who had close contact with these passengers. Interviews focused on knowledge about swine flu, information needs and fear or concern about the outbreak. Results  The results showed that a desire for more information was associated with higher concern – the least concerned participants did not want any additional information, while the most concerned participants reported a range of information needs. Airport staff in contact with passengers travelling from the epicentre of the outbreak showed the highest levels of fear or concern, coupled with a desire to be adequately briefed by their employer. Conclusions  Our results suggest that information strategies should address not only the exposed or potentially exposed but also groups that feel at risk. Identifying what information these different passenger and staff groups wish to receive will be an important task in any future infectious disease outbreak. PMID:21138539

An effective quarantine measure reduced the total incidence of influenza A H1N1 in the workplace: another way to control the H1N1 flu pandemic.

PubMed

Miyaki, Koichi; Sakurazawa, Hirofumi; Mikurube, Hajime; Nishizaka, Mika; Ando, Hidehiko; Song, Yixuan; Shimbo, Takuro

2011-01-01

To evaluate the effectiveness of a non-vaccine quarantine measure against pandemic influenza A H1N1 in workplaces. Design was quasi-cluster randomized controlled trial in two sibling companies (Cohort 1 n=6,634, Cohort 2 n=8,500). The follow-up period was from July 1st, 2009 to February 19th, 2010 (233 days). Intervention was voluntary waiting at home on full pay if the family became Influenza like Illness (ILI). The incidences of influenza A H1N1 and those of the subgroups whose families got ILI in both cohorts were compared by a Cox regression model and log-rank test. There were 189 and 270 workers who got H1N1 infection during the follow-up period in each cohort. In this period 317 workers in Cohort 1 were asked to wait at home for several days (100% obeyed). The intervention group (Cohort 1) showed a statistically significant lower risk (p for log-rank test=0.033) compared with the control (Cohort 2), and the hazard ratio of the intervention was 0.799 [0.658-0.970] after adjusting for age, sex, BMI and smoking status. The workers who were asked to wait at home showed H1N1 infection more frequently (49 out of 317) compared with the workers whose family got ILI but were not asked to wait and work regularly (77 out of 990, RR=2.17 [1.48-3.18]). The waiting on full pay policy in the workplace reduced the overall risk of influenza A H1N1 by about 20% in one flu season in Japan. This kind of non-vaccine measure will be a promising option in workplaces to control the next flu pandemic.

A novel monoclonal antibody effective against lethal challenge with swine-lineage and 2009 pandemic H1N1 influenza viruses in mice

USDA-ARS?s Scientific Manuscript database

The HA protein of the 2009 pandemic H1N1viruses (14 H1N1pdm) is antigenically closely related to the HA of classical North American swine H1N1 influenza viruses (cH1N1). Since 1998, through reassortment and incorporation of HA genes from human H3N2 and H1N1 influenza viruses, swine influenza strains...

Protection of guinea pigs by vaccination with a recombinant swinepox virus co-expressing HA1 genes of swine H1N1 and H3N2 influenza viruses.

PubMed

Xu, Jiarong; Yang, Deji; Huang, Dongyan; Xu, Jiaping; Liu, Shichao; Lin, Huixing; Zhu, Haodan; Liu, Bao; Lu, Chengping

2013-03-01

Swine influenza (SI) is an acute respiratory infectious disease of swine caused by swine influenza virus (SIV). SIV is not only an important respiratory pathogen in pigs but also a potent threat to human health. Here, we report the construction of a recombinant swinepox virus (rSPV/H3-2A-H1) co-expressing hemagglutinin (HA1) of SIV subtypes H1N1 and H3N2. Immune responses and protection efficacy of the rSPV/H3-2A-H1 were evaluated in guinea pigs. Inoculation of rSPV/H3-2A-H1 yielded neutralizing antibodies against SIV H1N1 and H3N2. The IFN-γ and IL-4 concentrations in the supernatant of lymphocytes stimulated with purified SIV HA1 antigen were significantly higher (P < 0.01) than those of the control groups. Complete protection of guinea pigs against SIV H1N1 or H3N2 challenge was observed. No SIV shedding was detected from guinea pigs vaccinated with rSPV/H3-2A-H1 after challenge. Most importantly, the guinea pigs immunized with rSPV/H3-2A-H1 did not show gross and micrographic lung lesions. However, the control guinea pigs experienced distinct gross and micrographic lung lesions at 7 days post-challenge. Our data suggest that the recombinant swinepox virus encoding HA1 of SIV H1N1 and H3N2 might serve as a promising candidate vaccine for protection against SIV H1N1 and H3N2 infections.

Viral reassortment and transmission after co-infection of pigs with classical H1N1 and triple-reassortant H3N2 swine influenza viruses.

PubMed

Ma, Wenjun; Lager, Kelly M; Lekcharoensuk, Porntippa; Ulery, Eva S; Janke, Bruce H; Solórzano, Alicia; Webby, Richard J; García-Sastre, Adolfo; Richt, Jürgen A

2010-09-01

Triple-reassortant swine influenza viruses circulating in North American pigs contain the internal genes derived from swine (matrix, non-structural and nucleoprotein), human [polymerase basic 1 (PB1)] and avian (polymerase acidic and PB2) influenza viruses forming a constellation of genes that is well conserved and is called the triple-reassortant internal gene (TRIG) cassette. In contrast, the external genes [haemagglutinin (HA) and neuraminidase (NA)] are less conserved, reflecting multiple reassortant events that have produced viruses with different combinations of HA and NA genes. This study hypothesized that maintenance of the TRIG cassette confers a selective advantage to the virus. To test this hypothesis, pigs were co-infected with the triple-reassortant H3N2 A/Swine/Texas/4199-2/98 (Tx/98) and the classical H1N1 A/Swine/Iowa/15/1930 viruses and co-housed with a group of sentinel animals. This direct contact group was subsequently moved into contact with a second group of naïve animals. Four different subtypes (H1N1, H1N2, H3N1 and H3N2) of influenza virus were identified in bronchoalveolar lavage fluid collected from the lungs of the experimentally infected pigs, with most of the viruses containing TRIG from the Tx/98 virus. Interestingly, only the intact H3N2 Tx/98 virus was transmitted from the infected pigs to the direct-contact animals and from them to the second contact group of pigs. These results demonstrated that multiple reassortments can occur within a host; however, only specific gene constellations are readily transmissible. It was concluded that certain HA and NA gene pairs, in conjunction with the TRIG cassette, may have a competitive advantage over other combinations for transmission and maintenance in swine.

Reassortment between Swine H3N2 and 2009 Pandemic H1N1 in the United States Resulted in Influenza A Viruses with Diverse Genetic Constellations with Variable Virulence in Pigs

PubMed Central

Rajão, Daniela S.; Walia, Rasna R.; Campbell, Brian; Gauger, Phillip C.; Janas-Martindale, Alicia; Killian, Mary Lea

2016-01-01

ABSTRACT Repeated spillovers of the H1N1 pandemic virus (H1N1pdm09) from humans to pigs resulted in substantial evolution of influenza A viruses infecting swine, contributing to the genetic and antigenic diversity of influenza A viruses (IAV) currently circulating in swine. The reassortment with endemic swine viruses and maintenance of some of the H1N1pdm09 internal genes resulted in the circulation of different genomic constellations in pigs. Here, we performed a whole-genome phylogenetic analysis of 368 IAV circulating in swine from 2009 to 2016 in the United States. We identified 44 different genotypes, with the most common genotype (32.33%) containing a clade IV-A HA gene, a 2002-lineage NA gene, an M-pdm09 gene, and remaining gene segments of triple reassortant internal gene (TRIG) origin. To understand how different genetic constellations may relate to viral fitness, we compared the pathogenesis and transmission in pigs of six representative genotypes. Although all six genotypes efficiently infected pigs, they resulted in different degrees of pathology and viral shedding. These results highlight the vast H3N2 genetic diversity circulating in U.S. swine after 2009. This diversity has important implications in the control of this disease by the swine industry, as well as a potential risk for public health if swine-adapted viruses with H1N1pdm09 genes have an increased risk to humans, as occurred in the 2011-2012 and 2016 human variant H3N2v cases associated with exhibition swine. IMPORTANCE People continue to spread the 2009 H1N1 pandemic (H1N1pdm09) IAV to pigs, allowing H1N1pdm09 to reassort with endemic swine IAV. In this study, we determined the 8 gene combinations of swine H3N2 IAV detected from 2009 to 2016. We identified 44 different genotypes of H3N2, the majority of which contained at least one H1N1pdm09 gene segment. We compared six representative genotypes of H3N2 in pigs. All six genotypes efficiently infected pigs, but they resulted in different

Reassortment between Swine H3N2 and 2009 Pandemic H1N1 in the United States Resulted in Influenza A Viruses with Diverse Genetic Constellations with Variable Virulence in Pigs.

PubMed

Rajão, Daniela S; Walia, Rasna R; Campbell, Brian; Gauger, Phillip C; Janas-Martindale, Alicia; Killian, Mary Lea; Vincent, Amy L

2017-02-15

Repeated spillovers of the H1N1 pandemic virus (H1N1pdm09) from humans to pigs resulted in substantial evolution of influenza A viruses infecting swine, contributing to the genetic and antigenic diversity of influenza A viruses (IAV) currently circulating in swine. The reassortment with endemic swine viruses and maintenance of some of the H1N1pdm09 internal genes resulted in the circulation of different genomic constellations in pigs. Here, we performed a whole-genome phylogenetic analysis of 368 IAV circulating in swine from 2009 to 2016 in the United States. We identified 44 different genotypes, with the most common genotype (32.33%) containing a clade IV-A HA gene, a 2002-lineage NA gene, an M-pdm09 gene, and remaining gene segments of triple reassortant internal gene (TRIG) origin. To understand how different genetic constellations may relate to viral fitness, we compared the pathogenesis and transmission in pigs of six representative genotypes. Although all six genotypes efficiently infected pigs, they resulted in different degrees of pathology and viral shedding. These results highlight the vast H3N2 genetic diversity circulating in U.S. swine after 2009. This diversity has important implications in the control of this disease by the swine industry, as well as a potential risk for public health if swine-adapted viruses with H1N1pdm09 genes have an increased risk to humans, as occurred in the 2011-2012 and 2016 human variant H3N2v cases associated with exhibition swine. People continue to spread the 2009 H1N1 pandemic (H1N1pdm09) IAV to pigs, allowing H1N1pdm09 to reassort with endemic swine IAV. In this study, we determined the 8 gene combinations of swine H3N2 IAV detected from 2009 to 2016. We identified 44 different genotypes of H3N2, the majority of which contained at least one H1N1pdm09 gene segment. We compared six representative genotypes of H3N2 in pigs. All six genotypes efficiently infected pigs, but they resulted in different degrees of lung damage

Genetic and biological characterisation of an avian-like H1N2 swine influenza virus generated by reassortment of circulating avian-like H1N1 and H3N2 subtypes in Denmark

PubMed Central

2013-01-01

Background The influenza A virus subtypes H1N1, H1N2 and H3N2 are the most prevalent subtypes in swine. In 2003, a reassorted H1N2 swine influenza virus (SIV) subtype appeared and became prevalent in Denmark. In the present study, the reassortant H1N2 subtype was characterised genetically and the infection dynamics compared to an “avian-like” H1N1 virus by an experimental infection study. Methods Sequence analyses were performed of the H1N2 virus. Two groups of pigs were inoculated with the reassortant H1N2 virus and an “avian-like” H1N1 virus, respectively, followed by inoculation with the opposite subtype four weeks later. Measurements of HI antibodies and acute phase proteins were performed. Nasal virus excretion and virus load in lungs were determined by real-time RT-PCR. Results The phylogenetic analysis revealed that the reassorted H1N2 virus contained a European “avian-like” H1-gene and a European “swine-like” N2-gene, thus being genetically distinct from most H1N2 viruses circulating in Europe, but similar to viruses reported in 2009/2010 in Sweden and Italy. Sequence analyses of the internal genes revealed that the reassortment probably arose between circulating Danish “avian-like” H1N1 and H3N2 SIVs. Infected pigs developed cross-reactive antibodies, and increased levels of acute phase proteins after inoculations. Pigs inoculated with H1N2 exhibited nasal virus excretion for seven days, peaking day 1 after inoculation two days earlier than H1N1 infected pigs and at a six times higher level. The difference, however, was not statistically significant. Pigs euthanized on day 4 after inoculation, had a high virus load in all lung lobes. After the second inoculation, the nasal virus excretion was minimal. There were no clinical sign except elevated body temperature under the experimental conditions. Conclusions The “avian-like” H1N2 subtype, which has been established in the Danish pig population at least since 2003, is a reassortant

Reassortment process after co-infection of pigs with avian H1N1 and swine H3N2 influenza viruses.

PubMed

Urbaniak, Kinga; Markowska-Daniel, Iwona; Kowalczyk, Andrzej; Kwit, Krzysztof; Pomorska-Mól, Małgorzata; Frącek, Barbara; Pejsak, Zygmunt

2017-07-08

The influenza A virus is highly variable, which, to some degree, is caused by the reassortment of viral genetic material. This process plays a major role in the generation of novel influenza virus strains that can emerge in a new host population. Due to the susceptibility of pigs to infections with avian, swine and human influenza viruses, they are considered intermediate hosts for the adaptation of the avian influenza virus to humans. In order to test the reassortment process in pigs, they were co-infected with H3N2 A/swine/Gent/172/2008 (Gent/08) and H1N1 A/duck/Italy/1447/2005 (Italy/05) and co-housed with a group of naïve piglets. The Gent/08 strains dominated over Italy/05, but reassortment occurred. The reassortant strains of the H1N1 subtype (12.5%) with one gene (NP or M) of swine-origin were identified in the nasal discharge of the contact-exposed piglets. These results demonstrate that despite their low efficiency, genotypically and phenotypically different influenza A viruses can undergo genetic exchange during co-infection of pigs.

Genetic Characterization and Evolution of H1N1pdm09 after Circulation in a Swine Farm

PubMed Central

Boni, Arianna; Vaccari, Gabriele; Di Trani, Livia; Zaccaria, Guendalina; Alborali, Giovanni Loris; Lelli, Davide; Cordioli, Paolo; Moreno, Ana Maria

2014-01-01

Following the emergence of the A(H1N1)pdm09 in humans, this novel influenza virus was reverse transmitted from infected people to swine population worldwide. In this study we investigated the molecular evolution of A(H1N1)pdm09 virus identified in pigs reared in a single herd. Nasal swabs taken from pigs showing respiratory distress were tested for influenza type A and A(H1N1)pdm09 by real-time RT-PCR assays. Virus isolation from positive samples was attempted by inoculation of nasal swabs samples into specific pathogen free embryonated chicken eggs (ECE) and complete genome sequencing was performed on virus strains after replication on ECE or from original swab sample. The molecular analysis of hemagglutinin (HA) showed, in four of the swine influenza viruses under study, a unique significant amino acid change, represented by a two-amino acid insertion at the HA receptor binding site. Phylogenetic analysis of HA, neuraminidase, and concatenated internal genes revealed a very similar topology, with viruses under study forming a separate cluster, branching outside the A(H1N1)pdm09 isolates recognized until 2014. The emergence of this new cluster of A(H1N1)pdm09 in swine raises further concerns about whether A(H1N1)pdm09 with new molecular characteristics will become established in pigs and potentially transmitted to humans. PMID:25025062

Public anxiety and information seeking following the H1N1 outbreak: blogs, newspaper articles, and Wikipedia visits.

PubMed

Tausczik, Yla; Faasse, Kate; Pennebaker, James W; Petrie, Keith J

2012-01-01

Web-based methodologies may provide a new and unique insight into public response to an infectious disease outbreak. This naturalistic study investigates the effectiveness of new web-based methodologies in assessing anxiety and information seeking in response to the 2009 H1N1 outbreak by examining language use in weblogs ("blogs"), newspaper articles, and web-based information seeking. Language use in blogs and newspaper articles was assessed using Linguistic Inquiry and Word Count, and information seeking was examined using the number of daily visits to H1N1-relevant Wikipedia articles. The results show that blogs mentioning "swine flu" used significantly higher levels of anxiety, health, and death words and lower levels of positive emotion words than control blogs. Change in language use on blogs was strongly related to change in language use in newspaper coverage for the same day. Both the measure of anxiety in blogs mentioning "swine flu" and the number of Wikipedia visits followed similar trajectories, peaking shortly after the announcement of H1N1 and then declining rapidly. Anxiety measured in blogs preceded information seeking on Wikipedia. These results show that the public reaction to H1N1 was rapid and short-lived. This research suggests that analysis of web behavior can provide a source of naturalistic data on the level and changing pattern of public anxiety and information seeking following the outbreak of a public health emergency.

Immune efficacy of an adenoviral vector-based swine influenza vaccine against antigenically distinct H1N1 strains in mice.

PubMed

Wu, Yunpu; Yang, Dawei; Xu, Bangfeng; Liang, Wenhua; Sui, Jinyu; Chen, Yan; Yang, Huanliang; Chen, Hualan; Wei, Ping; Qiao, Chuanling

2017-11-01

Avian-like H1N1 swine influenza viruses are prevalent in pigs and have occasionally crossed the species barrier and infected humans, which highlights the importance of preventing swine influenza. Human adenovirus serotype 5 (Ad5) has been tested in human influenza vaccine clinical trials and has exhibited a reliable safety profile. Here, we generated a replication-defective, recombinant adenovirus (designated as rAd5-avH1HA) expressing the hemagglutinin gene of an avian-like H1N1 virus (A/swine/Zhejiang/199/2013, ZJ/199/13). Using a BALB/c mouse model, we showed that a two-dose intramuscular administration of recombinant rAd5-avH1HA induced high levels of hemagglutination inhibition antibodies and prevented homologous and heterologous H1N1 virus-induced weight loss, as well as viral replication in the nasal turbinates and lungs of mice. Furthermore, a prime-boost immunization strategy trial with a recombinant plasmid (designated as pCAGGS-HA) followed by rAd5-avH1HA vaccine provided effective protection against homologous and heterologous H1N1 virus infection in mice. These results indicate that rAd5-avH1HA is an efficacious genetically engineered vaccine candidate against H1N1 swine influenza. Future studies should examine its immune efficacy in pigs. Copyright © 2017 Elsevier B.V. All rights reserved.

Reassortment between swine H3N2 and 2009 pandemic H1N1 generated diverse genetic constellations in influenza A viruses currently circulating in pigs in the United States

USDA-ARS?s Scientific Manuscript database

Introduction Influenza A virus (IAV) is a significant pathogen to the swine industry. Since its introduction in 2009, the H1N1 pandemic virus (H1N1pdm09) has been repeatedly transmitted from humans to swine, but onward transmission in U.S. swine was mostly restricted to its internal genes. Reassortm...

Frequent global transmission of H1N1pdm09 influenza viruses from humans to swine, 2009-2011

USDA-ARS?s Scientific Manuscript database

Using a large-scale phylogenetic approach we identify at least 52 human-to-swine transmission events of pandemic A/H1N1/09 influenza virus. These results highlight the global frequency of swine exposure to human influenza viruses and the permeability of the human-swine species barrier, even followin...

