WorldWideScience

Sample records for h1n1 influenza pandemic

  1. Pandemic influenza A (H1N1)

    African Journals Online (AJOL)

    ... in Port Shepstone, South Africa. Introduction. Influenza A (H1N1) 2009 'swine flu' variant is currently a global pandemic.1 The infection associated with this virus is usually a mild, self-limiting illness. However, it may progress to severe pneumonia requiring intensive care unit (ICU) therapy in 31% of patients.2 This may.

  2. Epidemiological characteristics of Pandemic Influenza A (H1N1 ...

    African Journals Online (AJOL)

    Background: A novel influenza A virus strain (H1N1-2009) spread first in Mexico and the United Stated in late April 2009, leading to the first influenza pandemic of the 21st century. The objective of this study was to determine the epidemiological and virological characteristics of the pandemic influenza A (H1N1-2009) in ...

  3. Epidemiological characteristics of Pandemic Influenza A (H1N1 ...

    African Journals Online (AJOL)

    ... novel influenza A virus strain (H1N1-2009) spread first in Mexico and the United Stated in late April 2009, leading to the first influenza pandemic of the 21st century. The objective of this study was to determine the epidemiological and virological characteristics of the pandemic influenza A (H1N1-2009) in Zhanjiang, China ...

  4. Treatment and Prevention of Pandemic H1N1 Influenza.

    Science.gov (United States)

    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.

  5. Outbreak of pandemic influenza A/H1N1 2009 in Nepal.

    Science.gov (United States)

    Adhikari, Bal Ram; Shakya, Geeta; Upadhyay, Bishnu Prasad; Prakash Kc, Khagendra; Shrestha, Sirjana Devi; Dhungana, Guna Raj

    2011-03-23

    The 2009 flu pandemic is a global outbreak of a new strain of H1N1 influenza virus. Pandemic influenza A (H1N1) 2009 has posed a serious public health challenge world-wide. Nepal has started Laboratory diagnosis of Pandemic influenza A/H1N1 from mid June 2009 though active screening of febrile travellers with respiratory symptoms was started from April 27, 2009. Out of 609 collected samples, 302 (49.6%) were Universal Influenza A positive. Among the influenza A positive samples, 172(28.3%) were positive for Pandemic influenza A/H1N1 and 130 (21.3%) were Seasonal influenza A. Most of the pandemic cases (53%) were found among young people with ≤ 20 years. Case Fatality Ratio for Pandemic influenza A/H1N1 in Nepal was 1.74%. Upon Molecular characterization, all the isolated pandemic influenza A/H1N1 2009 virus found in Nepal were antigenically and genetically related to the novel influenza A/CALIFORNIA/07/2009-LIKE (H1N1)v type. The Pandemic 2009 influenza virus found in Nepal were antigenically and genetically related to the novel A/CALIFORNIA/07/2009-LIKE (H1N1)v type.

  6. Outbreak of pandemic influenza A/H1N1 2009 in Nepal

    Directory of Open Access Journals (Sweden)

    Shrestha Sirjana

    2011-03-01

    Full Text Available Abstract Background The 2009 flu pandemic is a global outbreak of a new strain of H1N1 influenza virus. Pandemic influenza A (H1N1 2009 has posed a serious public health challenge world-wide. Nepal has started Laboratory diagnosis of Pandemic influenza A/H1N1 from mid June 2009 though active screening of febrile travellers with respiratory symptoms was started from April 27, 2009. Results Out of 609 collected samples, 302 (49.6% were Universal Influenza A positive. Among the influenza A positive samples, 172(28.3% were positive for Pandemic influenza A/H1N1 and 130 (21.3% were Seasonal influenza A. Most of the pandemic cases (53% were found among young people with ≤ 20 years. Case Fatality Ratio for Pandemic influenza A/H1N1 in Nepal was 1.74%. Upon Molecular characterization, all the isolated pandemic influenza A/H1N1 2009 virus found in Nepal were antigenically and genetically related to the novel influenza A/CALIFORNIA/07/2009-LIKE (H1N1v type. Conclusion The Pandemic 2009 influenza virus found in Nepal were antigenically and genetically related to the novel A/CALIFORNIA/07/2009-LIKE (H1N1v type.

  7. Characteristics of atopic children with pandemic H1N1 influenza viral infection: pandemic H1N1 influenza reveals 'occult' asthma of childhood.

    Science.gov (United States)

    Hasegawa, Shunji; Hirano, Reiji; Hashimoto, Kunio; Haneda, Yasuhiro; Shirabe, Komei; Ichiyama, Takashi

    2011-02-01

    The number of human cases of pandemic H1N1 influenza viral infection has increased in Japan since April 2009, as it has worldwide. This virus is widespread in the Yamaguchi prefecture in western Japan, where most infected children exhibited respiratory symptoms. Bronchial asthma is thought to be one of the risk factors that exacerbate respiratory symptoms of pandemic H1N1-infected patients, but the pathogenesis remains unclear. We retrospectively investigated the records of 33 children with pandemic H1N1 influenza viral infection who were admitted to our hospital between October and December 2009 and analyzed their clinical features. The percentage of children with asthma attack, with or without abnormal findings on chest radiographs (pneumonia, atelectasis, etc.), caused by pandemic H1N1 influenza infection was significantly higher than that of children with asthma attack and 2008-2009 seasonal influenza infection. Of the 33 children in our study, 22 (66.7%) experienced an asthma attack. Among these children, 20 (90.9%) did not receive long-term management for bronchial asthma, whereas 7 (31.8%) were not diagnosed with bronchial asthma and had experienced their first asthma attack. However, the severity of the attack did not correlate with the severity of the pulmonary complications of pandemic H1N1 influenza viral infection. The pandemic H1N1 influenza virus greatly increases the risk of lower respiratory tract complications such as asthma attack, pneumonia, and atelectasis, when compared to the seasonal influenza virus. Furthermore, our results suggest that pandemic H1N1 influenza viral infection can easily induce a severe asthma attack, pneumonia, and atelectasis in atopic children without any history of either an asthma attack or asthma treatment. © 2011 John Wiley & Sons A/S.

  8. Pediatric Healthcare Response to Pandemic (H1N1) 2009 Influenza Stakeholder Meeting - Summary of Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    HCTT CHE

    2010-01-01

    The goal of the meeting was to bring together subject matter experts to develop tools and resources for use by the pediatric healthcare community in response to 2009 (H1N1) pandemic influenza activity during the 2009 influenza season.

  9. Adoption of Preventive Measures and Attitudes toward the H1N1 Influenza Pandemic in Schools

    Science.gov (United States)

    Pérez, Anna; Rodríguez, Tània; López, Maria José; Continente, Xavier; Nebot, Manel

    2016-01-01

    Background: This study describes the perceived impact of H1N1 influenza and the adoption of the recommended measures to address the pandemic in schools. Methods: A cross-sectional self-reported survey was conducted in 433 schools in Barcelona addressed to the school principal or the H1N1 influenza designated person. A descriptive analysis was…

  10. Identification of reassortant pandemic H1N1 influenza virus in Korean pigs.

    Science.gov (United States)

    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.

  11. Clinical outcomes of seasonal influenza and pandemic influenza A (H1N1 in pediatric inpatients

    Directory of Open Access Journals (Sweden)

    Budd Alicia

    2010-10-01

    Full Text Available Abstract Background In April 2009, a novel influenza A H1N1 (nH1N1 virus emerged and spread rapidly worldwide. News of the pandemic led to a heightened awareness of the consequences of influenza and generally resulted in enhanced infection control practices and strengthened vaccination efforts for both healthcare workers and the general population. Seasonal influenza (SI illness in the pediatric population has been previously shown to result in significant morbidity, mortality, and substantial hospital resource utilization. Although influenza pandemics have the possibility of resulting in considerable illness, we must not ignore the impact that we can experience annually with SI. Methods We compared the outcomes of pediatric patients ≤18 years of age at a large urban hospital with laboratory confirmed influenza and an influenza-like illness (ILI during the 2009 pandemic and two prior influenza seasons. The primary outcome measure was hospital length of stay (LOS. All variables potentially associated with LOS based on univariable analysis, previous studies, or hypothesized relationships were included in the regression models to ensure adjustment for their effects. Results There were 133 pediatric cases of nH1N1 admitted during 2009 and 133 cases of SI admitted during the prior 2 influenza seasons (2007-8 and 2008-9. Thirty-six percent of children with SI and 18% of children with nH1N1 had no preexisting medical conditions (p = 0.14. Children admitted with SI had 1.73 times longer adjusted LOS than children admitted for nH1N1 (95% CI 1.35 - 2.13. There was a trend towards more children with SI requiring mechanical ventilation compared with nH1N1 (16 vs.7, p = 0.08. Conclusions This study strengthens the growing body of evidence demonstrating that SI results in significant morbidity in the pediatric population. Pandemic H1N1 received considerable attention with strong media messages urging people to undergo vaccination and encouraging improved

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  14. Hospitalizations Associated with Pandemic Influenza A (H1N1) 2009 in Asthmatic Children in Japan

    OpenAIRE

    Toshio Katsunuma; Takehiko Matsui; Tsutomu Iwata; Mitsuhiko Nambu; Naomi Kondo

    2012-01-01

    Background: The pandemic influenza A (H1N1) 2009 [pdm (H1N1) 2009] spread through the world in 2009, producing a serious epidemic in Japan. Since it was suggested early that asthma is a risk factor for an increased severity of the infection, the Japanese Society of Pediatric Allergy and Clinical Immunology (JSPACI) organized a working group for countermeasures, and investigated asthmatic children admitted to the hospitals for pdm (H1N1) 2009 infection. Methods: An appeal was made on the ho...

  15. Genetic Characterization of Influenza A (H1N1) Pandemic 2009 Virus Isolates from Mumbai.

    Science.gov (United States)

    Gohil, Devanshi; Kothari, Sweta; Shinde, Pramod; Meharunkar, Rhuta; Warke, Rajas; Chowdhary, Abhay; Deshmukh, Ranjana

    2017-08-01

    Pandemic influenza A (H1N1) 2009 virus was first detected in India in May 2009 which subsequently became endemic in many parts of the country. Influenza A viruses have the ability to evade the immune response through its ability of antigenic variations. The study aims to characterize influenza A (H1N1) pdm 09 viruses circulating in Mumbai during the pandemic and post-pandemic period. Nasopharyngeal swabs positive for influenza A (H1N1) pdm 09 viruses were inoculated on Madin-Darby canine kidney cell line for virus isolation. Molecular and phylogenetic analysis of influenza A (H1N1) pdm 09 isolates was conducted to understand the evolution and genetic diversity of the strains. Nucleotide and amino acid sequences of the HA gene of Mumbai isolates when compared to A/California/07/2009-vaccine strain revealed 14 specific amino acid differences located at the antigenic sites. Amino acid variations in HA and NA gene resulted in changes in the N-linked glycosylation motif which may lead to immune evasion. Phylogenetic analysis of the isolates revealed their evolutionary position with vaccine strain A/California/07/2009 but had undergone changes gradually. The findings in the present study confirm genetic variability of influenza viruses and highlight the importance of continuous surveillance during influenza outbreaks.

  16. Evolution and adaptation of the pandemic A/H1N1 2009 influenza virus

    Directory of Open Access Journals (Sweden)

    Ducatez MF

    2011-07-01

    Full Text Available Mariette F Ducatez, Thomas P Fabrizio, Richard J WebbyDepartment of Infectious Diseases, St Jude Children's Research Hospital, Memphis, TN, USAAbstract: The emergence of the 2009 H1N1 pandemic influenza virus [A(H1N1pdm09] has provided the public health community with many challenges, but also the scientific community with an opportunity to monitor closely its evolution through the processes of drift and shift. To date, and despite having circulated in humans for nearly two years, little antigenic variation has been observed in the A(H1N1pdm09 viruses. However, as the A(H1N1pdm09 virus continues to circulate and the immunologic pressure within the human population increases, future antigenic change is almost a certainty. Several coinfections of A(H1N1pdm09 and seasonal A(H1N1 or A(H3N2 viruses have been observed, but no reassortant viruses have been described in humans, suggesting a lack of fitness of reassortant viruses or a lack of opportunities for interaction of different viral lineages. In contrast, multiple reassortment events have been detected in swine populations between A(H1N1 pdm09 and other endemic swine viruses. Somewhat surprisingly, many of the well characterized influenza virus virulence markers appear to have limited impact on the phenotype of the A(H1N1pdm09 viruses when they have been introduced into mutant viruses in laboratory settings. As such, it is unclear what the evolutionary path of the pandemic virus will be, but the monitoring of any changes in the circulating viruses will remain a global public and animal health priority.Keywords: influenza, pandemic, evolution, adaptation

  17. Pandemic influenza A/H1N1 virus incursion into Africa: countries ...

    African Journals Online (AJOL)

    Pandemic influenza A/H1N1 virus incursion into Africa: countries, hosts and ... features are important for planning control measures between countries and to ... in humans, infections in pigs earlier reported in America, Europe and Asia were ...

  18. Comparative analyses of pandemic H1N1 and seasonal H1N1, H3N2, and influenza B infections depict distinct clinical pictures in ferrets.

    Directory of Open Access Journals (Sweden)

    Stephen S H Huang

    Full Text Available Influenza A and B infections are a worldwide health concern to both humans and animals. High genetic evolution rates of the influenza virus allow the constant emergence of new strains and cause illness variation. Since human influenza infections are often complicated by secondary factors such as age and underlying medical conditions, strain or subtype specific clinical features are difficult to assess. Here we infected ferrets with 13 currently circulating influenza strains (including strains of pandemic 2009 H1N1 [H1N1pdm] and seasonal A/H1N1, A/H3N2, and B viruses. The clinical parameters were measured daily for 14 days in stable environmental conditions to compare clinical characteristics. We found that H1N1pdm strains had a more severe physiological impact than all season strains where pandemic A/California/07/2009 was the most clinically pathogenic pandemic strain. The most serious illness among seasonal A/H1N1 and A/H3N2 groups was caused by A/Solomon Islands/03/2006 and A/Perth/16/2009, respectively. Among the 13 studied strains, B/Hubei-Wujiagang/158/2009 presented the mildest clinical symptoms. We have also discovered that disease severity (by clinical illness and histopathology correlated with influenza specific antibody response but not viral replication in the upper respiratory tract. H1N1pdm induced the highest and most rapid antibody response followed by seasonal A/H3N2, seasonal A/H1N1 and seasonal influenza B (with B/Hubei-Wujiagang/158/2009 inducing the weakest response. Our study is the first to compare the clinical features of multiple circulating influenza strains in ferrets. These findings will help to characterize the clinical pictures of specific influenza strains as well as give insights into the development and administration of appropriate influenza therapeutics.

  19. Anti-pandemic influenza A (H1N1) virus potential of catechin and gallic acid.

    Science.gov (United States)

    You, Huey-Ling; Huang, Chao-Chun; Chen, Chung-Jen; Chang, Cheng-Chin; Liao, Pei-Lin; Huang, Sheng-Teng

    2018-05-01

    The pandemic influenza A (H1N1) virus has spread worldwide and infected a large proportion of the human population. Discovery of new and effective drugs for the treatment of influenza is a crucial issue for the global medical community. According to our previous study, TSL-1, a fraction of the aqueous extract from the tender leaf of Toonasinensis, has demonstrated antiviral activities against pandemic influenza A (H1N1) through the down-regulation of adhesion molecules and chemokine to prevent viral attachment. The aim of the present study was to identify the active compounds in TSL-1 which exert anti-influenza A (H1N1) virus effects. XTT assay was used to detect the cell viability. Meanwhile, the inhibitory effect on the pandemic influenza A (H1N1) virus was analyzed by observing plaque formation, qRT-PCR, neuraminidase activity, and immunofluorescence staining of influenza A-specific glycoprotein. Both catechin and gallic acid were found to be potent inhibitors in terms of influenza virus mRNA replication and MDCK plaque formation. Additionally, both compounds inhibited neuraminidase activities and viral glycoprotein. The 50% effective inhibition concentration (EC 50 ) of catechin and gallic acid for the influenza A (H1N1) virus were 18.4 μg/mL and 2.6 μg/mL, respectively; whereas the 50% cytotoxic concentrations (CC 50 ) of catechin and gallic acid were >100 μg/mL and 22.1 μg/mL, respectively. Thus, the selectivity indexes (SI) of catechin and gallic acid were >5.6 and 22.1, respectively. The present study demonstrates that catechin might be a safe reagent for long-term use to prevent influenza A (H1N1) virus infection; whereas gallic acid might be a sensitive reagent to inhibit influenza virus infection. We conclude that these two phyto-chemicals in TSL-1 are responsible for exerting anti-pandemic influenza A (H1N1) virus effects. Copyright © 2017. Published by Elsevier Taiwan LLC.

  20. Supply of neuraminidase inhibitors related to reduced influenza A (H1N1) mortality during the 2009-2010 H1N1 pandemic: an ecological study.

    Science.gov (United States)

    Miller, Paula E; Rambachan, Aksharananda; Hubbard, Roderick J; Li, Jiabai; Meyer, Alison E; Stephens, Peter; Mounts, Anthony W; Rolfes, Melissa A; Penn, Charles R

    2012-01-01

    The influenza A (H1N1) pandemic swept across the globe from April 2009 to August 2010 affecting millions. Many WHO Member States relied on antiviral drugs, specifically neuraminidase inhibitors (NAIs) oseltamivir and zanamivir, to treat influenza patients in critical condition. Such drugs have been found to be effective in reducing severity and duration of influenza illness, and likely reduced morbidity during the pandemic. However, it is less clear whether NAIs used during the pandemic reduced H1N1 mortality. Country-level data on supply of oseltamivir and zanamivir were used to predict H1N1 mortality (per 100,000 people) from July 2009 to August 2010 in forty-two WHO Member States. Poisson regression was used to model the association between NAI supply and H1N1 mortality, with adjustment for economic, demographic, and health-related confounders. After adjustment for potential confounders, each 10% increase in kilograms of oseltamivir, per 100,000 people, was associated with a 1.6% reduction in H1N1 mortality over the pandemic period (relative rate (RR) = 0.84 per log increase in oseltamivir supply). While the supply of zanamivir was considerably less than that of oseltamivir in each Member State, each 10% increase in kilogram of active zanamivir, per 100,000, was associated with a 0.3% reduction in H1N1 mortality (RR = 0.97 per log increase). While there are limitations to the ecologic nature of these data, this analysis offers evidence of a protective relationship between antiviral drug supply and influenza mortality and supports a role for influenza antiviral use in future pandemics.

  1. The seroprevalence of pandemic influenza H1N1 (2009 virus in China.

    Directory of Open Access Journals (Sweden)

    Cuiling Xu

    2011-04-01

    Full Text Available Mainland China experienced pandemic influenza H1N1 (2009 virus (pH1N1 with peak activity during November-December 2009. To understand the geographic extent, risk factors, and attack rate of pH1N1 infection in China we conducted a nationwide serological survey to determine the prevalence of antibodies to pH1N1.Stored serum samples (n = 2,379 collected during 2006-2008 were used to estimate baseline serum reactogenicity to pH1N1. In January 2010, we used a multistage-stratified random sampling method to select 50,111 subjects who met eligibility criteria and collected serum samples and administered a standardized questionnaire. Antibody response to pH1N1 was measured using haemagglutination inhibition (HI assay and the weighted seroprevalence was calculated using the Taylor series linearization method. Multivariable logistic regression analyses were used to examine risk factors for pH1N1 seropositivity. Baseline seroprevalence of pH1N1 antibody (HI titer ≥40 was 1.2%. The weighted seroprevalence of pH1N1 among the Chinese population was 21.5%(vaccinated: 62.0%; unvaccinated: 17.1%. Among unvaccinated participants, those aged 6-15 years (32.9% and 16-24 years (30.3% had higher seroprevalence compared with participants aged 25-59 years (10.7% and ≥60 years (9.9%, P<0.0001. Children in kindergarten and students had higher odds of seropositivity than children in family care (OR: 1.36 and 2.05, respectively. We estimated that 207.7 million individuals (15.9% experienced pH1N1 infection in China.The Chinese population had low pre-existing immunity to pH1N1 and experienced a relatively high attack rate in 2009 of this virus. We recommend routine control measures such as vaccination to reduce transmission and spread of seasonal and pandemic influenza viruses.

  2. Effect of priming with H1N1 influenza viruses of variable antigenic distances on challenge with 2009 pandemic H1N1 virus.

    Science.gov (United States)

    O'Donnell, Christopher D; Wright, Amber; Vogel, Leatrice N; Wei, Chih-Jen; Nabel, Gary J; Subbarao, Kanta

    2012-08-01

    Compared to seasonal influenza viruses, the 2009 pandemic H1N1 (pH1N1) virus caused greater morbidity and mortality in children and young adults. People over 60 years of age showed a higher prevalence of cross-reactive pH1N1 antibodies, suggesting that they were previously exposed to an influenza virus or vaccine that was antigenically related to the pH1N1 virus. To define the basis for this cross-reactivity, ferrets were infected with H1N1 viruses of variable antigenic distance that circulated during different decades from the 1930s (Alaska/35), 1940s (Fort Monmouth/47), 1950s (Fort Warren/50), and 1990s (New Caledonia/99) and challenged with 2009 pH1N1 virus 6 weeks later. Ferrets primed with the homologous CA/09 or New Jersey/76 (NJ/76) virus served as a positive control, while the negative control was an influenza B virus that should not cross-protect against influenza A virus infection. Significant protection against challenge virus replication in the respiratory tract was observed in ferrets primed with AK/35, FM/47, and NJ/76; FW/50-primed ferrets showed reduced protection, and NC/99-primed ferrets were not protected. The hemagglutinins (HAs) of AK/35, FM/47, and FW/50 differ in the presence of glycosylation sites. We found that the loss of protective efficacy observed with FW/50 was associated with the presence of a specific glycosylation site. Our results suggest that changes in the HA occurred between 1947 and 1950, such that prior infection could no longer protect against 2009 pH1N1 infection. This provides a mechanistic understanding of the nature of serological cross-protection observed in people over 60 years of age during the 2009 H1N1 pandemic.

  3. Fitness of Pandemic H1N1 and Seasonal influenza A viruses during Co-infection: Evidence of competitive advantage of pandemic H1N1 influenza versus seasonal influenza.

    Science.gov (United States)

    Perez, Daniel Roberto; Sorrell, Erin; Angel, Matthew; Ye, Jianqiang; Hickman, Danielle; Pena, Lindomar; Ramirez-Nieto, Gloria; Kimble, Brian; Araya, Yonas

    2009-08-24

    On June 11, 2009 the World Health Organization (WHO) declared a new H1N1 influenza pandemic. This pandemic strain is as transmissible as seasonal H1N1 and H3N2 influenza A viruses. Major concerns facing this pandemic are whether the new virus will replace, co-circulate and/or reassort with seasonal H1N1 and/or H3N2 human strains. Using the ferret model, we investigated which of these three possibilities were most likely favored. Our studies showed that the current pandemic virus is more transmissible than, and has a biological advantage over, prototypical seasonal H1 or H3 strains.

  4. THE A (H1N1 INFLUENZA. SYMBOLIC DIMENSIONS OF A PANDEMIC ARTEFACT

    Directory of Open Access Journals (Sweden)

    Andrés G. Seguel

    2013-01-01

    Full Text Available The aim of the present paper is to present the symbolic features that are exposed by the concept of artefact in the context of a pandemic alarm, such as the A (H1N1 influenza. The symbolic qualities entailed by the notion of artefact are well-known within the Social Sciences: Sociology, Anthropology, Archaeology, and Linguistics. The artefact is basically not an object, but an action aimed at designing, simulating or creating a simile by means of material, technological or linguistic structures. The purpose of the present work is to unveil the symbolic dimensions that are activated by the A (H1N1 influenza as a Pandemic Artefact: a the assumption of separating information from matter; b the need for a material support to enable the exchange; c the sociological reflexivity of the artefact and its agency; d the arbitrariness of its social use, that detaches it from the design as intention.

  5. Efficacy of a pandemic (H1N1) 2009 virus vaccine in pigs against the pandemic influenza virus is superior to commercially available swine influenza vaccines.

    NARCIS (Netherlands)

    Loeffen, W.L.A.; Stockhofe-Zurwieden, N.; Weesendorp, E.; Zoelen-Bos, van D.J.; Heutink, R.; Quak, J.; Goovaerts, D.; Heldens, J.; Maas, H.A.; Moormann, R.J.M.; Koch, G.

    2011-01-01

    In April 2009 a new influenza A/H1N1 strain, currently named “pandemic (H1N1) influenza 2009¿ (H1N1v), started the first official pandemic in humans since 1968. Several incursions of this virus in pig herds have also been reported from all over the world. Vaccination of pigs may be an option to

  6. The transmissibility and control of pandemic influenza A (H1N1) virus.

    Science.gov (United States)

    Yang, Yang; Sugimoto, Jonathan D; Halloran, M Elizabeth; Basta, Nicole E; Chao, Dennis L; Matrajt, Laura; Potter, Gail; Kenah, Eben; Longini, Ira M

    2009-10-30

    Pandemic influenza A (H1N1) 2009 (pandemic H1N1) is spreading throughout the planet. It has become the dominant strain in the Southern Hemisphere, where the influenza season has now ended. Here, on the basis of reported case clusters in the United States, we estimated the household secondary attack rate for pandemic H1N1 to be 27.3% [95% confidence interval (CI) from 12.2% to 50.5%]. From a school outbreak, we estimated that a typical schoolchild infects 2.4 (95% CI from 1.8 to 3.2) other children within the school. We estimated the basic reproductive number, R0, to range from 1.3 to 1.7 and the generation interval to range from 2.6 to 3.2 days. We used a simulation model to evaluate the effectiveness of vaccination strategies in the United States for fall 2009. If a vaccine were available soon enough, vaccination of children, followed by adults, reaching 70% overall coverage, in addition to high-risk and essential workforce groups, could mitigate a severe epidemic.

  7. Heterogeneous virulence of pandemic 2009 influenza H1N1 virus in mice

    Directory of Open Access Journals (Sweden)

    Farooqui Amber

    2012-06-01

    Full Text Available Abstract Background Understanding the pathogenesis of influenza infection is a key factor leading to the prevention and control of future outbreaks. Pandemic 2009 Influenza H1N1 infection, although frequently mild, led to a severe and fatal form of disease in certain cases that make its virulence nature debatable. Much effort has been made toward explaining the determinants of disease severity; however, no absolute reason has been established. Results This study presents the heterogeneous virulence of clinically similar strains of pandemic 2009 influenza virus in human alveolar adenocarcinoma cells and mice. The viruses were obtained from patients who were admitted in a local hospital in China with a similar course of infection and recovered. The A/Nanchang/8002/2009 and A/Nanchang/8011/2009 viruses showed efficient replication and high lethality in mice while infection with A/Nanchang/8008/2009 was not lethal with impaired viral replication, minimal pathology and modest proinflammatory activity in lungs. Sequence analysis displayed prominent differences between polymerase subunits (PB2 and PA of viral genomes that might correlate with their different phenotypic behavior. Conclusions The study confirms that biological heterogeneity, linked with the extent of viral replication, exists among pandemic H1N1 strains that may serve as a benchmark for future investigations on influenza pathogenesis.

  8. Pandemic influenza A/H1N1pdm in Italy: age, risk and population susceptibility.

    Directory of Open Access Journals (Sweden)

    Stefano Merler

    Full Text Available BACKGROUND: A common pattern emerging from several studies evaluating the impact of the 2009 A/H1N1 pandemic influenza (A/H1N1pdm conducted in countries worldwide is the low attack rate observed in elderly compared to that observed in children and young adults. The biological or social mechanisms responsible for the observed age-specific risk of infection are still to be deeply investigated. METHODS: The level of immunity against the A/H1N1pdm in pre and post pandemic sera was determined using left over sera taken for diagnostic purposes or routine ascertainment obtained from clinical laboratories. The antibody titres were measured by the haemagglutination inhibition (HI assay. To investigate whether certain age groups had higher risk of infection the presence of protective antibody (≥1∶40, was calculated using exact binomial 95% CI on both pre- and post- pandemic serological data in the age groups considered. To estimate age-specific susceptibility to infection we used an age-structured SEIR model. RESULTS: By comparing pre- and post-pandemic serological data in Italy we found age- specific attack rates similar to those observed in other countries. Cumulative attack rate at the end of the first A/H1N1pdm season in Italy was estimated to be 16.3% (95% CI 9.4%-23.1%. Modeling results allow ruling out the hypothesis that only age-specific characteristics of the contact network and levels of pre-pandemic immunity are responsible for the observed age-specific risk of infection. This means that age-specific susceptibility to infection, suspected to play an important role in the pandemic, was not only determined by pre-pandemic levels of H1N1pdm antibody measured by HI. CONCLUSIONS: Our results claim for new studies to better identify the biological mechanisms, which might have determined the observed pattern of susceptibility with age. Moreover, our results highlight the need to obtain early estimates of differential susceptibility with age in

  9. Fulminant hemophagocytic lymphohistiocytosis induced by pandemic A (H1N1 influenza: a case report

    Directory of Open Access Journals (Sweden)

    Wacrenier Agnès

    2011-07-01

    Full Text Available Abstract Introduction Hemophagocytic lymphohistiocytosis induced by viral diseases is a well recognized entity. Severe forms of H5N1 influenza are known to be associated with symptoms very similar to a reactive hemophagocytic syndrome. We report a case of fulminant lymphohistiocytosis associated with the pandemic A (H1N1 variant. Case presentation A 42-year-old Caucasian woman developed a syndrome of fatal hemophagocytic lymphohistiocytosis shortly after H1N1 influenza. Initial symptoms of the viral disease were unusual, with acute abdominal involvement. Our patient's course was complicated by diffuse skin rash and ileal ischemia. Our patient died of refractory shock and multi-organ failure. Skin, ileum and colon histology was consistent with an acute apoptosis combined with an increased cellular regeneration. Conclusions Influenza may be complicated by severe forms of hemophagocytic lymphohistiocytosis. To ensure early recognition and treatment, physicians should be aware of the possible induction of the syndrome by the novel H1N1 variant. The rapid occurrence of a multi-organ involvement with evocative biological features of macrophage activation should alert clinicians.

  10. The 2009 A (H1N1) influenza virus pandemic: A review.

    Science.gov (United States)

    Girard, Marc P; Tam, John S; Assossou, Olga M; Kieny, Marie Paule

    2010-07-12

    In March and early April 2009 a new swine-origin influenza virus (S-OIV), A (H1N1), emerged in Mexico and the USA. The virus quickly spread worldwide through human-to-human transmission. In view of the number of countries and communities which were reporting human cases, the World Health Organization raised the influenza pandemic alert to the highest level (level 6) on June 11, 2009. The propensity of the virus to primarily affect children, young adults and pregnant women, especially those with an underlying lung or cardiac disease condition, and the substantial increase in rate of hospitalizations, prompted the efforts of the pharmaceutical industry, including new manufacturers from China, Thailand, India and South America, to develop pandemic H1N1 influenza vaccines. All currently registered vaccines were tested for safety and immunogenicity in clinical trials on human volunteers. All were found to be safe and to elicit potentially protective antibody responses after the administration of a single dose of vaccine, including split inactivated vaccines with or without adjuvant, whole-virion vaccines and live-attenuated vaccines. The need for an increased surveillance of influenza virus circulation in swine is outlined. Copyright 2010. Published by Elsevier Ltd.

  11. Comparison between pandemic H1N1 2009 influenza pneumonia and seasonal influenza pneumonia in adults

    International Nuclear Information System (INIS)

    Ishiguro, Takashi; Takayanagi, Noboru; Yoneda, Koichiro

    2011-01-01

    We compared 126 cases of seasonal influenza pneumonia (seasonal flu) reported between January, 1996 and March, 2009, with 10 cases of laboratory-confirmed pandemic influenza (H1N1) 2009 influenza virus pneumonia (novel flu), based on clinical condition, computed tomography (CT) findings, severity, treatment, and prognosis, to clarify the characteristics of this novel flu. The mean age of subjects was 52.4 years in the novel flu group and 64 years in the seasonal flu group, and novel flu patients were younger than seasonal flu patients. Seasonal flu patients had more underlying diseases than did novel flu patients. The median duration from illness onset to hospitalization was 4 days in both groups. Primary viral pneumonia was present in 70% of novel flu cases and 31% of seasonal flu cases. The proportion of primary virus pneumonia was higher in novel flu patients, and the disease severity of the seasonal flu group was more severe than that of the novel flu group. White blood cell and lymphocyte counts were lower in novel flu patients, and chest CT images showed bilateral shadows and pure ground-glass opacities more frequently in the novel flu cases. There were no differences in treatment, number of days required for the fever to subside, or mortality between the groups. (author)

  12. Adaptation of Pandemic H1N1 Influenza Viruses in Mice▿

    Science.gov (United States)

    Ilyushina, Natalia A.; Khalenkov, Alexey M.; Seiler, Jon P.; Forrest, Heather L.; Bovin, Nicolai V.; Marjuki, Henju; Barman, Subrata; Webster, Robert G.; Webby, Richard J.