The origin of the PB1 segment of swine influenza A virus subtype H1N2 determines viral pathogenicity in mice

PubMed Central

Metreveli, Giorgi; Gao, Qinshan; Mena, Nacho; Schmolke, Mirco; Berg, Mikael; Albrecht, Randy A.; García-Sastre, Adolfo

2017-01-01

Swine appear to be a key species in the generation of novel human influenza pandemics. Previous pandemic viruses are postulated to have evolved in swine by reassortment of avian, human, and swine influenza viruses. The human pandemic influenza viruses that emerged in 1957 and 1968 as well as swine viruses circulating since 1998 encode PB1 segments derived from avian influenza viruses. Here we investigate the possible role in viral replication and virulence of the PB1 gene segments present in two swine H1N2 influenza A viruses, A/swine/Sweden/1021/2009(H1N2) (sw 1021) and A/swine/Sweden/9706/2010(H1N2) (sw 9706), where the sw 1021 virus has shown to be more pathogenic in mice. By using reverse genetics, we swapped the PB1 genes of these two viruses. Similar to the sw 9706 virus, chimeric sw 1021 virus carrying the sw 9706 PB1 gene was not virulent in mice. In contrast, replacement of the PB1 gene of the sw 9706 virus by that from sw 1021 virus resulted in increased pathogenicity. Our study demonstrated that differences in virulence of swine influenza virus subtype H1N2 are attributed at least in part to the PB1 segment. PMID:24726997

Insights into the increasing virulence of the swine-origin pandemic H1N1/2009 influenza virus

PubMed Central

Zou, Wei; Chen, Dijun; Xiong, Min; Zhu, Jiping; Lin, Xian; Wang, Lun; Zhang, Jun; Chen, Lingling; Zhang, Hongyu; Chen, Huanchun; Chen, Ming; Jin, Meilin

2013-01-01

Pandemic H1N1/2009 viruses have been stabilized in swine herds, and some strains display higher pathogenicity than the human-origin isolates. In this study, high-throughput RNA sequencing (RNA-seq) is applied to explore the systemic transcriptome responses of the mouse lungs infected by swine (Jia6/10) and human (LN/09) H1N1/2009 viruses. The transcriptome data show that Jia6/10 activates stronger virus-sensing signals, such as the toll-like receptor, RIG-I like receptor and NOD-like receptor signalings, as well as a stronger NF-κB and JAK-STAT singals, which play significant roles in inducing innate immunity. Most cytokines and interferon-stimulated genes show higher expression lever in Jia/06 infected groups. Meanwhile, virus Jia6/10 activates stronger production of reactive oxygen species, which might further promote higher mutation rate of the virus genome. Collectively, our data reveal that the swine-origin pandemic H1N1/2009 virus elicits a stronger innate immune reaction and pro-oxidation stimulation, which might relate closely to the increasing pathogenicity. PMID:23549303

Assessment of H1N1 questions and answers posted on the Web.

PubMed

Kim, Sujin; Pinkerton, Thomas; Ganesh, Nithya

2012-04-01

A novel strain of human influenza A (H1N1) posed a serious pandemic threat worldwide during 2009. The public's fear of pandemic flu often raises awareness and discussion of such events. The goal of this study was to characterize major topical matters of H1N1 questions and answers raised by the online question and answer community Yahoo! Answers during H1N1 outbreak. The study used Text Mining for SPSS Clementine (v.12; SPSS Inc., Chicago, IL) to extract the major concepts of the collected Yahoo! questions and answers. The original collections were retrieved using "H1N1" in search, keyword and then filtered for only "resolved questions" in the "health" category submitted within the past 2 years. The most frequently formed categories were as follows: general health (health, disease, medicine, investigation, evidence, problem), flu-specific terms (H1N1, swine, shot, fever, cold, infective, throat), and nonmedical issues (feel, North American, people, child, nations, government, states, help, doubt, emotion). The study found that URL data are fairly predictable: those providing answers are divided between ones dedicated to giving trustworthy information-from news organizations and the government, for instance-and those looking to espouse a more biased point of view. Critical evaluation of online sources should be taught to select the quality of information and improve health literacy. The challenges of pandemic prevention and control, therefore, demand both e-surveillance and better informed "Netizens." Copyright © 2012 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

H1N1 Swine Influenza Viruses Differ from Avian Precursors by a Higher pH Optimum of Membrane Fusion.

PubMed

Baumann, Jan; Kouassi, Nancy Mounogou; Foni, Emanuela; Klenk, Hans-Dieter; Matrosovich, Mikhail

2016-02-01

The H1N1 Eurasian avian-like swine (EAsw) influenza viruses originated from an avian H1N1 virus. To characterize potential changes in the membrane fusion activity of the hemagglutinin (HA) during avian-to-swine adaptation of the virus, we studied EAsw viruses isolated in the first years of their circulation in pigs and closely related contemporary H1N1 viruses of wild aquatic birds. Compared to the avian viruses, the swine viruses were less sensitive to neutralization by lysosomotropic agent NH4Cl in MDCK cells, had a higher pH optimum of hemolytic activity, and were less stable at acidic pH. Eight amino acid substitutions in the HA were found to separate the EAsw viruses from their putative avian precursor; four substitutions-T492S, N722D, R752K, and S1132F-were located in the structural regions of the HA2 subunit known to play a role in acid-induced conformational transition of the HA. We also studied low-pH-induced syncytium formation by cell-expressed HA proteins and found that the HAs of the 1918, 1957, 1968, and 2009 pandemic viruses required a lower pH for fusion induction than did the HA of a representative EAsw virus. Our data show that transmission of an avian H1N1 virus to pigs was accompanied by changes in conformational stability and fusion promotion activity of the HA. We conclude that distinctive host-determined fusion characteristics of the HA may represent a barrier for avian-to-swine and swine-to-human transmission of influenza viruses. Continuing cases of human infections with zoonotic influenza viruses highlight the necessity to understand which viral properties contribute to interspecies transmission. Efficient binding of the HA to cellular receptors in a new host species is known to be essential for the transmission. Less is known about required adaptive changes in the membrane fusion activity of the HA. Here we show that adaptation of an avian influenza virus to pigs in Europe in 1980s was accompanied by mutations in the HA, which decreased

H1N1 Swine Influenza Viruses Differ from Avian Precursors by a Higher pH Optimum of Membrane Fusion

PubMed Central

Baumann, Jan; Kouassi, Nancy Mounogou; Foni, Emanuela; Klenk, Hans-Dieter

2015-01-01

ABSTRACT The H1N1 Eurasian avian-like swine (EAsw) influenza viruses originated from an avian H1N1 virus. To characterize potential changes in the membrane fusion activity of the hemagglutinin (HA) during avian-to-swine adaptation of the virus, we studied EAsw viruses isolated in the first years of their circulation in pigs and closely related contemporary H1N1 viruses of wild aquatic birds. Compared to the avian viruses, the swine viruses were less sensitive to neutralization by lysosomotropic agent NH4Cl in MDCK cells, had a higher pH optimum of hemolytic activity, and were less stable at acidic pH. Eight amino acid substitutions in the HA were found to separate the EAsw viruses from their putative avian precursor; four substitutions—T492S, N722D, R752K, and S1132F—were located in the structural regions of the HA2 subunit known to play a role in acid-induced conformational transition of the HA. We also studied low-pH-induced syncytium formation by cell-expressed HA proteins and found that the HAs of the 1918, 1957, 1968, and 2009 pandemic viruses required a lower pH for fusion induction than did the HA of a representative EAsw virus. Our data show that transmission of an avian H1N1 virus to pigs was accompanied by changes in conformational stability and fusion promotion activity of the HA. We conclude that distinctive host-determined fusion characteristics of the HA may represent a barrier for avian-to-swine and swine-to-human transmission of influenza viruses. IMPORTANCE Continuing cases of human infections with zoonotic influenza viruses highlight the necessity to understand which viral properties contribute to interspecies transmission. Efficient binding of the HA to cellular receptors in a new host species is known to be essential for the transmission. Less is known about required adaptive changes in the membrane fusion activity of the HA. Here we show that adaptation of an avian influenza virus to pigs in Europe in 1980s was accompanied by mutations in

The origin of the PB1 segment of swine influenza A virus subtype H1N2 determines viral pathogenicity in mice.

PubMed

Metreveli, Giorgi; Gao, Qinshan; Mena, Ignacio; Schmolke, Mirco; Berg, Mikael; Albrecht, Randy A; García-Sastre, Adolfo

2014-08-08

Swine appear to be a key species in the generation of novel human influenza pandemics. Previous pandemic viruses are postulated to have evolved in swine by reassortment of avian, human, and swine influenza viruses. The human pandemic influenza viruses that emerged in 1957 and 1968 as well as swine viruses circulating since 1998 encode PB1 segments derived from avian influenza viruses. Here we investigate the possible role in viral replication and virulence of the PB1 gene segments present in two swine H1N2 influenza A viruses, A/swine/Sweden/1021/2009(H1N2) (sw 1021) and A/swine/Sweden/9706/2010(H1N2) (sw 9706), where the sw 1021 virus has shown to be more pathogenic in mice. By using reverse genetics, we swapped the PB1 genes of these two viruses. Similar to the sw 9706 virus, chimeric sw 1021 virus carrying the sw 9706 PB1 gene was not virulent in mice. In contrast, replacement of the PB1 gene of the sw 9706 virus by that from sw 1021 virus resulted in increased pathogenicity. Our study demonstrated that differences in virulence of swine influenza virus subtype H1N2 are attributed at least in part to the PB1 segment. Copyright © 2014 Elsevier B.V. All rights reserved.

Simultaneous infection of pigs and people with triple-reassortant swine influenza virus H1N1 at a U.S. county fair.

PubMed

Killian, M L; Swenson, S L; Vincent, A L; Landgraf, J G; Shu, B; Lindstrom, S; Xu, X; Klimov, A; Zhang, Y; Bowman, A S

2013-05-01

Influenza-like illness was noted in people and pigs in attendance at an Ohio county fair in August 2007. The morbidity rate in swine approached 100% within 1-2 days of initial clinical signs being recognized, and approximately two dozen people developed influenza-like illness. Triple-reassortant swine H1N1 influenza viruses were identified in both pigs and people at the fair. The identified viruses (A/Sw/OH/511445/2007, A/Ohio/01/2007, and A/Ohio/02/2007) were similar to H1N1 swine influenza viruses currently found in the U.S. swine population. This case illustrates the possibility of transmission of swine influenza in settings where there is close human/swine interaction. © 2012 Blackwell Verlag GmbH.

Safety and efficacy of a novel live attenuated influenza vaccine against pandemic H1N1 in swine

USDA-ARS?s Scientific Manuscript database

On June 11, 2009 the World Health Organization (WHO) declared that the outbreaks caused by novel swine-origin influenza A (H1N1) virus had reached pandemic proportions. The pandemic H1N1 (H1N1pdm) is the predominant influenza strain in the human population. It has also crossed the species barriers a...

Reassortment between swine H3N2 and 2009 pandemic H1N1 in the United States resulted in influenza A viruses with diverse genetic constellations with variable virulence in pigs

USDA-ARS?s Scientific Manuscript database

Repeated spillovers of the H1N1 pandemic virus (H1N1pdm09) from humans to pigs resulted in substantial evolution of swine influenza viruses, contributing to the genetic and antigenic diversity of influenza A virus (IAV) currently circulating in swine. The reassortment with endemic swine viruses and ...

The first Swedish H1N2 swine influenza virus isolate represents an uncommon reassortant.

PubMed

Bálint, Adám; Metreveli, Giorgi; Widén, Frederik; Zohari, Siamak; Berg, Mikael; Isaksson, Mats; Renström, Lena Hm; Wallgren, Per; Belák, Sándor; Segall, Thomas; Kiss, István

2009-10-28

The European swine influenza viruses (SIVs) show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority of the European H1N2 swine influenza viruses described so far possess haemagglutinin (HA) of the human-like H1N2 SIV viruses and the neuraminidase (NA) of either the European H1N2 or H3N2 SIV-like viruses. The Swedish isolate has an avian-like SIV HA and a H3N2 SIV-like NA, which is phylogenetically more closely related to H3N2 SIV NAs from isolates collected in the early '80s than to the NA of H3N2 origin of the H1N2 viruses isolated during the last decade, as depicted by some German strains, indicative of independent acquisition of the NA genes for these two types of reassortants. The internal genes proved to be entirely of avian-like SIV H1N1 origin. The prevalence of this SIV variant in pig populations needs to be determined, as well as the suitability of the routinely used laboratory reagents to analyze this strain.The description of this H1N2 SIV adds further information to influenza epidemiology and supports the necessity of surveillance for influenza viruses in pigs.

Treatment and Prevention of Pandemic H1N1 Influenza.

PubMed

Rewar, Suresh; Mirdha, Dashrath; Rewar, Prahlad

2015-01-01

Swine influenza is a respiratory infection common to pigs worldwide caused by type A influenza viruses, principally subtypes H1N1, H1N2, H2N1, H3N1, H3N2, and H2N3. Swine influenza viruses also can cause moderate to severe illness in humans and affect persons of all age groups. People in close contact with swine are at especially high risk. Until recently, epidemiological study of influenza was limited to resource-rich countries. The World Health Organization declared an H1N1 pandemic on June 11, 2009, after more than 70 countries reported 30,000 cases of H1N1 infection. In 2015, incidence of swine influenza increased substantially to reach a 5-year high. In India in 2015, 10,000 cases of swine influenza were reported with 774 deaths. The Centers for Disease Control and Prevention recommend real-time polymerase chain reaction as the method of choice for diagnosing H1N1. Antiviral drugs are the mainstay of clinical treatment of swine influenza and can make the illness milder and enable the patient to feel better faster. Antiviral drugs are most effective when they are started within the first 48 hours after the clinical signs begin, although they also may be used in severe or high-risk cases first seen after this time. The Centers for Disease Control and Prevention recommends use of oseltamivir (Tamiflu, Genentech) or zanamivir (Relenza, GlaxoSmithKline). Prevention of swine influenza has 3 components: prevention in swine, prevention of transmission to humans, and prevention of its spread among humans. Because of limited treatment options, high risk for secondary infection, and frequent need for intensive care of individuals with H1N1 pneumonia, environmental control, including vaccination of high-risk populations and public education are critical to control of swine influenza out breaks. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Genetic characterization of H1N2 swine influenza virus isolated in China and its pathogenesis and inflammatory responses in mice.

PubMed

Zhang, Yan; Wang, Nan; Cao, Jiyue; Chen, Huanchun; Jin, Meilin; Zhou, Hongbo

2013-09-01

In 2009, two H1N2 influenza viruses were isolated from trachea swabs of pigs in Hubei in China. We compared these sequences with the other 18 complete genome sequences of swine H1N2 isolates from China during 2004 to 2010 and undertook extensive analysis of their evolutionary patterns. Six different genotypes - two reassortants between triple reassortant (TR) H3N2 and classical swine (CS) H1N1 virus, three reassortants between TR H1N2, Eurasian avian-like H1N1 swine virus and H9N2 swine virus, and one reassortant between H1N1, H3N2 human virus and CS H1N1 virus - were observed in these 20 swine H1N2 isolates. The TR H1N2 swine virus is the predominant genotype, and the two Hubei H1N2 isolates were located in this cluster. We also used a mouse model to examine the pathogenesis and inflammatory responses of the two isolates. The isolates replicated efficiently in the lung, and exhibited a strong inflammatory response, serious pathological changes and mortality in infected mice. Given the role that swine can play as putative "genetic mixing vessels" and the observed transmission of TR H1N2 in ferrets, H1N2 influenza surveillance in pigs should be increased to minimize the potential threat to public health.

Avian influenza A (H5N1) virus antibodies in pigs and residents of swine farms, southern China.

PubMed

Cao, Nan; Zhu, Wanjun; Chen, Ye; Tan, Likai; Zhou, Pei; Cao, Zhenpeng; Ke, Changwen; Li, Yugu; Wu, Jie; Qi, Wenbao; Jiao, Peirong; Zhang, Guihong

2013-12-01

Since 1997, the H5 avian influenza viruses (AIVs) circulating in China have become an international concern. Clade 2.3.2 of H5N1 AIVs is genetically distinct from the viruses isolated before 2007 and antigenically different from the vaccine strains widely used in China. Swine farms in rural China are thought to play an important role in AIVs ecology. A seroepidemiological study was undertaken among swine farm residents and pigs to understand the prevalence of antibodies against H5N1 AIVs in southern China. During the period March 24, 2008 to December 25, 2012,serum samples were collected from 1606 swine farm residents on 40 swine farms in southern China. A total of 1980 pigs' serum samples were collected in the same swine farms where swine workers' serum samples were collected from March 2009 to March 2013. For a control group, 104 serum samples were collected from healthy city residents in Nanchang. All the serum samples were collected to perform hemagglutination inhibition (HI) and (neutralization) NT assays to investigate the prevalence of H5N1 AIV infections in southern China. Sixteen human samples were positive by HI assay and 10 of these were also positive by NT assay against H5N1. No serum samples from human control and pigs were HI positive for H5N1 AIV. Our results demonstrate minimal transmission H5N1 AIV from birds to pigs in the swine farms studied and the risk of poultry-to-human and poultry-to-pig transmission for at least clades 2.3.2 seemed very low. This study provides the first data regarding antibodies against H5N1 AIV in humans and pigs on swine farms in China. The findings of this study can serve as a baseline for additional serologic studies to assess transmission of H5N1 viruses between avian species, pigs and swine workers. Copyright © 2013 Elsevier B.V. All rights reserved.

Isolation and genetic characterization of avian-like H1N1 and novel ressortant H1N2 influenza viruses from pigs in China.

PubMed

Yu, Hai; Zhang, Peng-Chao; Zhou, Yan-Jun; Li, Guo-Xin; Pan, Jie; Yan, Li-Ping; Shi, Xiao-Xiao; Liu, Hui-Li; Tong, Guang-Zhi

2009-08-21

As pigs are susceptible to both human and avian influenza viruses, they have been proposed to be intermediate hosts or mixing vessels for the generation of pandemic influenza viruses through reassortment or adaptation to the mammalian host. In this study, we reported avian-like H1N1 and novel ressortant H1N2 influenza viruses from pigs in China. Homology and phylogenetic analyses showed that the H1N1 virus (A/swine/Zhejiang/1/07) was closely to avian-like H1N1 viruses and seemed to be derived from the European swine H1N1 viruses, which was for the first time reported in China; and the two H1N2 viruses (A/swine/Shanghai/1/07 and A/swine/Guangxi/13/06) were novel ressortant H1N2 influenza viruses containing genes from the classical swine (HA, NP, M and NS), human (NA and PB1) and avian (PB2 and PA) lineages, which indicted that the reassortment among human, avian, and swine influenza viruses had taken place in pigs in China and resulted in the generation of new viruses. The isolation of avian-like H1N1 influenza virus originated from the European swine H1N1 viruses, especially the emergence of two novel ressortant H1N2 influenza viruses provides further evidence that pigs serve as intermediate hosts or "mixing vessels", and swine influenza virus surveillance in China should be given a high priority.

Evaluation of the Cepheid Xpert Flu Assay for rapid identification and differentiation of influenza A, influenza A 2009 H1N1, and influenza B viruses.

PubMed

Novak-Weekley, S M; Marlowe, E M; Poulter, M; Dwyer, D; Speers, D; Rawlinson, W; Baleriola, C; Robinson, C C

2012-05-01

The Xpert Flu Assay cartridge is a next-generation nucleic acid amplification system that provides multiplexed PCR detection of the influenza A, influenza A 2009 H1N1, and influenza B viruses in approximately 70 min with minimal hands-on time. Six laboratories participated in a clinical trial comparing the results of the new Cepheid Xpert Flu Assay to those of culture or real-time PCR with archived and prospectively collected nasal aspirate-wash (NA-W) specimens and nasopharyngeal (NP) swabs from children and adults. Discrepant results were resolved by DNA sequence analysis. After discrepant-result analysis, the sensitivities of the Xpert Flu Assay for prospective NA-W specimens containing the influenza A, influenza A 2009 H1N1, and influenza B viruses compared to those of culture were 90.0%, 100%, and 100%, respectively, while the sensitivities of the assay for prospective NP swabs compared to those of culture were 100%, 100%, and 100%, respectively. The sensitivities of the Xpert Flu Assay for archived NA-W specimens compared to those of Gen-Probe ProFlu+ PCR for the influenza A, influenza A 2009 H1N1, and influenza B viruses were 99.4%, 98.4%, and 100%, respectively, while the sensitivities of the Xpert Flu Assay for archived NP swabs compared to those of ProFlu+ were 98.1%, 100%, and 93.8%, respectively. The sensitivities of the Xpert Flu Assay with archived NP specimens compared to those of culture for the three targets were 97.5%, 100%, and 93.8%, respectively. We conclude that the Cepheid Xpert Flu Assay is an accurate and rapid method that is suitable for on-demand testing for influenza viral infection.