    2010-01-01

    The molecular mechanism by which pandemic 2009 influenza A viruses were able to sufficiently adapt to humans is largely unknown. Subsequent human infections with novel H1N1 influenza viruses prompted an investigation of the molecular determinants of the host range and pathogenicity of pandemic influenza viruses in mammals. To address this problem, we assessed the genetic basis for increased virulence of A/CA/04/09 (H1N1) and A/TN/1-560/09 (H1N1) isolates, which are not lethal for mice, in a new mammalian host by promoting their mouse adaptation. The resulting mouse lung-adapted variants showed significantly enhanced growth characteristics in eggs, extended extrapulmonary tissue tropism, and pathogenicity in mice. All mouse-adapted viruses except A/TN/1-560/09-MA2 grew faster and to higher titers in cells than the original strains. We found that 10 amino acid changes in the ribonucleoprotein (RNP) complex (PB2 E158G/A, PA L295P, NP D101G, and NP H289Y) and hemagglutinin (HA) glycoprotein (K119N, G155E, S183P, R221K, and D222G) controlled enhanced mouse virulence of pandemic isolates. HA mutations acquired during adaptation affected viral receptor specificity by enhancing binding to α2,3 together with decreasing binding to α2,6 sialyl receptors. PB2 E158G/A and PA L295P amino acid substitutions were responsible for the significant enhancement of transcription and replication activity of the mouse-adapted H1N1 variants. Taken together, our findings suggest that changes optimizing receptor specificity and interaction of viral polymerase components with host cellular factors are the major mechanisms that contribute to the optimal competitive advantage of pandemic influenza viruses in mice. These modulators of virulence, therefore, may have been the driving components of early evolution, which paved the way for novel 2009 viruses in mammals. PMID:20592084

  13. Characterizing the epidemiology of the 2009 influenza A/H1N1 pandemic in Mexico.

    Directory of Open Access Journals (Sweden)

    Gerardo Chowell

    2011-05-01

    Full Text Available BACKGROUND: Mexico's local and national authorities initiated an intense public health response during the early stages of the 2009 A/H1N1 pandemic. In this study we analyzed the epidemiological patterns of the pandemic during April-December 2009 in Mexico and evaluated the impact of nonmedical interventions, school cycles, and demographic factors on influenza transmission. METHODS AND FINDINGS: We used influenza surveillance data compiled by the Mexican Institute for Social Security, representing 40% of the population, to study patterns in influenza-like illness (ILIs hospitalizations, deaths, and case-fatality rate by pandemic wave and geographical region. We also estimated the reproduction number (R on the basis of the growth rate of daily cases, and used a transmission model to evaluate the effectiveness of mitigation strategies initiated during the spring pandemic wave. A total of 117,626 ILI cases were identified during April-December 2009, of which 30.6% were tested for influenza, and 23.3% were positive for the influenza A/H1N1 pandemic virus. A three-wave pandemic profile was identified, with an initial wave in April-May (Mexico City area, a second wave in June-July (southeastern states, and a geographically widespread third wave in August-December. The median age of laboratory confirmed ILI cases was ∼ 18 years overall and increased to ∼ 31 years during autumn (p<0.0001. The case-fatality ratio among ILI cases was 1.2% overall, and highest (5.5% among people over 60 years. The regional R estimates were 1.8-2.1, 1.6-1.9, and 1.2-1.3 for the spring, summer, and fall waves, respectively. We estimate that the 18-day period of mandatory school closures and other social distancing measures implemented in the greater Mexico City area was associated with a 29%-37% reduction in influenza transmission in spring 2009. In addition, an increase in R was observed in late May and early June in the southeast states, after mandatory school

  14. Genetic characterization of the influenza A pandemic (H1N1 2009 virus isolates from India.

    Directory of Open Access Journals (Sweden)

    Varsha A Potdar

    Full Text Available BACKGROUND: The Influenza A pandemic H1N1 2009 (H1N1pdm virus appeared in India in May 2009 and thereafter outbreaks with considerable morbidity and mortality have been reported from many parts of the country. Continuous monitoring of the genetic makeup of the virus is essential to understand its evolution within the country in relation to global diversification and to track the mutations that may affect the behavior of the virus. METHODS: H1N1pdm viruses were isolated from both recovered and fatal cases representing major cities and sequenced. Phylogenetic analyses of six concatenated whole genomes and the hemagglutinin (HA gene of seven more isolates from May-September 2009 was performed with reference to 685 whole genomes of global isolates available as of November 24, 2009. Molecular characterization of all the 8 segments was carried out for known pathogenic markers. RESULTS: The first isolate of May 2009 belonged to clade 5. Although clade 7 was the dominant H1N1pdm lineage in India, both clades 6 and 7 were found to be co-circulating. The neuraminidase of all the Indian isolates possessed H275, the marker for sensitivity to the neuraminidase inhibitor Oseltamivir. Some of the mutations in HA are at or in the vicinity of antigenic sites and may therefore be of possible antigenic significance. Among these a D222G mutation in the HA receptor binding domain was found in two of the eight Indian isolates obtained from fatal cases. CONCLUSIONS: The majority of the 13 Indian isolates grouped in the globally most widely circulating H1N1pdm clade 7. Further, correlations of the mutations specific to clade 7 Indian isolates to viral fitness and adaptability in the country remains to be understood. The D222G mutation in HA from isolates of fatal cases needs to be studied for pathogenicity.

  15. Serosurveillance for pandemic influenza A (H1N1 2009 virus infection in domestic elephants, Thailand.

    Directory of Open Access Journals (Sweden)

    Weena Paungpin

    Full Text Available The present study conducted serosurveillance for the presence of antibody to pandemic influenza A (H1N1 2009 virus (H1N1pdm virus in archival serum samples collected between 2009 and 2013 from 317 domestic elephants living in 19 provinces situated in various parts of Thailand. To obtain the most accurate data, hemagglutination-inhibition (HI assay was employed as the screening test; and sera with HI antibody titers ≥20 were further confirmed by other methods, including cytopathic effect/hemagglutination based-microneutralization (microNT and Western blot (WB assays using H1N1pdm matrix 1 (M1 or hemagglutinin (HA recombinant protein as the test antigen. Conclusively, the appropriate assays using HI in conjunction with WB assays for HA antibody revealed an overall seropositive rate of 8.5% (27 of 317. The prevalence of antibody to H1N1pdm virus was 2% (4/172 in 2009, 32% (17/53 in 2010, 9% (2/22 in 2011, 12% (1/8 in 2012, and 5% (3/62 in 2013. Notably, these positive serum samples were collected from elephants living in 7 tourist provinces of Thailand. The highest seropositive rate was obtained from elephants in Phuket, a popular tourist beach city. Young elephants had higher seropositive rate than older elephants. The source of H1N1pdm viral infection in these elephants was not explored, but most likely came from close contact with the infected mahouts or from the infected tourists who engaged in activities such as elephant riding and feeding. Nevertheless, it could not be excluded that elephant-to-elephant transmission did occur.

  16. Clinical characteristics and outcomes among pediatric patients hospitalized with pandemic influenza A/H1N1 2009 infection

    Directory of Open Access Journals (Sweden)

    Eun Lee

    2011-08-01

    Full Text Available Purpose : The purpose of this article is to describe the clinical and epidemiologic features and outcomes among children hospitalized with pandemic influenza A/H1N1 2009 infection. Methods : We retrospectively reviewed the charts of hospitalized pediatric patients (&lt;18 years diagnosed with pandemic influenza A/H1N1 2009 infection by reverse-transcriptase polymerase chain reaction at a tertiary hospital in Seoul, Korea, between September 2009 and February 2010. Results : A total of 72 children were hospitalized with pandemic influenza A/H1N1 2009 infection (median age, 6.0 years; range, 2 months to 18 years. A total of 40% had at least 1 underlying medical condition, including asthma (17%, malignancies (19%, and heart diseases (17%. Of the 72 patients, 54 (76% children admitted with H1N1 infection showed radiographic alterations compatible with pneumonia. There was no significant difference in pre-existing conditions between pandemic influenza A/H1N1 infected patients with or without pneumonia. Children with pandemic influenza A/ H1N1 pneumonia were more likely to have a lower lymphocyte ratio (P=0.02, higher platelet count (P=0.02, and higher level of serum glucose (P=0.003, and more commonly presented with dyspnea than did those without pneumonia (P=0.04. Conclusion : No significant differences in age, sex, or presence of preexisting conditions were found between children hospitalized with pandemic influenza A/H1N1 H1N1 influenza infection with pneumonia and those without pneumonia. Higher leukocyte count, higher glucose level, and a lower lymphocyte ratio were associated with the development of pandemic A/H1N1 2009 influenza pneumonia.

  17. The H1N1 influenza pandemic: need for solutions to ethical problems.

    Science.gov (United States)

    Bhatia, Prateek

    2013-01-01

    The rapid spread of the novel influenza virus of H1N1 swine origin led to widespread fear, panic and unrest among the public and healthcare personnel. The pandemic not only tested the world's health preparedness, but also brought up new ethical issues which need to be addressed as soon as possible. This article highlights these issues and suggests ethical answers to the same. The main areas that require attention are the distribution of scarce resources, prioritisation of antiviral drugs and vaccines, obligations of healthcare workers, and adequate dissemination and proper communication of information related to the pandemic. It is of great importance to plan in advance how to confront these issues in an ethical manner. This is possible only if a comprehensive contingency plan is prepared with the involvement of and in consultation with all the stakeholders concerned.

  18. Severe pandemic 2009 H1N1 influenza disease due to pathogenic immune complexes

    Science.gov (United States)

    Monsalvo, Ana Clara; Batalle, Juan P.; Lopez, M. Florencia; Krause, Jens C.; Klemenc, Jennifer; Zea, Johanna; Maskin, Bernardo; Bugna, Jimena; Rubinstein, Carlos; Aguilar, Leandro; Dalurzo, Liliana; Libster, Romina; Savy, Vilma; Baumeister, Elsa; Aguilar, Liliana; Cabral, Graciela; Font, Julia; Solari, Liliana; Weller, Kevin P.; Johnson, Joyce; Echavarria, Marcela; Edwards, Kathryn M.; Chappell, James D.; Crowe, James E.; Williams, John V.; Melendi, Guillermina A.; Polack, Fernando P.

    2010-01-01

    Pandemic influenza viruses often cause severe disease in middle-aged adults without preexistent co-morbidities. The mechanism of illness associated with severe disease in this age group is not well understood1–10. Here, we demonstrate preexisting serum antibody that cross-reacts with, but does not protect against 2009 H1N1 influenza virus in middle-aged adults. Non-protective antibody is associated with immune complex(IC)-mediated disease after infection. High titers of serum antibody of low avidity for H1-2009 antigen, and low avidity pulmonary ICs against the same protein were detected in severely ill patients. Moreover, C4d deposition - a sensitive marker of complement activation mediated by ICs- was present in lung sections of fatal cases. Archived lung sections from adults with confirmed fatal influenza 1957 H2N2 infection revealed a similar mechanism of illness. These observations provide a novel biological mechanism for the unusual age distribution of severe cases during influenza pandemics. PMID:21131958

  19. Mortality attributable to pandemic influenza A (H1N1) 2009 in San Luis Potosí, Mexico

    Science.gov (United States)

    Comas‐García, Andreu; García‐Sepúlveda, Christian A.; Méndez‐de Lira, José J.; Aranda‐Romo, Saray; Hernández‐Salinas, Alba E.; Noyola, Daniel E.

    2010-01-01

    Please cite this paper as: Comas‐García et al. (2011) Mortality attributable to pandemic influenza A (H1N1) 2009 in San Luis Potosí, Mexico. Influenza and Other Respiratory Viruses 5(2), 76–82. Background  Acute respiratory infections are a leading cause of morbidity and mortality worldwide. Starting in 2009, pandemic influenza A(H1N1) 2009 virus has become one of the leading respiratory pathogens worldwide. However, the overall impact of this virus as a cause of mortality has not been clearly defined. Objectives  To determine the impact of pandemic influenza A(H1N1) 2009 on mortality in a Mexican population. Methods  We assessed the impact of pandemic influenza virus on mortality during the first and second outbreaks in San Luis Potosí, Mexico, and compared it to mortality associated with seasonal influenza and respiratory syncytial virus (RSV) during the previous winter seasons. Results  We estimated that, on average, 8·1% of all deaths that occurred during the 2003–2009 seasons were attributable to influenza and RSV. During the first pandemic influenza A(H1N1) 2009 outbreak, there was an increase in mortality in persons 5–59 years of age, but not during the second outbreak (Fall of 2009). Overall, pandemic influenza A (H1N1) 2009 outbreaks had similar effects on mortality to those associated with seasonal influenza virus epidemics. Conclusions  The impact of influenza A(H1N1) 2009 virus on mortality during the first year of the pandemic was similar to that observed for seasonal influenza. The establishment of real‐time surveillance systems capable of integrating virological, morbidity, and mortality data may result in the timely identification of outbreaks so as to allow for the institution of appropriate control measures to reduce the impact of emerging pathogens on the population. PMID:21306570

  20. Willingness to accept H1N1 pandemic influenza vaccine: A cross-sectional study of Hong Kong community nurses

    Directory of Open Access Journals (Sweden)

    Wong Carmen

    2010-10-01

    Full Text Available Abstract Background The 2009 pandemic of influenza A (H1N1 infection has alerted many governments to make preparedness plan to control the spread of influenza A (H1N1 infection. Vaccination for influenza is one of the most important primary preventative measures to reduce the disease burden. Our study aims to assess the willingness of nurses who work for the community nursing service (CNS in Hong Kong on their acceptance of influenza A (H1N1 influenza vaccination. Methods 401 questionnaires were posted from June 24, 2009 to June 30, 2009 to community nurses with 67% response rate. Results of the 267 respondents on their willingness to accept influenza A (H1N1 vaccine were analyzed. Results Twenty-seven percent of respondents were willing to accept influenza vaccination if vaccines were available. Having been vaccinated for seasonable influenza in the previous 12 months were significantly independently associated with their willingness to accept influenza A (H1N1 vaccination (OR = 4.03; 95% CI: 2.03-7.98. Conclusions Similar to previous findings conducted in hospital healthcare workers and nurses, we confirmed that the willingness of community nurses to accept influenza A (H1N1 vaccination is low. Future studies that evaluate interventions to address nurses' specific concerns or interventions that aim to raise the awareness among nurses on the importance of influenza A (H1N1 vaccination to protect vulnerable patient populations is needed.

  1. [Technical report on the 2009 influenza A (H1N1) pandemic].

    Science.gov (United States)

    2010-01-01

    Since its appearance in April 2009, the influenza A (H1N1) pandemic has been a subject of continued attention by national and international health authorities, as well as in the communication media. It has been six months since the first cases were published and the winter season has just ended in the southern hemisphere. Therefore, we now have quite extensive knowledge on the behaviour of the disease, its severity and the way it manifests itself in the child/adolescent population. The Spanish Paediatric Association commissioned its Evidence Based Medicine Working Group to prepare a technical report on the influenza pandemic. This report has been prepared following the highly structured working methodology proposed by the so-called Evidence Based Medicine (EBM). This methodology requires formulating clinical questions, carrying out a systematic review of the literature looking for research works that could answer them, the critical reading of these, evaluating their methodology quality and clinical importance and finally, establishing recommendations based on those studies considered valid and important as well as on good clinical judgement. The present report approaches all aspects of the influenza pandemic considered to be of interest: extent of the disease, clinical and laboratory diagnosis, physical prevention measures, vaccination and pharmacological treatment. The target population of the report are children and adolescents. Many of the considerations made may also be applied to other age groups. The primary objective of this report is to establish a group of recommendations which may serve as a generic framework for the prevention, diagnosis and treatment of the pandemic influenza in children and adolescents. The final targets of the report are paediatricians and also general/family doctors and nurses who look after children and adolescents. Copyright (c) 2009 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  2. Genetic diversity of the 2009 pandemic influenza A(H1N1 viruses in Finland.

    Directory of Open Access Journals (Sweden)

    Niina Ikonen

    Full Text Available BACKGROUND: In Finland, the first infections caused by the 2009 pandemic influenza A(H1N1 virus were identified on May 10. During the next three months almost all infections were found from patients who had recently traveled abroad. In September 2009 the pandemic virus started to spread in the general population, leading to localized outbreaks and peak epidemic activity was reached during weeks 43-48. METHODS/RESULTS: The nucleotide sequences of the hemagglutinin (HA and neuraminidase (NA genes from viruses collected from 138 patients were determined. The analyzed viruses represented mild and severe infections and different geographic regions and time periods. Based on HA and NA gene sequences, the Finnish pandemic viruses clustered in four groups. Finnish epidemic viruses and A/California/07/2009 vaccine virus strain varied from 2-8 and 0-5 amino acids in HA and NA molecules, respectively, giving a respective maximal evolution speed of 1.4% and 1.1%. Most amino acid changes in HA and NA molecules accumulated on the surface of the molecule and were partly located in antigenic sites. Three severe infections were detected with a mutation at HA residue 222, in two viruses with a change D222G, and in one virus D222Y. Also viruses with change D222E were identified. All Finnish pandemic viruses were sensitive to oseltamivir having the amino acid histidine at residue 275 of the neuraminidase molecule. CONCLUSIONS: The Finnish pandemic viruses were quite closely related to A/California/07/2009 vaccine virus. Neither in the HA nor in the NA were changes identified that may lead to the selection of a virus with increased epidemic potential or exceptionally high virulence. Continued laboratory-based surveillance of the 2009 pandemic influenza A(H1N1 is important in order to rapidly identify drug resistant viruses and/or virus variants with potential ability to cause severe forms of infection and an ability to circumvent vaccine-induced immunity.

  3. Student behavior during a school closure caused by pandemic influenza A/H1N1.

    Science.gov (United States)

    Miller, Joel C; Danon, Leon; O'Hagan, Justin J; Goldstein, Edward; Lajous, Martin; Lipsitch, Marc

    2010-05-05

    Many schools were temporarily closed in response to outbreaks of the recently emerged pandemic influenza A/H1N1 virus. The effectiveness of closing schools to reduce transmission depends largely on student/family behavior during the closure. We sought to improve our understanding of these behaviors. To characterize this behavior, we surveyed students in grades 9-12 and parents of students in grades 5-8 about student activities during a week long closure of a school during the first months after the disease emerged. We found significant interaction with the community and other students-though less interaction with other students than during school-with the level of interaction increasing with grade. Our results are useful for the future design of social distancing policies and to improving the ability of modeling studies to accurately predict their impact.

  4. Student behavior during a school closure caused by pandemic influenza A/H1N1.

    Directory of Open Access Journals (Sweden)

    Joel C Miller

    Full Text Available BACKGROUND: Many schools were temporarily closed in response to outbreaks of the recently emerged pandemic influenza A/H1N1 virus. The effectiveness of closing schools to reduce transmission depends largely on student/family behavior during the closure. We sought to improve our understanding of these behaviors. METHODOLOGY/PRINCIPAL FINDINGS: To characterize this behavior, we surveyed students in grades 9-12 and parents of students in grades 5-8 about student activities during a week long closure of a school during the first months after the disease emerged. We found significant interaction with the community and other students-though less interaction with other students than during school-with the level of interaction increasing with grade. CONCLUSIONS: Our results are useful for the future design of social distancing policies and to improving the ability of modeling studies to accurately predict their impact.

  5. Pandemic H1N1 2009 virus in Norwegian pigs naïve to influenza A viruses

    DEFF Research Database (Denmark)

    Germundsson, A.; Gjerset, B.; Hjulsager, Charlotte Kristiane

    In March-April 2009, a novel pandemic influenza A (H1N1) virus (pH1N1-09v) emerged in the human population. The first case of pH1N1v infection in pigs was reported from Canada in May 2009. In Norway, pH1N1v infection was recorded in a swine herd on the 10th of October of 2009. Here, we report...... isolated from a confirmed human case at the farm. The majority of the positive herds had a history of contact with humans that were diagnosed with pandemic influenza or with ILI. This suggests that infected humans are the most likely source for introduction of pH1N1-09v to the Norwegian pig herds...

  6. An Analysis of 332 Fatalities Infected with Pandemic 2009 Influenza A (H1N1) in Argentina

    Science.gov (United States)

    Balanzat, Ana M.; Hertlein, Christian; Apezteguia, Carlos; Bonvehi, Pablo; Cámera, Luis; Gentile, Angela; Rizzo, Oscar; Gómez-Carrillo, Manuel; Coronado, Fatima; Azziz-Baumgartner, Eduardo; Chávez, Pollyanna R.; Widdowson, Marc-Alain

    2012-01-01

    Background The apparent high number of deaths in Argentina during the 2009 pandemic led to concern that the influenza A H1N1pdm disease was different there. We report the characteristics and risk factors for influenza A H1N1pdm fatalities. Methods We identified laboratory-confirmed influenza A H1N1pdm fatalities occurring during June-July 2009. Physicians abstracted data on age, sex, time of onset of illness, medical history, clinical presentation at admission, laboratory, treatment, and outcomes using standardize questionnaires. We explored the characteristics of fatalities according to their age and risk group. Results Of 332 influenza A H1N1pdm fatalities, 226 (68%) were among persons aged Argentina, though timeliness of antiviral treatment improved during the pandemic. PMID:22506006

  7. Household transmission of influenza A(H1N1pdm09 in the pandemic and post-pandemic seasons.

    Directory of Open Access Journals (Sweden)

    Itziar Casado

    Full Text Available The transmission of influenza viruses occurs person to person and is facilitated by contacts within enclosed environments such as households. The aim of this study was to evaluate secondary attack rates and factors associated with household transmission of laboratory-confirmed influenza A(H1N1pdm09 in the pandemic and post-pandemic seasons.During the 2009-2010 and 2010-2011 influenza seasons, 76 sentinel physicians in Navarra, Spain, took nasopharyngeal and pharyngeal swabs from patients diagnosed with influenza-like illness. A trained nurse telephoned households of those patients who were laboratory-confirmed for influenza A(H1N1pdm09 to ask about the symptoms, risk factors and vaccination status of each household member.In the 405 households with a patient laboratory-confirmed for influenza A(H1N1pdm09, 977 susceptible contacts were identified; 16% of them (95% CI 14-19% presented influenza-like illness and were considered as secondary cases. The secondary attack rate was 14% in 2009-2010 and 19% in the 2010-2011 season (p=0.049, an increase that mainly affected persons with major chronic conditions. In the multivariate logistic regression analysis, the risk of being a secondary case was higher in the 2010-2011 season than in the 2009-2010 season (adjusted odds ratio: 1.72; 95% CI 1.17-2.54, and in children under 5 years, with a decreasing risk in older contacts. Influenza vaccination was associated with lesser incidence of influenza-like illness near to statistical significance (adjusted odds ratio: 0.29; 95% CI 0.08-1.03.The secondary attack rate in households was higher in the second season than in the first pandemic season. Children had a greater risk of infection. Preventive measures should be maintained in the second pandemic season, especially in high-risk persons.

  8. Assessing Google flu trends performance in the United States during the 2009 influenza virus A (H1N1 pandemic.

    Directory of Open Access Journals (Sweden)

    Samantha Cook

    Full Text Available 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 pH1

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

    Science.gov (United States)

    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

  10. Novel pandemic influenza A(H1N1 viruses are potently inhibited by DAS181, a sialidase fusion protein.

    Directory of Open Access Journals (Sweden)

    Gallen B Triana-Baltzer

    2009-11-01

    Full Text Available The recent emergence of a novel pandemic influenza A(H1N1 strain in humans exemplifies the rapid and unpredictable nature of influenza virus evolution and the need for effective therapeutics and vaccines to control such outbreaks. However, resistance to antivirals can be a formidable problem as evidenced by the currently widespread oseltamivir- and adamantane-resistant seasonal influenza A viruses (IFV. Additional antiviral approaches with novel mechanisms of action are needed to combat novel and resistant influenza strains. DAS181 (Fludase is a sialidase fusion protein in early clinical development with in vitro and in vivo preclinical activity against a variety of seasonal influenza strains and highly pathogenic avian influenza strains (A/H5N1. Here, we use in vitro, ex vivo, and in vivo models to evaluate the activity of DAS181 against several pandemic influenza A(H1N1 viruses.The activity of DAS181 against several pandemic influenza A(H1N1 virus isolates was examined in MDCK cells, differentiated primary human respiratory tract culture, ex-vivo human bronchi tissue and mice. DAS181 efficiently inhibited viral replication in each of these models and against all tested pandemic influenza A(H1N1 strains. DAS181 treatment also protected mice from pandemic influenza A(H1N1-induced pathogenesis. Furthermore, DAS181 antiviral activity against pandemic influenza A(H1N1 strains was comparable to that observed against seasonal influenza virus including the H274Y oseltamivir-resistant influenza virus.The sialidase fusion protein DAS181 exhibits potent inhibitory activity against pandemic influenza A(H1N1 viruses. As inhibition was also observed with oseltamivir-resistant IFV (H274Y, DAS181 may be active against the antigenically novel pandemic influenza A(H1N1 virus should it acquire the H274Y mutation. Based on these and previous results demonstrating DAS181 broad-spectrum anti-IFV activity, DAS181 represents a potential therapeutic agent for

  11. Spreading patterns of the influenza A (H1N1 pandemic.

    Directory of Open Access Journals (Sweden)

    Sergio de Picoli Junior

    Full Text Available We investigate the dynamics of the 2009 influenza A (H1N1/S-OIV pandemic by analyzing data obtained from World Health Organization containing the total number of laboratory-confirmed cases of infections--by country--in a period of 69 days, from 26 April to 3 July, 2009. Specifically, we find evidence of exponential growth in the total number of confirmed cases and linear growth in the number of countries with confirmed cases. We also find that, i at early stages, the cumulative distribution of cases among countries exhibits linear behavior on log-log scale, being well approximated by a power law decay; ii for larger times, the cumulative distribution presents a systematic curvature on log-log scale, indicating a gradual change to lognormal behavior. Finally, we compare these empirical findings with the predictions of a simple stochastic model. Our results could help to select more realistic models of the dynamics of influenza-type pandemics.

  12. Streptococcus pneumoniae Coinfection Is Correlated with the Severity of H1N1 Pandemic Influenza

    Science.gov (United States)

    Cisterna, Daniel; Savji, Nazir; Bussetti, Ana Valeria; Kapoor, Vishal; Hui, Jeffrey; Tokarz, Rafal; Briese, Thomas; Baumeister, Elsa; Lipkin, W. Ian

    2009-01-01

    Background Initial reports in May 2009 of the novel influenza strain H1N1pdm estimated a case fatality rate (CFR) of 0.6%, similar to that of seasonal influenza. In July 2009, however, Argentina reported 3056 cases with 137 deaths, representing a CFR of 4.5%. Potential explanations for increased CFR included virus reassortment or genetic drift, or infection of a more vulnerable population. Virus genomic sequencing of 26 Argentinian samples representing both severe and mild disease indicated no evidence of reassortment, mutations associated with resistance to antiviral drugs, or genetic drift that might contribute to virulence. Furthermore, no evidence was found for increased frequency of risk factors for H1N1pdm disease. Methods/Principal Findings We examined nasopharyngeal swab samples (NPS) from 199 cases of H1N1pdm infection from Argentina with MassTag PCR, testing for 33 additional microbial agents. The study population consisted of 199 H1N1pdm-infected subjects sampled between 23 June and 4 July 2009. Thirty-nine had severe disease defined as death (n = 20) or hospitalization (n = 19); 160 had mild disease. At least one additional agent of potential pathogenic importance was identified in 152 samples (76%), including Streptococcus pneumoniae (n = 62); Haemophilus influenzae (n = 104); human respiratory syncytial virus A (n = 11) and B (n = 1); human rhinovirus A (n = 1) and B (n = 4); human coronaviruses 229E (n = 1) and OC43 (n = 2); Klebsiella pneumoniae (n = 2); Acinetobacter baumannii (n = 2); Serratia marcescens (n = 1); and Staphylococcus aureus (n = 35) and methicillin-resistant S. aureus (MRSA, n = 6). The presence of S. pneumoniae was strongly correlated with severe disease. S. pneumoniae was present in 56.4% of severe cases versus 25% of mild cases; more than one-third of H1N1pdm NPS with S. pneumoniae were from subjects with severe disease (22 of 62 S. pneumoniae-positive NPS, p = 0

  13. Pandemic influenza A H1N1 2009 infection versus vaccination: a cohort study comparing immune responses in pregnancy.

    Directory of Open Access Journals (Sweden)

    Barbra M Fisher

    Full Text Available BACKGROUND: With the emergence of H1N1 pandemic (pH1N1 influenza, the CDC recommended that pregnant women be one of five initial target groups to receive the 2009 monovalent H1N1 vaccine, regardless of prior infection with this influenza strain. We sought to compare the immune response of pregnant women to H1N1 infection versus vaccination and to determine the extent of passive immunity conferred to the newborn. METHODS/FINDINGS: During the 2009-2010 influenza season, we enrolled a cohort of women who either had confirmed pH1N1 infection during pregnancy, did not have pH1N1 during pregnancy but were vaccinated against pH1N1, or did not have illness or vaccination. Maternal and umbilical cord venous blood samples were collected at delivery. Hemagglutination inhibition assays (HAI for pH1N1 were performed. Data were analyzed using linear regression analyses. HAIs were performed for matched maternal/cord blood pairs for 16 women with confirmed pH1N1 infection, 14 women vaccinated against pH1N1, and 10 women without infection or vaccination. We found that pH1N1 vaccination and wild-type infection during pregnancy did not differ with respect to (1 HAI titers at delivery, (2 HAI antibody decay slopes over time, and (3 HAI titers in the cord blood. CONCLUSIONS: Vaccination against pH1N1 confers a similar HAI antibody response as compared to pH1N1 infection during pregnancy, both in quantity and quality. Illness or vaccination during pregnancy confers passive immunity to the newborn.

  14. Immune protection induced on day 10 following administration of the 2009 A/H1N1 pandemic influenza vaccine.

    Directory of Open Access Journals (Sweden)

    Yizhuo Sun

    Full Text Available BACKGROUND: The 2009 swine-origin influenza virus (S-OIV H1N1 pandemic has caused more than 18,000 deaths worldwide. Vaccines against the 2009 A/H1N1 influenza virus are useful for preventing infection and controlling the pandemic. The kinetics of the immune response following vaccination with the 2009 A/H1N1 influenza vaccine need further investigation. METHODOLOGY/PRINCIPAL FINDINGS: 58 volunteers were vaccinated with a 2009 A/H1N1 pandemic influenza monovalent split-virus vaccine (15 µg, single-dose. The sera were collected before Day 0 (pre-vaccination and on Days 3, 5, 10, 14, 21, 30, 45 and 60 post vaccination. Specific antibody responses induced by the vaccination were analyzed using hemagglutination inhibition (HI assay and enzyme-linked immunosorbent assay (ELISA. After administration of the 2009 A/H1N1 influenza vaccine, specific and protective antibody response with a major subtype of IgG was sufficiently developed as early as Day 10 (seroprotection rate: 93%. This specific antibody response could maintain for at least 60 days without significant reduction. Antibody response induced by the 2009 A/H1N1 influenza vaccine could not render protection against seasonal H1N1 influenza (seroconversion rate: 3% on Day 21. However, volunteers with higher pre-existing seasonal influenza antibody levels (pre-vaccination HI titer ≥1∶40, Group 1 more easily developed a strong antibody protection effect against the 2009 A/H1N1 influenza vaccine as compared with those showing lower pre-existing seasonal influenza antibody levels (pre-vaccination HI titer <1∶40, Group 2. The titer of the specific antibody against the 2009 A/H1N1 influenza was much higher in Group 1 (geometric mean titer: 146 on Day 21 than that in Group 2 (geometric mean titer: 70 on Day 21. CONCLUSIONS/SIGNIFICANCE: Recipients could gain sufficient protection as early as 10 days after vaccine administration. The protection could last at least 60 days. Individuals with a

  15. Determination of preventive behaviors for pandemic influenza A/H1N1 based on protection motivation theory among female high school students in Isfahan, Iran

    OpenAIRE

    Sharifirad, Gholamreza; Yarmohammadi, Parastoo; Sharifabad, Mohammad Ali Morowati; Rahaei, Zohreh

    2014-01-01

    Introduction: Influenza A/H1N1 pandemic has recently threatened the health of world's population more than ever. Non-pharmaceutical measures are important to prevent the spread of influenza A/H1N1 and to prevent a pandemic. Effective influenza pandemic management requires understanding of the factors influencing preventive behavioral. This study reports on predictors of students’ preventive behaviors for pandemic influenza A/H1N1 using variables based on the protection motivation theory (PMT)...

  16. Functional Evolution of Influenza Virus NS1 Protein in Currently Circulating Human 2009 Pandemic H1N1 Viruses.

    Science.gov (United States)

    Clark, Amelia M; Nogales, Aitor; Martinez-Sobrido, Luis; Topham, David J; DeDiego, Marta L

    2017-09-01

    In 2009, a novel H1N1 influenza virus emerged in humans, causing a global pandemic. It was previously shown that the NS1 protein from this human 2009 pandemic H1N1 (pH1N1) virus was an effective interferon (IFN) antagonist but could not inhibit general host gene expression, unlike other NS1 proteins from seasonal human H1N1 and H3N2 viruses. Here we show that the NS1 protein from currently circulating pH1N1 viruses has evolved to encode 6 amino acid changes (E55K, L90I, I123V, E125D, K131E, and N205S) with respect to the original protein. Notably, these 6 residue changes restore the ability of pH1N1 NS1 to inhibit general host gene expression, mainly by their ability to restore binding to the cellular factor CPSF30. This is the first report describing the ability of the pH1N1 NS1 protein to naturally acquire mutations that restore this function. Importantly, a recombinant pH1N1 virus containing these 6 amino acid changes in the NS1 protein (pH1N1/NSs-6mut) inhibited host IFN and proinflammatory responses to a greater extent than that with the parental virus (pH1N1/NS1-wt), yet virus titers were not significantly increased in cell cultures or in mouse lungs, and the disease was partially attenuated. The pH1N1/NSs-6mut virus grew similarly to pH1N1/NSs-wt in mouse lungs, but infection with pH1N1/NSs-6mut induced lower levels of proinflammatory cytokines, likely due to a general inhibition of gene expression mediated by the mutated NS1 protein. This lower level of inflammation induced by the pH1N1/NSs-6mut virus likely accounts for the attenuated disease phenotype and may represent a host-virus adaptation affecting influenza virus pathogenesis. IMPORTANCE Seasonal influenza A viruses (IAVs) are among the most common causes of respiratory infections in humans. In addition, occasional pandemics are caused when IAVs circulating in other species emerge in the human population. In 2009, a swine-origin H1N1 IAV (pH1N1) was transmitted to humans, infecting people then and up

  17. The Influenza A(H1N1)v Pandemic : An Exploratory System Dynamics Approach

    NARCIS (Netherlands)

    Pruyt, E.; Hamarat, C.

    2010-01-01

    This paper presents a small exploratory System Dynamics model related to the dynamics of the 2009 flu pandemic, also known as the Mexican flu, swine flu, or A(H1N1)v. The model was developed in May 2009 in order to quickly foster understanding about the possible dynamics of this new flu variant and

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

    Science.gov (United States)

    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...

  19. Pandemic vaccination strategies and influenza severe outcomes during the influenza A(H1N1)pdm09 pandemic and the post-pandemic influenza season

    DEFF Research Database (Denmark)

    Gil Cuesta, Julita; Aavitsland, Preben; Englund, Hélène

    2016-01-01

    During the 2009/10 influenza A(H1N1)pdm09 pandemic, the five Nordic countries adopted different approaches to pandemic vaccination. We compared pandemic vaccination strategies and severe influenza outcomes, in seasons 2009/10 and 2010/11 in these countries with similar influenza surveillance...... systems. We calculated the cumulative pandemic vaccination coverage in 2009/10 and cumulative incidence rates of laboratory confirmed A(H1N1)pdm09 infections, intensive care unit (ICU) admissions and deaths in 2009/10 and 2010/11. We estimated incidence risk ratios (IRR) in a Poisson regression model...... with the other countries. In 2010/11 Denmark had a significantly higher cumulative incidence of A(H1N1)pdm09 ICU admissions (IRR: 2.4; 95% confidence interval (CI): 1.9-3.0) and deaths (IRR: 8.3; 95% CI: 5.1-13.5). Compared with Denmark, the other countries had higher pandemic vaccination coverage...

  20. School illness absenteeism during 2009 influenza A (H1N1) pandemic--South Dakota, 2009-2010.

    Science.gov (United States)

    Kightlinger, Lon; Horan, Vickie

    2013-05-01

    Schools are important amplification settings of influenza virus transmission. We demonstrated correlation of school absenteeism (due to any illness) with other influenza A (H1N1) activity surveillance data during the 2009 pandemic. We collected nonspecific illness student absenteeism data from August 17, 2009 through April 3, 2010 from 187 voluntarily participating South Dakota schools using weekly online surveys. Relative risks (RR) were calculated as the ratio of the probability of absenteeism during elevated weeks versus the probability of absenteeism during the baseline weeks (RR = 1.89). We used Pearson correlation to associate absenteeism with laboratory-confirmed influenza cases, influenza cases diagnosed by rapid tests, influenza-associated hospitalizations and deaths reported in South Dakota during the 2009 H1N1 pandemic period. School-absenteeism data correlated strongly with data from these other influenza surveillance sources.

  1. Humans and ferrets with prior H1N1 influenza virus infections do not exhibit evidence of original antigenic sin after infection or vaccination with the 2009 pandemic H1N1 influenza virus.

    Science.gov (United States)

    O'Donnell, Christopher D; Wright, Amber; Vogel, Leatrice; Boonnak, Kobporn; Treanor, John J; Subbarao, Kanta

    2014-05-01

    The hypothesis of original antigenic sin (OAS) states that the imprint established by an individual's first influenza virus infection governs the antibody response thereafter. Subsequent influenza virus infection results in an antibody response against the original infecting virus and an impaired immune response against the newer influenza virus. The purpose of our study was to seek evidence of OAS after infection or vaccination with the 2009 pandemic H1N1 (2009 pH1N1) virus in ferrets and humans previously infected with H1N1 viruses with various antigenic distances from the 2009 pH1N1 virus, including viruses from 1935 through 1999. In ferrets, seasonal H1N1 priming did not diminish the antibody response to infection or vaccination with the 2009 pH1N1 virus, nor did it diminish the T-cell response, indicating the absence of OAS in seasonal H1N1 virus-primed ferrets. Analysis of paired samples of human serum taken before and after vaccination with a monovalent inactivated 2009 pH1N1 vaccine showed a significantly greater-fold rise in the titer of antibody against the 2009 pH1N1 virus than against H1N1 viruses that circulated during the childhood of each subject. Thus, prior experience with H1N1 viruses did not result in an impairment of the antibody response against the 2009 pH1N1 vaccine. Our data from ferrets and humans suggest that prior exposure to H1N1 viruses did not impair the immune response against the 2009 pH1N1 virus.

  2. Protection from the 2009 H1N1 pandemic influenza by an antibody from combinatorial survivor-based libraries.

    Directory of Open Access Journals (Sweden)

    Arun K Kashyap

    2010-07-01

    Full Text Available Influenza viruses elude immune responses and antiviral chemotherapeutics through genetic drift and reassortment. As a result, the development of new strategies that attack a highly conserved viral function to prevent and/or treat influenza infection is being pursued. Such novel broadly acting antiviral therapies would be less susceptible to virus escape and provide a long lasting solution to the evolving virus challenge. Here we report the in vitro and in vivo activity of a human monoclonal antibody (A06 against two isolates of the 2009 H1N1 pandemic influenza virus. This antibody, which was obtained from a combinatorial library derived from a survivor of highly pathogenic H5N1 infection, neutralizes H5N1, seasonal H1N1 and 2009 "Swine" H1N1 pandemic influenza in vitro with similar potency and is capable of preventing and treating 2009 H1N1 influenza infection in murine models of disease. These results demonstrate broad activity of the A06 antibody and its utility as an anti-influenza treatment option, even against newly evolved influenza strains to which there is limited immunity in the general population.

  3. Epidemiological survey on pandemic influenza A (H1N1) virus infection in Kurdistan province, Islamic Republic of Iran, 2009.

    Science.gov (United States)

    Afrasiabian, S; Mohsenpour, B; Bagheri, K H; Barari, M; Ghaderi, E; Hashemi, R; Garibi, F

    2014-04-03

    This study evaluated the epidemiology of suspected cases of pandemic influenza A (H1N1) virus infection in 2009-2010 in Kurdistan province, a frontier province of the Islamic Republic of Iran. A questionnaire covering demographic characteristics, clinical presentation and outcome, and history of exposure and travel was completed by patients attending health centres and hospitals in the province. Nasal and throat swabs were analysed by RT-PCR. A total of 1059 suspected cases were assessed; H1N1 influenza A was confirmed in 157 (14.8%). The highest proportion of confirmed cases was 30.0%, among children aged Kurdistan.

  4. Long term immune responses to pandemic influenza A/H1N1 infection in solid organ transplant recipients.

    Directory of Open Access Journals (Sweden)

    Aliyah Baluch

    Full Text Available In solid organ transplant (SOT recipients it is unknown if natural infection with influenza confers protection from re-infection with the same strain during the next influenza season. The purpose of this study was to determine if infection with pandemic influenza A/H1N1 (pH1N1 resulted in a long-term immunologic response. Transplant recipients with microbiologically proven pH1N1 infection in 2009/2010 underwent humoral and cell-mediated immunity (CMI testing for pH1N1 just prior to the next influenza season. Concurrent testing for A/Brisbane/59/2007 was done to rule-out cross-reacting antibody. We enrolled 22 adult transplant patients after pH1N1 infection. Follow up testing was done at a median of 7.4 months (range 5.8-15.4 after infection. After excluding those with cross-reactive antibody, 7/19 (36.8% patients were seroprotected. Detectable pH1N1-specific CD4+ and CD8+ interferon-γ producing T-cells were found in 11/22 (50% and 8/22 (36.4% patients respectively. Humoral immunity had a significant correlation with a CD4 response. This is the first study in transplant patients to evaluate long-term humoral and cellular response after natural influenza infection. We show that a substantial proportion of SOT recipients with previous pH1N1 infection lack long-term humoral and cellular immune responses to pH1N1. These patients most likely are at risk for re-infection.

  5. Epidemiological characteristics of the influenza A(H1N1 2009 pandemic in the Western Pacific Region

    Directory of Open Access Journals (Sweden)

    Lisa McCallum

    2010-12-01

    Full Text Available The first laboratory-confirmed cases of infection with pandemic influenza A(H1N1 2009 in the Western Pacific Region were reported on 28 April 2009. By 11 June 2009, the day the pandemic was declared by the World Health Organization, nine Western Pacific Region countries and areas had reported laboratory-confirmed pandemic influenza A(H1N1 2009 cases. From April 2009 to July 2010, more than 250 000 cases and 1800 deaths from laboratory-confirmed pandemic influenza A(H1N1 2009 were reported from 34 countries and areas in the Region. By age group region-wide, 8.6%, 41.9%, 48.3%, and 1.2% of cases were in the < 5 years, 5–14 years, 15–64 years, and 65+ years age groups, respectively; the overall crude case fatality ratio in the Western Pacific Region was 0.5%. The pandemic demonstrated that region-wide disease reporting was possible. Countries and areas of the Western Pacific Region should take this opportunity to strengthen the systems established during the pandemic to develop routine disease reporting.

  6. Spatial and temporal characteristics of the 2009 A/H1N1 influenza pandemic in Peru.

    Science.gov (United States)

    Chowell, Gerardo; Viboud, Cécile; Munayco, Cesar V; Gómez, Jorge; Simonsen, Lone; Miller, Mark A; Tamerius, James; Fiestas, Victor; Halsey, Eric S; Laguna-Torres, Victor A

    2011-01-01

    Highly refined surveillance data on the 2009 A/H1N1 influenza pandemic are crucial to quantify the spatial and temporal characteristics of the pandemic. There is little information about the spatial-temporal dynamics of pandemic influenza in South America. Here we provide a quantitative description of the age-specific morbidity pandemic patterns across administrative areas of Peru. We used daily cases of influenza-like-illness, tests for A/H1N1 influenza virus infections, and laboratory-confirmed A/H1N1 influenza cases reported to the epidemiological surveillance system of Peru's Ministry of Health from May 1 to December 31, 2009. We analyzed the geographic spread of the pandemic waves and their association with the winter school vacation period, demographic factors, and absolute humidity. We also estimated the reproduction number and quantified the association between the winter school vacation period and the age distribution of cases. The national pandemic curve revealed a bimodal winter pandemic wave, with the first peak limited to school age children in the Lima metropolitan area, and the second peak more geographically widespread. The reproduction number was estimated at 1.6-2.2 for the Lima metropolitan area and 1.3-1.5 in the rest of Peru. We found a significant association between the timing of the school vacation period and changes in the age distribution of cases, while earlier pandemic onset was correlated with large population size. By contrast there was no association between pandemic dynamics and absolute humidity. Our results indicate substantial spatial variation in pandemic patterns across Peru, with two pandemic waves of varying timing and impact by age and region. Moreover, the Peru data suggest a hierarchical transmission pattern of pandemic influenza A/H1N1 driven by large population centers. The higher reproduction number of the first pandemic wave could be explained by high contact rates among school-age children, the age group most affected

  7. Spatial and Temporal Characteristics of the 2009 A/H1N1 Influenza Pandemic in Peru

    Science.gov (United States)

    Chowell, Gerardo; Viboud, Cécile; Munayco, Cesar V.; Gómez, Jorge; Simonsen, Lone; Miller, Mark A.; Tamerius, James; Fiestas, Victor; Halsey, Eric S.; Laguna-Torres, Victor A.

    2011-01-01

    Background Highly refined surveillance data on the 2009 A/H1N1 influenza pandemic are crucial to quantify the spatial and temporal characteristics of the pandemic. There is little information about the spatial-temporal dynamics of pandemic influenza in South America. Here we provide a quantitative description of the age-specific morbidity pandemic patterns across administrative areas of Peru. Methods We used daily cases of influenza-like-illness, tests for A/H1N1 influenza virus infections, and laboratory-confirmed A/H1N1 influenza cases reported to the epidemiological surveillance system of Peru's Ministry of Health from May 1 to December 31, 2009. We analyzed the geographic spread of the pandemic waves and their association with the winter school vacation period, demographic factors, and absolute humidity. We also estimated the reproduction number and quantified the association between the winter school vacation period and the age distribution of cases. Results The national pandemic curve revealed a bimodal winter pandemic wave, with the first peak limited to school age children in the Lima metropolitan area, and the second peak more geographically widespread. The reproduction number was estimated at 1.6–2.2 for the Lima metropolitan area and 1.3–1.5 in the rest of Peru. We found a significant association between the timing of the school vacation period and changes in the age distribution of cases, while earlier pandemic onset was correlated with large population size. By contrast there was no association between pandemic dynamics and absolute humidity. Conclusions Our results indicate substantial spatial variation in pandemic patterns across Peru, with two pandemic waves of varying timing and impact by age and region. Moreover, the Peru data suggest a hierarchical transmission pattern of pandemic influenza A/H1N1 driven by large population centers. The higher reproduction number of the first pandemic wave could be explained by high contact rates among school

  8. An analysis of 332 fatalities infected with pandemic 2009 influenza A (H1N1 in Argentina.

    Directory of Open Access Journals (Sweden)

    Ana M Balanzat

    Full Text Available The apparent high number of deaths in Argentina during the 2009 pandemic led to concern that the influenza A H1N1pdm disease was different there. We report the characteristics and risk factors for influenza A H1N1pdm fatalities.We identified laboratory-confirmed influenza A H1N1pdm fatalities occurring during June-July 2009. Physicians abstracted data on age, sex, time of onset of illness, medical history, clinical presentation at admission, laboratory, treatment, and outcomes using standardize questionnaires. We explored the characteristics of fatalities according to their age and risk group.Of 332 influenza A H1N1pdm fatalities, 226 (68% were among persons aged <50 years. Acute respiratory failure was the leading cause of death. Of all cases, 249 (75% had at least one comorbidity as defined by Advisory Committee on Immunization Practices. Obesity was reported in 32% with data and chronic pulmonary disease in 28%. Among the 40 deaths in children aged <5 years, chronic pulmonary disease (42% and neonatal pathologies (35% were the most common co-morbidities. Twenty (6% fatalities were among pregnant or postpartum women of which only 47% had diagnosed co-morbidities. Only 13% of patients received antiviral treatment within 48 hours of symptom onset. None of children aged <5 years or the pregnant women received antivirals within 48 h of symptom onset. As the pandemic progressed, the time from symptom-onset to medical care and to antiviral treatment decreased significantly among case-patients who subsequently died (p<0.001.Persons with co-morbidities, pregnant and who received antivirals late were over-represented among influenza A H1N1pdm deaths in Argentina, though timeliness of antiviral treatment improved during the pandemic.

  9. A metagenomic analysis of pandemic influenza A (2009 H1N1 infection in patients from North America.

    Directory of Open Access Journals (Sweden)

    Alexander L Greninger

    2010-10-01

    Full Text Available Although metagenomics has been previously employed for pathogen discovery, its cost and complexity have prevented its use as a practical front-line diagnostic for unknown infectious diseases. Here we demonstrate the utility of two metagenomics-based strategies, a pan-viral microarray (Virochip and deep sequencing, for the identification and characterization of 2009 pandemic H1N1 influenza A virus. Using nasopharyngeal swabs collected during the earliest stages of the pandemic in Mexico, Canada, and the United States (n = 17, the Virochip was able to detect a novel virus most closely related to swine influenza viruses without a priori information. Deep sequencing yielded reads corresponding to 2009 H1N1 influenza in each sample (percentage of aligned sequences corresponding to 2009 H1N1 ranging from 0.0011% to 10.9%, with up to 97% coverage of the influenza genome in one sample. Detection of 2009 H1N1 by deep sequencing was possible even at titers near the limits of detection for specific RT-PCR, and the percentage of sequence reads was linearly correlated with virus titer. Deep sequencing also provided insights into the upper respiratory microbiota and host gene expression in response to 2009 H1N1 infection. An unbiased analysis combining sequence data from all 17 outbreak samples revealed that 90% of the 2009 H1N1 genome could be assembled de novo without the use of any reference sequence, including assembly of several near full-length genomic segments. These results indicate that a streamlined metagenomics detection strategy can potentially replace the multiple conventional diagnostic tests required to investigate an outbreak of a novel pathogen, and provide a blueprint for comprehensive diagnosis of unexplained acute illnesses or outbreaks in clinical and public health settings.

  10. The Association of H1N1 Pandemic Influenza with Congenital Anomaly Prevalence in Europe

    DEFF Research Database (Denmark)

    Luteijn, Johannes Michiel; Addor, Marie-Claude; Arriola, Larraitz

    2015-01-01

    BACKGROUND: In the context of the European Surveillance of Congenital Anomalies (EUROCAT) surveillance response to the 2009 influenza pandemic, we sought to establish whether there was a detectable increase of congenital anomaly prevalence among pregnancies exposed to influenza seasons in general......, and whether any increase was greater during the 2009 pandemic than during other seasons. METHODS: We performed an ecologic time series analysis based on 26,967 pregnancies with nonchromosomal congenital anomaly conceived from January 2007 to March 2011, reported by 15 EUROCAT registries. Analysis...... and tricuspid atresia and stenosis during pandemic influenza season 2009, but not during 2007-2011 influenza seasons. For congenital anomalies, where there was no prior hypothesis, the prevalence of tetralogy of Fallot was strongly reduced during influenza seasons. CONCLUSIONS: Our data do not suggest...

  11. Continued dominance of pandemic A(H1N1 2009 influenza in Victoria, Australia in 2010

    Directory of Open Access Journals (Sweden)

    James E. Fielding

    2011-08-01

    Full Text Available The 2010 Victorian influenza season was characterized by normal seasonal influenza activity and the dominance of the pandemic A(H1N1 2009 strain. General Practice Sentinel Surveillance rates peaked at 9.4 ILI cases per 1000 consultations in week 36 for metropolitan practices, and at 10.5 ILI cases per 1000 in the following week for rural practices. Of the 678 ILI cases, 23% were vaccinated, a significantly higher percentage than in previous years. A significantly higher percentage of ILI patients were swabbed in 2010 compared to 2003–2008, but similar to 2009, with a similar percentage being positive for influenza as in previous years. Vaccination rates increased with patient age. Melbourne Medical Deputising Service rates peaked in week 35 at 19.1 ILI cases per 1000 consultations. Of the 1914 cases of influenza notified to the Department of Health, Victoria, 1812 (95% were influenza A infections - 1001 (55% pandemic A(H1N1 2009, 4 (<1% A(H3N2 and 807 (45% not subtyped; 88 (5% were influenza B; and 14 (< 1% were influenza A and B co-infections. The World Health Organization Collaborating Centre for Reference and Research on Influenza tested 403 isolates of which 261 were positive for influenza, 250 of which were influenza A and 11 were influenza B. Ninety-two per cent of the influenza A viruses were pandemic A(H1N1 2009, and following antigenic analysis all of these were found to be similar to the current vaccine strain. Three viruses (0.9% were found to be oseltamivir resistant due to an H275Y mutation in the neuraminidase gene.

  12. Pandemic A/H1N1v influenza 2009 in hospitalized children: a multicenter Belgian survey

    Directory of Open Access Journals (Sweden)

    Blumental Sophie

    2011-11-01

    Full Text Available Abstract Background During the 2009 influenza A/H1N1v pandemic, children were identified as a specific "at risk" group. We conducted a multicentric study to describe pattern of influenza A/H1N1v infection among hospitalized children in Brussels, Belgium. Methods From July 1, 2009, to January 31, 2010, we collected epidemiological and clinical data of all proven (positive H1N1v PCR and probable (positive influenza A antigen or culture pediatric cases of influenza A/H1N1v infections, hospitalized in four tertiary centers. Results During the epidemic period, an excess of 18% of pediatric outpatients and emergency department visits was registered. 215 children were hospitalized with proven/probable influenza A/H1N1v infection. Median age was 31 months. 47% had ≥ 1 comorbid conditions. Febrile respiratory illness was the most common presentation. 36% presented with initial gastrointestinal symptoms and 10% with neurological manifestations. 34% had pneumonia. Only 24% of the patients received oseltamivir but 57% received antibiotics. 10% of children were admitted to PICU, seven of whom with ARDS. Case fatality-rate was 5/215 (2%, concerning only children suffering from chronic neurological disorders. Children over 2 years of age showed a higher propensity to be admitted to PICU (16% vs 1%, p = 0.002 and a higher mortality rate (4% vs 0%, p = 0.06. Infants less than 3 months old showed a milder course of infection, with few respiratory and neurological complications. Conclusion Although influenza A/H1N1v infections were generally self-limited, pediatric burden of disease was significant. Compared to other countries experiencing different health care systems, our Belgian cohort was younger and received less frequently antiviral therapy; disease course and mortality were however similar.

  13. The impact of the pandemic influenza A(H1N1) 2009 virus on seasonal influenza A viruses in the southern hemisphere, 2009.

    Science.gov (United States)

    Blyth, C C; Kelso, A; McPhie, K A; Ratnamohan, V M; Catton, M; Druce, J D; Smith, D W; Williams, S H; Huang, Q S; Lopez, L; Schoub, B D; Venter, M; Dwyer, D E

    2010-08-05

    Data collected over winter 2009 by five World Health Organisation National Influenza Centres in the southern hemisphere were used to examine the circulation of pandemic and seasonal influenza A strains during the first pandemic wave in the southern hemisphere.There is compelling evidence that the pandemic influenza A(H1N1) 2009 virus significantly displaced seasonal influenza A(H1N1) and, to a lesser extent, A(H3N2) viruses circulating in the southern hemisphere. Complete replacement of seasonal influenza A strains, however, was not observed during the first pandemic wave.

  14. Healthcare workers as parents: attitudes toward vaccinating their children against pandemic influenza A/H1N1

    Directory of Open Access Journals (Sweden)

    Torun Fuat

    2010-10-01

    Full Text Available Abstract Background Both the health care workers (HCWs and children are target groups for pandemic influenza vaccination. The coverage of the target populations is an important determinant for impact of mass vaccination. The objective of this study is to determine the attitudes of HCWs as parents, toward vaccinating their children with pandemic influenza A/H1N1 vaccine. Methods A cross-sectional questionnaire survey was conducted with health care workers (HCWs in a public hospital during December 2009 in Istanbul. All persons employed in the hospital with or without a health-care occupation are accepted as HCW. The HCWs who are parents of children 6 months to 18 years of age were included in the study. Pearson's chi-square test and logistic regression analysis was applied for the statistical analyses. Results A total of 389 HCWs who were parents of children aged 6 months-18 years participated study. Among all participants 27.0% (n = 105 reported that themselves had been vaccinated against pandemic influenza A/H1N1. Two third (66.1% of the parents answered that they will not vaccinate their children, 21.1% already vaccinated and 12.9% were still undecided. Concern about side effect was most reported reason among who had been not vaccinated their children and among undecided parents. The second reason for refusing the pandemic vaccine was concerns efficacy of the vaccine. Media was the only source of information about pandemic influenza in nearly one third of HCWs. Agreement with vaccine safety, self receipt of pandemic influenza A/H1N1 vaccine, and trust in Ministry of Health were found to be associated with the positive attitude toward vaccinating their children against pandemic influenza A/H1N1. Conclusions Persuading parents to accept a new vaccine seems not be easy even if they are HCWs. In order to overcome the barriers among HCWs related to pandemic vaccines, determination of their misinformation, attitudes and behaviors regarding the

  15. Healthcare workers as parents: attitudes toward vaccinating their children against pandemic influenza A/H1N1.

    Science.gov (United States)

    Torun, Sebahat D; Torun, Fuat; Catak, Binali

    2010-10-10

    Both the health care workers (HCWs) and children are target groups for pandemic influenza vaccination. The coverage of the target populations is an important determinant for impact of mass vaccination. The objective of this study is to determine the attitudes of HCWs as parents, toward vaccinating their children with pandemic influenza A/H1N1 vaccine. A cross-sectional questionnaire survey was conducted with health care workers (HCWs) in a public hospital during December 2009 in Istanbul. All persons employed in the hospital with or without a health-care occupation are accepted as HCW. The HCWs who are parents of children 6 months to 18 years of age were included in the study. Pearson's chi-square test and logistic regression analysis was applied for the statistical analyses. A total of 389 HCWs who were parents of children aged 6 months-18 years participated study. Among all participants 27.0% (n = 105) reported that themselves had been vaccinated against pandemic influenza A/H1N1. Two third (66.1%) of the parents answered that they will not vaccinate their children, 21.1% already vaccinated and 12.9% were still undecided. Concern about side effect was most reported reason among who had been not vaccinated their children and among undecided parents. The second reason for refusing the pandemic vaccine was concerns efficacy of the vaccine. Media was the only source of information about pandemic influenza in nearly one third of HCWs. Agreement with vaccine safety, self receipt of pandemic influenza A/H1N1 vaccine, and trust in Ministry of Health were found to be associated with the positive attitude toward vaccinating their children against pandemic influenza A/H1N1. Persuading parents to accept a new vaccine seems not be easy even if they are HCWs. In order to overcome the barriers among HCWs related to pandemic vaccines, determination of their misinformation, attitudes and behaviors regarding the pandemic influenza vaccination is necessary. Efforts for orienting

  16. Radiological and Clinical Characteristics of a Military Outbreak of Pandemic H1N1 2009 Influenza Virus Infection

    International Nuclear Information System (INIS)

    Yun, Tae Jin; Kwon, Gu Jin; Oh, Mi Kyeong; Woo, Sung Koo; Park, Seung Hoon; Choi, Seung Hong; Lee, Hyun Ju; Goo, Jin Mo; Yim, Jae Joon; Kim, Jong Sung; Park, Chang Min

    2010-01-01

    To describe detailed clinical and radiological features of the pandemic H1N1 2009 influenza viral infection among healthy young males in a semiclosed institutionalized setting. A total of 18 patients confirmed with the pandemic H1N1 2009 influenza virus infection from July 18 to July 30, 2009 were enrolled in this study. Each patient underwent an evaluation to determine detailed clinical and radiological features. All patients presented with high fever (> 38.0..C), with accompanying symptoms of cough, rhinorrhea, sore throat, myalgia and diarrhea, and increased C-reactive protein (CRP) values with no leukocytosis nor elevated erythrocyte sedimentation rate (ESR). All patients, including one patient who progressed into acute respiratory distress syndrome, were treated with oseltamivir phosphate and quickly recovered from their symptoms. Chest radiographs showed abnormalities of small nodules and lobar consolidation in only two out of 18 patients. However, six of 12 patients who underwent thin-section CT examinations showed abnormal findings for small ground-glass opacities (GGOs) in addition to poorly-defined nodules with upper lobe predominance. In a population of healthy young adults, elevated CRP with normal ESR and white blood cell levels combined with GGOs and nodules on thin section CT scans may indicate early signs of infection by the pandemic H1N1 2009 influenza virus

  17. Compliance with recommendations for pandemic influenza H1N1 2009: the role of trust and personal beliefs.

    Science.gov (United States)

    Prati, Gabriele; Pietrantoni, Luca; Zani, Bruna

    2011-10-01

    To investigate the relationship between risk perception, worry, control, trust, exposure to an educational campaign, media exaggeration with recommendations for pandemic influenza H1N1 2009. Cross sectional telephone survey using random digit dialing. A total of 1010 adult Italians were interviewed by telephone between 16 and 19 February 2010. The survey instrument included demographic data, measures on risk perception, worry, trust and compliance with recommendations for pandemic influenza H1N1 2009. Controlling for socio-demographic variables, compliance with all the recommended behaviors was associated with media trust, trust in the Ministry of Health, worry and perceived severity of illness. Perceptions that the risk of catching pandemic influenza H1N1 2009 is high, that the authorities are acting in the public's best interest in dealing with it, that the media had exaggerated the risks of catching it and that people can control their risk of catching it were associated with compliance with some recommended behaviors even after considering effects of socio-demographic characteristics. The results underscore the importance of building public trust and to consider the influence of risk perception and affective response in promoting compliance with recommended behaviors.

  18. Molecular characterization of pandemic H1N1 influenza viruses isolated from turkeys and pathogenicity of a human pH1N1 isolate in turkeys.

    Science.gov (United States)

    Berhane, Yohannes; Ojkic, Davor; Neufeld, James; Leith, Marsha; Hisanaga, Tamiko; Kehler, Helen; Ferencz, Arpad; Wojcinski, Helen; Cottam-Birt, Colleen; Suderman, Matthew; Handel, Katherine; Alexandersen, Soren; Pasick, John

    2010-12-01

    Suspected human-to-animal transmission of the 2009 pandemic H1N1 (pH1N1) virus has been reported in several animal species, including pigs, dogs, cats, ferrets, and turkeys. In this study we describe the genetic characterization of pH1N1 viruses isolated from breeder turkeys that was associated with a progressive drop in egg production. Sequence analysis of all eight gene segments from three viruses isolated from this outbreak demonstrated homology with other human and swine pH1N1 isolates. The susceptibility of turkeys to a human pH1N1 isolate was further evaluated experimentally. The 50% turkey infectious dose (TID50) for the human isolate A/Mexico/LnDRE/4487/2009 was determined by inoculating groups of 8-10-week-old turkeys with serial 10-fold dilutions of virus by oronasal and cloacal routes. We estimated the TID50 to be between 1 x 10(5) and 1 x 10(6) TCID50. The pathogenesis of pH1N1 in oronasally or cloacally inoculated juvenile turkeys was also examined. None of the turkeys exhibited clinical signs, and no significant difference in virus shedding or seroconversion was observed between the two inoculation groups. More than 50% of the turkeys in both oronasal and cloacal groups shed virus beginning at 2 days postinoculation (dpi). All birds that actively shed virus seroconverted by 14 dpi. Virus antigen was demonstrated by immunohistochemistry in the cecal tonsils and bursa of Fabricius in two of the birds that were infected by the cloacal route. Virus transmission to naive contact turkeys was at best doubtful. This report provides additional evidence that pH1N1 can cross the species barrier and cause disease outbreaks in domestic turkeys. However, it appears that the reproductive status of the host as well as environmental factors such as concurrent infections, stress, the presence or absence of litter, and stocking density may also contribute to efficient infection and transmission of this agent.

  19. Central nervous system manifestations in pediatric patients with influenza A H1N1 infection during the 2009 pandemic.

    Science.gov (United States)

    Wilking, Ashley N; Elliott, Elizabeth; Garcia, Melissa N; Murray, Kristy O; Munoz, Flor M

    2014-09-01

    A novel H1N1 influenza A virus (A(H1N1)pdm09) particularly affected individuals central nervous system complications associated with pandemic influenza in the pediatric population. Retrospective review of patients with laboratory-confirmed influenza A(H1N1)pdm09 infection and central nervous system manifestations at Texas Children's Hospital between April 2009 and June 2010. Among 365 patients with influenza A(H1N1)pdm09, 32 (8.8%) had central nervous system manifestations at a median age of 4 years. Eight (25.0%) were previously healthy, and 12 (37.5%) had neurological pre-existing conditions. Of the 32 cases of influenza with neurological complications, seizure (n = 17; 53.1%) was the most common central nervous system manifestation, followed by encephalitis (n = 4; 12.5%), meningitis (n = 4; 12.5%), encephalopathy (n = 3; 9.4%), meningismus (n = 3; 9.4%), focal hemorrhagic brain lesions (n = 2; 6.3%), brain infarction (n = 1; 3.1%), and sensorineural hearing loss (n = 1; 3.1%). Two patients demonstrated two or more types of central nervous system complications. One patient had abnormal cerebrospinal fluid with pleocytosis. Almost two thirds of the children with central nervous system manifestations required intensive care unit admission and nearly half required mechanical ventilation. There were no deaths. Patients with pre-existing neurological conditions were at greater risk for central nervous system manifestations during pandemic influenza infection. Patients with central nervous system manifestations were more likely to experience severe illness, characterized by intensive care unit admission and mechanical ventilation, although overall outcomes were good. Influenza prevention in patients with underlying medical conditions, particularly those with neurological conditions, is important. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Value for Money in H1N1 Influenza: A Systematic Review of the Cost-Effectiveness of Pandemic Interventions.

    Science.gov (United States)

    Pasquini-Descomps, Hélène; Brender, Nathalie; Maradan, David

    2017-06-01

    The 2009 A/H1N1 influenza pandemic generated additional data and triggered new studies that opened debate over the optimal strategy for handling a pandemic. The lessons-learned documents from the World Health Organization show the need for a cost estimation of the pandemic response during the risk-assessment phase. Several years after the crisis, what conclusions can we draw from this field of research? The main objective of this article was to provide an analysis of the studies that present cost-effectiveness or cost-benefit analyses for A/H1N1 pandemic interventions since 2009 and to identify which measures seem most cost-effective. We reviewed 18 academic articles that provide cost-effectiveness or cost-benefit analyses for A/H1N1 pandemic interventions since 2009. Our review converts the studies' results into a cost-utility measure (cost per disability-adjusted life-year or quality-adjusted life-year) and presents the contexts of severity and fatality. The existing studies suggest that hospital quarantine, vaccination, and usage of the antiviral stockpile are highly cost-effective, even for mild pandemics. However, school closures, antiviral treatments, and social distancing may not qualify as efficient measures, for a virus like 2009's H1N1 and a willingness-to-pay threshold of $45,000 per disability-adjusted life-year. Such interventions may become cost-effective for severe crises. This study helps to shed light on the cost-utility of various interventions, and may support decision making, among other criteria, for future pandemics. Nonetheless, one should consider these results carefully, considering these may not apply to a specific crisis or country, and a dedicated cost-effectiveness assessment should be conducted at the time. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  1. Profile of Brazilian scientific production on A/H1N1 pandemic influenza.

    Science.gov (United States)

    Luchs, Adriana

    2012-06-01

    In the last few years, bibliometric studies have proliferated, seeking to provide data on world research. This study analyzes the profile of the Brazilian scientific production in the A (H1N1) influenza field between 2009 and 2011. The research was conducted in MEDLINE, SciELO and LILACS databases, selecting papers in which the term "H1N1" and "Brazil" were defined as the main topics. The data were analyzed taking into consideration the Brazilian state and institution in which the articles were produced, the impact factor of the journal and the language. The research revealed 40 documents (27 from MEDLINE, 16 from SciELO and 24 from LILACS). The journal impact factor ranged from 0.0977 to 8.1230. A similar amount of articles were written in English and Portuguese and São Paulo was the most productive state in the country, with 95% of the Brazilian production originating from the Southern and Southeastern regions. Linguistic data indicate that previous efforts made in order to improve the scientific production of Brazilian researchers making their observations attain a broader scientific audience produced results. It is necessary to assess the scientific studies, especially those conducted with public funds, in order to ensure that the results will benefit society.