Vaccination with NS1-truncated H3N2 swine influenza virus primes T cells and confers cross-protection against an H1N1 heterosubtypic challenge in pigs

USDA-ARS?s Scientific Manuscript database

The diversity of contemporary swine influenza virus (SIV) strains impedes effective immunization of swine herds. Mucosally delivered, attenuated virus vaccines are one approach with potential to provide broad cross-protection. Reverse genetics-derived H3N2 SIV virus with truncated NS1 (NS1delta126 T...

Multiplex RT-PCR assay for differentiating European swine influenza virus subtypes H1N1, H1N2 and H3N2.

PubMed

Chiapponi, Chiara; Moreno, Ana; Barbieri, Ilaria; Merenda, Marianna; Foni, Emanuela

2012-09-01

In Europe, three major swine influenza viral (SIV) subtypes (H1N1, H1N2 and H3N2) have been isolated in pigs. Developing a test that is able to detect and identify the subtype of the circulating strain rapidly during an outbreak of respiratory disease in the pig population is of essential importance. This study describes two multiplex RT-PCRs which distinguish the haemagglutinin (HA) gene and the neuraminidase (NA) gene of the three major subtypes of SIV circulating in Europe. The HA PCR was able to identify the lineage (avian or human) of the HA of H1 subtypes. The analytical sensitivity of the test, considered to be unique, was assessed using three reference viruses. The detection limit corresponded to 1×10(-1) TCID(50)/200μl for avian-like H1N1, 1×10(0) TCID(50)/200μl for human-like H1N2 and 1×10(1) TCID(50)/200μl for H3N2 SIV. The multiplex RT-PCR was first carried out on a collection of 70 isolated viruses showing 100% specificity and then on clinical samples, from which viruses had previously been isolated, resulting in an 89% positive specificity of the viral subtype. Finally, the test was able to identify the viral subtype correctly in 56% of influenza A positive samples, from which SIV had not been isolated previously. It was also possible to identify mixed viral infections and the circulation of a reassortant strain before performing genomic studies. Copyright © 2012 Elsevier B.V. All rights reserved.

Adaptive evolution during the establishment of European avian-like H1N1 influenza A virus in swine.

PubMed

Joseph, Udayan; Vijaykrishna, Dhanasekaran; Smith, Gavin J D; Su, Yvonne C F

2018-04-01

An H1N1 subtype influenza A virus with all eight gene segments derived from wild birds (including mallards), ducks and chickens, caused severe disease outbreaks in swine populations in Europe beginning in 1979 and successfully adapted to form the European avian-like swine (EA-swine) influenza lineage. Genes of the EA-swine lineage that are clearly segregated from its closest avian relatives continue to circulate in swine populations globally and represent a unique opportunity to study the adaptive process of an avian-to-mammalian cross-species transmission. Here, we used a relaxed molecular clock model to test whether the EA-swine virus originated through the introduction of a single avian ancestor as an entire genome, followed by an analysis of host-specific selection pressures among different gene segments. Our data indicated independent introduction of gene segments via transmission of avian viruses into swine followed by reassortment events that occurred at least 1-4 years prior to the EA-swine outbreak. All EA-swine gene segments exhibit greater selection pressure than avian viruses, reflecting both adaptive pressures and relaxed selective constraints that are associated with host switching. Notably, we identified key amino acid mutations in the viral surface proteins (H1 and N1) that play a role in adaptation to new hosts. Following the establishment of EA-swine lineage, we observed an increased frequency of intrasubtype reassortment of segments compared to the earlier strains that has been associated with adaptive amino acid replacements, disease severity and vaccine escape. Taken together, our study provides key insights into the adaptive changes in viral genomes following the transmission of avian influenza viruses to swine and the early establishment of the EA-swine lineage.

Transmission dynamics of pandemic influenza A(H1N1)pdm09 virus in humans and swine in backyard farms in Tumbes, Peru.

PubMed

Tinoco, Yeny O; Montgomery, Joel M; Kasper, Mathew R; Nelson, Martha I; Razuri, Hugo; Guezala, Maria C; Azziz-Baumgartner, Eduardo; Widdowson, Marc-Alain; Barnes, John; Gilman, Robert H; Bausch, Daniel G; Gonzalez, Armando E

2016-01-01

We aimed to determine the frequency of pH1N1 transmission between humans and swine on backyard farms in Tumbes, Peru. Two-year serial cross-sectional study comprising four sampling periods: March 2009 (pre-pandemic), October 2009 (peak of the pandemic in Peru), April 2010 (1st post-pandemic period), and October 2011 (2nd post-pandemic period). Backyard swine serum, tracheal swabs, and lung sample were collected during each sampling period. We assessed current and past pH1N1 infection in swine through serological testing, virus culture, and RT-PCR and compared the results with human incidence data from a population-based active surveillance cohort study in Peru. Among 1303 swine sampled, the antibody prevalence to pH1N1 was 0% pre-pandemic, 8% at the peak of the human pandemic (October 2009), and 24% in April 2010 and 1% in October 2011 (post-pandemic sampling periods). Trends in swine seropositivity paralleled those seen in humans in Tumbes. The pH1N1 virus was isolated from three pigs during the peak of the pandemic. Phylogenetic analysis revealed that these viruses likely represent two separate human-to-swine transmission events in backyard farm settings. Our findings suggest that human-to-swine pH1N1 transmission occurred during the pandemic among backyard farms in Peru, emphasizing the importance of interspecies transmission in backyard pig populations. Continued surveillance for influenza viruses in backyard farms is warranted. © 2015 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

A rapid method for assessing social versus independent interest in health issues: a case study of 'bird flu' and 'swine flu'.

PubMed

Bentley, R Alexander; Ormerod, Paul

2010-08-01

Effective communication strategies regarding health issues are affected by the way in which the public obtain their knowledge, particularly whether people become interested independently, or through their social networks. This is often investigated through localized ethnography or surveys. In rapidly-evolving situations, however, there may also be a need for swift, case-specific assessment as a guide to initial strategy development. With this aim, we analyze real-time online data, provided by the new 'Google Trends' tool, concerning Internet search frequency for health-related issues. To these data we apply a simple model to characterise the effective degree of social transmission versus decisions made individually. As case examples, we explore two rapidly-evolved issues, namely the world-wide interest in avian influenza, or 'bird flu', in 2005, and in H1N1, or 'swine flu', from late April to early May 2009. The 2005 'bird flu' scare demonstrated almost pure imitation for two months initially, followed by a spike of independent decision that corresponded with an announcement by US president George Bush. For 'swine flu' in 2009, imitation was the more prevalent throughout. Overall, the results show how interest in health scares can spread primarily by social means, and that engaging more independent decisions at the population scale may require a dramatic announcement to push a populace over the 'tipping point'. Copyright 2010 Elsevier Ltd. All rights reserved.

Modeling of the influence of humidity on H1N1 flu in China

NASA Astrophysics Data System (ADS)

PEI, Y.; Tian, H.; Xu, B.

2015-12-01

In 2009, a heavy Flu hit the whole world. It was caused by the virus H1N1. The influenza first broke out in Mexico in March and the United States in April, 2009. The World Health Organization (WHO) announced that the H1N1 influenza became pandemic, alert to a warning phase of six. By the end of 2011, 181302 H1N1 cases were reported in mainland China. To improve our understanding on the impact of environmental factors on the disease transmission, we constructed an SIR (Susceptible - Infectious - Recovered) model incorporating environmental factors. It was found that the absolute humidity was a dominant environmental factor. The study interpolated the humidity data monitored with 340 weather stations from 1951 to 2011 in mainland China. First, the break point of the trend for the absolutely humidity was detected by the BFAST (Break For Additive Season and Trend) method. Then, the SIR model with and without the absolutely humidity incorporated in the model was built and tested. Finally, the results with the two scenarios were compared. Results indicate that lower absolutely humidity may promote the transmission of the H1N1 cases. The calculated basic reproductive number ranges from 1.65 to 3.66 with a changing absolute humidity. This is consistent with the former study result with basic reproductive number ranging from 2.03 to 4.18. The average recovery duration was estimated to be 5.7 days. The average duration to get immunity from the influenza is 399.02 days. A risk map is also produced to illustrate the model results.

H1N1 viral proteome peptide microarray predicts individuals at risk for H1N1 infection and segregates infection versus Pandemrix® vaccination

PubMed Central

Ambati, Aditya; Valentini, Davide; Montomoli, Emanuele; Lapini, Guilia; Biuso, Fabrizio; Wenschuh, Holger; Magalhaes, Isabelle; Maeurer, Markus

2015-01-01

A high content peptide microarray containing the entire influenza A virus [A/California/08/2009(H1N1)] proteome and haemagglutinin proteins from 12 other influenza A subtypes, including the haemagglutinin from the [A/South Carolina/1/1918(H1N1)] strain, was used to gauge serum IgG epitope signatures before and after Pandemrix® vaccination or H1N1 infection in a Swedish cohort during the pandemic influenza season 2009. A very narrow pattern of pandemic flu-specific IgG epitope recognition was observed in the serum from individuals who later contracted H1N1 infection. Moreover, the pandemic influenza infection generated IgG reactivity to two adjacent epitopes of the neuraminidase protein. The differential serum IgG recognition was focused on haemagglutinin 1 (H1) and restricted to classical antigenic sites (Cb) in both the vaccinated controls and individuals with flu infections. We further identified a novel epitope VEPGDKITFEATGNL on the Ca antigenic site (251–265) of the pandemic flu haemagglutinin, which was exclusively recognized in serum from individuals with previous vaccinations and never in serum from individuals with H1N1 infection (confirmed by RNA PCR analysis from nasal swabs). This epitope was mapped to the receptor-binding domain of the influenza haemagglutinin and could serve as a correlate of immune protection in the context of pandemic flu. The study shows that unbiased epitope mapping using peptide microarray technology leads to the identification of biologically and clinically relevant target structures. Most significantly an H1N1 infection induced a different footprint of IgG epitope recognition patterns compared with the pandemic H1N1 vaccine. PMID:25639813

Identification of reassortant pandemic H1N1 influenza virus in Korean pigs.

PubMed

Han, Jae Yeon; Park, Sung Jun; Kim, Hye Kwon; Rho, Semi; Nguyen, Giap Van; Song, Daesub; Kang, Bo Kyu; Moon, Hyung Jun; Yeom, Min Joo; Park, Bong Kyun

2012-05-01

Since the 2009 pandemic human H1N1 influenza A virus emerged in April 2009, novel reassortant strains have been identified throughout the world. This paper describes the detection and isolation of reassortant strains associated with human pandemic influenza H1N1 and swine influenza H1N2 (SIV) viruses in swine populations in South Korea. Two influenza H1N2 reassortants were detected, and subtyped by PCR. The strains were isolated using Madin- Darby canine kidney (MDCK) cells, and genetically characterized by phylogenetic analysis for genetic diversity. They consisted of human, avian, and swine virus genes that were originated from the 2009 pandemic H1N1 virus and a neuraminidase (NA) gene from H1N2 SIV previously isolated in North America. This identification of reassortment events in swine farms raises concern that reassortant strains may continuously circulate within swine populations, calling for the further study and surveillance of pandemic H1N1 among swine.

Colds and the flu - what to ask your doctor - adult

MedlinePlus

... to ask your doctor about colds and the flu - adult; Influenza - what to ask your doctor - adult; Upper respiratory ... what to ask your doctor - adult; H1N1 (Swine) flu - what to ask your doctor - adult

Pre-infection of pigs with Mycoplasma hyopneumoniae induces oxidative stress that influences outcomes of a subsequent infection with a swine influenza virus of H1N1 subtype.

PubMed

Deblanc, C; Robert, F; Pinard, T; Gorin, S; Quéguiner, S; Gautier-Bouchardon, A V; Ferré, S; Garraud, J M; Cariolet, R; Brack, M; Simon, G

2013-03-23

The severity of swine influenza is highly variable and can be exacerbated by many factors, such as a pre-infection of pigs with Mycoplasma hyopneumoniae (Mhp). The aim of this study was to investigate the oxidative stress induced by Mhp and the impact of this stress on the evolution of an infection with the European avian-like swine H1N1 influenza virus. Two experimental trials (E1 and E2), which differed only by the feed delivered to the animals, were conducted on SPF pigs. In each trial, one group of nine 6-week-old pigs was inoculated intra-tracheally with Mhp and H1N1 at 21 days intervals and a mock-infected group (8 pigs) was included. Clinical signs were observed, blood samples were collected throughout the study and pathogens were detected in nasal swabs and lung tissues. Results indicated that Mhp infection induced an oxidative stress in E1 and E2, but its level was more important in E2 than in E1 three weeks post-Mhp inoculation, before H1N1 infection. In both trials, a strong inflammatory response and a response to the oxidative stress previously induced by Mhp appeared after H1N1 infection. However, the severity of influenza disease was significantly more marked in E2 as compared to E1, as revealed by prolonged hyperthermia, stronger reduction in mean daily weight gain and earlier viral shedding. These results suggested that severity of flu syndrome and reduction in animal performance may vary depending on the level of oxidative stress at the moment of the influenza infection, and that host responses could be influenced by the feed. Copyright © 2012 Elsevier B.V. All rights reserved.

Colds and the flu - what to ask your doctor - child

MedlinePlus

... to ask your doctor about colds and the flu - child; Influenza - what to ask your doctor - child; Upper respiratory ... URI - what to ask your doctor - child; Swine flu (H1N1) - what to ask your doctor - child

Genetic characterization of H1N2 influenza a virus isolated from sick pigs in Southern China in 2010.

PubMed

Kong, Wei Li; Huang, Liang Zong; Qi, Hai Tao; Cao, Nan; Zhang, Liang Quan; Wang, Heng; Guan, Shang Song; Qi, Wen Bao; Jiao, Pei Rong; Liao, Ming; Zhang, Gui Hong

2011-10-13

In China H3N2 and H1N1 swine influenza viruses have been circulating for many years. In January 2010, before swine were infected with foot and mouth disease in Guangdong, some pigs have shown flu-like symptoms: cough, sneeze, runny nose and fever. We collected the nasopharyngeal swab of all sick pigs as much as possible. One subtype H1N2 influenza viruses were isolated from the pig population. The complete genome of one isolate, designated A/swine/Guangdong/1/2010(H1N2), was sequenced and compared with sequences available in GenBank. The nucleotide sequences of all eight viral RNA segments were determined, and then phylogenetic analysis was performed using the neighbor-joining method. HA, NP, M and NS were shown to be closely to swine origin. PB2 and PA were close to avian origin, but NA and PB1were close to human origin. It is a result of a multiple reassortment event. In conclusion, our finding provides further evidence about the interspecies transmission of avian influenza viruses to pigs and emphasizes the importance of reinforcing swine influenza virus (SIV) surveillance, especially before the emergence of highly pathogenic FMDs in pigs in Guangdong.

Sensitivity of influenza rapid diagnostic tests to H5N1 and 2009 pandemic H1N1 viruses.

PubMed

Sakai-Tagawa, Yuko; Ozawa, Makoto; Tamura, Daisuke; Le, Mai thi Quynh; Nidom, Chairul A; Sugaya, Norio; Kawaoka, Yoshihiro

2010-08-01

Simple and rapid diagnosis of influenza is useful for making treatment decisions in the clinical setting. Although many influenza rapid diagnostic tests (IRDTs) are available for the detection of seasonal influenza virus infections, their sensitivity for other viruses, such as H5N1 viruses and the recently emerged swine origin pandemic (H1N1) 2009 virus, remains largely unknown. Here, we examined the sensitivity of 20 IRDTs to various influenza virus strains, including H5N1 and 2009 pandemic H1N1 viruses. Our results indicate that the detection sensitivity to swine origin H1N1 viruses varies widely among IRDTs, with some tests lacking sufficient sensitivity to detect the early stages of infection when the virus load is low.

Respiratory failure presenting in H1N1 influenza with Legionnaires disease: two case reports

PubMed Central

2011-01-01

Introduction Media sensationalism on the H1N1 outbreak may have influenced decisional processes and clinical diagnosis. Case Presentation We report two cases of patients who presented in 2009 with coexisting H1N1 virus and Legionella infections: a 69-year-old Caucasian man and a 71-year-old Caucasian woman. In our cases all the signs and symptoms, including vomiting, progressive respiratory disease leading to respiratory failure, refractory hypoxemia, leukopenia, lymphopenia, thrombocytopenia, and elevated levels of creatine kinase and hepatic aminotransferases, were consistent with critical illness due to 2009 H1N1 virus infection. Other infectious disorders may mimic H1N1 viral infection especially Legionnaires' disease. Because the swine flu H1N1 pandemic occurred in Autumn in Italy, Legionnaires disease was to be highly suspected since the peak incidence usually occurs in early fall. We do think that our immediate suspicion of Legionella infection based on clinical history and X-ray abnormalities was fundamental for a successful resolution. Conclusion Our two case reports suggest that patients with H1N1 should be screened for Legionella, which is not currently common practice. This is particularly important since the signs and symptoms of both infections are similar. PMID:22018019

Characterization of H1N1 swine influenza viruses circulating in Canadian pigs in 2009.

PubMed

Nfon, Charles K; Berhane, Yohannes; Hisanaga, Tamiko; Zhang, Shunzhen; Handel, Katherine; Kehler, Helen; Labrecque, Olivia; Lewis, Nicola S; Vincent, Amy L; Copps, John; Alexandersen, Soren; Pasick, John

2011-09-01

The 2009 pandemic H1N1 (pH1N1), of apparent swine origin, may have evolved in pigs unnoticed because of insufficient surveillance. Consequently, the need for surveillance of influenza viruses circulating in pigs has received added attention. In this study we characterized H1N1 viruses isolated from Canadian pigs in 2009. Isolates from May 2009 were comprised of hemagglutinin and neuraminidase (NA) genes of classical SIV origin in combination with the North American triple-reassortant internal gene (TRIG) cassette, here termed contemporary SIV (conSIV) H1N1. These conSIV H1N1 viruses were contiguous with the North American αH1 cluster, which was distinct from the pH1N1 isolates that were antigenically more related to the γH1 cluster. After the initial isolation of pH1N1 from an Alberta pig farm in early May 2009, pH1N1 was found several times in Canadian pigs. These pH1N1 isolates were genetically and antigenically homogeneous. In addition, H1N1 viruses bearing seasonal human H1 and N1 genes together with the TRIG cassette and an NA encoding an oseltamivir-resistance marker were isolated from pigs. The NS gene of one of these seasonal human-like SIV (shSIV) H1N1 isolates was homologous to pH1N1 NS, implicating reassortment between the two strains. Antigenic cross-reactivity was observed between pH1N1 and conSIV but not with shSIV H1N1. In summary, although there was cocirculation of pH1N1 with conSIV and shSIV H1N1 in Canadian pigs after May 2009, there was no evidence supporting the presence of pH1N1 in pigs prior to May 2009. The possibility for further reassortants being generated exists and should be closely monitored.

[Influenza A/H5N1 virus outbreaks and prepardness to avert flu pandemic].