  2. Supply of neuraminidase inhibitors related to reduced influenza A (H1N1) mortality during the 2009-2010 H1N1 pandemic: summary of an ecological study.

    Science.gov (United States)

    Miller, Paula E; Rambachan, Aksharananda; Hubbard, Roderick J; Li, Jiabai; Meyer, Alison E; Stephens, Peter; Mounts, Anthony W; Rolfes, Melissa A; Penn, Charles R

    2013-09-01

    When the influenza A (H1N1) pandemic spread across the globe from April 2009 to August 2010, many WHO Member States used antiviral drugs, specifically neuraminidase inhibitors (NAIs) oseltamivir and zanamivir, to treat influenza patients in critical condition. Antivirals have been found to be effective in reducing severity and duration of influenza illness, and likely reduce morbidity; however, it is unclear whether NAIs used during the pandemic reduced H1N1 mortality. To assess the association between antivirals and influenza mortality, at an ecologic level, country-level data on supply of oseltamivir and zanamivir were compared to laboratory-confirmed H1N1 deaths (per 100 000 people) from July 2009 to August 2010 in 42 WHO Member States. From this analysis, it was found that each 10% increase in kilograms of oseltamivir, per 100 000 people, was associated with a 1·6% reduction in H1N1 mortality over the pandemic period [relative rate (RR) = 0·84 per log increase in oseltamivir supply]. Each 10% increase in kilogram of active zanamivir, per 100 000, was associated with a 0·3% reduction in H1N1 mortality (RR = 0·97 per log increase). While limitations exist in the inference that can be drawn from an ecologic evaluation, this analysis offers evidence of a protective relationship between antiviral drug supply and influenza mortality and supports a role for influenza antiviral use in future pandemics. This article summarises the original study described previously, which can be accessed through the following citation: Miller PE, Rambachan A, Hubbard RJ, Li J, Meyer AE, et al. (2012) Supply of Neuraminidase Inhibitors Related to Reduced Influenza A (H1N1) Mortality during the 2009-2010 H1N1 Pandemic: An Ecological Study. PLoS ONE 7(9): e43491. © 2013 Blackwell Publishing Ltd.

  3. Brain magnetic resonance imaging in acute phase of pandemic influenza A (H1N1) 2009--associated encephalopathy in children.

    Science.gov (United States)

    Ishida, Yu; Kawashima, Hisashi; Morichi, Shinichiro; Yamanaka, Gaku; Okumura, Akihisa; Nakagawa, Satoshi; Morishima, Tsuneo

    2015-02-01

    Pandemic influenza A (H1N1) 2009 has been shown to be associated more with neurological complications than the seasonal influenza virus. In this study, we focused on the clinical usefulness of magnetic resonance imaging (MRI) in the acute phase of influenza A (H1N1) 2009-associated encephalopathy. A questionnaire was distributed to pediatric and general hospitals in Japan that treat children with encephalopathy. We conducted a questionnaire-based study involving the collection of information regarding 207 patients with encephalopathy. Brain MRI was performed in 97 of these 207 patients in the age group of 9 months to 15 years (mean, 7.5 years) within 48 hours after the development of encephalopathy symptoms. Sixty-six patients (68%) showed normal imaging. Diffuse brain edema was visible in five patients and an abnormal signal in the deep gray matter in two patients which is consistent with acute necrotizing encephalopathy. Abnormal signals of the splenial lesion, subcortical white matter (bright tree appearance), and cortical area were observed in 15, 1, and 8 patients, respectively. From our findings based on the questionnaire results, we suggest that MRI is useful for determining fatal cases of pandemic influenza A (H1N1) 2009 infection when performed in the acute phase. However, MRI is not useful in predicting the development of sequelae. Georg Thieme Verlag KG Stuttgart · New York.

  4. Prediction of clinical factors associated with pandemic influenza A (H1N1 2009 in Pakistan.

    Directory of Open Access Journals (Sweden)

    Nadia Nisar

    Full Text Available BACKGROUND: Influenza is a viral infection that can lead to serious complications and death(s in vulnerable groups if not diagnosed and managed in a timely manner. This study was conducted to improve the accuracy of predicting influenza through various clinical and statistical models. METHODOLOGY: A retrospective cross sectional analysis was done on demographic and epidemiological data collected from March 2009 to March 2010. Patients were classified as ILI or SARI using WHO case definitions. Respiratory specimens were tested by RT-PCR. Clinical symptoms and co-morbid conditions were analyzed using binary logistic regression models. RESULTS: In the first approach, analysis compared children (≤12 and adults (>12. Of 1,243 cases, 262 (21% tested positive for A(H1N1pdm09 and the proportion of children (≤12 and adults (>12 were 27% and 73% respectively. Four symptoms predicted influenza in children: fever (OR 2.849, 95% CI 1.931-8.722, cough (OR 1.99, 95% CI 1.512-3.643, diarrhea (OR 2.100, 95% CI 2.040-3.25 and respiratory disease (OR 3.269, 95% CI 2.128-12.624. In adults, the strongest clinical predictor was fever (OR 2.80, 95% CI 1.025-3.135 followed by cough (OR 1.431, 95% CI 1.032-2.815. In the second instance, patients were separated into two groups: SARI 326 (26% and ILI 917 (74% cases. Male to female ratio was 1.41∶1.12 for SARI and 2∶1.5 for ILI cases. Chi-square test showed that fever, cough and sore throat were significant factors for A(H1N1pdm09 infections (p = 0.008. CONCLUSION: Studies in a primary care setting should be encouraged focused on patients with influenza-like illness to develop sensitive clinical case definition that will help to improve accuracy of detecting influenza infections. Formulation of a standard "one size fits all" case definition that best correlates with influenza infections can help guide decisions for additional diagnostic testing and also discourage unjustified antibiotic prescription and usage

  5. Coordination Costs for School-Located Influenza Vaccination Clinics, Maine, 2009 H1N1 Pandemic

    Science.gov (United States)

    Asay, Garrett R. Beeler; Cho, Bo-Hyun; Lorick, Suchita A.; Tipton, Meredith L.; Dube, Nancy L.; Messonnier, Mark L.

    2012-01-01

    School nurses played a key role in Maine's school-located influenza vaccination (SLV) clinics during the 2009-2010 pandemic season. The objective of this study was to determine, from the school district perspective, the labor hours and costs associated with outside-clinic coordination activities (OCA). The authors defined OCA as labor hours spent…

  6. Seasonal influenza vaccine and protection against pandemic (H1N1 2009-associated illness among US military personnel.

    Directory of Open Access Journals (Sweden)

    Matthew C Johns

    Full Text Available INTRODUCTION: A novel A/H1N1 virus is the cause of the present influenza pandemic; vaccination is a key countermeasure, however, few data assessing prior seasonal vaccine effectiveness (VE against the pandemic strain of H1N1 (pH1N1 virus are available. MATERIALS AND METHODS: Surveillance of influenza-related medical encounter data of active duty military service members stationed in the United States during the period of April-October 2009 with comparison of pH1N1-confirmed cases and location and date-matched controls. Crude odds ratios (OR and VE estimates for immunized versus non-immunized were calculated as well as adjusted OR (AOR controlling for sex, age group, and history of prior influenza vaccination. Separate stratified VE analyses by vaccine type (trivalent inactivated [TIV] or live attenuated [LAIV], age groups and hospitalization status were also performed. For the period of April 20 to October 15, 2009, a total of 1,205 cases of pH1N1-confirmed cases were reported, 966 (80% among males and over one-half (58% under 25 years of age. Overall VE for service members was found to be 45% (95% CI, 33 to 55%. Immunization with prior season's TIV (VE = 44%, 95% CI, 32 to 54% as well as LAIV (VE = 24%, 95% CI, 6 to 38% were both found to be associated with protection. Of significance, VE against a severe disease outcome was higher (VE = 62%, 95% CI, 14 to 84% than against milder outcomes (VE = 42%, 95% CI, 29 to 53%. CONCLUSION: A moderate association with protection against clinically apparent, laboratory-confirmed Pandemic (H1N1 2009-associated illness was found for immunization with either TIV or LAIV 2008-09 seasonal influenza vaccines. This association with protection was found to be especially apparent for severe disease as compared to milder outcome, as well as in the youngest and older populations. Prior vaccination with seasonal influenza vaccines in 2004-08 was also independently associated with protection.

  7. Antiviral therapy and outcomes of patients with pneumonia caused by influenza A pandemic (H1N1 virus.

    Directory of Open Access Journals (Sweden)

    Shi-gui Yang

    Full Text Available BACKGROUND: There is limited data on the clinical outcome of patients with pandemic H1N1 (pH1N1 pneumonia who received oseltamivir treatment, especially when the treatment was administered more than 48 hours after symptom onset. METHODS: During the pandemic in 2009, a cohort of pH1N1 influenza pneumonia was built in China, and their clinical information was collected systematically, and analyzed with Cox models. RESULTS: 920 adults and 541 children with pneumonia who didn't receive corticosteroids were analyzed. In-hospital mortality was higher in adults who did not receive antiviral therapy (18.2% than those with who received oseltamivir ≤ 2 days (2.9%, between 2-5 days (4.6% and >5 days after illness onset (4.9%, p5 days, respectively. For males patients, aged ≥ 14 years and baseline PaO(2/FiO(23.8 mg/kg/d did not improve clinical outcome (mortality, higher dose 2.5% vs standard dose 2.8%, p>0.05. CONCLUSIONS: Antiviral therapy might reduce mortality of patients with pH1N1 pneumonia, even when initiated more than 48 hours after onset of illness. Greater protective effects might be in males, patients aged 14-60 years, and patients with PaO(2/FiO(2<200.

  8. Efficacy of a pandemic (H1N1) 2009 virus vaccine in pigs against the pandemic influenza virus is superior to commercially available swine influenza vaccines.

    Science.gov (United States)

    Loeffen, W L A; Stockhofe, N; Weesendorp, E; van Zoelen-Bos, D; Heutink, R; Quak, S; Goovaerts, D; Heldens, J G M; Maas, R; Moormann, R J; Koch, G

    2011-09-28

    In April 2009 a new influenza A/H1N1 strain, currently named "pandemic (H1N1) influenza 2009" (H1N1v), started the first official pandemic in humans since 1968. Several incursions of this virus in pig herds have also been reported from all over the world. Vaccination of pigs may be an option to reduce exposure of human contacts with infected pigs, thereby preventing cross-species transfer, but also to protect pigs themselves, should this virus cause damage in the pig population. Three swine influenza vaccines, two of them commercially available and one experimental, were therefore tested and compared for their efficacy against an H1N1v challenge. One of the commercial vaccines is based on an American classical H1N1 influenza strain, the other is based on a European avian H1N1 influenza strain. The experimental vaccine is based on reassortant virus NYMC X179A (containing the hemagglutinin (HA) and neuraminidase (NA) genes of A/California/7/2009 (H1N1v) and the internal genes of A/Puerto Rico/8/34 (H1N1)). Excretion of infectious virus was reduced by 0.5-3 log(10) by the commercial vaccines, depending on vaccine and sample type. Both vaccines were able to reduce virus replication especially in the lower respiratory tract, with less pathological lesions in vaccinated and subsequently challenged pigs than in unvaccinated controls. In pigs vaccinated with the experimental vaccine, excretion levels of infectious virus in nasal and oropharyngeal swabs, were at or below 1 log(10)TCID(50) per swab and lasted for only 1 or 2 days. An inactivated vaccine containing the HA and NA of an H1N1v is able to protect pigs from an infection with H1N1v, whereas swine influenza vaccines that are currently available are of limited efficaciousness. Whether vaccination of pigs against H1N1v will become opportune remains to be seen and will depend on future evolution of this strain in the pig population. Close monitoring of the pig population, focussing on presence and evolution of

  9. Transmission characteristics of the 2009 H1N1 influenza pandemic: comparison of 8 Southern hemisphere countries.

    Directory of Open Access Journals (Sweden)

    Lulla Opatowski

    2011-09-01

    Full Text Available While in Northern hemisphere countries, the pandemic H1N1 virus (H1N1pdm was introduced outside of the typical influenza season, Southern hemisphere countries experienced a single wave of transmission during their 2009 winter season. This provides a unique opportunity to compare the spread of a single virus in different countries and study the factors influencing its transmission. Here, we estimate and compare transmission characteristics of H1N1pdm for eight Southern hemisphere countries/states: Argentina, Australia, Bolivia, Brazil, Chile, New Zealand, South Africa and Victoria (Australia. Weekly incidence of cases and age-distribution of cumulative cases were extracted from public reports of countries' surveillance systems. Estimates of the reproduction numbers, R(0, empirically derived from the country-epidemics' early exponential phase, were positively associated with the proportion of children in the populations (p = 0.004. To explore the role of demography in explaining differences in transmission intensity, we then fitted a dynamic age-structured model of influenza transmission to available incidence data for each country independently, and for all the countries simultaneously. Posterior median estimates of R₀ ranged 1.2-1.8 for the country-specific fits, and 1.29-1.47 for the global fits. Corresponding estimates for overall attack-rate were in the range 20-50%. All model fits indicated a significant decrease in susceptibility to infection with age. These results confirm the transmissibility of the 2009 H1N1 pandemic virus was relatively low compared with past pandemics. The pattern of age-dependent susceptibility found confirms that older populations had substantial--though partial--pre-existing immunity, presumably due to exposure to heterologous influenza strains. Our analysis indicates that between-country-differences in transmission were at least partly due to differences in population demography.

  10. Cost-effectiveness of 2009 pandemic influenza A(H1N1 vaccination in the United States.

    Directory of Open Access Journals (Sweden)

    Lisa A Prosser

    Full Text Available Pandemic influenza A(H1N1 (pH1N1 was first identified in North America in April 2009. Vaccination against pH1N1 commenced in the U.S. in October 2009 and continued through January 2010. The objective of this study was to evaluate the cost-effectiveness of pH1N1 vaccination.A computer simulation model was developed to predict costs and health outcomes for a pH1N1 vaccination program using inactivated vaccine compared to no vaccination. Probabilities, costs and quality-of-life weights were derived from emerging primary data on pH1N1 infections in the US, published and unpublished data for seasonal and pH1N1 illnesses, supplemented by expert opinion. The modeled target population included hypothetical cohorts of persons aged 6 months and older stratified by age and risk. The analysis used a one-year time horizon for most endpoints but also includes longer-term costs and consequences of long-term sequelae deaths. A societal perspective was used. Indirect effects (i.e., herd effects were not included in the primary analysis. The main endpoint was the incremental cost-effectiveness ratio in dollars per quality-adjusted life year (QALY gained. Sensitivity analyses were conducted.For vaccination initiated prior to the outbreak, pH1N1 vaccination was cost-saving for persons 6 months to 64 years under many assumptions. For those without high risk conditions, incremental cost-effectiveness ratios ranged from $8,000-$52,000/QALY depending on age and risk status. Results were sensitive to the number of vaccine doses needed, costs of vaccination, illness rates, and timing of vaccine delivery.Vaccination for pH1N1 for children and working-age adults is cost-effective compared to other preventive health interventions under a wide range of scenarios. The economic evidence was consistent with target recommendations that were in place for pH1N1 vaccination. We also found that the delays in vaccine availability had a substantial impact on the cost-effectiveness of

  11. Specific Inhibitory Effect of κ-Carrageenan Polysaccharide on Swine Pandemic 2009 H1N1 Influenza Virus.

    Directory of Open Access Journals (Sweden)

    Qiang Shao

    Full Text Available The 2009 influenza A H1N1 pandemic placed unprecedented demands on antiviral drug resources and the vaccine industry. Carrageenan, an extractive of red algae, has been proven to inhibit infection and multiplication of various enveloped viruses. The aim of this study was to examine the ability of κ-carrageenan to inhibit swine pandemic 2009 H1N1 influenza virus to gain an understanding of antiviral ability of κ-carrageenan. It was here demonstrated that κ-carrageenan had no cytotoxicity at concentrations below 1000 μg/ml. Hemagglutination, 50% tissue culture infectious dose (TCID50 and cytopathic effect (CPE inhibition assays showed that κ-carrageenan inhibited A/Swine/Shandong/731/2009 H1N1 (SW731 and A/California/04/2009 H1N1 (CA04 replication in a dose-dependent fashion. Mechanism studies show that the inhibition of SW731 multiplication and mRNA expression was maximized when κ-carrageenan was added before or during adsorption. The result of Hemagglutination inhibition assay indicate that κ-carrageenan specifically targeted HA of SW731 and CA04, both of which are pandemic H1N/2009 viruses, without effect on A/Pureto Rico/8/34 H1N1 (PR8, A/WSN/1933 H1N1 (WSN, A/Swine/Beijing/26/2008 H1N1 (SW26, A/Chicken/Shandong/LY/2008 H9N2 (LY08, and A/Chicken/Shandong/ZB/2007 H9N2 (ZB07 viruses. Immunofluorescence assay and Western blot showed that κ-carrageenan also inhibited SW731 protein expression after its internalization into cells. These results suggest that κ-carrageenan can significantly inhibit SW731 replication by interfering with a few replication steps in the SW731 life cycles, including adsorption, transcription, and viral protein expression, especially interactions between HA and cells. In this way, κ-carrageenan might be a suitable alternative approach to therapy meant to address anti-IAV, which contains an HA homologous to that of SW731.

  12. Pandemic H1N1 influenza A directly induces a robust and acute inflammatory gene signature in primary human bronchial epithelial cells downstream of membrane fusion

    Energy Technology Data Exchange (ETDEWEB)

    Paquette, Stéphane G. [Division of Experimental Therapeutics, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario (Canada); Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, Ontario (Canada); Banner, David [Division of Experimental Therapeutics, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario (Canada); Chi, Le Thi Bao [Department of Microbiology, Hue University of Medicine and Pharmacy, Thua Thien Hue (Viet Nam); Carlo Urbani Centre, Hue University of Medicine and Pharmacy, Thua Thien Hue (Viet Nam); Leon, Alberto J. [Division of Experimental Therapeutics, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario (Canada); International Institute of Infection and Immunity, Shantou University Medical College, Shantou, Guangdong (China); Xu, Luoling; Ran, Longsi [Division of Experimental Therapeutics, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario (Canada); Huang, Stephen S.H. [Division of Experimental Therapeutics, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario (Canada); Department of Immunology, Faculty of Medicine, University of Toronto, Toronto, Ontario (Canada); Farooqui, Amber [Division of Experimental Therapeutics, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario (Canada); International Institute of Infection and Immunity, Shantou University Medical College, Shantou, Guangdong (China); and others

    2014-01-05

    Pandemic H1N1 influenza A (H1N1pdm) elicits stronger pulmonary inflammation than previously circulating seasonal H1N1 influenza A (sH1N1), yet mechanisms of inflammatory activation in respiratory epithelial cells during H1N1pdm infection are unclear. We investigated host responses to H1N1pdm/sH1N1 infection and virus entry mechanisms in primary human bronchial epithelial cells in vitro. H1N1pdm infection rapidly initiated a robust inflammatory gene signature (3 h post-infection) not elicited by sH1N1 infection. Protein secretion inhibition had no effect on gene induction. Infection with membrane fusion deficient H1N1pdm failed to induce robust inflammatory gene expression which was rescued with restoration of fusion ability, suggesting H1N1pdm directly triggered the inflammatory signature downstream of membrane fusion. Investigation of intra-virion components revealed H1N1pdm viral RNA (vRNA) triggered a stronger inflammatory phenotype than sH1N1 vRNA. Thus, our study is first to report H1N1pdm induces greater inflammatory gene expression than sH1N1 in vitro due to direct virus–epithelial cell interaction. - Highlights: • We investigated H1N1pdm/sH1N1 infection in primary epithelial cells. • H1N1pdm directly initiated a robust inflammatory gene signature, sH1N1 did not. • H1N1pdm viral RNA triggered a stronger response than sH1N1. • H1N1pdm induces greater response due to direct virus–cell interaction. • These results have potential to impact vaccine and therapeutic development.

  13. Pandemic H1N1 influenza A directly induces a robust and acute inflammatory gene signature in primary human bronchial epithelial cells downstream of membrane fusion

    International Nuclear Information System (INIS)

    Paquette, Stéphane G.; Banner, David; Chi, Le Thi Bao; Leon, Alberto J.; Xu, Luoling; Ran, Longsi; Huang, Stephen S.H.; Farooqui, Amber

    2014-01-01

    Pandemic H1N1 influenza A (H1N1pdm) elicits stronger pulmonary inflammation than previously circulating seasonal H1N1 influenza A (sH1N1), yet mechanisms of inflammatory activation in respiratory epithelial cells during H1N1pdm infection are unclear. We investigated host responses to H1N1pdm/sH1N1 infection and virus entry mechanisms in primary human bronchial epithelial cells in vitro. H1N1pdm infection rapidly initiated a robust inflammatory gene signature (3 h post-infection) not elicited by sH1N1 infection. Protein secretion inhibition had no effect on gene induction. Infection with membrane fusion deficient H1N1pdm failed to induce robust inflammatory gene expression which was rescued with restoration of fusion ability, suggesting H1N1pdm directly triggered the inflammatory signature downstream of membrane fusion. Investigation of intra-virion components revealed H1N1pdm viral RNA (vRNA) triggered a stronger inflammatory phenotype than sH1N1 vRNA. Thus, our study is first to report H1N1pdm induces greater inflammatory gene expression than sH1N1 in vitro due to direct virus–epithelial cell interaction. - Highlights: • We investigated H1N1pdm/sH1N1 infection in primary epithelial cells. • H1N1pdm directly initiated a robust inflammatory gene signature, sH1N1 did not. • H1N1pdm viral RNA triggered a stronger response than sH1N1. • H1N1pdm induces greater response due to direct virus–cell interaction. • These results have potential to impact vaccine and therapeutic development

  14. 2009 pandemic influenza A (H1N1 virus outbreak and response--Rwanda, October, 2009-May, 2010.

    Directory of Open Access Journals (Sweden)

    Justin Wane

    Full Text Available BACKGROUND: In October 2009, the first case of pandemic influenza A(H1N1pdm09 (pH1N1 was confirmed in Kigali, Rwanda and countrywide dissemination occurred within several weeks. We describe clinical and epidemiological characteristics of this epidemic. METHODS: From October 2009 through May 2010, we undertook epidemiologic investigations and response to pH1N1. Respiratory specimens were collected from all patients meeting the WHO case definition for pH1N1, which were tested using CDC's real time RT-PCR protocol at the Rwandan National Reference Laboratory (NRL. Following documented viral transmission in the community, testing focused on clinically severe and high-risk group suspect cases. RESULTS: From October 9, 2009 through May 31, 2010, NRL tested 2,045 specimens. In total, 26% (n = 532 of specimens tested influenza positive; of these 96% (n = 510 were influenza A and 4% (n = 22 were influenza B. Of cases testing influenza A positive, 96.8% (n = 494, 3% (n = 15, and 0.2% (n = 1 were A(H1N1pdm09, Seasonal A(H3 and Seasonal A(non-subtyped, respectively. Among laboratory-confirmed cases, 263 (53.2% were children <15 years and 275 (52% were female. In total, 58 (12% cases were hospitalized with mean duration of hospitalization of 5 days (Range: 2-15 days. All cases recovered and there were no deaths. Overall, 339 (68% confirmed cases received oseltamivir in any setting. Among all positive cases, 26.9% (143/532 were among groups known to be at high risk of influenza-associated complications, including age <5 years 23% (122/532, asthma 0.8% (4/532, cardiac disease 1.5% (8/532, pregnancy 0.6% (3/532, diabetes mellitus 0.4% (2/532, and chronic malnutrition 0.8% (4/532. CONCLUSIONS: Rwanda experienced a PH1N1 outbreak which was epidemiologically similar to PH1N1 outbreaks in the region. Unlike seasonal influenza, children <15 years were the most affected by pH1N1. Lessons learned from the outbreak response included the need to

  15. Cytokine response patterns in severe pandemic 2009 H1N1 and seasonal influenza among hospitalized adults.

    Directory of Open Access Journals (Sweden)

    Nelson Lee

    Full Text Available BACKGROUND: Studying cytokine/chemokine responses in severe influenza infections caused by different virus subtypes may improve understanding on pathogenesis. METHODS: Adults hospitalized for laboratory-confirmed seasonal and pandemic 2009 A/H1N1 (pH1N1 influenza were studied. Plasma concentrations of 13 cytokines/chemokines were measured at presentation and then serially, using cytometric-bead-array with flow-cytometry and ELISA. PBMCs from influenza patients were studied for cytokine/chemokine expression using ex-vivo culture (Whole Blood Assay,±PHA/LPS stimulation. Clinical variables were prospectively recorded and analyzed. RESULTS: 63 pH1N1 and 53 seasonal influenza patients were studied. pH1N1 patients were younger (mean±S.D. 42.8±19.2 vs 70.5±16.7 years, and fewer had comorbidities. Respiratory/cardiovascular complications were common in both groups (71.4% vs 81.1%, although severe pneumonia with hypoxemia (54.0% vs 28.3% and ICU admissions (25.4% vs 1.9% were more frequent with pH1N1. Hyperactivation of the proinflammatory cytokines IL-6, CXCL8/IL-8, CCL2/MCP-1 and sTNFR-1 was found in pH1N1 pneumonia (2-15 times normal and in complicated seasonal influenza, but not in milder pH1N1 infections. The adaptive-immunity (Th1/Th17-related CXCL10/IP-10, CXCL9/MIG and IL-17A however, were markedly suppressed in severe pH1N1 pneumonia (2-27 times lower than seasonal influenza; P-values<0.01. This pattern was further confirmed with serial measurements. Hypercytokinemia tended to be sustained in pH1N1 pneumonia, associated with a slower viral clearance [PCR-negativity: day 3-4, 55% vs 85%; day 6-7, 67% vs 100%]. Elevated proinflammatory cytokines, particularly IL-6, predicted ICU admission (adjusted OR 12.6, 95%CI 2.6-61.5, per log(10unit increase; P = 0.002, and correlated with fever, tachypnoea, deoxygenation, and length-of-stay (Spearman's rho, P-values<0.01 in influenza infections. PBMCs in seasonal influenza patients were activated and

  16. Toward a method for tracking virus evolutionary trajectory applied to the pandemic H1N1 2009 influenza virus.

    Science.gov (United States)

    Squires, R Burke; Pickett, Brett E; Das, Sajal; Scheuermann, Richard H

    2014-12-01

    In 2009 a novel pandemic H1N1 influenza virus (H1N1pdm09) emerged as the first official influenza pandemic of the 21st century. Early genomic sequence analysis pointed to the swine origin of the virus. Here we report a novel computational approach to determine the evolutionary trajectory of viral sequences that uses data-driven estimations of nucleotide substitution rates to track the gradual accumulation of observed sequence alterations over time. Phylogenetic analysis and multiple sequence alignments show that sequences belonging to the resulting evolutionary trajectory of the H1N1pdm09 lineage exhibit a gradual accumulation of sequence variations and tight temporal correlations in the topological structure of the phylogenetic trees. These results suggest that our evolutionary trajectory analysis (ETA) can more effectively pinpoint the evolutionary history of viruses, including the host and geographical location traversed by each segment, when compared against either BLAST or traditional phylogenetic analysis alone. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Productive infection of human skeletal muscle cells by pandemic and seasonal influenza A(H1N1 viruses.

    Directory of Open Access Journals (Sweden)

    Marion Desdouits

    Full Text Available Besides the classical respiratory and systemic symptoms, unusual complications of influenza A infection in humans involve the skeletal muscles. Numerous cases of acute myopathy and/or rhabdomyolysis have been reported, particularly following the outbreak of pandemic influenza A(H1N1 in 2009. The pathogenesis of these influenza-associated myopathies (IAM remains unkown, although the direct infection of muscle cells is suspected. Here, we studied the susceptibility of cultured human primary muscle cells to a 2009 pandemic and a 2008 seasonal influenza A(H1N1 isolate. Using cells from different donors, we found that differentiated muscle cells (i. e. myotubes were highly susceptible to infection by both influenza A(H1N1 isolates, whereas undifferentiated cells (i. e. myoblasts were partially resistant. The receptors for influenza viruses, α2-6 and α2-3 linked sialic acids, were detected on the surface of myotubes and myoblasts. Time line of viral nucleoprotein (NP expression and nuclear export showed that the first steps of the viral replication cycle could take place in muscle cells. Infected myotubes and myoblasts exhibited budding virions and nuclear inclusions as observed by transmission electron microscopy and correlative light and electron microscopy. Myotubes, but not myoblasts, yielded infectious virus progeny that could further infect naive muscle cells after proteolytic treatment. Infection led to a cytopathic effect with the lysis of muscle cells, as characterized by the release of lactate dehydrogenase. The secretion of proinflammatory cytokines by muscle cells was not affected following infection. Our results are compatible with the hypothesis of a direct muscle infection causing rhabdomyolysis in IAM patients.

  18. Detection of extensive cross-neutralization between pandemic and seasonal A/H1N1 Influenza Viruses using a pseudotype neutralization assay.

    Directory of Open Access Journals (Sweden)

    Béatrice Labrosse

    Full Text Available BACKGROUND: Cross-immunity between seasonal and pandemic A/H1N1 influenza viruses remains uncertain. In particular, the extent that previous infection or vaccination by seasonal A/H1N1 viruses can elicit protective immunity against pandemic A/H1N1 is unclear. METHODOLOGY/PRINCIPAL FINDINGS: Neutralizing titers against seasonal A/H1N1 (A/Brisbane/59/2007 and against pandemic A/H1N1 (A/California/04/2009 were measured using an HIV-1-based pseudovirus neutralization assay. Using this highly sensitive assay, we found that a large fraction of subjects who had never been exposed to pandemic A/H1N1 express high levels of pandemic A/H1N1 neutralizing titers. A significant correlation was seen between neutralization of pandemic A/H1N1 and neutralization of a standard seasonal A/H1N1 strain. Significantly higher pandemic A/H1N1 neutralizing titers were measured in subjects who had received vaccination against seasonal influenza in 2008-2009. Higher pandemic neutralizing titers were also measured in subjects over 60 years of age. CONCLUSIONS/SIGNIFICANCE: Our findings reveal that the extent of protective cross-immunity between seasonal and pandemic A/H1N1 influenza viruses may be more important than previously estimated. This cross-immunity could provide a possible explanation of the relatively mild profile of the recent influenza pandemic.

  19. Structural Characterization of the Hemagglutinin Receptor Specificity from the 2009 H1N1 Influenza Pandemic

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Rui; McBride, Ryan; Nycholat, Corwin M.; Paulson, James C.; Wilson, Ian A. (Scripps)

    2012-02-13

    Influenza virus hemagglutinin (HA) is the viral envelope protein that mediates viral attachment to host cells and elicits membrane fusion. The HA receptor-binding specificity is a key determinant for the host range and transmissibility of influenza viruses. In human pandemics of the 20th century, the HA normally has acquired specificity for human-like receptors before widespread infection. Crystal structures of the H1 HA from the 2009 human pandemic (A/California/04/2009 [CA04]) in complex with human and avian receptor analogs reveal conserved recognition of the terminal sialic acid of the glycan ligands. However, favorable interactions beyond the sialic acid are found only for {alpha}2-6-linked glycans and are mediated by Asp190 and Asp225, which hydrogen bond with Gal-2 and GlcNAc-3. For {alpha}2-3-linked glycan receptors, no specific interactions beyond the terminal sialic acid are observed. Our structural and glycan microarray analyses, in the context of other high-resolution HA structures with {alpha}2-6- and {alpha}2-3-linked glycans, now elucidate the structural basis of receptor-binding specificity for H1 HAs in human and avian viruses and provide a structural explanation for the preference for {alpha}2-6 siaylated glycan receptors for the 2009 pandemic swine flu virus.

  20. From press release to news: mapping the framing of the 2009 H1N1 A influenza pandemic.

    Science.gov (United States)

    Lee, Seow Ting; Basnyat, Iccha

    2013-01-01

    Pandemics challenge conventional assumptions about health promotion, message development, community engagement, and the role of news media. To understand the use of press releases in news coverage of pandemics, this study traces the development of framing devices from a government public health agency's press releases to news stories about the 2009 H1N1 A influenza pandemic. The communication management of the H1N1 pandemic, an international news event with local implications, by the Singapore government is a rich locus for understanding the dynamics of public relations, health communication, and journalism. A content analysis shows that the evolution of information from press release to news is marked by significant changes in media frames, including the expansion and diversification in dominant frames and emotion appeals, stronger thematic framing, more sources of information, conversion of loss frames into gain frames, and amplification of positive tone favoring the public health agency's position. Contrary to previous research that suggests that government information subsidies passed almost unchanged through media gatekeepers, the news coverage of the pandemic reflects journalists' selectivity in disseminating the government press releases and in mediating the information flow and frames from the press releases.