PubMed

Haque, A; Lucas, B; Hober, D

2007-01-01

This review emphasizes the need to improve the knowledge of the biology of H5N1 virus, a candidate for causing the next influenza pandemic. In-depth knowledge of mode of infection, mechanisms of pathogenesis and immune response will help in devising an efficient and practical control strategy against this flu virus. We have discussed limitations of currently available vaccines and proposed novel approaches for making better vaccines against H5N1 influenza virus. They include cell-culture system, reverse genetics, adjuvant development. Our review has also underscored the concept of therapeutic vaccine (anti-disease vaccine), which is aimed at diminishing 'cytokine storm' seen in acute respiratory distress syndrome and/or hemophagocytosis.

Characterization of an Artificial Swine-Origin Influenza Virus with the Same Gene Combination as H1N1/2009 Virus: A Genesis Clue of Pandemic Strain

PubMed Central

Pu, Juan; Fan, Lihong; Shi, Weimin; Hu, Yanxin; Yang, Jun; Xu, Qi; Wang, Jingjing; Hou, Dongjun; Ma, Guangpeng; Liu, Jinhua

2011-01-01

Pandemic H1N1/2009 influenza virus, derived from a reassortment of avian, human, and swine influenza viruses, possesses a unique gene segment combination that had not been detected previously in animal and human populations. Whether such a gene combination could result in the pathogenicity and transmission as H1N1/2009 virus remains unclear. In the present study, we used reverse genetics to construct a reassortant virus (rH1N1) with the same gene combination as H1N1/2009 virus (NA and M genes from a Eurasian avian-like H1N1 swine virus and another six genes from a North American triple-reassortant H1N2 swine virus). Characterization of rH1N1 in mice showed that this virus had higher replicability and pathogenicity than those of the seasonal human H1N1 and Eurasian avian-like swine H1N1 viruses, but was similar to the H1N1/2009 and triple-reassortant H1N2 viruses. Experiments performed on guinea pigs showed that rH1N1 was not transmissible, whereas pandemic H1N1/2009 displayed efficient transmissibility. To further determine which gene segment played a key role in transmissibility, we constructed a series of reassortants derived from rH1N1 and H1N1/2009 viruses. Direct contact transmission studies demonstrated that the HA and NS genes contributed to the transmission of H1N1/2009 virus. Second, the HA gene of H1N1/2009 virus, when combined with the H1N1/2009 NA gene, conferred efficient contact transmission among guinea pigs. The present results reveal that not only gene segment reassortment but also amino acid mutation were needed for the generation of the pandemic influenza virus. PMID:21799774

Characterization of an artificial swine-origin influenza virus with the same gene combination as H1N1/2009 virus: a genesis clue of pandemic strain.

PubMed

Zhao, Xueli; Sun, Yipeng; Pu, Juan; Fan, Lihong; Shi, Weimin; Hu, Yanxin; Yang, Jun; Xu, Qi; Wang, Jingjing; Hou, Dongjun; Ma, Guangpeng; Liu, Jinhua

2011-01-01

Pandemic H1N1/2009 influenza virus, derived from a reassortment of avian, human, and swine influenza viruses, possesses a unique gene segment combination that had not been detected previously in animal and human populations. Whether such a gene combination could result in the pathogenicity and transmission as H1N1/2009 virus remains unclear. In the present study, we used reverse genetics to construct a reassortant virus (rH1N1) with the same gene combination as H1N1/2009 virus (NA and M genes from a Eurasian avian-like H1N1 swine virus and another six genes from a North American triple-reassortant H1N2 swine virus). Characterization of rH1N1 in mice showed that this virus had higher replicability and pathogenicity than those of the seasonal human H1N1 and Eurasian avian-like swine H1N1 viruses, but was similar to the H1N1/2009 and triple-reassortant H1N2 viruses. Experiments performed on guinea pigs showed that rH1N1 was not transmissible, whereas pandemic H1N1/2009 displayed efficient transmissibility. To further determine which gene segment played a key role in transmissibility, we constructed a series of reassortants derived from rH1N1 and H1N1/2009 viruses. Direct contact transmission studies demonstrated that the HA and NS genes contributed to the transmission of H1N1/2009 virus. Second, the HA gene of H1N1/2009 virus, when combined with the H1N1/2009 NA gene, conferred efficient contact transmission among guinea pigs. The present results reveal that not only gene segment reassortment but also amino acid mutation were needed for the generation of the pandemic influenza virus.

Investigation of Pathogenesis of H1N1 Influenza Virus and Swine Streptococcus suis Serotype 2 Co-Infection in Pigs by Microarray Analysis

PubMed Central

Shi, Jian; Wang, Ruifang; Sun, Xin; Liu, Xiaokun; Zhao, Lianzhong; Jin, Meilin

2015-01-01

Swine influenza virus and Streptococcus suis are two important contributors to the porcine respiratory disease complex, and both have significant economic impacts. Clinically, influenza virus and Streptococcus suis co-infections in pigs are very common, which often contribute to severe pneumonia and can increase the mortality. However, the co-infection pathogenesis in pigs is unclear. In the present study, co-infection experiments were performed using swine H1N1 influenza virus and Streptococcus suis serotype 2 (SS2). The H1N1-SS2 co-infected pigs exhibited more severe clinical symptoms, serious pathological changes, and robust apoptosis of lungs at 6 days post-infection compared with separate H1N1 and SS2 infections. A comprehensive gene expression profiling using a microarray approach was performed to investigate the global host responses of swine lungs against the swine H1N1 infection, SS2 infection, co-infection, and phosphate-buffered saline control. Results showed 457, 411, and 844 differentially expressed genes in the H1N1, SS2, and H1N1-SS2 groups, respectively, compared with the control. Noticeably, genes associated with the immune, inflammatory, and apoptosis responses were highly overexpressed in the co-infected group. Pathway analysis indicated that the cytokine–cytokine receptor interactions, MAPK, toll-like receptor, complement and coagulation cascades, antigen processing and presentation, and apoptosis pathway were significantly regulated in the co-infected group. However, the genes related to these were less regulated in the separate H1N1 and SS2 infection groups. This observation suggested that a certain level of synergy was induced by H1N1 and SS2 co-infection with significantly stronger inflammatory and apoptosis responses, which may lead to more serious respiratory disease syndrome and pulmonary pathological lesion. PMID:25906258

Investigation of Pathogenesis of H1N1 Influenza Virus and Swine Streptococcus suis Serotype 2 Co-Infection in Pigs by Microarray Analysis.

PubMed

Lin, Xian; Huang, Canhui; Shi, Jian; Wang, Ruifang; Sun, Xin; Liu, Xiaokun; Zhao, Lianzhong; Jin, Meilin

2015-01-01

Swine influenza virus and Streptococcus suis are two important contributors to the porcine respiratory disease complex, and both have significant economic impacts. Clinically, influenza virus and Streptococcus suis co-infections in pigs are very common, which often contribute to severe pneumonia and can increase the mortality. However, the co-infection pathogenesis in pigs is unclear. In the present study, co-infection experiments were performed using swine H1N1 influenza virus and Streptococcus suis serotype 2 (SS2). The H1N1-SS2 co-infected pigs exhibited more severe clinical symptoms, serious pathological changes, and robust apoptosis of lungs at 6 days post-infection compared with separate H1N1 and SS2 infections. A comprehensive gene expression profiling using a microarray approach was performed to investigate the global host responses of swine lungs against the swine H1N1 infection, SS2 infection, co-infection, and phosphate-buffered saline control. Results showed 457, 411, and 844 differentially expressed genes in the H1N1, SS2, and H1N1-SS2 groups, respectively, compared with the control. Noticeably, genes associated with the immune, inflammatory, and apoptosis responses were highly overexpressed in the co-infected group. Pathway analysis indicated that the cytokine-cytokine receptor interactions, MAPK, toll-like receptor, complement and coagulation cascades, antigen processing and presentation, and apoptosis pathway were significantly regulated in the co-infected group. However, the genes related to these were less regulated in the separate H1N1 and SS2 infection groups. This observation suggested that a certain level of synergy was induced by H1N1 and SS2 co-infection with significantly stronger inflammatory and apoptosis responses, which may lead to more serious respiratory disease syndrome and pulmonary pathological lesion.

Fulminant fatal swine influenza (H1N1): Myocarditis, myocardial infarction, or severe influenza pneumonia?

PubMed

Cunha, Burke A; Syed, Uzma; Mickail, Nardeen

2010-01-01

The swine influenza (H1N1) pandemic began in Mexico and rapidly spread worldwide. As is the case with pandemic influenza A, the majority of early deaths have been in young healthy adults. The complications of pandemic H1N1 have been reported from several centers. Noteworthy has been the relative rarity of bacterial coinfection in bacterial pneumonia in hospitalized adults with H1N1 pneumonia. Simultaneous bacterial community-acquired pneumonia due to methicillin-sensitive Staphylococcus aureus or community-acquired methicillin resistant S. aureus and subsequent bacterial community-acquired pneumonia due to S. pneumoniae or Haemophilus influenzae have been reportedly rare (0.4%-4% of well-documented cases). Cardiac complications of H1N1 infection have been uncommon. Young healthy adults without a cardiac history who have H1N1 and chest pain usually have either acute myocardial infarction or acute myocarditis. Cardiac symptomatology with H1N1 often overshadows pulmonary manifestations, that is, influenza pneumonia. With H1N1 pneumonia, clinicians should be alert for otherwise unexplained tachycardia or chest pain that may represent acute myocardial infarction or myocarditis. We present a case of rapidly fatal H1N1 in a young adult treated with oseltamivir and peramivir. He was initially tachycardic, thought to represent myocarditis. He subsequently became hypotensive and expired. At autopsy there was cardiomegaly present but there were no signs of acute myocardial infarction or myocarditis. Pathologically, he died of severe H1N1 pneumonia and not bacterial pneumonia. Copyright © 2010 Elsevier Inc. All rights reserved.

Complete genome sequence of a novel influenza A H1N2 virus circulating in swine from Central Bajio region, Mexico.

PubMed

Sánchez-Betancourt, J I; Cervantes-Torres, J B; Saavedra-Montañez, M; Segura-Velázquez, R A

2017-12-01

The aim of this study was to perform the complete genome sequence of a swine influenza A H1N2 virus strain isolated from a pig in Guanajuato, México (A/swine/Mexico/GtoDMZC01/2014) and to report its seroprevalence in 86 counties at the Central Bajio zone. To understand the evolutionary dynamics of the isolate, we undertook a phylogenetic analysis of the eight gene segments. These data revealed that the isolated virus is a reassortant H1N2 subtype, as its genes are derived from human (HA, NP, PA) and swine (M, NA, PB1, PB2 and NS) influenza viruses. Pig serum samples were analysed by the hemagglutination inhibition test, using wild H1N2 and H3N2 strains (A/swine/México/Mex51/2010 [H3N2]) as antigen sources. Positive samples to the H1N2 subtype were processed using the field-isolated H1N1 subtype (A/swine/México/Ver37/2010 [H1N1]). Seroprevalence to the H1N2 subtype was 26.74% in the sampled counties, being Jalisco the state with highest seroprevalence to this subtype (35.30%). The results herein reported demonstrate that this new, previously unregistered influenza virus subtype in México that shows internal genes from other swine viral subtypes isolated in the past 5 years, along with human virus-originated genes, is widely distributed in this area of the country. © 2017 Blackwell Verlag GmbH.

Is it a policy crisis or it is a health crisis? The Egyptian context - Analysis of the Egyptian health policy for the H1N1 flu pandemic control

PubMed Central

Seef, Sameh; Jeppsson, Anders

2013-01-01

A new influenza virus that was first detected in people in April 2009, was initially referred to colloquially as “swine flu”, since it contained genes from swine, avian and human influenza viruses. It can, however, not be transmitted by eating pork or dealing with pigs. In Egypt, several hundred thousand pigs were killed in May, in spite of advice from global health authorities that such an action was unnecessary. Pigs are raised and consumed mainly by the Christian minority, which constitute some 10% of the population. Health Ministry estimated there were between 300,000-350,000 pigs in Egypt. This paper will analyze the Egyptian health policy for controlling the pandemic H1N1 flu, exploring its context, content, process, and actors. The analysis is based on the Leichter Context, which refers to systemic factors-political, economic and social, both national and international-that may have an effect on health policy, and is based on data collected from literature review and policy documents. The International health officials said the swine flu virus that has caused worldwide fear is not transmitted by pigs, and that pig slaughters do nothing to stop its spread. The WHO stopped using the term “swine flu” to avoid confusion. In Egypt, even the editor of a pro-government newspaper criticized the order to slaughter: “Killing (pigs) is not a solution, otherwise, we should kill the people, because the virus spreads through them,” wrote Abdullah Kamal of the daily Rose El-Youssef. The World Health organization also criticized the decision. The extinction of the Egyptian pigs is an example of how a health issue can be used to persecute a minority within a country. Although the current influenza has nothing whatsoever to do with pigs, the previous name of the epidemic was used as an argument to violate the rights of the Christian minority in Egypt. PMID:23565306

Comparative Pathogenesis of an Avian H5N2 and a Swine H1N1 Influenza Virus in Pigs

PubMed Central

De Vleeschauwer, Annebel; Atanasova, Kalina; Van Borm, Steven; van den Berg, Thierry; Rasmussen, Thomas Bruun; Uttenthal, Åse; Van Reeth, Kristien

2009-01-01

Pigs are considered intermediate hosts for the transmission of avian influenza viruses (AIVs) to humans but the basic organ pathogenesis of AIVs in pigs has been barely studied. We have used 42 four-week-old influenza naive pigs and two different inoculation routes (intranasal and intratracheal) to compare the pathogenesis of a low pathogenic (LP) H5N2 AIV with that of an H1N1 swine influenza virus. The respiratory tract and selected extra-respiratory tissues were examined for virus replication by titration, immunofluorescence and RT-PCR throughout the course of infection. Both viruses caused a productive infection of the entire respiratory tract and epithelial cells in the lungs were the major target. Compared to the swine virus, the AIV produced lower virus titers and fewer antigen positive cells at all levels of the respiratory tract. The respiratory part of the nasal mucosa in particular showed only rare AIV positive cells and this was associated with reduced nasal shedding of the avian compared to the swine virus. The titers and distribution of the AIV varied extremely between individual pigs and were strongly affected by the route of inoculation. Gross lung lesions and clinical signs were milder with the avian than with the swine virus, corresponding with lower viral loads in the lungs. The brainstem was the single extra-respiratory tissue found positive for virus and viral RNA with both viruses. Our data do not reject the theory of the pig as an intermediate host for AIVs, but they suggest that AIVs need to undergo genetic changes to establish full replication potential in pigs. From a biomedical perspective, experimental LP H5 AIV infection of pigs may be useful to examine heterologous protection provided by H5 vaccines or other immunization strategies, as well as for further studies on the molecular pathogenesis and neurotropism of AIVs in mammals. PMID:19684857

Public perceptions, anxiety, and behaviour change in relation to the swine flu outbreak: cross sectional telephone survey.

PubMed

Rubin, G James; Amlôt, Richard; Page, Lisa; Wessely, Simon

2009-07-02

To assess whether perceptions of the swine flu outbreak predicted changes in behaviour among members of the public in England, Scotland, and Wales. Cross sectional telephone survey using random digit dialling. Interviews by telephone between 8 and 12 May. 997 adults aged 18 or more who had heard of swine flu and spoke English. Recommended change in behaviour (increases in handwashing and surface cleaning or plans made with a "flu friend") and avoidance behaviours (engaged in one or more of six behaviours such as avoiding large crowds or public transport). 37.8% of participants (n=377) reported performing any recommended behaviour change "over the past four days . . . because of swine flu." 4.9% (n=49) had carried out any avoidance behaviour. Controlling for personal details and anxiety, recommended changes were associated with perceptions that swine flu is severe, that the risk of catching it is high risk, that the outbreak will continue for a long time, that the authorities can be trusted, that good information has been provided, that people can control their risk of catching swine flu, and that specific behaviours are effective in reducing the risk. Being uncertain about the outbreak and believing that the outbreak had been exaggerated were associated with a lower likelihood of change. The strongest predictor of behaviour change was ethnicity, with participants from ethnic minority groups being more likely to make recommended changes (odds ratio 3.2, 95% confidence interval 2.0 to 5.3) and carry out avoidance behaviours (4.1, 2.0 to 8.4). The results support efforts to inform the public about specific actions that can reduce the risks from swine flu and to communicate about the government's plans and resources. Tackling the perception that the outbreak has been "over-hyped" may be difficult but worthwhile. Additional research is required into differing reactions to the outbreak among ethnic groups.

Increased risk of A(H1N1)pdm09 influenza infection in UK pig industry workers compared to a general population cohort.

PubMed

Fragaszy, Ellen; Ishola, David A; Brown, Ian H; Enstone, Joanne; Nguyen-Van-Tam, Jonathan S; Simons, Robin; Tucker, Alexander W; Wieland, Barbara; Williamson, Susanna M; Hayward, Andrew C; Wood, James L N

2016-07-01

Pigs are mixing vessels for influenza viral reassortment, but the extent of influenza transmission between swine and humans is not well understood. To assess whether occupational exposure to pigs is a risk factor for human infection with human and swine-adapted influenza viruses. UK pig industry workers were frequency-matched on age, region, sampling month, and gender with a community-based comparison group from the Flu Watch study. HI assays quantified antibodies for swine and human A(H1) and A(H3) influenza viruses (titres ≥ 40 considered seropositive and indicative of infection). Virus-specific associations between seropositivity and occupational pig exposure were examined using multivariable regression models adjusted for vaccination. Pigs on the same farms were also tested for seropositivity. Forty-two percent of pigs were seropositive to A(H1N1)pdm09. Pig industry workers showed evidence of increased odds of A(H1N1)pdm09 seropositivity compared to the comparison group, albeit with wide confidence intervals (CIs), adjusted odds ratio after accounting for possible cross-reactivity with other swine A(H1) viruses (aOR) 25·3, 95% CI (1·4-536·3), P = 0·028. The results indicate that A(H1N1)pdm09 virus was common in UK pigs during the pandemic and subsequent period of human A(H1N1)pdm09 circulation, and occupational exposure to pigs was a risk factor for human infection. Influenza immunisation of pig industry workers may reduce transmission and the potential for virus reassortment. © 2015 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Influenza A(H1N1)pdm09 virus infection in Norwegian swine herds 2009/10: the risk of human to swine transmission.

PubMed

Grøntvedt, Carl Andreas; Er, Chiek; Gjerset, Britt; Hauge, Anna Germundsson; Brun, Edgar; Jørgensen, Anne; Lium, Bjørn; Framstad, Tore

2013-07-01

Influenza A viruses cause respiratory infection in humans and pigs, and some serotypes can be transmitted between these species. The emergence of influenza A(H1N1)pdm09 virus infections in the spring of 2009 quickly led to a worldwide pandemic in humans, with subsequent introduction of the virus to pig populations. Following a widespread infection in the human population in Norway, influenza A(H1N1)pdm09 virus was introduced to the influenza A naïve Norwegian pig population, and within a few months pigs in more than one third of Norwegian swine herds had antibodies against the virus. A cross-sectional study was performed on all swine nucleus and multiplier herds in Norway to analyze risk factors for introduction of infection, and the preventive effects of recommended biosecurity practices. A surveillance program provided information on infection status of the study herds, and a questionnaire was administered to all 118 nucleus and multiplier herds to collect information on herd variables. The surveillance program revealed that pigs in 42% of the herds had antibodies against influenza A(H1N1)pdm09 virus. The incidence of serologically positive pigs was similar in both multiplier herds (41%) and closed nucleus herds (43%). Multivariable logistic regression showed that presence of farm staff with influenza-like illness (ILI) (OR=4.15, CI 1.5-11.4, p=0.005) and herd size (OR=1.01, CI 1-1.02, p=0.009) were risk factors for infection. The rapid and widespread seroconversion for antibodies against influenza A(H1N1)pdm09 virus in the Norwegian pig population can be explained by the emergence of a novel virus that is readily transmitted between people and swine in a largely susceptible population of humans, and an entirely naïve population of pigs. Copyright © 2013 Elsevier B.V. All rights reserved.