  1. Clinical and radiological features of pandemic H1N1 2009 influenza virus infection manifesting as acute febrile respiratory illness at their initial presentations: comparison with contemporaneous non-H1N1 patients

    International Nuclear Information System (INIS)

    Yun, Tae Jin; Park, Chang Min; Choi, Seung Hong; Lee, Hyun Ju; Goo, Jin Mo; Kwon, Gu Jin; Woo, Sung Koo; Park, Seung Hoon

    2011-01-01

    Background Since the first outbreak caused by the pandemic H1N1 2009 influenza in Mexico, the virus has spread widely across the world with meaningful morbidity and mortality. However, there are few data on the comparative investigations to assess the clinical and radiological features between the H1N1 patient and non-H1N1 patients. Purpose To assess the clinical and radiological features of patients infected by the pandemic H1N1 2009 flu virus at their initial presentation and to compare them with contemporaneous non-H1N1 patients with acute febrile respiratory illness. Material and Methods This retrospective study was approved by the ethics committee of the Armed Forces Medical Command, South Korea. From August to September 2009, 337 consecutive patients presented with an acute febrile respiratory illness in a tertiary military hospital. Reverse-transcriptase polymerase-chain-reaction tests were performed in 62 of these patients under the impression of H1N1 infection. Clinical and radiological features at their initial presentation were described for the H1N1 group (n = 35) and non-H1N1 group (n = 27) and compared between the two groups. Results Increased C-reactive protein level (97%) without leukocytosis (9%) or increased erythrocyte sedimentation rate (0%) was common in the H1N1 group at their initial presentation. On chest radiographs, 12 of 35 (34%) H1N1 patients had abnormal findings; nodules in 10 patients (83%) and consolidations in two (17%). Of the 28 H1N1 patients who underwent thin-section CT 16 patients (57%) showed abnormal findings; ground-glass opacities (GGOs) in 15 (94%), and nodules in 13 (81%). However, there were no significant differences between the H1N1 group and non-H1N1 group in terms of symptoms, laboratory results, or radiological findings (P > 0.05). Conclusion Patients with H1N1 infection show consistent clinical and radiological features at their initial presentation, however, clinical and radiological features of the H1N1 group are

  2. Clinical and radiological features of pandemic H1N1 2009 influenza virus infection manifesting as acute febrile respiratory illness at their initial presentations: comparison with contemporaneous non-H1N1 patients

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Tae Jin (Dept. of Radiology, Armed Force Byukjae Hospital, Gyeonggi-do (Korea, Republic of); Dept. of Radiology, Seoul National Univ. Hospital, Seoul (Korea, Republic of)); Park, Chang Min; Choi, Seung Hong; Lee, Hyun Ju; Goo, Jin Mo (Dept. of Radiology, Seoul National Univ. Hospital, Seoul (Korea, Republic of)), email: cmpark@radiol.snu.ac.kr; Kwon, Gu Jin (Dept. of Family Medicine, Armed Force Byukjae Hospital, Gyeonggi-do (Korea, Republic of); Dept. of Family Medicine, Gangneung Asan Hospital, Gangneung (Korea, Republic of)); Woo, Sung Koo (Dept. of Radiology, Armed Force Byukjae Hospital, Gyeonggi-do (Korea, Republic of)); Park, Seung Hoon (Dept. of Internal Medicine, Armed Force Byukjae Hospital, Gyeonggi-do (Korea, Republic of))

    2011-05-15

    Background Since the first outbreak caused by the pandemic H1N1 2009 influenza in Mexico, the virus has spread widely across the world with meaningful morbidity and mortality. However, there are few data on the comparative investigations to assess the clinical and radiological features between the H1N1 patient and non-H1N1 patients. Purpose To assess the clinical and radiological features of patients infected by the pandemic H1N1 2009 flu virus at their initial presentation and to compare them with contemporaneous non-H1N1 patients with acute febrile respiratory illness. Material and Methods This retrospective study was approved by the ethics committee of the Armed Forces Medical Command, South Korea. From August to September 2009, 337 consecutive patients presented with an acute febrile respiratory illness in a tertiary military hospital. Reverse-transcriptase polymerase-chain-reaction tests were performed in 62 of these patients under the impression of H1N1 infection. Clinical and radiological features at their initial presentation were described for the H1N1 group (n = 35) and non-H1N1 group (n = 27) and compared between the two groups. Results Increased C-reactive protein level (97%) without leukocytosis (9%) or increased erythrocyte sedimentation rate (0%) was common in the H1N1 group at their initial presentation. On chest radiographs, 12 of 35 (34%) H1N1 patients had abnormal findings; nodules in 10 patients (83%) and consolidations in two (17%). Of the 28 H1N1 patients who underwent thin-section CT 16 patients (57%) showed abnormal findings; ground-glass opacities (GGOs) in 15 (94%), and nodules in 13 (81%). However, there were no significant differences between the H1N1 group and non-H1N1 group in terms of symptoms, laboratory results, or radiological findings (P > 0.05). Conclusion Patients with H1N1 infection show consistent clinical and radiological features at their initial presentation, however, clinical and radiological features of the H1N1 group are

  3. Neuraminidase and hemagglutinin matching patterns of a highly pathogenic avian and two pandemic H1N1 influenza A viruses.

    Directory of Open Access Journals (Sweden)

    Yonghui Zhang

    Full Text Available BACKGROUND: Influenza A virus displays strong reassortment characteristics, which enable it to achieve adaptation in human infection. Surveying the reassortment and virulence of novel viruses is important in the prevention and control of an influenza pandemic. Meanwhile, studying the mechanism of reassortment may accelerate the development of anti-influenza strategies. METHODOLOGY/PRINCIPAL FINDINGS: The hemagglutinin (HA and neuraminidase (NA matching patterns of two pandemic H1N1 viruses (the 1918 and current 2009 strains and a highly pathogenic avian influenza A virus (H5N1 were studied using a pseudotyped particle (pp system. Our data showed that four of the six chimeric HA/NA combinations could produce infectious pps, and that some of the chimeric pps had greater infectivity than did their ancestors, raising the possibility of reassortment among these viruses. The NA of H5N1 (A/Anhui/1/2005 could hardly reassort with the HAs of the two H1N1 viruses. Many biological characteristics of HA and NA, including infectivity, hemagglutinating ability, and NA activity, are dependent on their matching pattern. CONCLUSIONS/SIGNIFICANCE: Our data suggest the existence of an interaction between HA and NA, and the HA NA matching pattern is critical for valid viral reassortment.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Xueli Zhao

    Full Text Available 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.

  6. A seroepidemiological study of pandemic A/H1N1(2009) influenza in a rural population of Mali.

    Science.gov (United States)

    Koita, O A; Sangare, L; Poudiougou, B; Aboubacar, B; Samake, Y; Coulibaly, T; Pronyk, P; Salez, N; Kieffer, A; Ninove, L; Flahault, A; de Lamballerie, X

    2012-10-01

    The swine-origin H1N1 influenza A virus (pH1N1(2009)) started to circulate worldwide in 2009, and cases were notified in a number of sub-Saharan African countries. However, no epidemiological data allowing estimation of the epidemic burden were available in this region, preventing comprehensive comparisons with other parts of the world. The CoPanFlu-Mali programme studied a cohort of 202 individuals living in the rural commune of Dioro (southern central Mali). Pre-pandemic and post-pandemic paired sera (sampled in 2006 and April 2010, respectively) were tested by the haemagglutination inhibition (HI) method. Different estimates of pH1N1(2009) infection during the 2009 first epidemic wave were used (increased prevalence of HI titre of ≥1/40 or ≥1/80, seroconversions) and provided convergent attack rate values (12.4-14.9%), the highest values being observed in the 0-19-year age group (16.0-18.4%). In all age groups, pre-pandemic HI titres of ≥1/40 were associated with complete absence of seroconversion; and geometric mean titres were 20 in others. Important variations in seroconversion rate existed among the different villages investigated. Despite limitations resulting from the size and composition of the sample analysed, this study provides strong evidence that the impact of the pH1N1(2009) first wave was more important than previously believed, and that the determinants of the epidemic spread in sub-Saharan populations were quite different from those observed in developed countries. © 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.

  7. The new school absentees reporting system for pandemic influenza A/H1N1 2009 infection in Japan.

    Directory of Open Access Journals (Sweden)

    Takeshi Suzue

    Full Text Available To evaluate the new Japanese School Absentees Reporting System for Infectious Disease (SARSID for pandemic influenza A/H1N1 2009 infection in comparison with the National epidemiological Surveillance of Infectious Disease (NESID.We used data of 53,223 students (97.7% in Takamatsu city Japan. Data regarding school absentees in SARSID was compared with that in NESID from Oct 13, 2009 to Jan 12, 2010.Similar trends were observed both in SARSID and NESID. However, the epidemic trend for influenza in SARSID was thought to be more sensitive than that in NESID.The epidemic trend for influenza among school-aged children could be easily and rapidly assessed by SARSID compared to NESID. SARSID might be useful for detecting the epidemic trend of influenza.

  8. Will the community nurse continue to function during H1N1 influenza pandemic: a cross-sectional study of Hong Kong community nurses?

    Science.gov (United States)

    Wong, Eliza L Y; Wong, Samuel Y S; Kung, Kenny; Cheung, Annie W L; Gao, Tiffany T; Griffiths, Sian

    2010-04-30

    Healthcare workers have been identified as one of the high risk groups for being infected with influenza during influenza pandemic. Potential levels of absenteeism among healthcare workers in hospital settings are high. However, there was no study to explore the attitudes of healthcare workers in community setting towards the preparedness to the novel H1N1 influenza pandemic. The aim of this study was to explore the willingness of community nurses in Hong Kong to work during H1N1 influenza pandemic. A cross-sectional survey was conducted among all 401 community nurses employed by the Hospital Authority in Hong Kong when the WHO pandemic alert level was 6. The response rate of this study was 66.6%. 76.9% participants reported being "not willing" (33.3%) or "not sure" (43.6%) to take care of patients during H1N1 influenza pandemic. The self-reported reasons for being unwilling to report to duty during H1N1 influenza pandemic were psychological stress (55.0%) and fear of being infected H1N1 influenza (29.2%). The reported unwillingness to report to duty was marginally significantly associated with the request for further training of using infection control clinical guideline (OR: 0.057; CI: 0.25-1.02). Those who reported unwillingness or not being sure about taking care of the patients during H1N1 influenza pandemic were more depressed (p work more emotionally stressful (p < 0.001). Interventions to provide infection control training and address community nurses' psychological needs might increase their willingness to provide care to patients in the community during H1N1 influenza pandemic. This would help to ensure an effective and appropriate health system response during the H1N1 influenza pandemic.

  9. Will the community nurse continue to function during H1N1 influenza pandemic: a cross-sectional study of Hong Kong community nurses?

    Directory of Open Access Journals (Sweden)

    Gao Tiffany T

    2010-04-01

    Full Text Available Abstract Background Healthcare workers have been identified as one of the high risk groups for being infected with influenza during influenza pandemic. Potential levels of absenteeism among healthcare workers in hospital settings are high. However, there was no study to explore the attitudes of healthcare workers in community setting towards the preparedness to the novel H1N1 influenza pandemic. The aim of this study was to explore the willingness of community nurses in Hong Kong to work during H1N1 influenza pandemic. Methods A cross-sectional survey was conducted among all 401 community nurses employed by the Hospital Authority in Hong Kong when the WHO pandemic alert level was 6. Results The response rate of this study was 66.6%. 76.9% participants reported being "not willing" (33.3% or "not sure" (43.6% to take care of patients during H1N1 influenza pandemic. The self-reported reasons for being unwilling to report to duty during H1N1 influenza pandemic were psychological stress (55.0% and fear of being infected H1N1 influenza (29.2%. The reported unwillingness to report to duty was marginally significantly associated with the request for further training of using infection control clinical guideline (OR: 0.057; CI: 0.25-1.02. Those who reported unwillingness or not being sure about taking care of the patients during H1N1 influenza pandemic were more depressed (p Conclusions Interventions to provide infection control training and address community nurses' psychological needs might increase their willingness to provide care to patients in the community during H1N1 influenza pandemic. This would help to ensure an effective and appropriate health system response during the H1N1 influenza pandemic.

  10. Enhanced surveillance of initial cases of pandemic H1N1 2009 influenza in Ireland, April-July 2009.

    LENUS (Irish Health Repository)

    Martin, J

    2009-09-24

    From 28 April to 18 July 2009 there were 156 cases of pandemic H1N1 2009 influenza confirmed in Ireland. During this time, Ireland was in containment phase, and detailed case-based epidemiological information was gathered on all cases presenting in the community and acute health care setting. Active case finding was performed among contacts of cases. Eighty percent of cases were in people less than 35 years of age and 86% were imported. The most frequent symptoms were fever, sore throat, myalgia and dry cough. Nine people were hospitalized, no fatalities occurred.

  11. Lessons from pandemic influenza A(H1N1): the research-based vaccine industry's perspective.

    Science.gov (United States)

    Abelin, Atika; Colegate, Tony; Gardner, Stephen; Hehme, Norbert; Palache, Abraham

    2011-02-01

    As A(H1N1) influenza enters the post-pandemic phase, health authorities around the world are reviewing the response to the pandemic. To ensure this process enhances future preparations, it is essential that perspectives are included from all relevant stakeholders, including vaccine manufacturers. This paper outlines the contribution of R&D-based influenza vaccine producers to the pandemic response, and explores lessons that can be learned to improve future preparedness. The emergence of 2009 A(H1N1) influenza led to unprecedented collaboration between global health authorities, scientists and manufacturers, resulting in the most comprehensive pandemic response ever undertaken, with a number of vaccines approved for use three months after the pandemic declaration. This response was only possible because of the extensive preparations undertaken during the last decade. During this period, manufacturers greatly increased influenza vaccine production capacity, and estimates suggest a further doubling of capacity by 2014. Producers also introduced cell-culture technology, while adjuvant and whole virion technologies significantly reduced pandemic vaccine antigen content. This substantially increased pandemic vaccine production capacity, which in July 2009 WHO estimated reached 4.9 billion doses per annum. Manufacturers also worked with health authorities to establish risk management plans for robust vaccine surveillance during the pandemic. Individual producers pledged significant donations of vaccine doses and tiered-pricing approaches for developing country supply. Based on the pandemic experience, a number of improvements would strengthen future preparedness. Technical improvements to rapidly select optimal vaccine viruses, and processes to speed up vaccine standardization, could accelerate and extend vaccine availability. Establishing vaccine supply agreements beforehand would avoid the need for complex discussions during a period of intense time pressure. Enhancing

  12. Low adherence to influenza vaccination campaigns: is the H1N1 virus pandemic to be blamed?

    Directory of Open Access Journals (Sweden)

    Trivellin Valeria

    2011-11-01

    Full Text Available Abstract Background Over the last few months, debates about the handling of the influenza virus A (H1N1 pandemic took place, in particular regarding the change of the WHO pandemic definition, economic interests, the dramatic communication style of mass media. The activation of plans to reduce the virus diffusion resulted in an important investment of resources. Were those investments proportionate to the risk? Was the pandemic overrated? The workload of the Pediatric Emergency Room (P.E.R. at a teaching hospital in Varese (Northern Italy was investigated in order to evaluate the local diffusion and severity of the new H1N1 influenza epidemic. Discussion A 100% increase of the number of P.E.R. visits, particularly for influenza-like illness, was recorded during weeks 42-46 of 2009 (October, 17 to November, 2; the low rate of hospitalization and the mild presentation of the infection gave rise to the conclusion that the pandemic risk was overrated. Mass media communications concerning the new virus created a disproportionate fear in the population that significantly enhanced the burden of cares at the hospital. In the absence of generally implemented measures for etiological diagnosis, the actual incidence of the H1N1 infection could not be estimated. Virus identification, in fact, was limited to children showing severe symptoms after consultancy with an infectious disease specialist. The alarming nature of the communication campaign and the choice to limit etiologic diagnosis to severe cases created a climate of uncertainty which significantly contributed to the massive admissions to the P.E.R.. Summary The communication strategy adopted by the mass media was an important element during the pandemic: the absence of clarity contributed to the spread of a pandemic phobia that appeared to result more from the sensationalism of the campaign than from infection with the novel influenza A variant of human, avian, swine origin virus. One relevant effect

  13. An Outbreak of 2009 Pandemic Influenza A (H1N1) Virus Infection in an Elementary School in Pennsylvania

    Science.gov (United States)

    Bhattarai, Achuyt; Fagan, Ryan P.; Ostroff, Stephen; Sodha, Samir V.; Moll, Mària E.; Lee, Bruce Y.; Chang, Chung-Chou H.; Ennis, Brent; Britz, Phyllis; Fiore, Anthony; Nguyen, Michael; Palekar, Rakhee; Archer, W. Roodly; Gift, Thomas L.; Leap, Rebecca; Nygren, Benjamin L.; Cauchemez, Simon; Angulo, Frederick J.; Swerdlow, David

    2011-01-01

    In May 2009, one of the earliest outbreaks of 2009 pandemic influenza A virus (pH1N1) infection resulted in the closure of a semi-rural Pennsylvania elementary school. Two sequential telephone surveys were administered to 1345 students (85% of the students enrolled in the school) and household members in 313 households to collect data on influenza-like illness (ILI). A total of 167 persons (12.4%) among those in the surveyed households, including 93 (24.0%) of the School A students, reported ILI. Students were 3.1 times more likely than were other household members to develop ILI (95% confidence interval [CI], 2.3–4.1). Fourth-grade students were more likely to be affected than were students in other grades (relative risk, 2.2; 95% CI, 1.2–3.9). pH1N1 was confirmed in 26 (72.2%) of the individuals tested by real-time reverse-transcriptase polymerase chain reaction. The outbreak did not resume upon the reopening of the school after the 7-day closure. This investigation found that pH1N1 outbreaks at schools can have substantial attack rates; however, grades and classrooms are affected variably. Additioanl study is warranted to determine the effectiveness of school closure during outbreaks. PMID:21342888

  14. Impact of mass media on public behavior and physicians: an ecological study of the H1N1 influenza pandemic.

    Science.gov (United States)

    Codish, Shlomi; Novack, Lena; Dreiher, Jacob; Barski, Leonid; Jotkowitz, Alan; Zeller, Lior; Novack, Victor

    2014-06-01

    The mass media plays an important role in public health behavior. The objective of the present study was to investigate the effect of mass media coverage of the H1N1 pandemic on the number of emergency department (ED) visits and hospital admission rates. An ecological study of ED visits to 8 general Israeli hospitals due to influenza-like illness during the period June-October 2009 was performed. Data on the number of visits per day for children and adults and daily hospitalization rates were analyzed. Associations with the estimated value of H1N1-related publications and weekly reports from nationwide sentinel clinics were assessed. The analysis was performed in 2012-2013. There were 55,070 ED visits due to influenza-like illness during the study period. The overall number of media reports was 1,812 (14.3% radio broadcasts, 9.8% television broadcasts, 27.5% newspaper articles, and 48.5% major website reports). The overall estimated value of advertising of publications was $16,399,000, excluding the Internet. While H1N1 incidence recorded by Israeli sentinel clinics showed no association with mass media publications, peaks of media reports were followed by an increase in the number of ED visits, usually with a delay of 3 days (P = .005). This association was noted in children (P .1), with a corresponding decrease in hospital admission rates. Publications' framing had no association with ED visits. During the 2009 H1N1 influenza outbreak in Israel, an increase in mass media coverage was associated with an increase in pediatric ED visits.

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

    Science.gov (United States)

    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.

  16. Oseltamivir for treatment and prevention of pandemic influenza A/H1N1 virus infection in households, Milwaukee, 2009

    Directory of Open Access Journals (Sweden)

    Miller Joel C

    2010-07-01

    Full Text Available Abstract Background During an influenza pandemic, a substantial proportion of transmission is thought to occur in households. We used data on influenza progression in individuals and their contacts collected by the City of Milwaukee Health Department (MHD to study the transmission of pandemic influenza A/H1N1 virus in 362 households in Milwaukee, WI, and the effects of oseltamivir treatment and chemoprophylaxis. Methods 135 households had chronological information on symptoms and oseltamivir usage for all household members. The effect of oseltamivir treatment and other factors on the household secondary attack rate was estimated using univariate and multivariate logistic regression with households as the unit of analysis. The effect of oseltamivir treatment and other factors on the individual secondary attack rate was estimated using univariate and multivariate logistic regression with individual household contacts as the unit of analysis, and a generalized estimating equations approach was used to fit the model to allow for clustering within households. Results Oseltamivir index treatment on onset day or the following day (early treatment was associated with a 42% reduction (OR: 0.58, 95% CI: 0.19, 1.73 in the odds of one or more secondary infections in a household and a 50% reduction (OR: 0.5, 95% CI: 0.17, 1.46 in the odds of a secondary infection in individual contacts. The confidence bounds are wide due to a small sample of households with early oseltamivir index usage - in 29 such households, 5 had a secondary attack. Younger household contacts were at higher risk of infection (OR: 2.79, 95% CI: 1.50-5.20. Conclusions Early oseltamivir treatment may be beneficial in preventing H1N1pdm influenza transmission; this may have relevance to future control measures for influenza pandemics. Larger randomized trials are needed to confirm this finding statistically.

  17. A duplex real-time RT-PCR assay for detecting H5N1 avian influenza virus and pandemic H1N1 influenza virus

    OpenAIRE

    Kang, Xiao-ping; Jiang, Tao; Li, Yong-qiang; Lin, Fang; Liu, Hong; Chang, Guo-hui; Zhu, Qing-yu; Qin, E-de; Qin, Cheng-feng; Yang, Yin-hui

    2010-01-01

    Abstract A duplex real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay was improved for simultaneous detection of highly pathogenic H5N1 avian influenza virus and pandemic H1N1 (2009) influenza virus, which is suitable for early diagnosis of influenza-like patients and for epidemiological surveillance. The sensitivity of this duplex real-time RT-PCR assay was 0.02 TCID50 (50% tissue culture infective dose) for H5N1 and 0.2 TCID50 for the pandemic H1N1, which was the same a...

  18. Mortality burden of the 2009 A/H1N1 influenza pandemic in France: comparison to seasonal influenza and the A/H3N2 pandemic.

    Directory of Open Access Journals (Sweden)

    Magali Lemaitre

    Full Text Available BACKGROUND: The mortality burden of the 2009 A/H1N1 pandemic remains unclear in many countries due to delays in reporting of death statistics. We estimate the age- and cause-specific excess mortality impact of the pandemic in France, relative to that of other countries and past epidemic and pandemic seasons. METHODS: We applied Serfling and Poisson excess mortality approaches to model weekly age- and cause-specific mortality rates from June 1969 through May 2010 in France. Indicators of influenza activity, time trends, and seasonal terms were included in the models. We also reviewed the literature for country-specific estimates of 2009 pandemic excess mortality rates to characterize geographical differences in the burden of this pandemic. RESULTS: The 2009 A/H1N1 pandemic was associated with 1.0 (95% Confidence Intervals (CI 0.2-1.9 excess respiratory deaths per 100,000 population in France, compared to rates per 100,000 of 44 (95% CI 43-45 for the A/H3N2 pandemic and 2.9 (95% CI 2.3-3.7 for average inter-pandemic seasons. The 2009 A/H1N1 pandemic had a 10.6-fold higher impact than inter-pandemic seasons in people aged 5-24 years and 3.8-fold lower impact among people over 65 years. CONCLUSIONS: The 2009 pandemic in France had low mortality impact in most age groups, relative to past influenza seasons, except in school-age children and young adults. The historical A/H3N2 pandemic was associated with much larger mortality impact than the 2009 pandemic, across all age groups and outcomes. Our 2009 pandemic excess mortality estimates for France fall within the range of previous estimates for high-income regions. Based on the analysis of several mortality outcomes and comparison with laboratory-confirmed 2009/H1N1 deaths, we conclude that cardio-respiratory and all-cause mortality lack precision to accurately measure the impact of this pandemic in high-income settings and that use of more specific mortality outcomes is important to obtain reliable

  19. Oseltamivir compounding in the hospital pharmacy during the (H1N1 influenza pandemic

    Directory of Open Access Journals (Sweden)

    Márcia Lúcia de Mário Marin

    2010-01-01

    Full Text Available AIMS: Pandemics impose large demands on the health care system. The supply of appropriate chemotherapeutic agents, namely oseltamivir solution, presented a serious challenge in the recent influenza pandemic. This study reports on the rational series of pharmacotechnical steps that were followed to appropriately handle bulk oseltamivir powder to meet the increased demand. METHODS: During a six-week period in August and September of 2009, a task force was created in the Central Pharmacy of Hospital das Clínicas to convert imported oseltamivir phosphate into ready-to-use solution for utilization by physicians and public health authorities. The protocol included dissolution, physico-chemical tests and the bottling of a liquid microdose formulation for emergency room and outpatient dispensing with adequate quality control during all phases. RESULTS: The successful production routine was based on a specially designed flowchart according to which a batch of 33210 g of oseltamivir powder was converted into 32175 solution units during the aforementioned period with a net loss of only 2.6%. The end products were bottles containing 50 ml of 15 mg/mL oseltamivir solution. The measured concentration was stable and accurate (97.5% - 102.0% of the nominal value. The drug was prescribed as both a prophylactic and therapeutic agent. DISCUSSION: Hospital pharmacies are conventionally engaged in the manipulation of medical prescriptions and specialty drugs. They are generally responsible for only small-scale equipment used for manufacturing and quality-control procedures. The compounding of oseltamivir was a unique effort dictated by exceptional circumstances. CONCLUSION: The shortage of oseltamivir solution for clinical use was solved by emergency operationalization of a semi-industrial process in which bulk powder was converted into practical vials for prompt delivery.

  20. Evidence of cross-reactive immunity to 2009 pandemic influenza A virus in workers seropositive to swine H1N1 influenza viruses circulating in Italy.

    Directory of Open Access Journals (Sweden)

    Maria A De Marco

    Full Text Available BACKGROUND: Pigs play a key epidemiologic role in the ecology of influenza A viruses (IAVs emerging from animal hosts and transmitted to humans. Between 2008 and 2010, we investigated the health risk of occupational exposure to swine influenza viruses (SIVs in Italy, during the emergence and spread of the 2009 H1N1 pandemic (H1N1pdm virus. METHODOLOGY/PRINCIPAL FINDINGS: Serum samples from 123 swine workers (SWs and 379 control subjects (Cs, not exposed to pig herds, were tested by haemagglutination inhibition (HI assay against selected SIVs belonging to H1N1 (swH1N1, H1N2 (swH1N2 and H3N2 (swH3N2 subtypes circulating in the study area. Potential cross-reactivity between swine and human IAVs was evaluated by testing sera against recent, pandemic and seasonal, human influenza viruses (H1N1 and H3N2 antigenic subtypes. Samples tested against swH1N1 and H1N1pdm viruses were categorized into sera collected before (n. 84 SWs; n. 234 Cs and after (n. 39 SWs; n. 145 Cs the pandemic peak. HI-antibody titers ≥10 were considered positive. In both pre-pandemic and post-pandemic peak subperiods, SWs showed significantly higher swH1N1 seroprevalences when compared with Cs (52.4% vs. 4.7% and 59% vs. 9.7%, respectively. Comparable HI results were obtained against H1N1pdm antigen (58.3% vs. 7.7% and 59% vs. 31.7%, respectively. No differences were found between HI seroreactivity detected in SWs and Cs against swH1N2 (33.3% vs. 40.4% and swH3N2 (51.2 vs. 55.4% viruses. These findings indicate the occurrence of swH1N1 transmission from pigs to Italian SWs. CONCLUSION/SIGNIFICANCE: A significant increase of H1N1pdm seroprevalences occurred in the post-pandemic peak subperiod in the Cs (p<0.001 whereas SWs showed no differences between the two subperiods, suggesting a possible occurrence of cross-protective immunity related to previous swH1N1 infections. These data underline the importance of risk assessment and occupational health surveillance activities aimed

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

    Science.gov (United States)

    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.

  2. Surveillance of hospitalizations with pandemic A(H1N1 2009 influenza infection in Queensland, Australia

    Directory of Open Access Journals (Sweden)

    Frances Birrell

    2011-05-01

    Full Text Available Objective : To describe the demographic and clinical characteristics of patients hospitalized with pandemic A(H1N1 2009 infection in Queensland, Australia between 25 May and 3 October 2009 and to examine the relationship between timing of antiviral treatment and severity of illness.Method: Using data from the Queensland Health EpiLog information system, descriptive analysis and logistic regression modelling were used to describe and model factors which influence patient outcomes (death, admission to intensive care unit and/or special care unit. Data on patients admitted to hospital in Queensland with confirmed pandemic A(H1N1 2009 infection were included in this analysis.Results: 1236 patients with pandemic A(H1N1 2009 infection were admitted to hospitals in Queensland during the study period. Of the total group: 15% were admitted to an intensive care unit or special care unit; 3% died; 34% were under the age of 18 years and 8% were 65 years of age or older; and 55% had at least one underlying medical condition. Among the 842 patients for whom data were available regarding the use of antiviral drugs, antiviral treatment was initiated in 737 (87.5% patients with treatment commencing at a median of one day (range 1–33 days after onset of illness. Admission to an intensive care unit or special care unit (ICU/SCU or death was significantly associated with increased age, lack of timeliness of antiviral treatment, chronic renal disease and morbid obesity.Discussion: Early antiviral treatment was significantly associated with lower likelihood of ICU/SCU admission or death. Early antiviral treatment for influenza cases may therefore have important public health implications.

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

    Science.gov (United States)

    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.

  4. Genetic divergence of influenza A NS1 gene in pandemic 2009 H1N1 isolates with respect to H1N1 and H3N2 isolates from previous seasonal epidemics

    Directory of Open Access Journals (Sweden)

    Campanini Giulia

    2010-09-01

    Full Text Available Abstract Background The Influenza A pandemic sustained by a new H1N1 variant (H1N1v started in Mexico and the USA at the end of April 2009 spreading worldwide in a few weeks. In this study we investigate the variability of the NS1 gene of the pandemic H1N1v strain with respect to previous seasonal strains circulating in humans and the potential selection of virus variants through isolation in cell culture. Methods During the period April 27th 2009-Jan 15th 2010, 1633 potential 2009 H1N1v cases have been screened at our center using the CDC detection and typing realtime RT-PCR assays. Virus isolation on MDCK cells was systematically performed in 1/10 positive cases. A subset of 51 H1N1v strains isolated in the period May-September 2009 was selected for NS1 gene sequencing. In addition, 15 H1N1 and 47 H3N2 virus isolates from three previous seasonal epidemics (2006-2009 were analyzed in parallel. Results A low variability in the NS1 amino acid (aa sequence among H1N1v isolates was shown (aa identity 99.5%. A slightly higher NS1 variability was observed among H1N1 and H3N2 strains from previous epidemics (aa identity 98.6% and 98.9%, respectively. The H1N1v strains were closely related (aa identity 92.1% to swine reference strain (A/swine/Oklahoma/042169/2008. In contrast, substantial divergence (aa identity 83.4% with respect to human reference strain A/Brevig Mission/1/1918 and previous epidemic strains H1N1 and H3N2 (aa identity 78.9% and 77.6%, respectively was shown. Specific sequence signatures of uncertain significance in the new virus variant were a C-terminus deletion and a T215P substitution. Conclusions The H1N1v NS1 gene was more conserved than that of previous epidemic strains. In addition, a closer genetic identity of H1N1v with the swine than the human reference strains was shown. Hot-spots were shown in the H1N1v NS1 aa sequence whose biologic relevance remains to be investigated.

  5. [Pandemic influenza A (H1N1 virus) on Futuna Island in the Pacific, from August to September 2009].

    Science.gov (United States)

    Chenaitia, Hichem; Massa, Horace; Garry, Philippe; Puget, André; Yvon, Jean-Francois; Dutaut, Elisabeth; Bessereau, Jacques; Michelet, Pierre; Auffray, Jean-Pierre; Delmont, Jean

    2011-03-01

    The aim of this study is to report the observation of the pandemic of influenza A (H1N1 virus) from August to September 2009 on the island of Futuna, in a context of isolated island that may mimic an environment closed. We conducted a prospective observational study of influenza-like illness, from the first confirmed case of influenza A on the island until the end of the epidemic wave. From August 15 to September 20, 2009, 1536 cases of influenza syndrome were identified. The estimate of the overall clinical attack rate was 36 %. The evolution of the epidemic shows an explosion of new cases of influenza A and subsequently a rapid decline of the epidemic. The spread of the infection was made by contiguity, jumping from one city to another. The cumulative number of cases by age group shows that the majority of cases were children and young adults under the age of 20 years. The most frequent symptoms were cough, rhinorrhea, headache, myalgia or asthenia, and fever. This study, despite these limitations, shows an explosive epidemic of influenza A, which can be explained by the circulation of virus that has been fostered by gatherings of public and closed environment. Age group classification shows that majority of cases were young, in contrast to seasonal influenza, but the symptoms were alike. This study highlights the difficulties to manage an epidemic surveillance system at high level and given the quick spread of the disease. Copyright © 2010. Published by Elsevier Masson SAS.

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

    Science.gov (United States)

    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

  7. Influenza A (H1N1-2009) pandemic in Singapore--public health control measures implemented and lessons learnt.

    Science.gov (United States)

    Tay, Joanne; Ng, Yeuk Fan; Cutter, Jeffery L; James, Lyn

    2010-04-01

    We describe the public health control measures implemented in Singapore to limit the spread of influenza A (H1N1-2009) and mitigate its social effects. We also discuss the key learning points from this experience. Singapore's public health control measures were broadly divided into 2 phases: containment and mitigation. Containment strategies included the triage of febrile patients at frontline healthcare settings, admission and isolation of confirmed cases, mandatory Quarantine Orders (QO) for close contacts, and temperature screening at border entry points. After sustained community transmission became established, containment shifted to mitigation. Hospitals only admitted H1N1-2009 cases based on clinical indications, not for isolation. Mild cases were managed in the community. Contact tracing and QOs tapered off, and border temperature screening ended. The 5 key lessons learnt were: (1) Be prepared, but retain flexibility in implementing control measures; (2) Surveillance, good scientific information and operational research can increase a system's ability to manage risk during a public health crisis; (3) Integrated systems-level responses are essential for a coherent public health response; (4) Effective handling of manpower surges requires creative strategies; and (5) Communication must be strategic, timely, concise and clear. Singapore's effective response to the H1N1-2009 pandemic, founded on experience in managing the 2003 SARS epidemic, was a whole-of-government approach towards pandemic preparedness planning. Documenting the measures taken and lessons learnt provides a learning opportunity for both doctors and policy makers, and can help fortify Singapore's ability to respond to future major disease outbreaks.

  8. Risk factors and immunity in a nationally representative population following the 2009 influenza A(H1N1 pandemic.

    Directory of Open Access Journals (Sweden)

    Don Bandaranayake

    Full Text Available BACKGROUND: Understanding immunity, incidence and risk factors of the 2009 influenza A(H1N1 pandemic (2009 H1N1 through a national seroprevalence study is necessary for informing public health interventions and disease modelling. METHODS AND FINDINGS: We collected 1687 serum samples and individual risk factor data between November-2009 to March-2010, three months after the end of the 2009 H1N1 wave in New Zealand. Participants were randomly sampled from selected general practices countrywide and hospitals in the Auckland region. Baseline immunity was measured from 521 sera collected during 2004 to April-2009. Haemagglutination inhibition (HI antibody titres of ≥1:40 against 2009 H1N1 were considered seroprotective as well as seropositive. The overall community seroprevalence was 26.7% (CI:22.6-29.4. The seroprevalence varied across age and ethnicity. Children aged 5-19 years had the highest seroprevalence (46.7%;CI:38.3-55.0, a significant increase from the baseline (14%;CI:7.2-20.8. Older adults aged ≥60 had no significant difference in seroprevalence between the serosurvey (24.8%;CI:18.7-30.9 and baseline (22.6%;CI:15.3-30.0. Pacific peoples had the highest seroprevalence (49.5%;CI:35.1-64.0. There was no significant difference in seroprevalence between both primary (29.6%;CI:22.6-36.5 and secondary healthcare workers (25.3%;CI:20.8-29.8 and community participants. No significant regional variation was observed. Multivariate analysis indicated age as the most important risk factor followed by ethnicity. Previous seasonal influenza vaccination was associated with higher HI titres. Approximately 45.2% of seropositive individuals reported no symptoms. CONCLUSIONS: Based on age and ethnicity standardisation to the New Zealand Population, about 29.5% of New Zealanders had antibody titers at a level consistent with immunity to 2009 H1N1. Around 18.3% of New Zealanders were infected with the virus during the first wave including about one child

  9. [Assessment of the MF59-adjuvanted pandemic influenza A/H1N1 vaccine. Systematic review of literature].

    Science.gov (United States)

    Ruiz-Aragón, J; Grande Tejada, A M; Márquez-Peláez, S; Molina Linde, J M; Yang, R

    2013-10-01

    To assess the efficacy and safety of MF59-adjuvanted pandemic influenza A/H1N1 vaccine in children. A systematic review of the literature was performed after searching the MedLine and Embase electronic databases, and manual search in specialties journals, with MeSH terms and and free terms. Inclusion criteria were clinical trials with children vaccinated with MF59-adjuvanted influenza A/H1N1 vaccine, compared with other vaccines doses with/without MF59-adjuvanted. The immunogenicity and safety of the vaccine was recorded. The quality of the studies included was assessed by CASPe checklist. Four clinical trials with moderate quality were selected. The local and systemic adverse effects were rare and mild, with no differences between groups. Seroconversion and seroprotection levels were higher with MF59-adjuvanted vaccines. Antibody titres were also higher with the adjuvant vaccines. The adjuvant vaccine has a good efficacy and safety profile. The adverse effects that may occur are common and appear similarly in both vaccination groups. Copyright © 2012 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  10. Mutations in polymerase genes enhanced the virulence of 2009 pandemic H1N1 influenza virus in mice.

    Directory of Open Access Journals (Sweden)

    Wenfei Zhu

    Full Text Available Influenza A virus can infect a wide variety of animal species with illness ranging from mild to severe, and is a continual cause for concern. Genetic mutations that occur either naturally or during viral adaptation in a poorly susceptible host are key mechanisms underlying the evolution and virulence of influenza A virus. Here, the variants containing PA-A36T or PB2-H357N observed in the mouse-adapted descendants of 2009 pandemic H1N1 virus (pH1N1, A/Sichuan/1/2009 (SC, were characterized. Both mutations enhanced polymerase activity in mammalian cells. These effects were confirmed using recombinant SC virus containing polymerase genes with wild type (WT or mutant PA or PB2. The PA-A36T mutant showed enhanced growth property compared to the WT in both human A549 cells and porcine PK15 cells in vitro, without significant effect on viral propagation in murine LA-4 cells and pathogenicity in mice; however, it did enhance the lung virus titer. PB2-H357N variant demonstrated growth ability comparable to the WT in A549 cells, but replicated well in PK15, LA-4 cells and in mice with an enhanced pathogenic phenotype. Despite such mutations are rare in nature, they could be observed in avian H5 and H7 subtype viruses which were currently recognized to pose potential threat to human. Our findings indicated that pH1N1 may adapt well in mammals when acquiring these mutations. Therefore, future molecular epidemiological surveillance should include scrutiny of both markers because of their potential impact on pathogenesis.

  11. Determinants of non-vaccination against pandemic 2009 H1N1 influenza in pregnant women: a prospective cohort study.

    Directory of Open Access Journals (Sweden)

    Romain Freund

    Full Text Available BACKGROUND: In October 2009, the French government organized a national-wide, free of charge vaccination campaign against pandemic H1N1 influenza virus, especially targeting pregnant women, a high risk group for severe illness. The study objective was to evaluate pandemic flu vaccine uptake and factors associated with non-vaccination in a population of pregnant women. METHODOLOGY/PRINCIPAL FINDINGS: In a prospective cohort conducted in 3 maternity hospitals in Paris, 882 pregnant women were randomly included between October 12, 2009 and February 3, 2010, with the aim to study characteristics of pandemic influenza during pregnancy. At inclusion, socio-demographic, medical, obstetrical factors and those associated with a higher risk of flu exposition and disease-spreading were systematically collected. Pandemic flu vaccine uptake was checked until delivery. 555 (62.9% women did not get vaccinated. Determinants associated with non-vaccination in a multivariate logistic regression were: geographic origin (Sub-Saharan African origin, adjusted Odd Ratio aOR = 5.4[2.3-12.7], North African origin, aOR = 2.5[1.3-4.7] and Asian origin, aOR = 2.1[1.7-2.6] compared to French and European origin and socio-professional categories (farmers, craftsmen and tradesmen, aOR = 2.3[2.0-2.6], intermediate professionals, aOR = 1.3[1.0-1.6], employees and manual workers, aOR = 2.5[1.4-4.4] compared to managers and intellectual professionals. The probability of not receiving pandemic flu vaccine was lower among women vaccinated against seasonal flu in the previous 5 years (aOR = 0.6[0.4-0.8] and among those who stopped smoking before or early during pregnancy (aOR = 0.6[0.4-0.8]. Number of children less than 18 years old living at home, work in contact with children or in healthcare area, or professional contact with the public, were not associated with a higher vaccine uptake. CONCLUSIONS/SIGNIFICANCE: In this cohort of pregnant women, vaccine coverage against pandemic

  12. The 2009 A(H1N1) influenza pandemic in the French Armed Forces: epidemiological surveillance and operational management.

    Science.gov (United States)

    Pohl, Jean-Baptiste; Mayet, Aurélie; Bédubourg, Gabriel; Duron, Sandrine; Michel, Rémy; Deparis, Xavier; Rapp, Christophe; Godart, Patrick; Migliani, René; Meynard, Jean-Baptiste

    2014-02-01

    The main objective of this study was to evaluate the contribution of a newly implemented daily surveillance system to the management of the 2009 A(H1N1) influenza pandemic by the military decision-makers at different levels in the French Department of Defence. The study sample included all medical advisors in the Ministry of Defence and the French Armed Forces Staff and also the members of the specific committee dedicated to flu pandemic control. The variables studied were mental representation of epidemiology, relevance, usefulness, and real-time use of surveillance data using quantitative questionnaires and qualitative face-to-face semistructured interviews. Among the risk managers of the flu pandemic in the Armed Forces, 84% responded. The data generated by epidemiological surveillance were considered relevant and useful, and were reported as effectively used. On the basis of the information produced, concrete actions were planned and implemented in the French Armed Forces. In a pandemic situation involving low mortality, the daily monitoring of the disease did not target public health issues, but it was mainly used to assess the availability of the Armed Forces in real time. For the military staff, epidemiological surveillance represents an essential information tool for the conduct of operations. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

  13. Incidence and Epidemiology of Hospitalized Influenza Cases in Rural Thailand during the Influenza A (H1N1)pdm09 Pandemic, 2009–2010

    Science.gov (United States)

    Baggett, Henry C.; Chittaganpitch, Malinee; Thamthitiwat, Somsak; Prapasiri, Prabda; Naorat, Sathapana; Sawatwong, Pongpun; Ditsungnoen, Darunee; Olsen, Sonja J.; Simmerman, James M.; Srisaengchai, Prasong; Chantra, Somrak; Peruski, Leonard F.; Sawanpanyalert, Pathom; Maloney, Susan A.; Akarasewi, Pasakorn

    2012-01-01

    Background Data on the burden of the 2009 influenza pandemic in Asia are limited. Influenza A(H1N1)pdm09 was first reported in Thailand in May 2009. We assessed incidence and epidemiology of influenza-associated hospitalizations during 2009–2010. Methods We conducted active, population-based surveillance for hospitalized cases of acute lower respiratory infection (ALRI) in all 20 hospitals in two rural provinces. ALRI patients were sampled 1∶2 for participation in an etiology study in which nasopharyngeal swabs were collected for influenza virus testing by PCR. Results Of 7,207 patients tested, 902 (12.5%) were influenza-positive, including 190 (7.8%) of 2,436 children aged incidence of hospitalized influenza cases was 136 per 100,000, highest in ages 75 years (407 per 100,000). The incidence of influenza A(H1N1)pdm09 was 62 per 100,000 (214 per 100,000 in children <5 years). Eleven influenza-infected patients required mechanical ventilation, and four patients died, all adults with influenza A(H1N1)pdm09 (1) or H3N2 (3). Conclusions Influenza-associated hospitalization rates in Thailand during 2009–10 were substantial and exceeded rates described in western countries. Influenza A(H1N1)pdm09 predominated, but H3N2 also caused notable morbidity. Expanded influenza vaccination coverage could have considerable public health impact, especially in young children. PMID:23139802

  14. Vaccination against pandemic influenza A/H1N1v in England: a real-time economic evaluation.

    Science.gov (United States)

    Baguelin, Marc; Hoek, Albert Jan Van; Jit, Mark; Flasche, Stefan; White, Peter J; Edmunds, W John

    2010-03-11

    Decisions on how to mitigate an evolving pandemic are technically challenging. We present a real-time assessment of the effectiveness and cost-effectiveness of alternative influenza A/H1N1v vaccination strategies. A transmission dynamic model was fitted to the estimated number of cases in real-time, and used to generate plausible autumn scenarios under different vaccination options. The proportion of these cases by age and risk group leading to primary care consultations, National Pandemic Flu Service consultations, emergency attendances, hospitalisations, intensive care and death was then estimated using existing data from the pandemic. The real-time model suggests that the epidemic will peak in early November, with the peak height being similar in magnitude to the summer wave. Vaccination of the high-risk groups is estimated to prevent about 45 deaths (80% credibility interval 26-67), and save around 2900 QALYs (80% credibility interval 1600-4500). Such a programme is very likely to be cost-effective if the cost of vaccine purchase itself is treated as a sunk cost. Extending vaccination to low-risk individuals is expected to result in more modest gains in deaths and QALYs averted. Extending vaccination to school-age children would be the most cost-effective extension. The early availability of vaccines is crucial in determining the impact of such extensions. There have been a considerable number of cases of H1N1v in England, and so the benefits of vaccination to mitigate the ongoing autumn wave are limited. However, certain groups appear to be at significantly higher risk of complications and deaths, and so it appears both effective and cost-effective to vaccinate them. The United Kingdom was the first country to have a major epidemic in Europe. In countries where the epidemic is not so far advanced vaccination of children may be cost-effective. Similar, detailed, real-time modelling and economic studies could help to clarify the situation.

  15. H1N1 influenza (Swine flu)

    Science.gov (United States)

    Swine flu; H1N1 type A influenza ... The H1N1 virus is now considered a regular flu virus. It is one of the three viruses included in the regular (seasonal) flu vaccine . You cannot get H1N1 flu virus from ...

  16. Impact of antiviral treatment and hospital admission delay on risk of death associated with 2009 A/H1N1 pandemic influenza in Mexico

    Directory of Open Access Journals (Sweden)

    Chowell Gerardo

    2012-04-01

    Full Text Available Abstract Background Increasing our understanding of the factors affecting the severity of the 2009 A/H1N1 influenza pandemic in different regions of the world could lead to improved clinical practice and mitigation strategies for future influenza pandemics. Even though a number of studies have shed light into the risk factors associated with severe outcomes of 2009 A/H1N1 influenza infections in different populations (e.g., [1-5], analyses of the determinants of mortality risk spanning multiple pandemic waves and geographic regions are scarce. Between-country differences in the mortality burden of the 2009 pandemic could be linked to differences in influenza case management, underlying population health, or intrinsic differences in disease transmission [6]. Additional studies elucidating the determinants of disease severity globally are warranted to guide prevention efforts in future influenza pandemics. In Mexico, the 2009 A/H1N1 influenza pandemic was characterized by a three-wave pattern occurring in the spring, summer, and fall of 2009 with substantial geographical heterogeneity [7]. A recent study suggests that Mexico experienced high excess mortality burden during the 2009 A/H1N1 influenza pandemic relative to other countries [6]. However, an assessment of potential factors that contributed to the relatively high pandemic death toll in Mexico are lacking. Here, we fill this gap by analyzing a large series of laboratory-confirmed A/H1N1 influenza cases, hospitalizations, and deaths monitored by the Mexican Social Security medical system during April 1 through December 31, 2009 in Mexico. In particular, we quantify the association between disease severity, hospital admission delays, and neuraminidase inhibitor use by demographic characteristics, pandemic wave, and geographic regions of Mexico. Methods We analyzed a large series of laboratory-confirmed pandemic A/H1N1 influenza cases from a prospective surveillance system maintained by the

  17. Early Detection of Pandemic (H1N1) 2009, Bangladesh

    Science.gov (United States)

    Rahman, Mustafizur; Al Mamun, Abdullah; Haider, Mohammad Sabbir; Zaman, Rashid Uz; Karmakar, Polash Chandra; Nasreen, Sharifa; Muneer, Syeda Mah-E; Homaira, Nusrat; Goswami, Doli Rani; Ahmed, Be-Nazir; Husain, Mohammad Mushtuq; Jamil, Khondokar Mahbuba; Khatun, Selina; Ahmed, Mujaddeed; Chakraborty, Apurba; Fry, Alicia; Widdowson, Marc-Alain; Bresee, Joseph; Azim, Tasnim; Alamgir, A.S.M.; Brooks, Abdullah; Hossain, Mohamed Jahangir; Klimov, Alexander; Rahman, Mahmudur; Luby, Stephen P.

    2012-01-01

    To explore Bangladesh’s ability to detect novel influenza, we examined a series of laboratory-confirmed pandemic (H1N1) 2009 cases. During June–July 2009, event-based surveillance identified 30 case-patients (57% travelers); starting July 29, sentinel sites identified 252 case-patients (1% travelers). Surveillance facilitated response weeks before the spread of pandemic (H1N1) 2009 infection to the general population. PMID:22257637

  18. University life and pandemic influenza: Attitudes and intended behaviour of staff and students towards pandemic (H1N1 2009

    Directory of Open Access Journals (Sweden)

    MacIntyre C Raina

    2010-03-01

    Full Text Available Abstract Background In a pandemic young adults are more likely to be infected, increasing the potential for Universities to be explosive disease outbreak centres. Outbreak management is essential to reduce the impact in both the institution and the surrounding community. Through the use of an online survey, we aimed to measure the perceptions and responses of staff and students towards pandemic (H1N1 2009 at a major university in Sydney, Australia. Methods The survey was available online from 29 June to 30 September 2009. The sample included academic staff, general staff and students of the University. Results A total of 2882 surveys were completed. Nearly all respondents (99.6%, 2870/2882 were aware of the Australian pandemic situation and 64.2% (1851/2882 reported either "no anxiety" or "disinterest." Asian-born respondents were significantly (p Conclusions Responses to a pandemic are subject to change in its pre-, early and mid-outbreak stages. Lessons for these institutions in preparation for a second wave and future disease outbreaks include the need to promote positive public health behaviours amongst young people and students.

  19. Reconstruction of epidemic curves for pandemic influenza A (H1N1 2009 at city and sub-city levels

    Directory of Open Access Journals (Sweden)

    Wong Ngai Sze

    2010-11-01

    Full Text Available Abstract To better describe the epidemiology of influenza at local level, the time course of pandemic influenza A (H1N1 2009 in the city of Hong Kong was reconstructed from notification data after decomposition procedure and time series analysis. GIS (geographic information system methodology was incorporated for assessing spatial variation. Between May and September 2009, a total of 24415 cases were successfully geocoded, out of 25473 (95.8% reports in the original dataset. The reconstructed epidemic curve was characterized by a small initial peak, a nadir followed by rapid rise to the ultimate plateau. The full course of the epidemic had lasted for about 6 months. Despite the small geographic area of only 1000 Km2, distinctive spatial variation was observed in the configuration of the curves across 6 geographic regions. With the relatively uniform physical and climatic environment within Hong Kong, the temporo-spatial variability of influenza spread could only be explained by the heterogeneous population structure and mobility patterns. Our study illustrated how an epidemic curve could be reconstructed using regularly collected surveillance data, which would be useful in informing intervention at local levels.

  20. Estimation of the reproductive number and the serial interval in early phase of the 2009 influenza A/H1N1 pandemic in the USA

    NARCIS (Netherlands)

    White, Laura Forsberg; Wallinga, Jacco; Finelli, Lyn; Reed, Carrie; Riley, Steven; Lipsitch, Marc; Pagano, Marcello

    2009-01-01

    Background The United States was the second country to have a major outbreak of novel influenza A/H1N1 in what has become a new pandemic. Appropriate public health responses to this pandemic depend in part on early estimates of key epidemiological parameters of the virus in defined populations.

  1. Analysis of the effectiveness of interventions used during the 2009 A/H1N1 influenza pandemic

    Directory of Open Access Journals (Sweden)

    Milne George J

    2010-03-01

    Full Text Available Abstract Background Following the emergence of the A/H1N1 2009 influenza pandemic, public health interventions were activated to lessen its potential impact. Computer modelling and simulation can be used to determine the potential effectiveness of the social distancing and antiviral drug therapy interventions that were used at the early stages of the pandemic, providing guidance to public health policy makers as to intervention strategies in future pandemics involving a highly pathogenic influenza strain. Methods An individual-based model of a real community with a population of approximately 30,000 was used to determine the impact of alternative interventions strategies, including those used in the initial stages of the 2009 pandemic. Different interventions, namely school closure and antiviral strategies, were simulated in isolation and in combination to form different plausible scenarios. We simulated epidemics with reproduction numbers R0of 1.5, which aligns with estimates in the range 1.4-1.6 determined from the initial outbreak in Mexico. Results School closure of 1 week was determined to have minimal effect on reducing overall illness attack rate. Antiviral drug treatment of 50% of symptomatic cases reduced the attack rate by 6.5%, from an unmitigated rate of 32.5% to 26%. Treatment of diagnosed individuals combined with additional household prophylaxis reduced the final attack rate to 19%. Further extension of prophylaxis to close contacts (in schools and workplaces further reduced the overall attack rate to 13% and reduced the peak daily illness rate from 120 to 22 per 10,000 individuals. We determined the size of antiviral stockpile required; the ratio of the required number of antiviral courses to population was 13% for the treatment-only strategy, 25% for treatment and household prophylaxis and 40% for treatment, household and extended prophylaxis. Additional simulations suggest that coupling school closure with the antiviral

  2. Will the community nurse continue to function during H1N1 influenza pandemic: a cross-sectional study of Hong Kong community nurses?

    OpenAIRE

    Wong, Eliza LY; Wong, Samuel YS; Kung, Kenny; Cheung, Annie WL; Gao, Tiffany T; Griffiths, Sian

    2010-01-01

    Abstract Background Healthcare workers have been identified as one of the high risk groups for being infected with influenza during influenza pandemic. Potential levels of absenteeism among healthcare workers in hospital settings are high. However, there was no study to explore the attitudes of healthcare workers in community setting towards the preparedness to the novel H1N1 influenza pandemic. The aim of this study was to explore the willingness of community nurses in Hong Kong to work duri...

  3. Protection of human influenza vaccines against a reassortant swine influenza virus of pandemic H1N1 origin using a pig model.

    Science.gov (United States)

    Arunorat, Jirapat; Charoenvisal, Nataya; Woonwong, Yonlayong; Kedkovid, Roongtham; Jittimanee, Supattra; Sitthicharoenchai, Panchan; Kesdangsakonwut, Sawang; Poolperm, Pariwat; Thanawongnuwech, Roongroje

    2017-10-01

    Since the pandemic H1N1 emergence in 2009 (pdmH1N1), many reassortant pdmH1N1 viruses emerged and found circulating in the pig population worldwide. Currently, commercial human subunit vaccines are used commonly to prevent the influenza symptom based on the WHO recommendation. In case of current reassortant swine influenza viruses transmitting from pigs to humans, the efficacy of current human influenza vaccines is of interest. In this study, influenza A negative pigs were vaccinated with selected commercial human subunit vaccines and challenged with rH3N2. All sera were tested with both HI and SN assays using four representative viruses from the surveillance data in 2012 (enH1N1, pdmH1N1, rH1N2 and rH3N2). The results showed no significant differences in clinical signs and macroscopic and microscopic findings among groups. However, all pig sera from vaccinated groups had protective HI titers to the enH1N1, pdmH1N1 and rH1N2 at 21DPV onward and had protective SN titers only to pdmH1N1and rH1N2 at 21DPV onward. SN test results appeared more specific than those of HI tests. All tested sera had no cross-reactivity against the rH3N2. Both studied human subunit vaccines failed to protect and to stop viral shedding with no evidence of serological reaction against rH3N2. SIV surveillance is essential for monitoring a novel SIV emergence potentially for zoonosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Response to the 2009-H1N1 influenza pandemic in the Mekong Basin: surveys of country health leaders

    Directory of Open Access Journals (Sweden)

    Dausey David J

    2011-09-01

    Full Text Available Abstract Background Soon after the 2009-H1N1 virus emerged as the first influenza pandemic in 41 years, countries had an early opportunity to test their preparedness plans, protocols and procedures, including their cooperation with other countries in responding to the global pandemic threat. The Mekong Basin Disease Surveillance cooperation (MBDS comprises six countries - Cambodia, China (Yunnan and Guangxi Provinces, Lao People's Democratic Republic, Myanmar, Thailand and Vietnam - that formally organized themselves in 2001 to cooperate in disease surveillance and control. The pandemic presented an opportunity to assess their responses in light of their individual and joint planning. We conducted two surveys of the MBDS leadership from each country, early during the pandemic and shortly after it ended. Results On average, participants rated their country's pandemic response performance as good in both 2009 and 2010. Post-pandemic (2010, perceived performance quality was best for facility-based interventions (overall mean of 4.2 on a scale from 1 = poor to 5 = excellent, followed by surveillance and information sharing (4.1, risk communications (3.9 and disease prevention and control in communities (3.7. Performance was consistently rated as good or excellent for use of hotlines for case reporting (2010 mean of 4.4 and of selected facility-based interventions (each with a 2010 mean of 4.4: using hospital admission criteria, preparing or using isolation areas, using PPE for healthcare workers and using antiviral drugs for treatment. In at least half the countries, the post-pandemic ratings were lower than initial 2009 assessments for performance related to surveillance, facility-based interventions and risk communications. Conclusions MBDS health leaders perceived their pandemic responses effective in areas previously considered problematic. Most felt that MBDS cooperation helped drive and thus added value to their efforts. Surveillance capacity

  5. A highly pathogenic avian influenza virus H5N1 with 2009 pandemic H1N1 internal genes demonstrated increased replication and transmission in pigs

    Science.gov (United States)

    This study investigated the pathogenicity and transmissibility of a reverse-genetics derived highly pathogenic avian influenza (HPAI) H5N1 influenza A virus (IAV), A/Iraq/775/06, and a reassortant virus comprised of the HA and NA from A/Iraq/775/06 and the internal genes of a 2009 pandemic H1N1, A/N...

  6. A polyvalent influenza A DNA vaccine induces heterologous immunity and protects pigs against pandemic A(H1N1)pdm09 virus infection

    DEFF Research Database (Denmark)

    Bragstad, Karoline; Vinner, Lasse; Hansen, Mette Sif

    2013-01-01

    seasonal and emerging influenza viruses. We have developed an alternative influenza vaccine based on DNA expressing selected influenza proteins of pandemic and seasonal origin. In the current study, we investigated the protection of a polyvalent influenza DNA vaccine approach in pigs. We immunised pigs...... intradermally with a combination of influenza DNA vaccine components based on the pandemic 1918 H1N1 (M and NP genes), pandemic 2009 H1N1pdm09 (HA and NA genes) and seasonal 2005 H3N2 genes (HA and NA genes) and investigated the protection against infection with virus both homologous and heterologous to the DNA...... of this DNA vaccine to limit virus shedding may have an impact on virus spread among pigs which could possibly extend to humans as well, thereby diminishing the risk for epidemics and pandemics to evolve....

  7. In situ molecular identification of the Influenza A (H1N1 2009 Neuraminidase in patients with severe and fatal infections during a pandemic in Mexico City

    Directory of Open Access Journals (Sweden)

    Ocadiz-Delgado Rodolfo

    2013-01-01

    Full Text Available Abstract Background In April 2009, public health surveillance detected an increased number of influenza-like illnesses in Mexico City’s hospitals. The etiological agent was subsequently determined to be a spread of a worldwide novel influenza A (H1N1 triple reassortant. The purpose of the present study was to demonstrate that molecular detection of pandemic influenza A (H1N1 2009 strains is possible in archival material such as paraffin-embedded lung samples. Methods In order to detect A (H1N1 virus sequences in archived biological samples, eight paraffin-embedded lung samples from patients who died of pneumonia and respiratory failure were tested for influenza A (H1N1 Neuraminidase (NA RNA using in situ RT-PCR. Results We detected NA transcripts in 100% of the previously diagnosed A (H1N1-positive samples as a cytoplasmic signal. No expression was detected by in situ RT-PCR in two Influenza-like Illness A (H1N1-negative patients using standard protocols nor in a non-related cervical cell line. In situ relative transcription levels correlated with those obtained when in vitro RT-PCR assays were performed. Partial sequences of the NA gene from A (H1N1-positive patients were obtained by the in situ RT-PCR-sequencing method. Sequence analysis showed 98% similarity with influenza viruses reported previously in other places. Conclusions We have successfully amplified specific influenza A (H1N1 NA sequences using stored clinical material; results suggest that this strategy could be useful when clinical RNA samples are quantity limited, or when poor quality is obtained. Here, we provide a very sensitive method that specifically detects the neuraminidase viral RNA in lung samples from patients who died from pneumonia caused by Influenza A (H1N1 outbreak in Mexico City.

  8. ICU-treated influenza A(H1N1 pdm09 infections more severe post pandemic than during 2009 pandemic: a retrospective analysis

    Directory of Open Access Journals (Sweden)

    Pekka Ylipalosaari

    2017-11-01

    Full Text Available Abstract Background We compared in a single mixed intensive care unit (ICU patients with influenza A(H1N1 pdm09 between pandemic and postpandemic periods. Methods Retrospective analysis of prospectively collected data in 2009–2016. Data are expressed as median (25th–75th percentile or number (percentile. Results Seventy-six influenza A(H1N1 pdm09 patients were admitted to the ICU: 16 during the pandemic period and 60 during the postpandemic period. Postpandemic patients were significantly older (60 years vs. 43 years, p < 0.001 and less likely to have epilepsy or other neurological diseases compared with pandemic patients (5 [8.3%] vs. 6 [38%], respectively; p = 0.009. Postpandemic patients were more likely than pandemic patients to have cardiovascular disease (24 [40%] vs. 1 [6%], respectively; p = 0.015, and they had higher scores on APACHE II (17 [13–22] vs. 14 [10–17], p = 0.002 and SAPS II (40 [31–51] vs. 31 [25–35], p = 0.002 upon admission to the ICU. Postpandemic patients had higher maximal SOFA score (9 [5–12] vs. 5 [4–9], respectively; p = 0.03 during their ICU stay. Postpandemic patients had more often septic shock (40 [66.7%] vs. 8 [50.0%], p = 0.042, and longer median hospital stays (15.0 vs. 8.0 days, respectively; p = 0.006. During 2015–2016, only 18% of the ICU- treated patients had received seasonal influenza vaccination. Conclusions Postpandemic ICU-treated A(H1N1 pdm09 influenza patients were older and developed more often septic shock and had longer hospital stays than influenza patients during the 2009 pandemic.

  9. Factors associated with 2009 pandemic influenza A (H1N1 vaccination acceptance among university students from India during the post-pandemic phase

    Directory of Open Access Journals (Sweden)

    Thejaswini Venkatesh

    2011-07-01

    Full Text Available Abstract Background There was a low adherence to influenza A (H1N1 vaccination program among university students and health care workers during the pandemic influenza in many parts of the world. Vaccination of high risk individuals is one of the recommendations of World Health Organization during the post-pandemic period. It is not documented about the student's knowledge, attitude and willingness to accept H1N1 vaccination during the post-pandemic period. We aimed to analyze the student's knowledge, attitude and willingness to accept H1N1 vaccination during the post-pandemic period in India. Methods Vaccine against H1N1 was made available to the students of Vellore Institute of Technology, India from September 2010. The data are based on a cross-sectional study conducted during October 2010 to January 2011 using a self-administered questionnaire with a representative sample of the student population (N = 802. Results Of the 802 respondents, only 102/802 (12.7% had been vaccinated and 105/802 (13% planned to do so in the future, while 595/802 (74% would probably or definitely not get vaccinated in the future. The highest coverage was among the female (65/102, 63.7% and non-compliance was higher among men in the group (384/595; 64.5% (p Conclusions Our study shows that the vaccination coverage among university students remains very low in the post-pandemic period and doubts about the safety and effectiveness of the vaccine are key elements in their rejection. Our results indicate a need to provide accessible information about the vaccine safety by scientific authorities and fill gaps and confusions in this regard.

  10. Fully human broadly neutralizing monoclonal antibodies against influenza A viruses generated from the memory B cells of a 2009 pandemic H1N1 influenza vaccine recipient

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Weibin [Molecular Virus Unit, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200025 (China); Chen, Aizhong [Key Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Miao, Yi [Shanghai Xuhui Central Hospital, Shanghai 200031 (China); Xia, Shengli [Center for Disease Control and Prevention of Henan Province, Zhengzhou 450016 (China); Ling, Zhiyang; Xu, Ke; Wang, Tongyan [Molecular Virus Unit, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200025 (China); Xu, Ying; Cui, Jun; Wu, Hongqiang; Hu, Guiyu; Tian, Lin; Wang, Lingling [Key Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Shu, Yuelong [Chinese Center for Disease Control and Prevention, Beijing 102206 (China); Ma, Xiaowei [Hualan Biological Bacterin Company, Xinxiang 453003 (China); Xu, Bianli; Zhang, Jin [Center for Disease Control and Prevention of Henan Province, Zhengzhou 450016 (China); Lin, Xiaojun, E-mail: linxiaojun@hualan.com [Hualan Biological Bacterin Company, Xinxiang 453003 (China); Bian, Chao, E-mail: cbian@sibs.ac.cn [Key Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Sun, Bing, E-mail: bsun@sibs.ac.cn [Molecular Virus Unit, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200025 (China); Key Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China)

    2013-01-20

    Whether the 2009 pandemic H1N1 influenza vaccine can induce heterosubtypic cross-protective anti-hemagglutinin (HA) neutralizing antibodies is an important issue. We obtained a panel of fully human monoclonal antibodies from the memory B cells of a 2009 pandemic H1N1 influenza vaccine recipient. Most of the monoclonal antibodies targeted the HA protein but not the HA1 fragment. Among the analyzed antibodies, seven mAbs exhibited neutralizing activity against several influenza A viruses of different subtypes. The conserved linear epitope targeted by the neutralizing mAbs (FIEGGWTGMVDGWYGYHH) is part of the fusion peptide on HA2. Our work suggests that a heterosubtypic neutralizing antibody response primarily targeting the HA stem region exists in recipients of the 2009 pandemic H1N1 influenza vaccine. The HA stem region contains various conserved neutralizing epitopes with the fusion peptide as an important one. This work may aid in the design of a universal influenza A virus vaccine.

  11. Fully human broadly neutralizing monoclonal antibodies against influenza A viruses generated from the memory B cells of a 2009 pandemic H1N1 influenza vaccine recipient

    International Nuclear Information System (INIS)

    Hu, Weibin; Chen, Aizhong; Miao, Yi; Xia, Shengli; Ling, Zhiyang; Xu, Ke; Wang, Tongyan; Xu, Ying; Cui, Jun; Wu, Hongqiang; Hu, Guiyu; Tian, Lin; Wang, Lingling; Shu, Yuelong; Ma, Xiaowei; Xu, Bianli; Zhang, Jin; Lin, Xiaojun; Bian, Chao; Sun, Bing

    2013-01-01

    Whether the 2009 pandemic H1N1 influenza vaccine can induce heterosubtypic cross-protective anti-hemagglutinin (HA) neutralizing antibodies is an important issue. We obtained a panel of fully human monoclonal antibodies from the memory B cells of a 2009 pandemic H1N1 influenza vaccine recipient. Most of the monoclonal antibodies targeted the HA protein but not the HA1 fragment. Among the analyzed antibodies, seven mAbs exhibited neutralizing activity against several influenza A viruses of different subtypes. The conserved linear epitope targeted by the neutralizing mAbs (FIEGGWTGMVDGWYGYHH) is part of the fusion peptide on HA2. Our work suggests that a heterosubtypic neutralizing antibody response primarily targeting the HA stem region exists in recipients of the 2009 pandemic H1N1 influenza vaccine. The HA stem region contains various conserved neutralizing epitopes with the fusion peptide as an important one. This work may aid in the design of a universal influenza A virus vaccine.