Novel Reassortant Human-Like H3N2 and H3N1 Influenza A Viruses Detected in Pigs Are Virulent and Antigenically Distinct from Swine Viruses Endemic to the United States

PubMed Central

Rajão, Daniela S.; Gauger, Phillip C.; Anderson, Tavis K.; Lewis, Nicola S.; Abente, Eugenio J.; Killian, Mary Lea; Sutton, Troy C.; Zhang, Jianqiang

2015-01-01

ABSTRACT Human-like swine H3 influenza A viruses (IAV) were detected by the USDA surveillance system. We characterized two novel swine human-like H3N2 and H3N1 viruses with hemagglutinin (HA) genes similar to those in human seasonal H3 strains and internal genes closely related to those of 2009 H1N1 pandemic viruses. The H3N2 neuraminidase (NA) was of the contemporary human N2 lineage, while the H3N1 NA was of the classical swine N1 lineage. Both viruses were antigenically distant from swine H3 viruses that circulate in the United States and from swine vaccine strains and also showed antigenic drift from human seasonal H3N2 viruses. Their pathogenicity and transmission in pigs were compared to those of a human H3N2 virus with a common HA ancestry. Both swine human-like H3 viruses efficiently infected pigs and were transmitted to indirect contacts, whereas the human H3N2 virus did so much less efficiently. To evaluate the role of genes from the swine isolates in their pathogenesis, reverse genetics-generated reassortants between the swine human-like H3N1 virus and the seasonal human H3N2 virus were tested in pigs. The contribution of the gene segments to virulence was complex, with the swine HA and internal genes showing effects in vivo. The experimental infections indicate that these novel H3 viruses are virulent and can sustain onward transmission in pigs, and the naturally occurring mutations in the HA were associated with antigenic divergence from H3 IAV from humans and swine. Consequently, these viruses could have a significant impact on the swine industry if they were to cause more widespread outbreaks, and the potential risk of these emerging swine IAV to humans should be considered. IMPORTANCE Pigs are important hosts in the evolution of influenza A viruses (IAV). Human-to-swine transmissions of IAV have resulted in the circulation of reassortant viruses containing human-origin genes in pigs, greatly contributing to the diversity of IAV in swine worldwide

Novel Reassortant Human-Like H3N2 and H3N1 Influenza A Viruses Detected in Pigs Are Virulent and Antigenically Distinct from Swine Viruses Endemic to the United States.

PubMed

Rajão, Daniela S; Gauger, Phillip C; Anderson, Tavis K; Lewis, Nicola S; Abente, Eugenio J; Killian, Mary Lea; Perez, Daniel R; Sutton, Troy C; Zhang, Jianqiang; Vincent, Amy L

2015-11-01

Human-like swine H3 influenza A viruses (IAV) were detected by the USDA surveillance system. We characterized two novel swine human-like H3N2 and H3N1 viruses with hemagglutinin (HA) genes similar to those in human seasonal H3 strains and internal genes closely related to those of 2009 H1N1 pandemic viruses. The H3N2 neuraminidase (NA) was of the contemporary human N2 lineage, while the H3N1 NA was of the classical swine N1 lineage. Both viruses were antigenically distant from swine H3 viruses that circulate in the United States and from swine vaccine strains and also showed antigenic drift from human seasonal H3N2 viruses. Their pathogenicity and transmission in pigs were compared to those of a human H3N2 virus with a common HA ancestry. Both swine human-like H3 viruses efficiently infected pigs and were transmitted to indirect contacts, whereas the human H3N2 virus did so much less efficiently. To evaluate the role of genes from the swine isolates in their pathogenesis, reverse genetics-generated reassortants between the swine human-like H3N1 virus and the seasonal human H3N2 virus were tested in pigs. The contribution of the gene segments to virulence was complex, with the swine HA and internal genes showing effects in vivo. The experimental infections indicate that these novel H3 viruses are virulent and can sustain onward transmission in pigs, and the naturally occurring mutations in the HA were associated with antigenic divergence from H3 IAV from humans and swine. Consequently, these viruses could have a significant impact on the swine industry if they were to cause more widespread outbreaks, and the potential risk of these emerging swine IAV to humans should be considered. Pigs are important hosts in the evolution of influenza A viruses (IAV). Human-to-swine transmissions of IAV have resulted in the circulation of reassortant viruses containing human-origin genes in pigs, greatly contributing to the diversity of IAV in swine worldwide. New human-like H3N2

Association of swine influenza H1N1 pandemic virus (SIV-H1N1p) with porcine respiratory disease complex in sows from commercial pig farms in Colombia.

PubMed

Jiménez, Luisa Fernanda Mancipe; Ramírez Nieto, Gloria; Alfonso, Victor Vera; Correa, Jairo Jaime

2014-08-01

Porcine respiratory disease complex (PRDC) is a serious health problem that mainly affects growing and finishing pigs. PRDC is caused by a combination of viral and bacterial agents, such as porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus (SIV), Mycoplasma hyopneumoniae (Myh), Actinobacillus pleuropneumoniae (APP), Pasteurella multocida and Porcine circovirus 2 (PCV2). To characterize the specific role of swine influenza virus in PRDC presentation in Colombia, 11 farms from three major production regions in Colombia were examined in this study. Nasal swabs, bronchial lavage and lung tissue samples were obtained from animals displaying symptoms compatible with SIV. Isolation of SIV was performed in 9-day embryonated chicken eggs or Madin-Darby Canine Kidney (MDCK) cells. Positive isolates, identified via the hemagglutination inhibition test, were further analyzed using PCR. Overall, 7 of the 11 farms were positive for SIV. Notably, sequencing of the gene encoding the hemagglutinin (HA) protein led to grouping of strains into circulating viruses identified during the human outbreak of 2009, classified as pandemic H1N1-2009. Serum samples from 198 gilts and multiparous sows between 2008 and 2009 were obtained to determine antibody presence of APP, Myh, PCV2 and PRRSV in both SIV-H1N1p-negative and -positive farms, but higher levels were recorded for SIV-H1N1p-positive farms. Odds ratio (OR) and P values revealed statistically significant differences (p<0.05) in PRDC presentation in gilts and multiparous sows of farms positive for SIV-H1N1p. Our findings indicate that positive farms have increased risk of PRDC presentation, in particular, PCV2, APP and Myh.

Computer-aided assessment of pulmonary disease in novel swine-origin H1N1 influenza on CT

NASA Astrophysics Data System (ADS)

Yao, Jianhua; Dwyer, Andrew J.; Summers, Ronald M.; Mollura, Daniel J.

2011-03-01

The 2009 pandemic is a global outbreak of novel H1N1 influenza. Radiologic images can be used to assess the presence and severity of pulmonary infection. We develop a computer-aided assessment system to analyze the CT images from Swine-Origin Influenza A virus (S-OIV) novel H1N1 cases. The technique is based on the analysis of lung texture patterns and classification using a support vector machine (SVM). Pixel-wise tissue classification is computed from the SVM value. The method was validated on four H1N1 cases and ten normal cases. We demonstrated that the technique can detect regions of pulmonary abnormality in novel H1N1 patients and differentiate these regions from visually normal lung (area under the ROC curve is 0.993). This technique can also be applied to differentiate regions infected by different pulmonary diseases.

Seroprevalence of H1N1, H3N2 and H1N2 influenza viruses in pigs in seven European countries in 2002-2003.

PubMed

Van Reeth, Kristien; Brown, Ian H; Dürrwald, Ralf; Foni, Emanuela; Labarque, Geoffrey; Lenihan, Patrick; Maldonado, Jaime; Markowska-Daniel, Iwona; Pensaert, Maurice; Pospisil, Zdenek; Koch, Guus

2008-05-01

Avian-like H1N1 and human-like H3N2 swine influenza viruses (SIV) have been considered widespread among pigs in Western Europe since the 1980s, and a novel H1N2 reassortant with a human-like H1 emerged in the mid 1990s. This study, which was part of the EC-funded 'European Surveillance Network for Influenza in Pigs 1', aimed to determine the seroprevalence of the H1N2 virus in different European regions and to compare the relative prevalences of each SIV between regions. Laboratories from Belgium, the Czech Republic, Germany, Italy, Ireland, Poland and Spain participated in an international serosurvey. A total of 4190 sow sera from 651 farms were collected in 2002-2003 and examined in haemagglutination inhibition tests against H1N1, H3N2 and H1N2. In Belgium, Germany, Italy and Spain seroprevalence rates to each of the three SIV subtypes were high (> or =30% of the sows seropositive) to very high (> or =50%), except for a lower H1N2 seroprevalence rate in Italy (13.8%). Most sows in these countries with high pig populations had antibodies to two or three subtypes. In Ireland, the Czech Republic and Poland, where swine farming is less intensive, H1N1 was the dominant subtype (8.0-11.7% seropositives) and H1N2 and H3N2 antibodies were rare (0-4.2% seropositives). Thus, SIV of H1N1, H3N2 and H1N2 subtype are enzootic in swine producing regions of Western Europe. In Central Europe, SIV activity is low and the circulation of H3N2 and H1N2 remains to be confirmed. The evolution and epidemiology of SIV throughout Europe is being further monitored through a second 'European Surveillance Network for Influenza in Pigs'.

Co-infection of classic swine H1N1 influenza virus in pigs persistently infected with porcine rubulavirus.

PubMed

Rivera-Benitez, José Francisco; De la Luz-Armendáriz, Jazmín; Saavedra-Montañez, Manuel; Jasso-Escutia, Miguel Ángel; Sánchez-Betancourt, Ivan; Pérez-Torres, Armando; Reyes-Leyva, Julio; Hernández, Jesús; Martínez-Lara, Atalo; Ramírez-Mendoza, Humberto

2016-02-29

Porcine rubulavirus (PorPV) and swine influenza virus infection causes respiratory disease in pigs. PorPV persistent infection could facilitate the establishment of secondary infections. The aim of this study was to analyse the pathogenicity of classic swine H1N1 influenza virus (swH1N1) in growing pigs persistently infected with porcine rubulavirus. Conventional six-week-old pigs were intranasally inoculated with PorPV, swH1N1, or PorPV/swH1N1. A mock-infected group was included. The co-infection with swH1N1 was at 44 days post-infection (DPI), right after clinical signs of PorPV infection had stopped. The pigs of the co-infection group presented an increase of clinical signs compared to the simple infection groups. In all infected groups, the most recurrent lung lesion was hyperplasia of the bronchiolar-associated lymphoid tissue and interstitial pneumonia. By means of immunohistochemical evaluation it was possible to demonstrate the presence of the two viral agents infecting simultaneously the bronchiolar epithelium. Viral excretion of PorPV in nasal and oral fluid was recorded at 28 and 52 DPI, respectively. PorPV persisted in several samples from respiratory tissues (RT), secondary lymphoid organs (SLO), and bronchoalveolar lavage fluid (BALF). For swH1N1, the viral excretion in nasal fluids was significantly higher in single-infected swH1N1 pigs than in the co-infected group. However, the co-infection group exhibited an increase in the presence of swH1N1 in RT, SLO, and BALF at two days after co-infection. In conclusion, the results obtained confirm an increase in the clinical signs of infection, and PorPV was observed to impact the spread of swH1N1 in analysed tissues in the early stage of co-infection, although viral shedding was not enhanced. In the present study, the interaction of swH1N1 infection is demonstrated in pigs persistently infected with PorPV. Copyright © 2016 Elsevier B.V. All rights reserved.

Evidence of reassortment of pandemic H1N1 influenza virus in swine in Argentina: are we facing the expansion of potential epicenters of influenza emergence?

PubMed Central

Pereda, Ariel; Rimondi, Agustina; Cappuccio, Javier; Sanguinetti, Ramon; Angel, Matthew; Ye, Jianqiang; Sutton, Troy; Dibárbora, Marina; Olivera, Valeria; Craig, Maria I.; Quiroga, Maria; Machuca, Mariana; Ferrero, Andrea; Perfumo, Carlos; Perez, Daniel R.

2011-01-01

Please cite this paper as: Pereda et al. (2011) Evidence of reassortment of pandemic H1N1 influenza virus in swine in Argentina: are we facing the expansion of potential epicenters of influenza emergence? Influenza and Other Respiratory Viruses 5(6), 409–412. In this report, we describe the occurrence of two novel swine influenza viruses (SIVs) in pigs in Argentina. These viruses are the result of two independent reassortment events between the H1N1 pandemic influenza virus (H1N1pdm) and human‐like SIVs, showing the constant evolution of influenza viruses at the human–swine interface and the potential health risk of H1N1pdm as it appears to be maintained in the swine population. It must be noted that because of the lack of information regarding the circulation of SIVs in South America, we cannot discard the possibility that ancestors of the H1N1pdm or other SIVs have been present in this part of the world. More importantly, these findings suggest an ever‐expanding geographic range of potential epicenters of influenza emergence with public health risks. PMID:21668680

Swine Influenza Virus PA and Neuraminidase Gene Reassortment into Human H1N1 Influenza Virus Is Associated with an Altered Pathogenic Phenotype Linked to Increased MIP-2 Expression.

PubMed

Dlugolenski, Daniel; Jones, Les; Howerth, Elizabeth; Wentworth, David; Tompkins, S Mark; Tripp, Ralph A

2015-05-01

Swine are susceptible to infection by both avian and human influenza viruses, and this feature is thought to contribute to novel reassortant influenza viruses. In this study, the influenza virus reassortment rate in swine and human cells was determined. Coinfection of swine cells with 2009 pandemic H1N1 virus (huH1N1) and an endemic swine H1N2 (A/swine/Illinois/02860/09) virus (swH1N2) resulted in a 23% reassortment rate that was independent of α2,3- or α2,6-sialic acid distribution on the cells. The reassortants had altered pathogenic phenotypes linked to introduction of the swine virus PA and neuraminidase (NA) into huH1N1. In mice, the huH1N1 PA and NA mediated increased MIP-2 expression early postinfection, resulting in substantial pulmonary neutrophilia with enhanced lung pathology and disease. The findings support the notion that swine are a mixing vessel for influenza virus reassortants independent of sialic acid distribution. These results show the potential for continued reassortment of the 2009 pandemic H1N1 virus with endemic swine viruses and for reassortants to have increased pathogenicity linked to the swine virus NA and PA genes which are associated with increased pulmonary neutrophil trafficking that is related to MIP-2 expression. Influenza A viruses can change rapidly via reassortment to create a novel virus, and reassortment can result in possible pandemics. Reassortments among subtypes from avian and human viruses led to the 1957 (H2N2 subtype) and 1968 (H3N2 subtype) human influenza pandemics. Recent analyses of circulating isolates have shown that multiple genes can be recombined from human, avian, and swine influenza viruses, leading to triple reassortants. Understanding the factors that can affect influenza A virus reassortment is needed for the establishment of disease intervention strategies that may reduce or preclude pandemics. The findings from this study show that swine cells provide a mixing vessel for influenza virus reassortment

Swine Influenza Virus PA and Neuraminidase Gene Reassortment into Human H1N1 Influenza Virus Is Associated with an Altered Pathogenic Phenotype Linked to Increased MIP-2 Expression

PubMed Central

Dlugolenski, Daniel; Jones, Les; Howerth, Elizabeth; Wentworth, David; Tompkins, S. Mark

2015-01-01

ABSTRACT Swine are susceptible to infection by both avian and human influenza viruses, and this feature is thought to contribute to novel reassortant influenza viruses. In this study, the influenza virus reassortment rate in swine and human cells was determined. Coinfection of swine cells with 2009 pandemic H1N1 virus (huH1N1) and an endemic swine H1N2 (A/swine/Illinois/02860/09) virus (swH1N2) resulted in a 23% reassortment rate that was independent of α2,3- or α2,6-sialic acid distribution on the cells. The reassortants had altered pathogenic phenotypes linked to introduction of the swine virus PA and neuraminidase (NA) into huH1N1. In mice, the huH1N1 PA and NA mediated increased MIP-2 expression early postinfection, resulting in substantial pulmonary neutrophilia with enhanced lung pathology and disease. The findings support the notion that swine are a mixing vessel for influenza virus reassortants independent of sialic acid distribution. These results show the potential for continued reassortment of the 2009 pandemic H1N1 virus with endemic swine viruses and for reassortants to have increased pathogenicity linked to the swine virus NA and PA genes which are associated with increased pulmonary neutrophil trafficking that is related to MIP-2 expression. IMPORTANCE Influenza A viruses can change rapidly via reassortment to create a novel virus, and reassortment can result in possible pandemics. Reassortments among subtypes from avian and human viruses led to the 1957 (H2N2 subtype) and 1968 (H3N2 subtype) human influenza pandemics. Recent analyses of circulating isolates have shown that multiple genes can be recombined from human, avian, and swine influenza viruses, leading to triple reassortants. Understanding the factors that can affect influenza A virus reassortment is needed for the establishment of disease intervention strategies that may reduce or preclude pandemics. The findings from this study show that swine cells provide a mixing vessel for influenza

Performance of the Directigen EZ Flu A+B rapid influenza diagnostic test to detect pandemic influenza A/H1N1 2009.

PubMed

Boyanton, Bobby L; Almradi, Amro; Mehta, Tejal; Robinson-Dunn, Barbara

2014-04-01

The Directigen EZ Flu A+B rapid influenza diagnostic test, as compared to real-time reverse transcriptase polymerase chain reaction, demonstrated suboptimal performance to detect pandemic influenza A/H1N1 2009. Age- and viral load-stratified test sensitivity ranged from 33.3 to 84.6% and 0 to 100%, respectively. © 2013.

Development of a Plastic-Based Microfluidic Immunosensor Chip for Detection of H1N1 Influenza

PubMed Central

Lee, Kyoung G.; Lee, Tae Jae; Jeong, Soon Woo; Choi, Ho Woon; Heo, Nam Su; Park, Jung Youn; Park, Tae Jung; Lee, Seok Jae

2012-01-01

Lab-on-a-chip can provide convenient and accurate diagnosis tools. In this paper, a plastic-based microfluidic immunosensor chip for the diagnosis of swine flu (H1N1) was developed by immobilizing hemagglutinin antigen on a gold surface using a genetically engineered polypeptide. A fluorescent dye-labeled antibody (Ab) was used for quantifying the concentration of Ab in the immunosensor chip using a fluorescent technique. For increasing the detection efficiency and reducing the errors, three chambers and three microchannels were designed in one microfluidic chip. This protocol could be applied to the diagnosis of other infectious diseases in a microfluidic device. PMID:23112630

Swine flu and antibiotics.

PubMed

Barlow, Gavin D

2009-11-01

Health services worldwide are likely to be hard-pressed by swine flu-related illness in the months ahead. Secondary infections with Streptococcus pneumoniae, other streptococci (e.g. Streptococcus pyogenes), Haemophilus influenzae and Staphylococcus aureus are likely to be important causes of morbidity and mortality. The UK Department of Health recently published clinical pathways for the management of swine flu. Suggested severity criteria have not been validated in respiratory infection and are different from those previously published. Antibiotics are recommended for all patients assessed at hospital, regardless of severity of illness; cephalosporins or quinolones are suggested for inpatients with pneumonia. These recommendations will jeopardize recent decreases in Clostridium difficile-associated diarrhoea (CDAD) and methicillin-resistant S. aureus (MRSA) in UK hospitals. This article, written on behalf of the BSAC Council, considers these recommendations and provides alternative antibiotic regimens for a range of clinical scenarios.