  12. Outbreak of 2009 pandemic influenza A(H1N1), Los Lagos, Chile, April-June 2009.

    Science.gov (United States)

    Pedroni, E; Garcia, M; Espinola, V; Guerrero, A; Gonzalez, C; Olea, A; Calvo, M; Martorell, B; Winkler, M; Carrasco, Mv; Vergara, Ja; Ulloa, J; Carrazana, Am; Mujica, O; Villarroel, Je; Labrana, M; Vargas, M; Gonzalez, P; Caceres, L; Zamorano, Cg; Momberg, R; Munoz, G; Rocco, J; Bosque, V; Gallardo, A; Elgueta, J; Vega, J

    2010-01-07

    On 17 May 2009, the first two cases of 2009 pandemic influenza A(H1N1) were confirmed in the Metropolitan region (Santiago, Chile). On 6 June 2009, Chile reported 500 confirmed cases, seven severe and two fatal. Because six of the severe cases and the two deaths occurred in the region of Los Lagos in southern Chile, a retrospective study was conducted using data on emergency room visits as well as laboratory viral surveillance, during the period from 1 April to 31 May, in order to establish the date of the beginning of the outbreak. From 1 to 27 June, data were collected in real time, to establish the real magnitude of the outbreak, describe its transmission, clinical severity and secondary attack rates. Confirmed cases, their household contacts and healthcare workers were interviewed. This analysis showed that the outbreak in Los Lagos started on 28 April. By 27 June, a total of 14.559 clinical cases were identified, affecting mostly 5-19 year-olds. The effective reproduction number during the initial phase (20 days) was 1.8 (1.6-2.0). Of the 190 confirmed cases with severe acute respiratory infection, 71 (37.4%) presented a risk condition or underlying illness.

  13. A duplex real-time RT-PCR assay for detecting H5N1 avian influenza virus and pandemic H1N1 influenza virus

    Directory of Open Access Journals (Sweden)

    Qin E-de

    2010-06-01

    Full Text Available Abstract A duplex real-time reverse transcriptase polymerase chain reaction (RT-PCR assay was improved for simultaneous detection of highly pathogenic H5N1 avian influenza virus and pandemic H1N1 (2009 influenza virus, which is suitable for early diagnosis of influenza-like patients and for epidemiological surveillance. The sensitivity of this duplex real-time RT-PCR assay was 0.02 TCID50 (50% tissue culture infective dose for H5N1 and 0.2 TCID50 for the pandemic H1N1, which was the same as that of each single-target RT-PCR for pandemic H1N1 and even more sensitive for H5N1 with the same primers and probes. No cross reactivity of detecting other subtype influenza viruses or respiratory tract viruses was observed. Two hundred and thirty-six clinical specimens were tested by comparing with single real-time RT-PCR and result from the duplex assay was 100% consistent with the results of single real-time RT-PCR and sequence analysis.

  14. Bayesian estimation of the dynamics of pandemic (H1N1) 2009 influenza transmission in Queensland: A space-time SIR-based model.

    Science.gov (United States)

    Huang, Xiaodong; Clements, Archie C A; Williams, Gail; Mengersen, Kerrie; Tong, Shilu; Hu, Wenbiao

    2016-04-01

    A pandemic strain of influenza A spread rapidly around the world in 2009, now referred to as pandemic (H1N1) 2009. This study aimed to examine the spatiotemporal variation in the transmission rate of pandemic (H1N1) 2009 associated with changes in local socio-environmental conditions from May 7-December 31, 2009, at a postal area level in Queensland, Australia. We used the data on laboratory-confirmed H1N1 cases to examine the spatiotemporal dynamics of transmission using a flexible Bayesian, space-time, Susceptible-Infected-Recovered (SIR) modelling approach. The model incorporated parameters describing spatiotemporal variation in H1N1 infection and local socio-environmental factors. The weekly transmission rate of pandemic (H1N1) 2009 was negatively associated with the weekly area-mean maximum temperature at a lag of 1 week (LMXT) (posterior mean: -0.341; 95% credible interval (CI): -0.370--0.311) and the socio-economic index for area (SEIFA) (posterior mean: -0.003; 95% CI: -0.004--0.001), and was positively associated with the product of LMXT and the weekly area-mean vapour pressure at a lag of 1 week (LVAP) (posterior mean: 0.008; 95% CI: 0.007-0.009). There was substantial spatiotemporal variation in transmission rate of pandemic (H1N1) 2009 across Queensland over the epidemic period. High random effects of estimated transmission rates were apparent in remote areas and some postal areas with higher proportion of indigenous populations and smaller overall populations. Local SEIFA and local atmospheric conditions were associated with the transmission rate of pandemic (H1N1) 2009. The more populated regions displayed consistent and synchronized epidemics with low average transmission rates. The less populated regions had high average transmission rates with more variations during the H1N1 epidemic period. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Intensive cytokine induction in pandemic H1N1 influenza virus infection accompanied by robust production of IL-10 and IL-6.

    Science.gov (United States)

    Yu, Xuelian; Zhang, Xi; Zhao, Baihui; Wang, Jiayu; Zhu, Zhaokui; Teng, Zheng; Shao, Junjie; Shen, Jiaren; Gao, Ye; Yuan, Zhengan; Wu, Fan

    2011-01-01

    The innate immune system is the first line of defense against viruses by inducing expression of cytokines and chemokines. Many pandemic influenza H1N1 virus [P(H1N1)] infected severe cases occur in young adults under 18 years old who were rarely seriously affected by seasonal influenza. Results regarding host cytokine profiles of P(H1N1) are ambivalent. In the present study we investigated host cytokine profiles in P(H1N1) patients and identified cytokines related to disease severity. We retrieved 77, 59, 26 and 26 sera samples from P(H1N1) and non-flu influenza like illness (non-ILIs) cases with mild symptoms (mild patients), P(H1N1) vaccinees and healthy individuals, respectively. Nine and 16 sera were from hospitalized P(H1N1) and non-ILIs patients with severe symptoms (severe patients). Cytokines of IL-1, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, IFN-γ and TNF-α were assayed by cytokine bead array, IL-17 and IL-23 measured with ELISA. Mild P(H1N1) patients produced significantly elevated IL-2, IL-12, IFN-γ, IL-6, TNF-α, IL-5, IL-10, IL-17 and IL-23 versus to healthy controls. While an overwhelming IL-6 and IL-10 production were observed in severe P(H1N1) patients. Higher IL-10 secretion in P(H1N1) vaccinees confirmed our observation that highly increased level of sera IL-6 and IL-10 in P(H1N1) patients may lead to disease progression. A comprehensive innate immune response was activated at the early stage of P(H1N1) infection with a combine Th1/Th2/Th3 cytokines production. As disease progression, a systemic production of IL-6 and IL-10 were observed in severe P(H1N1) patients. Further analysis found a strong correlation between IL-6 and IL-10 production in the severe P(H1N1) patients. IL-6 may be served as a mediator to induce IL-10 production. Highly elevated level of sera IL-6 and IL-10 in P(H1N1) patients may lead to disease progression, but the underlying mechanism awaits further detailed investigations.

  16. Intensive cytokine induction in pandemic H1N1 influenza virus infection accompanied by robust production of IL-10 and IL-6.

    Directory of Open Access Journals (Sweden)

    Xuelian Yu

    Full Text Available BACKGROUND: The innate immune system is the first line of defense against viruses by inducing expression of cytokines and chemokines. Many pandemic influenza H1N1 virus [P(H1N1] infected severe cases occur in young adults under 18 years old who were rarely seriously affected by seasonal influenza. Results regarding host cytokine profiles of P(H1N1 are ambivalent. In the present study we investigated host cytokine profiles in P(H1N1 patients and identified cytokines related to disease severity. METHODS AND PRINCIPAL FINDINGS: We retrieved 77, 59, 26 and 26 sera samples from P(H1N1 and non-flu influenza like illness (non-ILIs cases with mild symptoms (mild patients, P(H1N1 vaccinees and healthy individuals, respectively. Nine and 16 sera were from hospitalized P(H1N1 and non-ILIs patients with severe symptoms (severe patients. Cytokines of IL-1, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, IFN-γ and TNF-α were assayed by cytokine bead array, IL-17 and IL-23 measured with ELISA. Mild P(H1N1 patients produced significantly elevated IL-2, IL-12, IFN-γ, IL-6, TNF-α, IL-5, IL-10, IL-17 and IL-23 versus to healthy controls. While an overwhelming IL-6 and IL-10 production were observed in severe P(H1N1 patients. Higher IL-10 secretion in P(H1N1 vaccinees confirmed our observation that highly increased level of sera IL-6 and IL-10 in P(H1N1 patients may lead to disease progression. CONCLUSION AND SIGNIFICANCE: A comprehensive innate immune response was activated at the early stage of P(H1N1 infection with a combine Th1/Th2/Th3 cytokines production. As disease progression, a systemic production of IL-6 and IL-10 were observed in severe P(H1N1 patients. Further analysis found a strong correlation between IL-6 and IL-10 production in the severe P(H1N1 patients. IL-6 may be served as a mediator to induce IL-10 production. Highly elevated level of sera IL-6 and IL-10 in P(H1N1 patients may lead to disease progression, but the underlying mechanism awaits

  17. Immune response after one or two doses of pandemic influenza A (H1N1) monovalent, AS03-adjuvanted vaccine in HIV infected adults

    DEFF Research Database (Denmark)

    Bybeck Nielsen, Allan; Nielsen, Henriette Schjønning; Nielsen, Lars

    2012-01-01

    INTRODUCTION: Continued research is needed to evaluate and improve the immunogenicity of influenza vaccines in HIV infected patients. We aimed to determine the antibody responses after one or two doses of the AS03-adjuvanted pandemic influenza A (H1N1) vaccine in HIV infected patients. METHOD......: Following the influenza season 2009/2010, 219 HIV infected patients were included and divided into three groups depending on whether they received none (n=60), one (n=31) or two (n=128) doses of pandemic influenza A (H1N1) vaccine. At inclusion, antibody titers for all patients were analyzed and compared...... to pre-pandemic antibody titers analyzed from serum samples in a local storage facility. RESULTS: 4-9 months after a single immunization, we found a seroprotection rate of 77.4% and seroconversion rate of 67.7%. After two immunizations the rates increased significantly to seroprotection rate of 97...

  18. US school morbidity and mortality, mandatory vaccination, institution closure, and interventions implemented during the 2009 influenza A H1N1 pandemic.

    Science.gov (United States)

    Rebmann, Terri; Elliott, Michael B; Swick, Zachary; Reddick, David

    2013-03-01

    The 2009 H1N1 pandemic disproportionately affected school-aged children, but only school-based outbreak case studies have been conducted. The purposes of this study were to evaluate US academic institutions' experiences during the 2009 H1N1 pandemic in terms of infection prevention interventions implemented and to examine factors associated with school closure during the pandemic. An online survey was sent to school nurses in May through July 2011. Hierarchical logistic regressions were used to determine predictive models for having a mandatory H1N1 vaccination policy for school nurses and school closure. In all, 1,997 nurses from 26 states participated. Very few nurses (3.3%, n=65) reported having a mandatory H1N1 influenza vaccination policy; nurses were more likely than all other school employees (pnurse employed by a public health agency or hospital, and being a private school. The most commonly implemented interventions included encouraging staff and students to exercise hand hygiene and increasing classroom cleaning; least commonly implemented interventions included discouraging face-to-face meetings, training staff on H1N1 influenza and/or respiratory hygiene, and discouraging handshaking. Schools should develop and continue to improve their pandemic plans, including collaborating with community response agencies.

  19. Guillain-Barré syndrome and adjuvanted pandemic influenza A (H1N1) 2009 vaccine: Multinational case-control study in Europe

    NARCIS (Netherlands)

    J.P. Dieleman (Jeanne); S. Romio (Silvana); K. Johansen (Kari); D.M. Weibel (Daniel); J. Bonhoeffer (Jan); M.C.J.M. Sturkenboom (Miriam)

    2011-01-01

    textabstractObjective: To assess the association between pandemic influenza A (H1N1) 2009 vaccine and Guillain-Barré syndrome. Design: Case-control study. Setting: Five European countries. Participants: 104 patients with Guillain-Barré syndrome and its variant Miller-Fisher syndrome matched to one

  20. Duration of (18)F-FDG avidity in lymph nodes after pandemic H1N1v and seasonal influenza vaccination

    DEFF Research Database (Denmark)

    Thomassen, Anders; Lerberg Nielsen, Anne; Gerke, Oke

    2011-01-01

    PURPOSE: The aim of our study was to investigate the occurrence of fluorodeoxyglucose (FDG) avidity in draining axillary lymph nodes after vaccination against influenza (H1N1v pandemic and seasonal) and to determine the period of increased FDG uptake. METHODS: During December 2009, patients...

  1. Economic evaluation of the vaccination program against seasonal and pandemic A/H1N1 influenza among customs officers in Greece.

    Science.gov (United States)

    Mamma, Maria; Spandidos, Demetrios A

    2013-01-01

    Health policies from many countries recommend influenza vaccination of "high-priority" professional groups, including customs officers. Our aim was to estimate the economic impact of the vaccination program against influenza among customs officers in Greece during the 2009/2010 period. We developed a decision analytical computational simulation model including dynamic transmission elements that estimated the economic impact of various scenarios with different attack rates, symptomatic percentages and vaccination participation among customs officers. We also assessed in real-time the economic impact of the national 2009/2010 campaign against seasonal and pandemic A/H1N1 influenza. Implementing a seasonal and pandemic A/H1N1 influenza vaccination program among customs officers in Greece with a participation rate of 30%, influenza vaccination was not cost-saving in any of the studied influenza scenarios. When the participation rate reached 100%, the program was cost-saving, when the influenza attack rate was 30% and the symptomatic rate 65%. The real-time estimated mean net cost-benefit value in 2009/2010 period was -7.3 euros/custom officer. With different clinical scenarios, providing a vaccination program against seasonal and pandemic A/H1N1 influenza can incur a substantial net benefit for customs offices. However, the size of the benefit strongly depends upon the attack rate of influenza, the symptomatic rate as well as the participation rate of the customs officers in the program. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

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

    Science.gov (United States)

    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.

  3. Relative Efficacy of AS03-Adjuvanted Pandemic Influenza A(H1N1) Vaccine in Children: Results of a Controlled, Randomized Efficacy Trial

    Science.gov (United States)

    Nolan, Terry; Roy-Ghanta, Sumita; Montellano, May; Weckx, Lily; Ulloa-Gutierrez, Rolando; Lazcano-Ponce, Eduardo; Kerdpanich, Angkool; Safadi, Marco Aurélio Palazzi; Cruz-Valdez, Aurelio; Litao, Sandra; Lim, Fong Seng; de Los Santos, Abiel Mascareñas; Weber, Miguel Angel Rodriguez; Tinoco, Juan-Carlos; Mezerville, Marcela Hernandez-de; Faingezicht, Idis; Kosuwon, Pensri; Lopez, Pio; Borja-Tabora, Charissa; Li, Ping; Durviaux, Serge; Fries, Louis; Dubin, Gary; Breuer, Thomas; Innis, Bruce L.; Vaughn, David W.

    2014-01-01

    Background. The vaccine efficacy (VE) of 1 or 2 doses of AS03-adjuvanted influenza A(H1N1) vaccine relative to that of 2 doses of nonadjuvanted influenza A(H1N1) vaccine in children 6 months to <10 years of age in a multinational study conducted during 2010–2011. Methods. A total of 6145 children were randomly assigned at a ratio of 1:1:1 to receive 2 injections 21 days apart of A/California/7/2009(H1N1)-AS03 vaccine at dose 1 and saline placebo at dose 2, 2 doses 21 days apart of A/California/7/2009(H1N1)-AS03 vaccine (the Ad2 group), or 2 doses 21 days apart of nonadjuvanted A/California/7/2009(H1N1) vaccine (the NAd2 group). Active surveillance for influenza-like illnesses continued from days 14 to 385. Nose and throat samples obtained during influenza-like illnesses were tested for A/California/7/2009(H1N1), using reverse-transcriptase polymerase chain reaction. Immunogenicity, reactogenicity, and safety were assessed. Results. There were 23 cases of confirmed 2009 pandemic influenza A(H1N1) (A[H1N1]pdm09) infection for the primary relative VE analysis. The VE in the Ad2 group relative to that in the NAd2 group was 76.8% (95% confidence interval, 18.5%–93.4%). The benefit of the AS03 adjuvant was demonstrated in terms of the greater immunogenicity observed in the Ad2 group, compared with the NAd2 group. Conclusion. The 4–8-fold antigen-sparing adjuvanted pandemic influenza vaccine demonstrated superior and clinically important prevention of A(H1N1)pdm09 infection, compared with nonadjuvanted vaccine, with no observed increase in medically attended or serious adverse events. These data support the use of adjuvanted influenza vaccines during influenza pandemics. Clinical Trials Registration. NCT01051661. PMID:24652494

  4. Attack rates assessment of the 2009 pandemic H1N1 influenza A in children and their contacts: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Aharona Glatman-Freedman

    Full Text Available BACKGROUND: The recent H1N1 influenza A pandemic was marked by multiple reports of illness and hospitalization in children, suggesting that children may have played a major role in the propagation of the virus. A comprehensive detailed analysis of the attack rates among children as compared with their contacts in various settings is of great importance for understanding their unique role in influenza pandemics. METHODOLOGY/PRINCIPAL FINDINGS: We searched MEDLINE (PubMed and Embase for published studies reporting outbreak investigations with direct measurements of attack rates of the 2009 pandemic H1N1 influenza A among children, and quantified how these compare with those of their contacts. We identified 50 articles suitable for review, which reported school, household, travel and social events. The selected reports and our meta-analysis indicated that children had significantly higher attack rates as compared to adults, and that this phenomenon was observed for both virologically confirmed and clinical cases, in various settings and locations around the world. The review also provided insight into some characteristics of transmission between children and their contacts in the various settings. CONCLUSION/SIGNIFICANCE: The consistently higher attack rates of the 2009 pandemic H1N1 influenza A among children, as compared to adults, as well as the magnitude of the difference is important for understanding the contribution of children to disease burden, for implementation of mitigation strategies directed towards children, as well as more precise mathematical modeling and simulation of future influenza pandemics.

  5. Cost-effective strategies for mitigating a future influenza pandemic with H1N1 2009 characteristics.

    Directory of Open Access Journals (Sweden)

    Nilimesh Halder

    Full Text Available BACKGROUND: We performed an analysis of the cost-effectiveness of pandemic intervention strategies using a detailed, individual-based simulation model of a community in Australia together with health outcome data of infected individuals gathered during 2009-2010. The aim was to examine the cost-effectiveness of a range of interventions to determine the most cost-effective strategies suitable for a future pandemic with H1N1 2009 characteristics. METHODOLOGY/PRINCIPAL FINDINGS: Using transmissibility, age-stratified attack rates and health outcomes determined from H1N1 2009 data, we determined that the most cost-effective strategies involved treatment and household prophylaxis using antiviral drugs combined with limited duration school closure, with costs ranging from $632 to $777 per case prevented. When school closure was used as a sole intervention we found the use of limited duration school closure to be significantly more cost-effective compared to continuous school closure, a result with applicability to countries with limited access to antiviral drugs. Other social distancing strategies, such as reduced workplace attendance, were found to be costly due to productivity losses. CONCLUSION: The mild severity (low hospitalisation and case fatality rates and low transmissibility of H1N1 2009 meant that health treatment costs were dominated by the higher productivity losses arising from workplace absence due to illness and childcare requirements following school closure. Further analysis for higher transmissibility but with the same, mild severity had no effect on the overall findings.

  6. Large Scale Genome Analysis Shows that the Epitopes for Broadly Cross-Reactive Antibodies Are Predominant in the Pandemic 2009 Influenza Virus A H1N1 Strain

    Directory of Open Access Journals (Sweden)

    Edgar E. Lara-Ramírez

    2013-11-01

    Full Text Available The past pandemic strain H1N1 (A (H1N1pdm09 has now become a common component of current seasonal influenza viruses. It has changed the pre-existing immunity of the human population to succeeding infections. In the present study, a total of 14,210 distinct sequences downloaded from National Center for Biotechnology Information (NCBI database were used for the analysis. The epitope compositions in A (H1N1pdm09, classic seasonal strains, swine strains as well as highly virulent avian strain H5N1, identified with the aid of the Immune Epitope DataBase (IEDB, were compared at genomic level. The result showed that A (H1N1 pdm09 contains the 90% of B-cell epitopes for broadly cross-reactive antibodies (EBCA, which is in consonance with the recent reports on the experimental identification of new epitopes or antibodies for this virus and the binding tests with influenza virus protein HA of different subtypes. Our analysis supports that high proportional EBCA depends on the epitope pattern of A (H1N1pdm09 virus. This study may be helpful for better understanding of A (H1N1pdm09 and the production of new influenza vaccines.

  7. Differential host determinants contribute to the pathogenesis of 2009 pandemic H1N1 and human H5N1 influenza A viruses in experimental mouse models.

    Science.gov (United States)

    Otte, Anna; Sauter, Martina; Alleva, Lisa; Baumgarte, Sigrid; Klingel, Karin; Gabriel, Gülsah

    2011-07-01

    Influenza viruses are responsible for high morbidities in humans and may, eventually, cause pandemics. Herein, we compared the pathogenesis and host innate immune responses of a seasonal H1N1, two 2009 pandemic H1N1, and a human H5N1 influenza virus in experimental BALB/c and C57BL/6J mouse models. We found that both 2009 pandemic H1N1 isolates studied (A/Hamburg/05/09 and A/Hamburg/NY1580/09) were low pathogenic in BALB/c mice [log mouse lethal dose 50 (MLD(50)) >6 plaque-forming units (PFU)] but displayed remarkable differences in virulence in C57BL/6J mice. A/Hamburg/NY1580/09 was more virulent (logMLD(50) = 3.5 PFU) than A/Hamburg/05/09 (logMLD(50) = 5.2 PFU) in C57BL/6J mice. In contrast, the H5N1 influenza virus was more virulent in BALB/c mice (logMLD(50) = 0.3 PFU) than in C57BL/6J mice (logMLD(50) = 1.8 PFU). Seasonal H1N1 influenza revealed marginal pathogenicity in BALB/c or C57BL/6J mice (logMLD(50) >6 PFU). Enhanced susceptibility of C57BL/6J mice to pandemic H1N1 correlated with a depressed cytokine response. In contrast, enhanced H5N1 virulence in BALB/c mice correlated with an elevated proinflammatory cytokine response. These findings highlight that host determinants responsible for the pathogenesis of 2009 pandemic H1N1 influenza viruses are different from those contributing to H5N1 pathogenesis. Our results show, for the first time to our knowledge, that the C57BL/6J mouse strain is more appropriate for the evaluation and identification of intrinsic pathogenicity markers of 2009 pandemic H1N1 influenza viruses that are "masked" in BALB/c mice. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  8. The impact that the influenza A (H1N1) pandemic had on news reporting in the state of Paraná, Brazil.

    Science.gov (United States)

    Maciel-Lima, Sandra Mara; Rasia, José Miguel; Bagatelli, Rodrigo Cechelero; Gontarski, Giseli; Colares, Máximo José D

    2015-01-01

    This study aims to analyze how influenza A (H1N1) in 2009 was reported in the state of Paraná. A total of 189 articles were analyzed in two newspapers from Paraná. Pursuant to analysis, four themes were identified: the spread of the virus; the pandemic and fear; influenza in the health service; and influenza in public policies. By studying how influenza A was reported in the media, it was possible to see the social impact that the H1N1 pandemic represented for society, presenting challenges for public institutions and ordinary citizens, who sensed that they were in a high-risk group exposed to a potentially lethal virus. This disease radically changed the habits of a globalized community seeking to escape from vulnerability.

  9. The impact that the influenza A (H1N1 pandemic had on news reporting in the state of Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Sandra Mara Maciel-Lima

    2015-03-01

    Full Text Available This study aims to analyze how influenza A (H1N1 in 2009 was reported in the state of Paraná. A total of 189 articles were analyzed in two newspapers from Paraná. Pursuant to analysis, four themes were identified: the spread of the virus; the pandemic and fear; influenza in the health service; and influenza in public policies. By studying how influenza A was reported in the media, it was possible to see the social impact that the H1N1 pandemic represented for society, presenting challenges for public institutions and ordinary citizens, who sensed that they were in a high-risk group exposed to a potentially lethal virus. This disease radically changed the habits of a globalized community seeking to escape from vulnerability.

  10. In vitro reassortment between endemic H1N2 and 2009 H1N1 pandemic swine influenza viruses generates attenuated viruses.

    Directory of Open Access Journals (Sweden)

    Ben M Hause

    Full Text Available The pandemic H1N1 (pH1N1 influenza virus was first reported in humans in the spring of 2009 and soon thereafter was identified in numerous species, including swine. Reassortant viruses, presumably arising from the co-infection of pH1N1 and endemic swine influenza virus (SIV, were subsequently identified from diagnostic samples collected from swine. In this study, co-infection of swine testicle (ST cells with swine-derived endemic H1N2 (MN745 and pH1N1 (MN432 yielded two reassortant H1N2 viruses (R1 and R2, both possessing a matrix gene derived from pH1N1. In ST cells, the reassortant viruses had growth kinetics similar to the parental H1N2 virus and reached titers approximately 2 log(10 TCID(50/mL higher than the pH1N1 virus, while in A549 cells these viruses had similar growth kinetics. Intranasal challenge of pigs with H1N2, pH1N1, R1 or R2 found that all viruses were capable of infecting and transmitting between direct contact pigs as measured by real time reverse transcription PCR of nasal swabs. Lung samples were also PCR-positive for all challenge groups and influenza-associated microscopic lesions were detected by histology. Interestingly, infectious virus was detected in lung samples for pigs challenged with the parental H1N2 and pH1N1 at levels significantly higher than either reassortant virus despite similar levels of viral RNA. Results of our experiment suggested that the reassortant viruses generated through in vitro cell culture system were attenuated without gaining any selective growth advantage in pigs over the parental lineages. Thus, reassortant influenza viruses described in this study may provide a good system to study genetic basis of the attenuation and its mechanism.

  11. Absenteeism in schools during the 2009 influenza A(H1N1) pandemic: a useful tool for early detection of influenza activity in the community?

    Science.gov (United States)

    Kara, E O; Elliot, A J; Bagnall, H; Foord, D G F; Pnaiser, R; Osman, H; Smith, G E; Olowokure, B

    2012-07-01

    Certain influenza outbreaks, including the 2009 influenza A(H1N1) pandemic, can predominantly affect school-age children. Therefore the use of school absenteeism data has been considered as a potential tool for providing early warning of increasing influenza activity in the community. This study retrospectively evaluates the usefulness of these data by comparing them with existing syndromic surveillance systems and laboratory data. Weekly mean percentages of absenteeism in 373 state schools (children aged 4-18 years) in Birmingham, UK, from September 2006 to September 2009, were compared with established syndromic surveillance systems including a telephone health helpline, a general practitioner sentinel network and laboratory data for influenza. Correlation coefficients were used to examine the relationship between each syndromic system. In June 2009, school absenteeism generally peaked concomitantly with the existing influenza surveillance systems in England. Weekly school absenteeism surveillance would not have detected pandemic influenza A(H1N1) earlier but daily absenteeism data and the development of baselines could improve the timeliness of the system.

  12. Influenza A (H1N1) organising pneumonia.

    Science.gov (United States)

    Torrego, Alfons; Pajares, Virginia; Mola, Anna; Lerma, Enrique; Franquet, Tomás

    2010-04-27

    In November 2009, countries around the world reported confirmed cases of pandemic influenza H1N1, including over 6000 deaths. No peak in activity has been seen. The most common causes of death are pneumonia and acute respiratory distress syndrome. We report a case of a 55-year-old woman who presented with organising pneumonia associated with influenza A (H1N1) infection confirmed by transbronchial lung biopsy. Organising pneumonia should also be considered as a possible complication of influenza A (H1N1) infection, given that these patients can benefit from early diagnosis and appropriate specific management.

  13. Pandemic influenza A (H1N1 2009: epidemiological analysis of cases in a tropical/semi-arid region of Brazil

    Directory of Open Access Journals (Sweden)

    Roberto da Justa Pires Neto

    2013-04-01

    Full Text Available Introduction The year 2009 marked the beginning of a pandemic caused by a new variant of influenza A (H1N1. After spreading through North America, the pandemic influenza virus (H1N1 2009 spread rapidly throughout the world. The aim of this study was to describe the clinical and epidemiological characteristics of cases of pandemic influenza in a tropical/semi-arid region of Brazil. Methods A retrospective study analyzed all suspected cases of pandemic influenza (H1N1 2009 reported in the Ceará State through the National Information System for Notifiable Diseases during the pandemic period between 28 April, 2009 and November 25, 2010. Results A total of 616 suspected cases were notified, 58 (9.4% in the containment phase and 558 (90.6% in the mitigation phase. Most cases were of affected young people resident in the City of Fortaleza, the largest urban center in the State of Ceará. The most frequent symptoms presented by the cases with confirmed infection were fever, cough, myalgia, arthralgia, and nasal congestion. Mortality rate was 0.0009/1,000 inhabitants and lethality was 5.6%. Deaths were observed only in the mitigation phase. Mortality rates were similar for both sexes but were higher in the age group under 5 years. Conclusions The study suggests that the influenza A (H1N1 pandemic in this tropical/semi-arid region had a lower magnitude when compared to states in the Southern and Southeastern regions of Brazil.

  14. Humoral and cell-mediated immunity to pandemic H1N1 influenza in a Canadian cohort one year post-pandemic: implications for vaccination.

    Directory of Open Access Journals (Sweden)

    Lisa E Wagar

    Full Text Available We evaluated a cohort of Canadian donors for T cell and antibody responses against influenza A/California/7/2009 (pH1N1 at 8-10 months after the 2nd pandemic wave by flow cytometry and microneutralization assays. Memory CD8 T cell responses to pH1N1 were detectable in 58% (61/105 of donors. These responses were largely due to cross-reactive CD8 T cell epitopes as, for those donors tested, similar recall responses were obtained to A/California 2009 and A/PR8 1934 H1N1 Hviruses. Longitudinal analysis of a single infected individual showed only a small and transient increase in neutralizing antibody levels, but a robust CD8 T cell response that rose rapidly post symptom onset, peaking at 3 weeks, followed by a gradual decline to the baseline levels seen in a seroprevalence cohort post-pandemic. The magnitude of the influenza-specific CD8 T cell memory response at one year post-pandemic was similar in cases and controls as well as in vaccinated and unvaccinated donors, suggesting that any T cell boosting from infection was transient. Pandemic H1-specific antibodies were only detectable in approximately half of vaccinated donors. However, those who were vaccinated within a few months following infection had the highest persisting antibody titers, suggesting that vaccination shortly after influenza infection can boost or sustain antibody levels. For the most part the circulating influenza-specific T cell and serum antibody levels in the population at one year post-pandemic were not different between cases and controls, suggesting that natural infection does not lead to higher long term T cell and antibody responses in donors with pre-existing immunity to influenza. However, based on the responses of one longitudinal donor, it is possible for a small population of pre-existing cross-reactive memory CD8 T cells to expand rapidly following infection and this response may aid in viral clearance and contribute to a lessening of disease severity.

  15. The influence of climatic conditions on the transmission dynamics of the 2009 A/H1N1 influenza pandemic in Chile.

    Science.gov (United States)

    Chowell, Gerardo; Towers, Sherry; Viboud, Cécile; Fuentes, Rodrigo; Sotomayor, Viviana; Simonsen, Lone; Miller, Mark A; Lima, Mauricio; Villarroel, Claudia; Chiu, Monica; Villarroel, Jose E; Olea, Andrea

    2012-11-13

    The role of demographic factors, climatic conditions, school cycles, and connectivity patterns in shaping the spatio-temporal dynamics of pandemic influenza is not clearly understood. Here we analyzed the spatial, age and temporal evolution of the 2009 A/H1N1 influenza pandemic in Chile, a southern hemisphere country covering a long and narrow strip comprising latitudes 17°S to 56°S. We analyzed the dissemination patterns of the 2009 A/H1N1 pandemic across 15 regions of Chile based on daily hospitalizations for severe acute respiratory disease and laboratory confirmed A/H1N1 influenza infection from 01-May to 31-December, 2009. We explored the association between timing of pandemic onset and peak pandemic activity and several geographical and demographic indicators, school vacations, climatic factors, and international passengers. We also estimated the reproduction number (R) based on the growth rate of the exponential pandemic phase by date of symptoms onset, estimated using maximum likelihood methods. While earlier pandemic onset was associated with larger population size, there was no association with connectivity, demographic, school or climatic factors. In contrast, there was a latitudinal gradient in peak pandemic timing, representing a 16-39-day lag in disease activity from the southern regions relative to the northernmost region (P humidity explained 68.5% of the variability in peak timing (P = 0.01). In addition, there was a decreasing gradient in reproduction number from south to north Chile (P humidity. The latitudinal gradient in timing of pandemic activity was accompanied by a gradient in reproduction number (P < 0.0001). Intensified surveillance strategies in colder and drier southern regions could lead to earlier detection of pandemic influenza viruses and improved control outcomes.

  16. Analysis of host responses and fitness in different pandemic H1N1 (2009) influenza virus in mice and ferrets

    OpenAIRE

    Martínez Orellana, Pamela Analía

    2014-01-01

    La gripe es un problema de salud pública en todo el mundo, siendo una de las enfermedades infecciosas más comunes y una patología de las vías aéreas altamente contagiosa. Desde abril de 2009, un nuevo virus de influenza A H1N1, con origen porcino dio lugar a la aparición de brotes en todo el mundo siendo declarada posteriormente como una situación de pandemia. Hoy en día el virus pdmH1N1 de 2009 continúa en circulación, generalmente provocando infecciones leves y autolimitadas. Sin embargo, u...

  17. PD-L1 Expression Induced by the 2009 Pandemic Influenza A(H1N1 Virus Impairs the Human T Cell Response

    Directory of Open Access Journals (Sweden)

    Nuriban Valero-Pacheco

    2013-01-01

    Full Text Available PD-L1 expression plays a critical role in the impairment of T cell responses during chronic infections; however, the expression of PD-L1 on T cells during acute viral infections, particularly during the pandemic influenza virus (A(H1N1pdm09, and its effects on the T cell response have not been widely explored. We found that A(H1N1pdm09 virus induced PD-L1 expression on human dendritic cells (DCs and T cells, as well as PD-1 expression on T cells. PD-L1 expression impaired the T cell response against A(H1N1pdm09 by promoting CD8+ T cell death and reducing cytokine production. Furthermore, we found increased PD-L1 expression on DCs and T cells from influenza-infected patients from the first and second 2009 pandemic waves in Mexico City. PD-L1 expression on CD8+ T cells correlated inversely with T cell proportions in patients infected with A(H1N1pdm09. Therefore, PD-L1 expression on DCs and T cells could be associated with an impaired T cell response during acute infection with A(H1N1pdm09 virus.