Adjuvant effects of invariant NKT cell ligand potentiates the innate and adaptive immunity to an inactivated H1N1 swine influenza virus vaccine in pigs.

PubMed

Dwivedi, Varun; Manickam, Cordelia; Dhakal, Santosh; Binjawadagi, Basavaraj; Ouyang, Kang; Hiremath, Jagadish; Khatri, Mahesh; Hague, Jacquelyn Gervay; Lee, Chang Won; Renukaradhya, Gourapura J

2016-04-15

Pigs are considered as the source of some of the emerging human flu viruses. Inactivated swine influenza virus (SwIV) vaccine has been in use in the US swine herds, but it failed to control the flu outbreaks. The main reason has been attributed to lack of induction of strong local mucosal immunity in the respiratory tract. Invariant natural killer T (iNKT) cell is a unique T cell subset, and activation of iNKT cell using its ligand α-Galactosylceramide (α-GalCer) has been shown to potentiate the cross-protective immunity to inactivated influenza virus vaccine candidates in mice. Recently, we discovered iNKT cell in pig and demonstrated its activation using α-GalCer. In this study, we evaluated the efficacy of an inactivated H1N1 SwIV coadministered with α-GalCer intranasally against a homologous viral challenge. Our results demonstrated the potent adjuvant effects of α-GalCer in potentiating both innate and adaptive immune responses to SwIV Ags in the lungs of pigs, which resulted in reduction in the lung viral load by 3 logs compared to without adjuvant. Immunologically, in the lungs of pigs vaccinated with α-GalCer an increased virus specific IgA response, IFN-α secretion and NK cell-cytotoxicity was observed. In addition, iNKT cell-stimulation enhanced the secretion of Th1 cytokines (IFN-γ and IL-12) and reduced the production of immunosuppressive cytokines (IL-10 and TGF-β) in the lungs of pigs⋅ In conclusion, we demonstrated for the first time iNKT cell adjuvant effects in pigs to SwIV Ags through augmenting the innate and adaptive immune responses in the respiratory tract. Copyright © 2016 Elsevier B.V. All rights reserved.

Emergence of swine flu in Andhra Pradesh: Facts and future.

PubMed

Venkataramana, Musturi; Vindal, Vaibhav; Kondapi, Anand K

2009-12-01

Swine flu is a common term representing the respiratory viral infections caused by influenza A virus strain H1N1. This disease was noticed for the first time in Mexico during early 2009, spread worldwide very soon and took nearly 4000 lives. It is observed that this infection is due to an evolved virulent version of previously existing H1N1. The first report of this infection was noticed in a traveler from USA to India at the Hyderabad international airport. Later, because of its highly contagious and fast-spreading nature through air, many people reported to have the infection throughout the country. In Andhra Pradesh, there were 735 officially confirmed cases of which 44 died. These cases were not only from Hyderabad which is the state capital having frequent travelers from abroad but are also reported from different parts of the state. The incidence and mortality rate is less in Andhra Pradesh compared to some of the other Indian states. This raises a question whether the type of the strain is different or genetic features of the population is playing the role in reducing the severity of the disease. In this review we have discussed about the occurrence, spread and mortality of the current H1N1 pandemic. We have also discussed about the current status of research on H1N1 and efforts in the state of Andhra Pradesh.

Monitoring the emergence of community transmission of influenza A/H1N1 2009 in England: a cross sectional opportunistic survey of self sampled telephone callers to NHS Direct.

PubMed

Elliot, Alex J; Powers, Cassandra; Thornton, Alicia; Obi, Chinelo; Hill, Caterina; Simms, Ian; Waight, Pauline; Maguire, Helen; Foord, David; Povey, Enid; Wreghitt, Tim; Goddard, Nichola; Ellis, Joanna; Bermingham, Alison; Sebastianpillai, Praveen; Lackenby, Angie; Zambon, Maria; Brown, David; Smith, Gillian E; Gill, O Noel

2009-08-27

To evaluate ascertainment of the onset of community transmission of influenza A/H1N1 2009 (swine flu) in England during the earliest phase of the epidemic through comparing data from two surveillance systems. Cross sectional opportunistic survey. Results from self samples by consenting patients who had called the NHS Direct telephone health line with cold or flu symptoms, or both, and results from Health Protection Agency (HPA) regional microbiology laboratories on patients tested according to the clinical algorithm for the management of suspected cases of swine flu. Six regions of England between 24 May and 30 June 2009. Proportion of specimens with laboratory evidence of influenza A/H1N1 2009. Influenza A/H1N1 2009 infections were detected in 91 (7%) of the 1385 self sampled specimens tested. In addition, eight instances of influenza A/H3 infection and two cases of influenza B infection were detected. The weekly rate of change in the proportions of infected individuals according to self obtained samples closely matched the rate of increase in the proportions of infected people reported by HPA regional laboratories. Comparing the data from both systems showed that local community transmission was occurring in London and the West Midlands once HPA regional laboratories began detecting 100 or more influenza A/H1N1 2009 infections, or a proportion positive of over 20% of those tested, each week. Trends in the proportion of patients with influenza A/H1N1 2009 across regions detected through clinical management were mirrored by the proportion of NHS Direct callers with laboratory confirmed infection. The initial concern that information from HPA regional laboratory reports would be too limited because it was based on testing patients with either travel associated risk or who were contacts of other influenza cases was unfounded. Reports from HPA regional laboratories could be used to recognise the extent to which local community transmission was occurring.

Assessing Google Flu Trends Performance in the United States during the 2009 Influenza Virus A (H1N1) Pandemic

PubMed Central

Cook, Samantha; Conrad, Corrie; Fowlkes, Ashley L.; Mohebbi, Matthew H.

2011-01-01

Background Google Flu Trends (GFT) uses anonymized, aggregated internet search activity to provide near-real time estimates of influenza activity. GFT estimates have shown a strong correlation with official influenza surveillance data. The 2009 influenza virus A (H1N1) pandemic [pH1N1] provided the first opportunity to evaluate GFT during a non-seasonal influenza outbreak. In September 2009, an updated United States GFT model was developed using data from the beginning of pH1N1. Methodology/Principal Findings We evaluated the accuracy of each U.S. GFT model by comparing weekly estimates of ILI (influenza-like illness) activity with the U.S. Outpatient Influenza-like Illness Surveillance Network (ILINet). For each GFT model we calculated the correlation and RMSE (root mean square error) between model estimates and ILINet for four time periods: pre-H1N1, Summer H1N1, Winter H1N1, and H1N1 overall (Mar 2009–Dec 2009). We also compared the number of queries, query volume, and types of queries (e.g., influenza symptoms, influenza complications) in each model. Both models' estimates were highly correlated with ILINet pre-H1N1 and over the entire surveillance period, although the original model underestimated the magnitude of ILI activity during pH1N1. The updated model was more correlated with ILINet than the original model during Summer H1N1 (r = 0.95 and 0.29, respectively). The updated model included more search query terms than the original model, with more queries directly related to influenza infection, whereas the original model contained more queries related to influenza complications. Conclusions Internet search behavior changed during pH1N1, particularly in the categories “influenza complications” and “term for influenza.” The complications associated with pH1N1, the fact that pH1N1 began in the summer rather than winter, and changes in health-seeking behavior each may have played a part. Both GFT models performed well prior to and during pH1N1

Characterization of Monoclonal Antibodies against HA Protein of H1N1 Swine Influenza Virus and Protective Efficacy against H1 Viruses in Mice.

PubMed

Liu, Yun; Li, Hongtao; Xue, Yujia; Zhao, Shuang; Li, Chenxi; Qu, Liandong; Zhang, Yun; Liu, Ming

2017-08-08

H1N1 swine influenza viruses (SIV) are prevalent in pigs globally, and occasionally emerge in humans, which raises concern about their pandemic threats. To stimulate hemagglutination (HA) of A/Swine/Guangdong/LM/2004 (H1N1) (SW/GD/04) antibody response, eukaryotic expression plasmid pCI-neo-HA was constructed and used as an immunogen to prepare monoclonal antibodies (mAbs). Five mAbs (designed 8C4, 8C6, 9D6, 8A4, and 8B1) against HA protein were obtained and characterized. Western blot showed that the 70 kDa HA protein could be detected by all mAbs in MDCK cells infected with SW/GD/04. Three mAbs-8C4, 8C6, and 9D6-have hemagglutination inhibition (HI) and neutralization test (NT) activities, and 8C6 induces the highest HI and NT titers. The protection efficacy of 8C6 was investigated in BALB/c mice challenged with homologous or heterologous strains of the H1 subtype SIV. The results indicate that mAb 8C6 protected the mice from viral infections, especially the homologous strain, which was clearly demonstrated by the body weight changes and reduction of viral load. Thus, our findings document for the first time that mAb 8C6 might be of potential therapeutic value for H1 subtype SIV infection.

Evaluation of the zoonotic potential of a novel reassortant H1N2 swine influenza virus with gene constellation derived from multiple viral sources.

PubMed

Lee, Jee Hoon; Pascua, Philippe Noriel Q; Decano, Arun G; Kim, Se Mi; Park, Su-Jin; Kwon, Hyeok-Il; Kim, Eun-Ha; Kim, Young-Il; Kim, HyongKyu; Kim, Seok-Yong; Song, Min-Suk; Jang, Hyung-Kwan; Park, Bong Kyun; Choi, Young Ki

2015-08-01

In 2011-2012, contemporary North American-like H3N2 swine influenza viruses (SIVs) possessing the 2009 pandemic H1N1 matrix gene (H3N2pM-like virus) were detected in domestic pigs of South Korea where H1N2 SIV strains are endemic. More recently, we isolated novel reassortant H1N2 SIVs bearing the Eurasian avian-like swine H1-like hemagglutinin and Korean swine H1N2-like neuraminidase in the internal gene backbone of the H3N2pM-like virus. In the present study, we clearly provide evidence on the genetic origins of the novel H1N2 SIVs virus through genetic and phylogenetic analyses. In vitro studies demonstrated that, in comparison with a pre-existing 2012 Korean H1N2 SIV [A/swine/Korea/CY03-11/2012 (CY03-11/2012)], the 2013 novel reassortant H1N2 isolate [A/swine/Korea/CY0423/2013 (CY0423-12/2013)] replicated more efficiently in differentiated primary human bronchial epithelial cells. The CY0423-12/2013 virus induced higher viral titers than the CY03-11/2012 virus in the lungs and nasal turbinates of infected mice and nasal wash samples of ferrets. Moreover, the 2013 H1N2 reassortant, but not the intact 2012 H1N2 virus, was transmissible to naïve contact ferrets via respiratory-droplets. Noting that the viral precursors have the ability to infect humans, our findings highlight the potential threat of a novel reassortant H1N2 SIV to public health and underscore the need to further strengthen influenza surveillance strategies worldwide, including swine populations. Copyright © 2015 Elsevier B.V. All rights reserved.

Two different genotypes of H1N2 swine influenza virus isolated in northern China and their pathogenicity in animals.

PubMed

Yang, Huanliang; Chen, Yan; Qiao, Chuanling; Xu, Chuantian; Yan, Minghua; Xin, Xiaoguang; Bu, Zhigao; Chen, Hualan

2015-02-25

During 2006 and 2007, two swine-origin triple-reassortant influenza A (H1N2) viruses were isolated from pigs in northern China, and the antigenic characteristics of the hemagglutinin protein of the viruses were examined. Genotyping and phylogenetic analyses demonstrated different emergence patterns for the two H1N2 viruses, Sw/Hebei/10/06 and Sw/Tianjin/1/07. Sequences for the other genes encoding the internal proteins were compared with the existing data to determine their origins and establish the likely mechanisms of genetic reassortment. Sw/Hebei/10/06 is an Sw/Indiana/9K035/99-like virus, whereas Sw/Tianjin/1/07 represents a new H1N2 genotype with surface genes of classic swine and human origin and internal genes originating from the Eurasian avian-like swine H1N1 virus. Six-week-old female BALB/c mice infected with the Sw/HeB/10/06 and Sw/TJ/1/07 viruses showed an average weight loss of 12.8% and 8.1%, respectively. Healthy six-week-old pigs were inoculated intranasally with either the Sw/HeB/10/06 or Sw/TJ/1/07 virus. No considerable changes in the clinical presentation were observed post-inoculation in any of the virus-inoculated groups, and the viruses effectively replicated in the nasal cavity and lung tissue. Based on the results, it is possible that the new genotype of the swine H1N2 virus that emerged in China may become widespread in the swine population and pose a potential threat to public health. Copyright © 2014 Elsevier B.V. All rights reserved.

Novel triple reassortant H1N2 influenza viruses bearing six internal genes of the pandemic 2009/H1N1 influenza virus were detected in pigs in China.

PubMed

Qiao, Chuanling; Liu, Liping; Yang, Huanliang; Chen, Yan; Xu, Huiyang; Chen, Hualan

2014-12-01

The pandemic A/H1N1 influenza viruses emerged in both Mexico and the United States in March 2009, and were transmitted efficiently in the human population. Transmissions of the pandemic 2009/H1N1 virus from humans to poultry and other species of mammals were reported from several continents during the course of the 2009 H1N1 pandemic. Reassortant H1N1, H1N2, and H3N2 viruses containing genes of the pandemic 2009/H1N1 viruses appeared in pigs in some countries. In winter of 2012, a total of 2600 nasal swabs were collected from healthy pigs in slaughterhouses located throughout 10 provinces in China. The isolated viruses were subjected to genetic and antigenic analysis. Two novel triple-reassortant H1N2 influenza viruses were isolated from swine in China in 2012, with the HA gene derived from Eurasian avian-like swine H1N1, the NA gene from North American swine H1N2, and the six internal genes from the pandemic 2009/H1N1 viruses. The two viruses had similar antigenic features and some significant changes in antigenic characteristics emerged when compared to the previously identified isolates. We inferred that the novel reassortant viruses in China may have arisen from the accumulation of the three types of influenza viruses, which further indicates that swine herds serve as "mixing vessels" for influenza viruses. Influenza virus reassortment is an ongoing process, and our findings highlight the urgent need for continued influenza surveillance among swine herds. Copyright © 2014 Elsevier B.V. All rights reserved.

[Political dimensions of an epidemic: the case of influenza A (H1N1) in the Argentine press].

PubMed

Sy, Anahi; Spinelli, Hugo

2016-03-01

The current study addresses social representations of the influenza A (H1N1) epidemic in Argentina in 2009, in the country's mainstream newspapers. The methodology was twofold, qualitative and quantitative, with an analysis of two dimensions: the construction of the epidemic as an "object" (designation and characterization) and the sources of information in the news stories, seeking to identify the social actors involved in each case. The results show that designating the epidemic as "H1N1" rather than "swine flu" was a conscious political decision to exempt a hazardous form of livestock production from its role in the disease, while focusing responsibility on individual patients. The study addresses the relations between recommendations by policy spokespersons (especially at the international level), the pharmaceuticalization of the epidemic, shifting of the population's demands to validate biomedical hegemony, and local press coverage of the epidemic.

A monoclonal antibody-based ELISA for differential diagnosis of 2009 pandemic H1N1

USDA-ARS?s Scientific Manuscript database

The swine-origin 2009 pandemic H1N1 virus (pdmH1N1) is genetically related to North American swine H1 influenza viruses and unrelated to human seasonal H1 viruses. Currently, specific diagnosis of pdmH1N1 relies on RT-PCR. In order to develop an assay that does not rely in amplification of the viral...

Swine influenza virus vaccine serologic cross-reactivity to contemporary US swine H3N2 and efficacy in pigs infected with an H3N2 similar to 2011-2012 H3N2v.

PubMed

Kitikoon, Pravina; Gauger, Phillip C; Anderson, Tavis K; Culhane, Marie R; Swenson, Sabrina; Loving, Crystal L; Perez, Daniel R; Vincent, Amy L

2013-12-01

Swine influenza A virus (IAV) reassortment with 2009 H1N1 pandemic (H1N1pdm09) virus has been documented, and new genotypes and subclusters of H3N2 have since expanded in the US swine population. An H3N2 variant (H3N2v) virus with the H1N1pdm09 matrix gene and the remaining genes of swine triple reassortant H3N2 caused outbreaks at agricultural fairs in 2011-2012. To assess commercial swine IAV vaccines' efficacy against H3N2 viruses, including those similar to H3N2v, antisera to three vaccines were tested by hemagglutinin inhibition (HI) assay against contemporary H3N2. Vaccine 1, with high HI cross-reactivity, was further investigated for efficacy against H3N2 virus infection in pigs with or without maternally derived antibodies (MDA). In addition, efficacy of a vaccine derived from whole inactivated virus (WIV) was compared with live attenuated influenza virus (LAIV) against H3N2. Hemagglutinin inhibition cross-reactivity demonstrated that contemporary swine H3N2 viruses have drifted from viruses in current swine IAV vaccines. The vaccine with the highest level of HI cross-reactivity significantly protected pigs without MDA. However, the presence of MDA at vaccination blocked vaccine efficacy. The performance of WIV and LAIV was comparable in the absence of MDA. Swine IAV in the United States is complex and dynamic. Vaccination to minimize virus shedding can help limit transmission of virus among pigs and people. However, vaccines must be updated. A critical review of the use of WIV in sows is required in the context of the current IAV ecology and vaccine application in pigs with MDA. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Virulence and transmissibility of H1N2 influenza virus in ferrets imply the continuing threat of triple-reassortant swine viruses.

PubMed

Pascua, Philippe Noriel Q; Song, Min-Suk; Lee, Jun Han; Baek, Yun Hee; Kwon, Hyeok-il; Park, Su-Jin; Choi, Eun Hye; Lim, Gyo-Jin; Lee, Ok-Jun; Kim, Si-Wook; Kim, Chul-Joong; Sung, Moon Hee; Kim, Myung Hee; Yoon, Sun-Woo; Govorkova, Elena A; Webby, Richard J; Webster, Robert G; Choi, Young-Ki

2012-09-25

Efficient worldwide swine surveillance for influenza A viruses is urgently needed; the emergence of a novel reassortant pandemic H1N1 (pH1N1) virus in 2009 demonstrated that swine can be the direct source of pandemic influenza and that the pandemic potential of viruses prevalent in swine populations must be monitored. We used the ferret model to assess the pathogenicity and transmissibility of predominant Korean triple-reassortant swine (TRSw) H1N2 and H3N2 influenza viruses genetically related to North American strains. Although most of the TRSw viruses were moderately pathogenic, one [A/Swine/Korea/1204/2009; Sw/1204 (H1N2)] was virulent in ferrets, causing death within 10 d of inoculation, and was efficiently transmitted to naive contact ferrets via respiratory droplets. Although molecular analysis did not reveal known virulence markers, the Sw/1204 virus acquired mutations in hemagglutinin (HA) (Asp-225-Gly) and neuraminidase (NA) (Ser-315-Asn) proteins during the single ferret passage. The contact-Sw/1204 virus became more virulent in mice, replicated efficiently in vitro, extensively infected human lung tissues ex vivo, and maintained its ability to replicate and transmit in swine. Reverse-genetics studies further indicated that the HA(225G) and NA(315N) substitutions contributed substantially in altering virulence and transmissibility. These findings support the continuing threat of some field TRSw viruses to human and animal health, reviving concerns on the capacity of pigs to create future pandemic viruses. Apart from warranting continued and enhanced global surveillance, this study also provides evidence on the emerging roles of HA(225G) and NA(315N) as potential virulence markers in mammals.

[Phylogenetic analysis of human/swine/avian gene reassortant H1N2 influenza A virus isolated from a pig in China].

PubMed

Chen, Yixiang; Meng, Xueqiong; Liu, Qi; Huang, Xia; Huang, Shengbin; Liu, Cuiquan; Shi, Kaichuang; Guo, Jiangang; Chen, Fangfang; Hu, Liping

2008-04-01

Our aim in this study was to determine the genetic characterization and probable origin of the H1N2 swine influenza virus (A/Swine/Guangxi/13/2006) (Sw/GX/13/06) from lung tissue of a pig in Guangxi province, China. Eight genes of Sw/GX/13/06 were cloned and genetically analyzed. The hemagglutinin (HA), nucleoprotein (NP), matrix (M) and non-structural (NS) genes of Sw/GX/13/06 were most closely related to genes from the classical swine H1N1 influenza virus lineage. The neuraminidase (NA) and PB1 genes were most closely related to the corresponding genes from the human influenza H3N2 virus lineage. The remaining two genes PA and PB2 polymerase genes were most closely related to the genes from avian influenza virus lineage. Phylogenetic analyses revealed that Sw/GX/13/06 was a human/swine/avian H1N2 virus, and closely related to H1N2 viruses isolated from pigs in United States (1999-2001) and Korea (2002). To our knowledge, Sw/GX/13/06 was the first triple-reassortant H1N2 influenza A virus isolated from a pig in China. Whether the Sw/GX/13/06 has a potential threat to breeding farm and human health remains to be further investigated.

Connecting the dots between swine influenza A virus surveillance and vaccines

USDA-ARS?s Scientific Manuscript database

Introduction Influenza A virus (IAV) infection was first recognized in the USA swine population following the 1918 Spanish flu pandemic in humans with the identification of an H1N1 virus that became known as the classical swine H1N1. In 1997-98, the incursion of the triple reassortant viruses with g...

Winthrop-University Hospital Infectious Disease Division's swine influenza (H1N1) pneumonia diagnostic weighted point score system for hospitalized adults with influenza-like illnesses (ILIs) and negative rapid influenza diagnostic tests (RIDTs).

PubMed

Cunha, Burke A; Syed, Uzma; Stroll, Stephanie; Mickail, Nardeen; Laguerre, Marianne

2009-01-01

In spring 2009, a novel strain of influenza A originating in Veracruz, Mexico, quickly spread to the United States and throughout the world. This influenza A virus was the product of gene reassortment of 4 different genetic elements: human influenza, swine influenza, avian influenza, and Eurasian swine influenza. In the United States, New York was the epicenter of the swine influenza (H1N1) pandemic. Hospital emergency departments (EDs) were inundated with patients with influenza-like illnesses (ILIs) requesting screening for H1N1. Our ED screening, as well as many others, used a rapid screening test for influenza A (QuickVue A/B) because H1N1 was a variant of influenza A. The definitive laboratory test i.e., RT-PCR for H1N1 was developed by the Centers for Disease Control (Atlanta, GA) and subsequently distributed to health departments. Because of the extraordinary volume of test requests, health authorities restricted reverse transcription polymerase chain reaction (RT-PCR) testing. Hence most EDs, including our own, were dependent on rapid influenza diagnostic tests (RIDTs) for swine influenza. A positive rapid influenza A test was usually predictive of RT-PCR H1N1 positivity, but the rapid influenza A screening test (QuickVue A/B) was associated with 30% false negatives. The inability to rely on RIDTs for H1N1 diagnosis resulted in underdiagnosing H1N1. Confronted with adults admitted with ILIs, negative RIDTs, and restricted RT-PCR testing, there was a critical need to develop clinical criteria to diagnose probable swine influenza H1N1 pneumonia. During the pandemic, the Infectious Disease Division at Winthrop-University Hospital developed clinical criteria for adult admitted patients with ILIs and negative RIDTs. Similar to the one developed for the clinical diagnosis of legionnaire's disease. The Winthrop-University Hospital Infectious Disease Division's diagnostic weighted point score system for swine influenza H1N1 pneumonia is based on key clinical and

Swine influenza virus vaccine serologic cross-reactivity to contemporary U.S. swine H3N2 and efficacy in pigs infected with an H3N2 similar to 2011-2012 H3N2v

USDA-ARS?s Scientific Manuscript database

Background: Swine influenza A virus (IAV) reassortment with 2009 H1N1 pandemic (H1N1pdm09) virus has been documented and new genotypes and sub-clusters of H3N2 have since expanded in the U.S. swine population. An H3N2 variant (H3N2v) virus with the H1N1pdm09 matrix gene and the remaining genes of sw...

Immunization of pigs with an attenuated pseudorabies virus recombinant expressing the haemagglutinin of pandemic swine origin H1N1 influenza A virus.

PubMed

Klingbeil, Katharina; Lange, Elke; Teifke, Jens P; Mettenleiter, Thomas C; Fuchs, Walter

2014-04-01

Pigs can be severely harmed by influenza, and represent important reservoir hosts, in which new human pathogens such as the recent pandemic swine-origin H1N1 influenza A virus can arise by mutation and reassortment of genome segments. To obtain novel, safe influenza vaccines for pigs, and to investigate the antigen-specific immune response, we modified an established live-virus vaccine against Aujeszky's disease of swine, pseudorabies virus (PrV) strain Bartha (PrV-Ba), to serve as vector for the expression of haemagglutinin (HA) of swine-origin H1N1 virus. To facilitate transgene insertion, the genome of PrV-Ba was cloned as a bacterial artificial chromosome. HA expression occurred under control of the human or murine cytomegalovirus immediate early promoters (P-HCMV, P-MCMV), but could be substantially enhanced by synthetic introns and adaptation of the codon usage to that of PrV. However, despite abundant expression, the heterologous glycoprotein was not detectably incorporated into mature PrV particles. Replication of HA-expressing PrV in cell culture was only slightly affected compared to that of the parental virus strain. A single immunization of pigs with the PrV vector expressing the codon-optimized HA gene under control of P-MCMV induced high levels of HA-specific antibodies. The vaccinated animals were protected from clinical signs after challenge with a related swine-origin H1N1 influenza A virus, and challenge virus shedding was significantly reduced.

2009 pandemic H1N1 influenza virus elicits similar clinical course but differential host transcriptional response in mouse, macaque, and swine infection models

PubMed Central

2012-01-01

Background The 2009 pandemic H1N1 influenza virus emerged in swine and quickly became a major global health threat. In mouse, non human primate, and swine infection models, the pH1N1 virus efficiently replicates in the lung and induces pro-inflammatory host responses; however, whether similar or different cellular pathways were impacted by pH1N1 virus across independent infection models remains to be further defined. To address this we have performed a comparative transcriptomic analysis of acute phase responses to a single pH1N1 influenza virus, A/California/04/2009 (CA04), in the lung of mice, macaques and swine. Results Despite similarities in the clinical course, we observed differences in inflammatory molecules elicited, and the kinetics of their gene expression changes across all three species. We found genes associated with the retinoid X receptor (RXR) signaling pathway known to control pro-inflammatory and metabolic processes that were differentially regulated during infection in each species, though the heterodimeric RXR partner, pathway associated signaling molecules, and gene expression patterns varied among the three species. Conclusions By comparing transcriptional changes in the context of clinical and virological measures, we identified differences in the host transcriptional response to pH1N1 virus across independent models of acute infection. Antiviral resistance and the emergence of new influenza viruses have placed more focus on developing drugs that target the immune system. Underlying overt clinical disease are molecular events that suggest therapeutic targets identified in one host may not be appropriate in another. PMID:23153050

Infection dynamics of pandemic 2009 H1N1 influenza virus in a two-site swine herd.

PubMed

Allerson, M W; Davies, P R; Gramer, M R; Torremorell, M

2014-12-01

Influenza A viruses are common causes of respiratory disease in pigs and can be transmitted among multiple host species, including humans. The current lack of published information on infection dynamics of influenza viruses within swine herds hinders the ability to make informed animal health, biosecurity and surveillance programme decisions. The objectives of this serial cross-sectional study were to describe the infection dynamics of influenza virus in a two-site swine system by estimating the prevalence of influenza virus in animal subpopulations at the swine breeding herd and describing the temporal pattern of infection in a selected cohort of growing pigs weaned from the breeding herd. Nasal swab and blood samples were collected at approximately 30-day intervals from the swine breeding herd (Site 1) known to be infected with pandemic 2009 H1N1 influenza virus. Sows, gilts and neonatal pigs were sampled at each sampling event, and samples were tested for influenza virus genome using matrix gene RRT-PCR. Influenza virus was detected in neonatal pigs, but was not detected in sow or gilt populations via RRT-PCR. A virus genetically similar to that detected in the neonatal pig population at Site 1 was also detected at the wean-to-finish site (Site 2), presumably following transportation of infected weaned pigs. Longitudinal sampling of nasal swabs and oral fluids revealed that influenza virus persisted in the growing pigs at Site 2 for at least 69 days. The occurrence of influenza virus in neonatal pigs, but not breeding females, at Site 1 emphasizes the potential for virus maintenance in this dynamic subpopulation, the importance of including this subpopulation in surveillance programmes and the potential transport of influenza virus between sites via the movement of weaned pigs. © 2013 Blackwell Verlag GmbH.

Control of endemic swine flu persistence in farrow-to-finish pig farms: a stochastic metapopulation modeling assessment.

PubMed

Cador, Charlie; Andraud, Mathieu; Willem, Lander; Rose, Nicolas

2017-10-03

Swine influenza viruses (swIAVs) are known to persist endemically in farrow-to-finish pig farms, leading to repeated swine flu outbreaks in successive batches of pigs at a similar age (mostly around 8 weeks of age). This persistence in European swine herds involves swIAVs from European lineages including H1 av N1, H1 hu N2, H3N2, the 2009 H1N1 pandemic virus and their reassortants. The specific population dynamics of farrow-to-finish pig farms, the immune status of the animals at infection-time, the co-circulation of distinct subtypes leading to consecutive or concomitant infections have been evidenced as factors favouring swIAV persistence within herds. We developed a stochastic metapopulation model representing the co-circulation of two distinct swIAVs within a typical farrow-to-finish pig herd to evaluate the risk of reassortant viruses generation due to co-infection events. Control strategies related to herd management and/or vaccination schemes (batch-to-batch or mass vaccination of the sow herd and vaccination of growing pigs) were implemented to assess their relative efficacy regarding viral persistence. The overall probability of a co-infection event for France, possibly leading to reassortment, was evaluated to 16.8%. The export of consecutive piglets batches was identified as the most efficient measure facilitating swIAV infection fade-out. Although some vaccination schemes (batch-to-batch vaccination) had a beneficial effect in breeding sows by reducing the persistence of swIAVs within this subpopulation, none of vaccination strategies achieved swIAVs fade-out within the entire farrow-to-finish pig herd.

Lymphadenitis as a Rare Side Effect of H1N1 Vaccine in a Child

PubMed Central

Gundogdu, Zuhal; Seyhogullari, Mualla

2010-01-01

We present a 5-year-old boy who had the complaint of swelling and pain on the right vaccine shot and right axillary areas. The right axillary area was diagnosed as reactive lymphadenitis, which we believe is a rare local side effect of the swine flu vaccine. The key message to take away from this case is that the patient had lymphadenitis as a local side effect of the swine flu vaccine. Lymphadenitis should be reported as a possible local side effect of the swine flu vaccine. PMID:21209734

Integrative analysis of differentially expressed microRNAs of pulmonary alveolar macrophages from piglets during H1N1 swine influenza A virus infection

PubMed Central

Jiang, Pengfei; Zhou, Na; Chen, Xinyu; Zhao, Xing; Li, Dengyun; Wang, Fen; Bi, Lijun; Zhang, Deli

2015-01-01

H1N1 swine influenza A virus (H1N1 SwIV) is one key subtype of influenza viruses with pandemic potential. MicroRNAs (miRNAs) are endogenous small RNA molecules that regulate gene expression. MiRNAs relevant with H1N1 SwIV have rarely been reported. To understand the biological functions of miRNAs during H1N1 SwIV infection, this study profiled differentially expressed (DE) miRNAs in pulmonary alveolar macrophages from piglets during the H1N1 SwIV infection using a deep sequencing approach, which was validated by quantitative real-time PCR. Compared to control group, 70 and 16 DE miRNAs were respectively identified on post-infection day (PID) 4 and PID 7. 56 DE miRNAs were identified between PID 4 and PID 7. Our results suggest that most host miRNAs are down-regulated to defend the H1N1 SwIV infection during the acute phase of swine influenza whereas their expression levels gradually return to normal during the recovery phase to avoid the occurrence of too severe porcine lung damage. In addition, targets of DE miRNAs were also obtained, for which bioinformatics analyses were performed. Our results would be useful for investigating the functions and regulatory mechanisms of miRNAs in human influenza because pig serves as an excellent animal model to study the pathogenesis of human influenza. PMID:25639204

Avian flu school: a training approach to prepare for H5N1 highly pathogenic avian influenza.

PubMed

Beltran-Alcrudo, Daniel; Bunn, David A; Sandrock, Christian E; Cardona, Carol J

2008-01-01

Since the reemergence of highly pathogenic avian influenza (H5N1 HPAI) in 2003, a panzootic that is historically unprecedented in the number of infected flocks, geographic spread, and economic consequences for agriculture has developed. The epidemic has affected a wide range of birds and mammals, including humans. The ineffective management of outbreaks, mainly due to a lack of knowledge among those involved in detection, prevention, and response, points to the need for training on H5N1 HPAI. The main challenges are the multidisciplinary approach required, the lack of experts, the need to train at all levels, and the diversity of outbreak scenarios. Avian Flu School addresses these challenges through a three-level train-the-trainer program intended to minimize the health and economic impacts of H5N1 HPAI by improving a community's ability to prevent and respond, while protecting themselves and others. The course teaches need-to-know facts using highly flexible, interactive, and relevant materials.

Antigenic and genetic evolution of contemporary swine H1 influenza viruses in the United States.

PubMed

Rajao, Daniela S; Anderson, Tavis K; Kitikoon, Pravina; Stratton, Jered; Lewis, Nicola S; Vincent, Amy L

2018-05-01

Several lineages of influenza A viruses (IAV) currently circulate in North American pigs. Genetic diversity is further increased by transmission of IAV between swine and humans and subsequent evolution. Here, we characterized the genetic and antigenic evolution of contemporary swine H1N1 and H1N2 viruses representing clusters H1-α (1A.1), H1-β (1A.2), H1pdm (1A.3.3.2), H1-γ (1A.3.3.3), H1-δ1 (1B.2.2), and H1-δ2 (1B.2.1) currently circulating in pigs in the United States. The δ1-viruses diversified into two new genetic clades, H1-δ1a (1B.2.2.1) and H1-δ1b (1B.2.2.2), which were also antigenically distinct from the earlier H1-δ1-viruses. Further characterization revealed that a few key amino acid changes were associated with antigenic divergence in these groups. The continued genetic and antigenic evolution of contemporary H1 viruses might lead to loss of vaccine cross-protection that could lead to significant economic impact to the swine industry, and represents a challenge to public health initiatives that attempt to minimize swine-to-human IAV transmission. Published by Elsevier Inc.

Deciphering the Swine-Flu Pandemics of 1918 and 2009

NASA Astrophysics Data System (ADS)

Goldstein, Richard; Dos Reis, Mario; Tamuri, Asif; Hay, Alan

The devastating "Spanish flu" of 1918 killed an estimated 50 million people worldwide, ranking it as the deadliest pandemic in recorded human history. It is generally believed that the virus transferred from birds directly to humans shortly before the start of the pandemic, subsequently jumping from humans to swine. By developing 'non-homogeneous' substitution models that consider that substitution patterns may be different in human, avian, and swine hosts, we can determine the timing of the host shift to mammals. We find it likely that the Spanish flu of 1918, like the current 2009 pandemic, was a 'swine-origin' influenza virus. Now that we are faced with a new pandemic, can we understand how influenza is able to change hosts? Again by modelling the evolutionary process, considering the different selective constraints for viruses in the different hosts, we can identify locations that seem to be under different selective constraints in humans and avian hosts. This allows us to identify changes that may have facilitated the establishment of the 2009 swine-origin flu in humans.

A Historical Perspective of Influenza A(H1N2) Virus

PubMed Central

McVernon, Jodie; Hall, Robert; Leder, Karin

2014-01-01

The emergence and transition to pandemic status of the influenza A(H1N1)A(H1N1)pdm09) virus in 2009 illustrated the potential for previously circulating human viruses to re-emerge in humans and cause a pandemic after decades of circulating among animals. Within a short time of the initial emergence of A(H1N1)pdm09 virus, novel reassortants were isolated from swine. In late 2011, a variant (v) H3N2 subtype was isolated from humans, and by 2012, the number of persons infected began to increase with limited person-to-person transmission. During 2012 in the United States, an A(H1N2)v virus was transmitted to humans from swine. During the same year, Australia recorded its first H1N2 subtype infection among swine. The A(H3N2)v and A(H1N2)v viruses contained the matrix protein from the A(H1N1)pdm09 virus, raising the possibility of increased transmissibility among humans and underscoring the potential for influenza pandemics of novel swine-origin viruses. We report on the differing histories of A(H1N2) viruses among humans and animals. PMID:24377419

A historical perspective of influenza A(H1N2) virus.

PubMed

Komadina, Naomi; McVernon, Jodie; Hall, Robert; Leder, Karin

2014-01-01

The emergence and transition to pandemic status of the influenza A(H1N1)A(H1N1)pdm09) virus in 2009 illustrated the potential for previously circulating human viruses to re-emerge in humans and cause a pandemic after decades of circulating among animals. Within a short time of the initial emergence of A(H1N1)pdm09 virus, novel reassortants were isolated from swine. In late 2011, a variant (v) H3N2 subtype was isolated from humans, and by 2012, the number of persons infected began to increase with limited person-to-person transmission. During 2012 in the United States, an A(H1N2)v virus was transmitted to humans from swine. During the same year, Australia recorded its first H1N2 subtype infection among swine. The A(H3N2)v and A(H1N2)v viruses contained the matrix protein from the A(H1N1)pdm09 virus, raising the possibility of increased transmissibility among humans and underscoring the potential for influenza pandemics of novel swine-origin viruses. We report on the differing histories of A(H1N2) viruses among humans and animals.

Polymerase Discordance in Novel Swine Influenza H3N2v Constellations Is Tolerated in Swine but Not Human Respiratory Epithelial Cells

PubMed Central

Powell, Joshua D.; Dlugolenski, Daniel; Nagy, Tamas; Gabbard, Jon; Lee, Christopher; Tompkins, Stephen M.; Tripp, Ralph A.

2014-01-01

Swine-origin H3N2v, a variant of H3N2 influenza virus, is a concern for novel reassortment with circulating pandemic H1N1 influenza virus (H1N1pdm09) in swine because this can lead to the emergence of a novel pandemic virus. In this study, the reassortment prevalence of H3N2v with H1N1pdm09 was determined in swine cells. Reassortants evaluated showed that the H1N1pdm09 polymerase (PA) segment occurred within swine H3N2 with ∼80% frequency. The swine H3N2-human H1N1pdm09 PA reassortant (swH3N2-huPA) showed enhanced replication in swine cells, and was the dominant gene constellation. Ferrets infected with swH3N2-huPA had increased lung pathogenicity compared to parent viruses; however, swH3N2-huPA replication in normal human bronchoepithelial cells was attenuated - a feature linked to expression of IFN-β and IFN-λ genes in human but not swine cells. These findings indicate that emergence of novel H3N2v influenza constellations require more than changes in the viral polymerase complex to overcome barriers to cross-species transmission. Additionally, these findings reveal that while the ferret model is highly informative for influenza studies, slight differences in pathogenicity may not necessarily be indicative of human outcomes after infection. PMID:25330303

Pathogenicity and Transmissibility of Novel Reassortant H3N2 Influenza Viruses with 2009 Pandemic H1N1 Genes in Pigs

PubMed Central

Ma, Jingjiao; Shen, Huigang; Liu, Qinfang; Bawa, Bhupinder; Qi, Wenbao; Duff, Michael; Lang, Yuekun; Lee, Jinhwa; Yu, Hai; Bai, Jianfa; Tong, Guangzhi; Hesse, Richard A.; Richt, Jürgen A.

2014-01-01

ABSTRACT At least 10 different genotypes of novel reassortant H3N2 influenza viruses with 2009 pandemic H1N1 [A(H1N1)pdm09] gene(s) have been identified in U.S. pigs, including the H3N2 variant with a single A(H1N1)pdm09 M gene, which has infected more than 300 people. To date, only three genotypes of these viruses have been evaluated in animal models, and the pathogenicity and transmissibility of the other seven genotype viruses remain unknown. Here, we show that three H3N2 reassortant viruses that contain 3 (NP, M, and NS) or 5 (PA, PB2, NP, M, and NS) genes from A(H1N1)pdm09 were pathogenic in pigs, similar to the endemic H3N2 swine virus. However, the reassortant H3N2 virus with 3 A(H1N1)pdm09 genes and a recent human influenza virus N2 gene was transmitted most efficiently among pigs, whereas the reassortant H3N2 virus with 5 A(H1N1)pdm09 genes was transmitted less efficiently than the endemic H3N2 virus. Interestingly, the polymerase complex of reassortant H3N2 virus with 5 A(H1N1)pdm09 genes showed significantly higher polymerase activity than those of endemic and reassortant H3N2 viruses with 3 A(H1N1)pdm09 genes. Further studies showed that an avian-like glycine at position 228 at the hemagglutinin (HA) receptor binding site is responsible for inefficient transmission of the reassortant H3N2 virus with 5 A(H1N1)pdm09 genes. Taken together, our results provide insights into the pathogenicity and transmissibility of novel reassortant H3N2 viruses in pigs and suggest that a mammalian-like serine at position 228 in the HA is critical for the transmissibility of these reassortant H3N2 viruses. IMPORTANCE Swine influenza is a highly contagious zoonotic disease that threatens animal and public health. Introduction of 2009 pandemic H1N1 virus [A(H1N1)pdm09] into swine herds has resulted in novel reassortant influenza viruses in swine, including H3N2 and H1N2 variants that have caused human infections in the United States. We showed that reassortant H3N2 influenza

Is the reporting timeliness gap for avian flu and H1N1 outbreaks in global health surveillance systems associated with country transparency?

PubMed

Tsai, Feng-Jen; Tseng, Eva; Chan, Chang-Chuan; Tamashiro, Hiko; Motamed, Sandrine; Rougemont, André C

2013-03-25

This study aims to evaluate the length of time elapsed between reports of the same incidents related to avian flu and H1N1 outbreaks published by the WHO and ProMED-mail, the two major global health surveillance systems, before and after the amendment of the International Health Regulations in 2005 (IHR 2005) and to explore the association between country transparency and this timeliness gap. We recorded the initial release dates of each report related to avian flu or H1N1 listed on the WHO Disease Outbreak News site and the matching outbreak report from ProMED-mail, a non-governmental program for monitoring emerging diseases, from 2003 to the end of June 2009. The timeliness gap was calculated as the difference in days between the report release dates of the matching outbreaks in the WHO and ProMED-mail systems. Civil liberties scores were collected as indicators of the transparency of each country. The Human Development Index and data indicating the density of physicians and nurses were collected to reflect countries' development and health workforce statuses. Then, logistic regression was performed to determine the correlation between the timeliness gap and civil liberties, human development, and health workforce status, controlling for year. The reporting timeliness gap for avian flu and H1N1 outbreaks significantly decreased after 2003. On average, reports were posted 4.09 (SD = 7.99) days earlier by ProMED-mail than by the WHO. Countries with partly free (OR = 5.77) and free civil liberties scores (OR = 10.57) had significantly higher likelihoods of longer timeliness gaps than non-free countries. Similarly, countries with very high human development status had significantly higher likelihoods of longer timeliness gaps than countries with middle or low human development status (OR = 5.30). However, no association between the timeliness gap and health workforce density was found. The study found that the adoption of IHR 2005, which contributed

Mitigation approaches to combat the flu pandemic.

PubMed

Chawla, Raman; Sharma, Rakesh Kumar; Madaan, Deepali; Dubey, Neha; Arora, Rajesh; Goel, Rajeev; Singh, Shefali; Kaushik, Vinod; Singh, Pankaj Kumar; Chabbra, Vivek; Bhardwaj, Janak Raj

2009-07-01

Management of flu pandemic is a perpetual challenge for the medical fraternity since time immemorial. Animal to human transmission has been observed thrice in the last century within an average range of 11-39 years of antigenic recycling. The recent outbreak of influenza A (H1N1, also termed as swine flu), first reported in Mexico on April 26, 2009, occurred in the forty first year since last reported flu pandemic (July 1968). Within less than 50 days, it has assumed pandemic proportions (phase VI) affecting over 76 countries with 163 deaths/35,928 cases (as on 15(th) June 2009). It indicated the re-emergence of genetically reassorted virus having strains endemic to humans, swine and avian (H5N1). The World Health Organisation (WHO) member states have already pulled up their socks and geared up to combat such criticalities. Earlier outbreaks of avian flu (H5N1) in different countries led WHO to develop pandemic preparedness strategies with national/regional plans on pandemic preparedness. Numerous factors related to climatic conditions, socio-economic strata, governance and sharing of information/logistics at all levels have been considered critical indicators in monitoring the dynamics of escalation towards a pandemic situation.The National Disaster Management Authority (NDMA), Government of India, with the active cooperation of UN agencies and other stakeholders/experts has formulated a concept paper on role of nonhealth service providers during pandemics in April 2008 and released national guidelines - management of biological disasters in July 2008. These guidelines enumerate that the success of medical management endeavors like pharmaceutical (anti-viral Oseltamivir and Zanamivir therapies), nonpharmaceutical interventions and vaccination development etc., largely depends on level of resistance offered by mutagenic viral strain and rationale use of pharmaco therapeutic interventions. This article describes the mitigation approach to combat flu pandemic with

Acute phase protein response during subclinical infection of pigs with H1N1 swine influenza virus.

PubMed

Pomorska-Mól, Małgorzata; Markowska-Daniel, Iwona; Pejsak, Zygmunt

2012-10-12

In the present study acute phase proteins (APPs) responses in pigs after subclinical infection with H1N1 swine influenza virus (SwH1N1) were evaluated. Fourteen 5 weeks old, seronegative piglets, both sexes were used. Ten of them were infected intranasally with SwH1N1. C-reactive protein (CRP), haptoglobin (Hp), serum amyloid A (SAA) and pig major acute phase protein (Pig-MAP) concentrations in serum were measured using commercial ELISAs. No significant clinical signs were observed in any of the infected pigs, however, all infected animals developed specific antibodies against SwH1N1 and viral shedding was observed from 2 to 5 dpi. Only concentrations of Hp and SAA were significantly induced after infection, with mean maximum levels from days 1 to 2 post infection (dpi). The concentrations of CRP and Pig-MAP remained generally unchanged, however in half of infected pigs the concentration of CRP tended to increase at 1 dpi (but without statistical significance). The results of our study confirmed that monitoring of APPs may be useful for detection of subclinically infected pigs. The use of SAA or Hp and Pig-MAP may be a valuable in combination [i.e. Hp (increased concentration) and Pig-MAP (unchanged concentration)] to detect subclinically SIV infected pigs, or to identify pigs actually producing a large amount of virus. Additional studies need to be done in order to confirm these findings. Copyright © 2012 Elsevier B.V. All rights reserved.

A(H1N1)pdm09 influenza infection: vaccine inefficiency.

PubMed

Friedman, Nehemya; Drori, Yaron; Pando, Rakefet; Glatman-Freedman, Aharona; Sefty, Hanna; Bassal, Ravit; Stein, Yaniv; Shohat, Tamy; Mendelson, Ella; Hindiyeh, Musa; Mandelboim, Michal

2017-05-16

The last influenza pandemic, caused by the swine A(H1N1)pdm09 influenza virus, began in North America at 2009. Since then, the World Health Organization (WHO) recommended integration of the swine-based virus A/California/07/2009 strain in yearly vaccinations. Yet, infections with A(H1N1)pdm09 have continued in subsequent years. The reasons for this are currently unknown. During the 2015-2016 influenza season, we noted an increased prevalence of A(H1N1)pdm09 influenza virus infection in Israel. Our phylogenetic analysis indicated that the circulating A(H1N1)pdm09 strains belonged to 6B.1 and 6B.2 clades and differed from the vaccinating strain, with approximately 18 amino acid differences found between the circulating strains and the immunizing A/California/07/2009 strain. Hemmaglutination inhibition (HI) assays demonstrated higher antibodies titer against the A/California/07/2009 vaccinating strain as compared to the circulating Israeli strains. We thus suggest that the current vaccination was not sufficiently effective and propose inclusion of the current circulating A(H1N1)pdm09 influenza viruses in the annual vaccine composition.

Comparison of two H1N2 swine influenza A viruses from disease outbreaks in pigs in Sweden during 2009 and 2010.

PubMed

Metreveli, Giorgi; Emmoth, Eva; Zohari, Siamak; Bálint, Adám; Widén, Frederik; Muradrasoli, Shaman; Wallgren, Per; Belák, Sándor; Leblanc, Neil; Berg, Mikael; Kiss, István

2011-04-01

The influenza A virus subtypes H1N1, H1N2 and H3N2 are prevalent in pig populations worldwide. In the present study, two relatively uncommon swine influenza virus (SIV) H1N2 subtypes, isolated in Sweden in 2009 and 2010, were compared regarding their molecular composition and biological characteristics. The differences regarding markers purportedly related to pathogenicity, host adaptation or replication efficiency. They included a truncated PB1-F2 protein in the earlier isolate but a full length version in the more recent one; differences in the number of haemagglutinin glycosylation sites, including a characteristic human one; and a nuclear export protein with altered export signal. Of particular interest, the NS1 amino acid sequence of swine H1N2-2009 and 2010 has a 'unique or very unusual' PDZ binding domain (RPKV) at the C-terminal of the protein, a motif that has been implicated as a virulence marker. Concerning biological properties, these viruses reached lower titre and showed reduced cytopathogenicity in MDCK cells compared with an avian-like H1N1 isolate A/swine/Lidkoping/1193/2002 belonging to the same lineage as the 2009 and 2010 isolates. The findings should contribute to better understanding of factors related to the survival/extinction of this uncommon reassortant variant.

Epidemics and the politics of knowledge: contested narratives in Egypt's H1N1 response.

PubMed

Leach, Melissa; Tadros, Mariz

2014-01-01

This article explores the politics of knowledge involved in understanding and responding to epidemics in an era of global health governance and biosecurity. It develops and applies an approach focused on how multiple, competing narratives about epidemics are constructed, mobilized and interact, and selectively justify pathways of intervention and response. A detailed ethnographic case study of national and local responses to H1N1 influenza, so-called swine flu, in Egypt reveals how global narratives were reworked by powerful actors in a particular political context, suppressing and delegitimizing the alternative narratives of the Zabaleen (Coptic Christian) people whose lives and livelihoods centered on raising pigs and working with them to control urban waste. The case study illustrates important ways in which geographies and politics of blame around epidemics emerge and are justified, their political contexts and consequences, and how they may feed back to shape the dynamics of disease itself.

Factors Mediating Seasonal and Influenza A (H1N1) Vaccine Acceptance among Ethnically Diverse Populations in the Urban South

PubMed Central

Frew, Paula M.; Painter, Julia E.; Hixson, Brooke; Kulb, Carolyn; Moore, Kathryn; del Rio, Carlos; Esteves-Jaramillo, Alejandra; Omer, Saad B.

2012-01-01

Objective We examined the acceptability of the influenza A (H1N1) and seasonal vaccinations immediately following government manufacture approval to gauge potential product uptake in minority communities. We studied correlates of vaccine acceptance including attitudes, beliefs, perceptions, and influenza immunization experiences, and sought to identify communication approaches to increase influenza vaccine coverage in community settings. Methods Adults ≥ 18 years participated in a cross-sectional survey from September through December 2009. Venue-based sampling was used to recruit participants of racial and ethnic minorities. Results The sample (N=503) included mostly lower income (81.9%, n=412) participants and African Americans (79.3%, n=399). Respondents expressed greater acceptability of the H1N1 vaccination compared to seasonal flu immunization (t=2.86, p=0.005) although H1N1 vaccine acceptability was moderately low (38%, n=191). Factors associated with acceptance of the H1N1 vaccine included positive attitudes about immunizations [OR=0.23, CI (0.16, 0.33)], community perceptions of H1N1 [OR=2.15, CI (1.57, 2.95)], and having had a flu shot in the past 5 years [OR=2.50, CI (1.52, 4.10). The factors associated with acceptance of the seasonal flu vaccine included positive attitudes about immunization [OR=0.43, CI (0.32, 0.59)], community perceptions of H1N1 [OR=1.53, CI (1.16, 2.01)], and having had the flu shot in the past 5 years [OR=3.53, CI (2.16, 5.78)]. Participants were most likely to be influenced to take a flu shot by physicians [OR=1.94, CI (1.31, 2.86)]. Persons who obtained influenza vaccinations indicated that Facebook (χ2=11.7, p=.02) and Twitter (χ2=18.1, p=.001) could be useful vaccine communication channels and that churches (χ2=21.5, p<.001) and grocery stores (χ2=21.5, p<.001) would be effective “flu shot stops” in their communities. Conclusions In this population, positive vaccine attitudes and community perceptions, along with

Retrospective swine influenza serological surveillance in the four highest pig density provinces of Thailand before the introduction of the 2009 pandemic Influenza A virus subtype H1N1 using various antibody detection assays.

PubMed

Sreta, Donruethai; Jittimanee, Suphattra; Charoenvisal, Nataya; Amonsin, Alongkorn; Kitikoon, Pravina; Thanawongnuwech, Roongroje

2013-01-01

Genetic characterization of the hemagglutinin gene of the 6 selected Thai Swine influenza virus (SIV) isolates (4 H1 and 2 H3 isolates) used in the establishment of a hemagglutination inhibition (HI) assay was analyzed. Based on the phylogenetic analysis, Thai SIVs could be divided into 3 clusters of the H1 viruses (clusters I and II belonging to classical swine H1α, and cluster III belonging to classical swine H1γ), and 2 clusters of the H3 viruses both belonging to human-like 1970s. The serological results indicated that swH1N1-06 (H1 cluster I) is a suitable representative SIV for the HI test antigen to detect H1 SIV-specific antibodies in the Thai swine population, while both swH3N2-05 and swH3N2-07 should be used for Thai H3 SIV-specific antibody detection. The HI test results of swine sera collected from pigs in the 4 highest pig population provinces of Thailand indicated that the percentage of pigs seropositive to swH3N2-07 was highest compared to swH1N1-06, swH1N1-09, and swH3N2-05 (85.4%, 50.1%, 18.6%, and 15.8%, respectively). It should be noted that countries lacking SIV genetic information should be concerned with determining the most suitable HI test antigens to use when performing the tests due to the genetic variation and limited cross-reaction of SIVs. The results of the current study demonstrated that HI tests should be implemented with the suitable field strains as the representative test antigen to ascertain accurate SIV serostatus in Thailand and that test antigens should be genetically analyzed and compared with circulating strains regularly.

Pathogenic characteristics of a novel triple-reasserted H1N2 swine influenza virus.

PubMed

Liu, Huili; Tao, Jie; Zhang, Pengchao; Yin, Xiuchen; Ha, Zhuo; Zhang, Chunling

2016-07-01

A novel triple reasserted H1N2 virus A/swine/Shanghai/1/2007 (SH07) was isolated from nasal swabs of weaned pig showing clinical symptoms of coughing and sneezing. To explore the virus characteristics, mice, chickens and pigs were selected for pathogenicity study. Pigs inoculated intranasally with 10(6) TCID50 SH07 showed clinical symptoms with coughing and sneezing, but no death. The virus nuclear acid was detected in many tissues using real-time PCR, which was mainly distributed in respiratory system particularly in the lungs. The virus was low-pathogenic to chickens with 10(6) TCID50 dose inoculation either via intramuscular or intranasal routes. However virus nuclear acid detection and virus isolation confirmed that the virus can also be found in nasal and rectum. When virus was inoculated into mice by intramuscular or intranasal routes we observed 100% and 80% lethality respectively. The third generation of samples passaged on MDCK cell were SIV positive in indirect immunofluorescence assay (IFA) using antiserum against H1N2 SIV. Furthermore, the lungs of mice showed obvious lesion with interstitial pneumonia. Data in our study suggest that SH07 is preferentially pathogenic to mammals rather than birds although it is a reasserting virus with the fragments from swine, human and avian origin. Copyright © 2016 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

Human T-cells directed to seasonal influenza A virus cross-react with 2009 pandemic influenza A (H1N1) and swine-origin triple-reassortant H3N2 influenza viruses.

PubMed

Hillaire, Marine L B; Vogelzang-van Trierum, Stella E; Kreijtz, Joost H C M; de Mutsert, Gerrie; Fouchier, Ron A M; Osterhaus, Albert D M E; Rimmelzwaan, Guus F

2013-03-01

Virus-specific CD8(+) T-cells contribute to protective immunity against influenza A virus (IAV) infections. As the majority of these cells are directed to conserved viral proteins, they may afford protection against IAVs of various subtypes. The present study assessed the cross-reactivity of human CD8(+) T-lymphocytes, induced by infection with seasonal A (H1N1) or A (H3N2) influenza virus, with 2009 pandemic influenza A (H1N1) virus [A(H1N1)pdm09] and swine-origin triple-reassortant A (H3N2) [A(H3N2)v] viruses that are currently causing an increasing number of human cases in the USA. It was demonstrated that CD8(+) T-cells induced after seasonal IAV infections exerted lytic activity and produced gamma interferon upon in vitro restimulation with A(H1N1)pdm09 and A(H3N2)v influenza A viruses. Furthermore, CD8(+) T-cells directed to A(H1N1)pdm09 virus displayed a high degree of cross-reactivity with A(H3N2)v viruses. It was concluded that cross-reacting T-cells had the potential to afford protective immunity against A(H1N1)pdm09 viruses during the pandemic and offer some degree of protection against infection with A(H3N2)v viruses.

OpenFluDB, a database for human and animal influenza virus

PubMed Central

Liechti, Robin; Gleizes, Anne; Kuznetsov, Dmitry; Bougueleret, Lydie; Le Mercier, Philippe; Bairoch, Amos; Xenarios, Ioannis

2010-01-01

Although research on influenza lasted for more than 100 years, it is still one of the most prominent diseases causing half a million human deaths every year. With the recent observation of new highly pathogenic H5N1 and H7N7 strains, and the appearance of the influenza pandemic caused by the H1N1 swine-like lineage, a collaborative effort to share observations on the evolution of this virus in both animals and humans has been established. The OpenFlu database (OpenFluDB) is a part of this collaborative effort. It contains genomic and protein sequences, as well as epidemiological data from more than 27 000 isolates. The isolate annotations include virus type, host, geographical location and experimentally tested antiviral resistance. Putative enhanced pathogenicity as well as human adaptation propensity are computed from protein sequences. Each virus isolate can be associated with the laboratories that collected, sequenced and submitted it. Several analysis tools including multiple sequence alignment, phylogenetic analysis and sequence similarity maps enable rapid and efficient mining. The contents of OpenFluDB are supplied by direct user submission, as well as by a daily automatic procedure importing data from public repositories. Additionally, a simple mechanism facilitates the export of OpenFluDB records to GenBank. This resource has been successfully used to rapidly and widely distribute the sequences collected during the recent human swine flu outbreak and also as an exchange platform during the vaccine selection procedure. Database URL: http://openflu.vital-it.ch. PMID:20624713