  18. Searching for sharp drops in the incidence of pandemic A/H1N1 influenza by single year of age.

    Directory of Open Access Journals (Sweden)

    Jessica Hartman Jacobs

    Full Text Available During the 2009 H1N1 pandemic (pH1N1, morbidity and mortality sparing was observed among the elderly population; it was hypothesized that this age group benefited from immunity to pH1N1 due to cross-reactive antibodies generated from prior infection with antigenically similar influenza viruses. Evidence from serologic studies and genetic similarities between pH1N1 and historical influenza viruses suggest that the incidence of pH1N1 cases should drop markedly in age cohorts born prior to the disappearance of H1N1 in 1957, namely those at least 52-53 years old in 2009, but the precise range of ages affected has not been delineated.To test for any age-associated discontinuities in pH1N1 incidence, we aggregated laboratory-confirmed pH1N1 case data from 8 jurisdictions in 7 countries, stratified by single year of age, sex (when available, and hospitalization status. Using single year of age population denominators, we generated smoothed curves of the weighted risk ratio of pH1N1 incidence, and looked for sharp drops at varying age bandwidths, defined as a significantly negative second derivative. Analyses stratified by hospitalization status and sex were used to test alternative explanations for observed discontinuities. We found that the risk of laboratory-confirmed infection with pH1N1 declines with age, but that there was a statistically significant leveling off or increase in risk from about 45 to 50 years of age, after which a sharp drop in risk occurs until the late fifties. This trend was more pronounced in hospitalized cases and in women and was independent of the choice in smoothing parameters. The age range at which the decline in risk accelerates corresponds to the cohort born between 1951-1959 (hospitalized and 1953-1960 (not hospitalized.The reduced incidence of pH1N1 disease in older individuals shows a detailed age-specific pattern consistent with protection conferred by exposure to influenza A/H1N1 viruses circulating before 1957.

  19. Determination of preventive behaviors for pandemic influenza A/H1N1 based on protection motivation theory among female high school students in Isfahan, Iran.

    Science.gov (United States)

    Sharifirad, Gholamreza; Yarmohammadi, Parastoo; Sharifabad, Mohammad Ali Morowati; Rahaei, Zohreh

    2014-01-01

    Influenza A/H1N1 pandemic has recently threatened the health of world's population more than ever. Non-pharmaceutical measures are important to prevent the spread of influenza A/H1N1 and to prevent a pandemic. Effective influenza pandemic management requires understanding of the factors influencing preventive behavioral. This study reports on predictors of students' preventive behaviors for pandemic influenza A/H1N1 using variables based on the protection motivation theory (PMT). In a cross-sectional study, multiple-stage randomized sampling was used to select 300 female students in Isfahan who completed a questionnaire in December 2009. Data were collected using a self-report questionnaire based on PMT. The statistical analysis of the data included bivariate correlations, Mann-Whitney, Kruskal-Wallis, and linear regression. The mean age of participants was 15.62 (SE = 1.1) years old. Majority of participants were aware regarding pandemic influenza A/H1N1 (87.3%, 262 out of 300). Results showed that, protection motivation was highly significant relationship with preventive behavior and predicted 34% of its variance. We found all of the variables with the exception of perceived susceptibility, perceived severity, and response cost were related with protection motivation and explained 22% of its variance. Promotion of students' self-efficacy, and intention to protect themselves from a health threat should be priorities of any programs aimed at promoting preventive behaviors among students. It is also concluded that the protection motivation theory may be used in developing countries, like Iran, as a framework for prevention interventions in an attempt to improve the preventive behaviors of students.

  20. Pandemic influenza A(H1N1) outbreak among a group of medical students who traveled to the Dominican Republic.

    Science.gov (United States)

    Vilella, Anna; Serrano, Beatriz; Marcos, Maria A; Serradesanferm, Anna; Mensa, Josep; Hayes, Edward; Anton, Andres; Rios, Jose; Pumarola, Tomas; Trilla, Antoni

    2012-01-01

    From the beginning of the influenza pandemic until the time the outbreak described here was detected, 77,201 cases of pandemic influenza A(H1N1) with 332 deaths had been reported worldwide, mostly in the United States and Mexico. All of the cases reported in Spain until then had a recent history of travel to Mexico, the Dominican Republic, or Chile. We describe an outbreak of influenza among medical students who traveled from Spain to the Dominican Republic in June 2009. We collected diagnostic samples and clinical histories from consenting medical students who had traveled to the Dominican Republic and from their household contacts after their return to Spain. Of 113 students on the trip, 62 (55%) developed symptoms; 39 (45%) of 86 students tested had laboratory evidence of influenza A(H1N1) infection. Most students developed symptoms either just before departure from the Dominican Republic or within days of returning to Spain. The estimated secondary attack rate of influenza-like illness among residential contacts of ill students after return to Spain was 2.1%. The attack rate of influenza A(H1N1) can vary widely depending on the circumstances of exposure. We report a high attack rate among a group of traveling medical students but a much lower secondary attack rate among their contacts after return from the trip. These findings may aid the development of recommendations to prevent influenza. © 2011 International Society of Travel Medicine.

  1. CD4+/CD8+ T lymphocytes imbalance in children with severe 2009 pandemic influenza A (H1N1 pneumonia

    Directory of Open Access Journals (Sweden)

    Ji Eun Kim

    2011-05-01

    Full Text Available Purpose : This study was conducted to investigate the immune responses of children with moderate and severe novel influenza A virus (H1N1 pneumonia, and to compare their clinical and immunological findings with those of control subjects. Methods : Thirty-two admitted patients with H1N1 pneumonia were enrolled in the study. The clinical profiles, humoral and cell-mediated immune responses of the 16 H1N1 pneumonia patients who were admitted to the pediatric intensive care unit (severe pneumonia group, 16 H1N1 pneumonia patients admitted to the pediatric general ward (moderate pneumonia group and 13 control subjects (control group were measured. Results : Total lymphocyte counts were significantly lower in patients with H1N1 pneumonia than in the control group (P=0.02. The number of CD4+ T lymphocytes was significantly lower in the severe pneumonia group (411.5±253.5/μL than in the moderate pneumonia (644.9±291.1/μL, P=0.04 and control (902.5±461.2/μL, P=0.01 groups. However, the number of CD8+ T lymphocytes was significantly higher in the severe pneumonia group (684.2±420.8/μL than in the moderate pneumonia (319.7±176.6/μL, P=0.02 and control (407.2±309.3/μL, P=0.03 groups. The CD4+/CD8+ T lymphocytes ratio was significantly lower in the severe pneumonia group (0.86±0.24 than in the moderate pneumonia (1.57±0.41, P=0.01 and control (1.61±0.49, P=0.01 groups. The serum levels of immunoglobulin G, immunoglobulin M and immunoglobulin E were significantly higher in the severe pneumonia group than in the 2 other groups. Conclusion : The results of this study suggest that increased humoral immune responses and the differences in the CD4+ and CD8+ T lymphocyte profiles, and imbalance of their ratios may be related to the severity of H1N1 pneumonia in children.

  2. Mutation analysis of 2009 pandemic influenza A(H1N1 viruses collected in Japan during the peak phase of the pandemic.

    Directory of Open Access Journals (Sweden)

    Jean-Étienne Morlighem

    Full Text Available BACKGROUND: Pandemic influenza A(H1N1 virus infection quickly circulated worldwide in 2009. In Japan, the first case was reported in May 2009, one month after its outbreak in Mexico. Thereafter, A(H1N1 infection spread widely throughout the country. It is of great importance to profile and understand the situation regarding viral mutations and their circulation in Japan to accumulate a knowledge base and to prepare clinical response platforms before a second pandemic (pdm wave emerges. METHODOLOGY: A total of 253 swab samples were collected from patients with influenza-like illness in the Osaka, Tokyo, and Chiba areas both in May 2009 and between October 2009 and January 2010. We analyzed partial sequences of the hemagglutinin (HA and neuraminidase (NA genes of the 2009 pdm influenza virus in the collected clinical samples. By phylogenetic analysis, we identified major variants of the 2009 pdm influenza virus and critical mutations associated with severe cases, including drug-resistance mutations. RESULTS AND CONCLUSIONS: Our sequence analysis has revealed that both HA-S220T and NA-N248D are major non-synonymous mutations that clearly discriminate the 2009 pdm influenza viruses identified in the very early phase (May 2009 from those found in the peak phase (October 2009 to January 2010 in Japan. By phylogenetic analysis, we found 14 micro-clades within the viruses collected during the peak phase. Among them, 12 were new micro-clades, while two were previously reported. Oseltamivir resistance-related mutations, i.e., NA-H275Y and NA-N295S, were also detected in sporadic cases in Osaka and Tokyo.

  3. Adoption of preventive measures during and after the 2009 influenza A (H1N1) virus pandemic peak in Spain.

    Science.gov (United States)

    Agüero, Fernando; Adell, Manel Nebot; Pérez Giménez, Anna; López Medina, María José; Garcia Continente, Xavier

    2011-09-01

    This study describes the preventive measures adopted by the Spanish population towards 2009 influenza A (H1N1) virus and their associated factors. An anonymous computer-assisted telephone interview survey was conducted in Spain in December 2009 and February 2010. Respondents were asked about their perceptions of influenza A (H1N1) virus and the preventive measures adopted. Factors associated with the adoption of preventive measures were assessed by logistic regression analyses. Out of 4892 households approached, 1627 valid responses were obtained (response rate of 33.3%). The most commonly adopted preventive measures were respiratory hygiene and hand washing. Factors independently associated with the adoption of the preventive measures recommended by the Spanish Ministry of Health were female gender, higher educational level, size of municipality of residence >50,000 inhabitants, high perceived susceptibility to infection, high perceived effectiveness of the measures and high perceived usefulness of the information provided by the government. The presence of school-aged children in household was associated with purchasing masks and hand sanitizer. In addition to demographic factors, modifiable factors such as personal beliefs and expectations play a role in the adoption of preventive measures. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Experiences after Twenty Months with Pandemic Influenza A (H1N1) 2009 Infection in the Naïve Norwegian Pig Population

    Science.gov (United States)

    Gjerset, B.; Er, C.; Løtvedt, S.; Jørgensen, A.; Hungnes, O.; Lium, B.; Germundsson, A.

    2011-01-01

    Pandemic (H1N1) 2009 influenza A virus was detected in Norwegian pigs in October 2009. Until then, Norway was regarded free of swine influenza. Intensified screening revealed 91 positive herds within three months. The virus was rapidly transmitted to the susceptible population, including closed breeding herds with high biosecurity. Humans were important for the introduction as well as spread of the virus to pigs. Mild or no clinical signs were observed in infected pigs. Surveillance of SIV in 2010 revealed that 41% of all the Norwegian pig herds had antibodies to pandemic (H1N1) 2009 virus. Furthermore, this surveillance indicated that pigs born in positive herds after the active phase did not seroconvert, suggesting no ongoing infection in the herds. However, results from surveillance in 2011 show a continuing spread of the infection in many herds, either caused by new introduction or by virus circulation since 2009. PMID:23074654

  5. Guillain-Barré syndrome and adjuvanted pandemic influenza A (H1N1) 2009 vaccine: multinational case-control study in Europe

    OpenAIRE

    Dieleman, Jeanne; Romio, Silvana; Johansen, Kari; Weibel, Daniel; Bonhoeffer, Jan; Sturkenboom, Miriam

    2011-01-01

    textabstractObjective: To assess the association between pandemic influenza A (H1N1) 2009 vaccine and Guillain-Barré syndrome. Design: Case-control study. Setting: Five European countries. Participants: 104 patients with Guillain-Barré syndrome and its variant Miller-Fisher syndrome matched to one or more controls. Case status was classified according to the Brighton Collaboration definition. Controls were matched to cases on age, sex, index date, and country. Main outcome measures: Relative ...

  6. A/H1N1 pandemic influenza vaccination: A retrospective evaluation of adverse maternal, fetal and neonatal outcomes in a cohort of pregnant women in Italy.

    Science.gov (United States)

    Fabiani, Massimo; Bella, Antonino; Rota, Maria C; Clagnan, Elena; Gallo, Tolinda; D'Amato, Maurizio; Pezzotti, Patrizio; Ferrara, Lorenza; Demicheli, Vittorio; Martinelli, Domenico; Prato, Rosa; Rizzo, Caterina

    2015-05-05

    Although concerns about safety of influenza vaccination during pregnancy have been raised in the past, vaccination of pregnant women was recommended in many countries during the 2009 A/H1N1 pandemic influenza. A retrospective cohort study was conducted to evaluate the risk of adverse maternal, fetal and neonatal outcomes among pregnant women vaccinated with a MF59-adjuvanted A/H1N1 pandemic influenza vaccine. The study was carried out in four Italian regions (Piemonte, Friuli-Venezia-Giulia, Lazio, and Puglia) among 102,077 pregnant women potentially exposed during the second or third trimester of gestation to the vaccination campaign implemented in 2009/2010. Based on data retrieved from the regional administrative databases, the statistical analysis was performed using the Cox proportional-hazards model, adjusting for the propensity score to account for the potential confounding effect due to the socio-demographic characteristics and the clinical and reproductive history of women. A total of 100,332 pregnant women were eligible for the analysis. Of these, 2003 (2.0%) received the A/H1N1 pandemic influenza vaccination during the second or third trimester of gestation. We did not observe any statistically significant association between the A/H1N1 pandemic influenza vaccination and different maternal outcomes (hospital admissions for influenza, pneumonia, hypertension, eclampsia, diabetes, thyroid disease, and anaemia), fetal outcomes (fetal death after the 22nd gestational week) and neonatal outcomes (pre-term birth, low birth weight, low 5-min Apgar score, and congenital malformations). Pre-existing health-risk conditions (hospital admissions and drug prescriptions for specific diseases before the onset of pregnancy) were observed more frequently among vaccinated women, thus suggesting that concomitant chronic conditions increased vaccination uptake. The results of this study add some evidence on the safety of A/H1N1 pandemic influenza vaccination during

  7. Situational awareness and health protective responses to pandemic influenza A (H1N1 in Hong Kong: a cross-sectional study.

    Directory of Open Access Journals (Sweden)

    Qiuyan Liao

    2010-10-01

    Full Text Available Whether information sources influence health protective behaviours during influenza pandemics or other emerging infectious disease epidemics is uncertain.Data from cross-sectional telephone interviews of 1,001 Hong Kong adults in June, 2009 were tested against theory and data-derived hypothesized associations between trust in (formal/informal information, understanding, self-efficacy, perceived susceptibility and worry, and hand hygiene and social distancing using Structural Equation Modelling with multigroup comparisons.Trust in formal (government/media information about influenza was associated with greater reported understanding of A/H1N1 cause (β = 0.36 and A/H1N1 prevention self-efficacy (β = 0.25, which in turn were associated with more hand hygiene (β = 0.19 and β = 0.23, respectively. Trust in informal (interpersonal information was negatively associated with perceived personal A/H1N1 susceptibility (β = -0.21, which was negatively associated with perceived self-efficacy (β = -0.42 but positively associated with influenza worry (β = 0.44. Trust in informal information was positively associated with influenza worry (β = 0.16 which was in turn associated with greater social distancing (β = 0.36. Multigroup comparisons showed gender differences regarding paths from trust in formal information to understanding of A/H1N1 cause, trust in informal information to understanding of A/H1N1 cause, and understanding of A/H1N1 cause to perceived self-efficacy.Trust in government/media information was more strongly associated with greater self-efficacy and handwashing, whereas trust in informal information was strongly associated with perceived health threat and avoidance behaviour. Risk communication should consider the effect of gender differences.

  8. Situational awareness and health protective responses to pandemic influenza A (H1N1) in Hong Kong: a cross-sectional study.

    Science.gov (United States)

    Liao, Qiuyan; Cowling, Benjamin; Lam, Wing Tak; Ng, Man Wai; Fielding, Richard

    2010-10-12

    Whether information sources influence health protective behaviours during influenza pandemics or other emerging infectious disease epidemics is uncertain. Data from cross-sectional telephone interviews of 1,001 Hong Kong adults in June, 2009 were tested against theory and data-derived hypothesized associations between trust in (formal/informal) information, understanding, self-efficacy, perceived susceptibility and worry, and hand hygiene and social distancing using Structural Equation Modelling with multigroup comparisons. Trust in formal (government/media) information about influenza was associated with greater reported understanding of A/H1N1 cause (β = 0.36) and A/H1N1 prevention self-efficacy (β = 0.25), which in turn were associated with more hand hygiene (β = 0.19 and β = 0.23, respectively). Trust in informal (interpersonal) information was negatively associated with perceived personal A/H1N1 susceptibility (β = -0.21), which was negatively associated with perceived self-efficacy (β = -0.42) but positively associated with influenza worry (β = 0.44). Trust in informal information was positively associated with influenza worry (β = 0.16) which was in turn associated with greater social distancing (β = 0.36). Multigroup comparisons showed gender differences regarding paths from trust in formal information to understanding of A/H1N1 cause, trust in informal information to understanding of A/H1N1 cause, and understanding of A/H1N1 cause to perceived self-efficacy. Trust in government/media information was more strongly associated with greater self-efficacy and handwashing, whereas trust in informal information was strongly associated with perceived health threat and avoidance behaviour. Risk communication should consider the effect of gender differences.

  9. Outbreak of H3N2 influenza at a US military base in Djibouti during the H1N1 pandemic of 2009.

    Directory of Open Access Journals (Sweden)

    Michael T Cosby

    Full Text Available BACKGROUND: Influenza pandemics have significant operational impact on deployed military personnel working in areas throughout the world. The US Department of Defense global influenza-like illness (ILI surveillance network serves an important role in establishing baseline trends and can be leveraged to respond to outbreaks of respiratory illness. OBJECTIVE: We identified and characterized an operationally unique outbreak of H3N2 influenza at Camp Lemonnier, Djibouti occurring simultaneously with the H1N1 pandemic of 2009 [A(H1N1pdm09]. METHODS: Enhanced surveillance for ILI was conducted at Camp Lemonnier in response to local reports of a possible outbreak during the A(H1N1pdm09 pandemic. Samples were collected from consenting patients presenting with ILI (utilizing a modified case definition and who completed a case report form. Samples were cultured and analyzed using standard real-time reverse transcriptase PCR (rt-RT-PCR methodology and sequenced genetic material was phylogenetically compared to other published strains. RESULTS: rt-RT-PCR and DNA sequencing revealed that 25 (78% of the 32 clinical samples collected were seasonal H3N2 and only 2 (6% were A(H1N1pdm09 influenza. The highest incidence of H3N2 occurred during the month of May and 80% of these were active duty military personnel. Phylogenetic analysis revealed that sequenced H3N2 strains were genetically similar to 2009 strains from the United States of America, Australia, and South east Asia. CONCLUSIONS: This outbreak highlights challenges in the investigation of influenza among deployed military populations and corroborates the public health importance of maintaining surveillance systems for ILI that can be enhanced locally when needed.

  10. Outbreak of H3N2 influenza at a US military base in Djibouti during the H1N1 pandemic of 2009.

    Science.gov (United States)

    Cosby, Michael T; Pimentel, Guillermo; Nevin, Remington L; Fouad Ahmed, Salwa; Klena, John D; Amir, Ehab; Younan, Mary; Browning, Robert; Sebeny, Peter J

    2013-01-01

    Influenza pandemics have significant operational impact on deployed military personnel working in areas throughout the world. The US Department of Defense global influenza-like illness (ILI) surveillance network serves an important role in establishing baseline trends and can be leveraged to respond to outbreaks of respiratory illness. We identified and characterized an operationally unique outbreak of H3N2 influenza at Camp Lemonnier, Djibouti occurring simultaneously with the H1N1 pandemic of 2009 [A(H1N1)pdm09]. Enhanced surveillance for ILI was conducted at Camp Lemonnier in response to local reports of a possible outbreak during the A(H1N1)pdm09 pandemic. Samples were collected from consenting patients presenting with ILI (utilizing a modified case definition) and who completed a case report form. Samples were cultured and analyzed using standard real-time reverse transcriptase PCR (rt-RT-PCR) methodology and sequenced genetic material was phylogenetically compared to other published strains. rt-RT-PCR and DNA sequencing revealed that 25 (78%) of the 32 clinical samples collected were seasonal H3N2 and only 2 (6%) were A(H1N1)pdm09 influenza. The highest incidence of H3N2 occurred during the month of May and 80% of these were active duty military personnel. Phylogenetic analysis revealed that sequenced H3N2 strains were genetically similar to 2009 strains from the United States of America, Australia, and South east Asia. This outbreak highlights challenges in the investigation of influenza among deployed military populations and corroborates the public health importance of maintaining surveillance systems for ILI that can be enhanced locally when needed.

  11. Media use and communication inequalities in a public health emergency: a case study of 2009-2010 pandemic influenza A virus subtype H1N1.

    Science.gov (United States)

    Lin, Leesa; Jung, Minsoo; McCloud, Rachel F; Viswanath, Kasisomayajula

    2014-01-01

    Studies have shown that differences among individuals and social groups in accessing and using information on health and specific threats have an impact on their knowledge and behaviors. These differences, characterized as communication inequalities, may hamper the strength of a society's response to a public health emergency. Such inequalities not only make vulnerable populations subject to a disproportionate burden of adversity, but also compromise the public health system's efforts to prevent and respond to pandemic influenza outbreaks. We investigated the effect of socioeconomic status (SES) and health communication behaviors (including barriers) on people's knowledge and misconceptions about pandemic influenza A(H1N1) (pH1N1) and adoption of prevention behaviors. The data for this study came from a survey of 1,569 respondents drawn from a nationally representative sample of American adults during pH1N1. We conducted logistic regression analyses when appropriate. We found that (1) SES has a significant association with barriers to information access and processing, levels of pH1N1-related knowledge, and misconceptions; (2) levels of pH1N1-related knowledge are associated positively with the adoption of recommended prevention measures and negatively with the adoption of incorrect protective behaviors; and (3) people with higher SES, higher news exposure, and higher levels of pH1N1-related knowledge, as well as those who actively seek information, are less likely than their counterparts to adopt incorrect prevention behaviors. Strategic public health communication efforts in public health preparedness and during emergencies should take into account potential communication inequalities and develop campaigns that reach across different social groups.

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

    Science.gov (United States)

    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.

  13. Does Glycosylation as a modifier of Original Antigenic Sin explain the case age distribution and unusual toxicity in pandemic novel H1N1 influenza?

    Directory of Open Access Journals (Sweden)

    Nishiura Hiroshi

    2010-01-01

    Full Text Available Abstract Background A pandemic novel H1N1 swine-origin influenza virus has emerged. Most recently the World Health Organization has announced that in a country-dependent fashion, up to 15% of cases may require hospitalization, often including respiratory support. It is now clear that healthy children and young adults are disproportionately affected, most unusually among those with severe respiratory disease without underlying conditions. One possible explanation for this case age distribution is the doctrine of Original Antigenic Sin, i.e., novel H1N1 may be antigenically similar to H1N1 viruses that circulated at an earlier time. Persons whose first exposure to influenza viruses was to such similar viruses would be relatively immune. However, this principle is not sufficient to explain the graded susceptibility between ages 20 and 60, the reduced susceptibility in children below age 10, and the unusual toxicity observed. Methods We collected case data from 11 countries, about 60% of all cases reported through mid-July 2009. We compared sequence data for the hemagglutinin of novel H1N1 with sequences of H1N1 viruses from 1918 to the present. We searched for sequence differences that imply loss of antigenicity either directly through amino acid substitution or by the appearance of sites for potential glycosylation proximal to sites known to be antigenic in humans. We also considered T-cell epitopes. Results In our composite, over 75% of confirmed cases of novel H1N1 occurred in persons ≤ 30 years old, with peak incidence in the age range 10-19 years. Less than 3% of cases occurred in persons over 65, with a gradation in incidence between ages 20 and 60 years. The sequence data indicates that novel H1N1 is most similar to H1N1 viruses that circulated before 1943. Novel H1N1 lacks glycosylation sites on the globular head of hemagglutinin (HA1 near antigenic regions, a pattern shared with the 1918 pandemic strain and H1N1 viruses that circulated

  14. Morbid obesity as a risk factor for hospitalization and death due to 2009 pandemic influenza A(H1N1 disease.

    Directory of Open Access Journals (Sweden)

    Oliver W Morgan

    Full Text Available BACKGROUND: Severe illness due to 2009 pandemic A(H1N1 infection has been reported among persons who are obese or morbidly obese. We assessed whether obesity is a risk factor for hospitalization and death due to 2009 pandemic influenza A(H1N1, independent of chronic medical conditions considered by the Advisory Committee on Immunization Practices (ACIP to increase the risk of influenza-related complications. METHODOLOGY/PRINCIPAL FINDINGS: We used a case-cohort design to compare cases of hospitalizations and deaths from 2009 pandemic A(H1N1 influenza occurring between April-July, 2009, with a cohort of the U.S. population estimated from the 2003-2006 National Health and Nutrition Examination Survey (NHANES; pregnant women and children or=20 year olds, hospitalization was associated with being morbidly obese (BMI>or=40 for individuals with ACIP-recognized chronic conditions (OR = 4.9, 95% CI 2.4-9.9 and without ACIP-recognized chronic conditions (OR = 4.7, 95%CI 1.3-17.2. Among 2-19 year olds, hospitalization was associated with being underweight (BMIor=20 years without ACIP-recognized chronic medical conditions death was associated with obesity (OR = 3.1, 95%CI: 1.5-6.6 and morbid obesity (OR = 7.6, 95%CI 2.1-27.9. CONCLUSIONS/SIGNIFICANCE: Our findings support observations that morbid obesity may be associated with hospitalization and possibly death due to 2009 pandemic H1N1 infection. These complications could be prevented by early antiviral therapy and vaccination.

  15. Clinical and microbiological evaluation of travel-associated respiratory tract infections in travelers returning from countries affected by pandemic A(H1N1) 2009 influenza.

    Science.gov (United States)

    Jauréguiberry, Stéphane; Boutolleau, David; Grandsire, Eric; Kofman, Tomek; Deback, Claire; Aït-Arkoub, Zaïna; Bricaire, François; Agut, Henri; Caumes, Eric

    2012-01-01

    Although acute respiratory tract infections (RTI) have been recognized as a significant cause of illness in returning travelers, few studies have specifically evaluated the etiologies of RTI in this population. This prospective investigation evaluated travelers returning from countries with endemic influenza A(H1N1) 2009, and who were seen in our department at the onset of the outbreak (April-July 2009). Patients were included if they presented with signs of RTI that occurred during travel or less than 7 days after return from overseas travel. Patients were evaluated for microbial agents with RespiFinder plus assay, and throat culture according to clinical presentation. A total of 113 travelers (M/F ratio 1.2:1; mean age 39 y) were included. They were mainly tourists (n = 50; 44.2%) mostly returning from North America (n = 65; 58%) and Mexico (n = 21; 18.5%). The median duration of travel was 23 days (range 2-540 d). The median lag time between return and onset of illness was 0.2 days (range 10 d prior to 7 d after). The main clinical presentation of RTI was influenza-like illness (n = 76; 67.3%). Among the 99 microbiologically evaluated patients, a pathogen was found by polymerase chain reaction (PCR) or throat culture in 65 patients (65.6%). The main etiological agents were influenza A(H1N1) 2009 (18%), influenza viruses (14%), and rhinovirus (20%). A univariate analysis was unable to show variables associated with influenza A(H1N1) 2009, whereas rhinorrhea was associated with viruses other than influenza (p = 0.04). Despite the A(H1N1) 2009 influenza pandemic, rhinovirus and other influenza viruses were also frequent causes of RTI in overseas travelers. Real-time reverse transcription-PCR and nasopharyngeal swab cultures are useful diagnostic tools for evaluating travelers with RTI. © 2011 International Society of Travel Medicine.

  16. Antibody Persistence in Adults Two Years after Vaccination with an H1N1 2009 Pandemic Influenza Virus-Like Particle Vaccine.

    Directory of Open Access Journals (Sweden)

    Nuriban Valero-Pacheco

    Full Text Available The influenza virus is a human pathogen that causes epidemics every year, as well as potential pandemic outbreaks, as occurred in 2009. Vaccination has proven to be sufficient in the prevention and containment of viral spreading. In addition to the current egg-based vaccines, new and promising vaccine platforms, such as cell culture-derived vaccines that include virus-like particles (VLPs, have been developed. VLPs have been shown to be both safe and immunogenic against influenza infections. Although antibody persistence has been studied in traditional egg-based influenza vaccines, studies on antibody response durations induced by VLP influenza vaccines in humans are scarce. Here, we show that subjects vaccinated with an insect cell-derived VLP vaccine, in the midst of the 2009 H1N1 influenza pandemic outbreak in Mexico City, showed antibody persistence up to 24 months post-vaccination. Additionally, we found that subjects that reported being revaccinated with a subsequent inactivated influenza virus vaccine showed higher antibody titres to the pandemic influenza virus than those who were not revaccinated. These findings provide insights into the duration of the antibody responses elicited by an insect cell-derived pandemic influenza VLP vaccine and the possible effects of subsequent influenza vaccination on antibody persistence induced by this VLP vaccine in humans.

  17. 2009 Pandemic Influenza A Virus Subtype H1N1 in Morocco, 2009–2010: Epidemiology, Transmissibility, and Factors Associated With Fatal Cases

    Science.gov (United States)

    Barakat, Amal; Ihazmad, Hassan; El Falaki, Fatima; Tempia, Stefano; Cherkaoui, Imad; El Aouad, Rajae

    2012-01-01

    Background. Following the emergence of 2009 pandemic influenza A virus subtype H1N1 (A[H1N1]pdm09) in the United States and Mexico in April 2009, A(H1N1)pdm09 spread rapidly all over the world. There is a dearth of information about the epidemiology of A(H1N1)pdm09 in Africa, including Morocco. We describe the epidemiologic characteristics of the A(H1N1)pdm09 epidemic in Morocco during 2009–2010, including transmissibility and risk factors associated with fatal disease. Methods. We implemented influenza surveillance for patients presenting with influenza-like illness (ILI) at 136 private and public clinics for patients with severe acute respiratory illness (SARI) at 16 regional public hospitals from June 2009 through February 2010. Respiratory samples and structured questionnaires were collected from all enrolled patients, and samples were tested by real-time reverse-transcription polymerase chain reaction for influenza viruses. We estimated the risk factors associated with fatal disease as well as the basic reproduction number (R0) and the serial interval of the pandemic virus. Results. From June 2009 through February 2010, we obtained 3937 specimens, of which 1452 tested positive for influenza virus. Of these, 1398 (96%) were A(H1N1)pdm09. Forty percent of specimens from ILI cases (1056 of 2646) and 27% from SARI cases (342 of 1291) were positive for A(H1N1)pdm09. Sixty-four deaths occurred among laboratory-confirmed A(H1N1)pdm09 SARI cases. Among these cases, those who had hypertension (age-adjusted odd ratio [aOR], 28.2; 95% confidence interval [CI], 2.0–398.7), had neurological disorders (aOR, 7.5; 95% CI, 1.5–36.4), or were obese (aOR, 7.1; 95% CI, 1.6–31.1), as well as women of gestational age who were pregnant (aOR, 2.5; 95% CI, 1.1–5.6), were at increased risk of death. Across the country, elevated numbers of locally acquired infections were detected 4 months after the detection of the first laboratory-confirmed case and coincided with the

  18. Perceptions and behaviors related to hand hygiene for the prevention of H1N1 influenza transmission among Korean university students during the peak pandemic period

    Directory of Open Access Journals (Sweden)

    Kim Seon-Ung

    2010-07-01

    Full Text Available Abstract Background This study was performed to better assess the perceptions, motivating factors, and behaviors associated with the use of hand washing to prevent H1N1 influenza transmission during the peak pandemic period in Korea. Methods A cross-sectional survey questionnaire was completed by 942 students at a university campus in Suwon, Korea, between December 1 and 8, 2009. The survey included questions regarding individual perceptions, motivating factors, and behaviors associated with hand washing for the prevention of H1N1 influenza transmission. Results Compared to one year prior, 30.3% of participants reported increasing their hand washing frequency. Female students were more likely to practice more frequent hand washing. Women also perceived the effectiveness of hand washing to be lower, and illness severity and personal susceptibility to H1N1 infection to be higher. Study participants who were female (OR: 1.79-3.90 who perceived of hand washing to be effective (OR: 1.34-12.15 and illness severity to be greater (OR: 1.00-3.12 washed their hands more frequently. Conclusions Korean students increased their frequency of hand hygiene practices during the pandemic, with significant gender differences existing in the attitudes and behaviors related to the use of hand hygiene as a means of disease prevention. Here, the factors that affected hand washing behavior were similar to those identified at the beginning of the H1N1 or SARS pandemics, suggesting that public education campaigns regarding hand hygiene are effective in altering individual hand hygiene habits during the peak periods of influenza transmission.

  19. Perception of the A/H1N1 influenza pandemic and acceptance of influenza vaccination by Université Claude Bernard Lyon 1 staff: A descriptive study.

    Science.gov (United States)

    Amour, Sélilah; Djhehiche, Khaled; Zamora, Adeline; Bergeret, Alain; Vanhems, Philippe

    2015-01-01

    We assessed the perception and attitudes of university staff, including medical school and other science specialties, toward the 2009 A/H1N1 influenza pandemic and influenza vaccination program. A cross-sectional online survey was conducted among 4,529 university personnel on October 19-20, 2009. Seven hundred (15%) employees participated in the study. Only 18% were willing to be vaccinated, men more than women (29% versus 9%, P < 0.001), and professors/researchers more than administrative/technical staff (30% vs. 6%, P < 0.001). Intention to be vaccinated was insufficient. Additional efforts are needed to improve information dissemination among university staff. Medical university personnel should receive more information to increase vaccine coverage and protect them as well as patients.

  20. Design and performance of the CDC real-time reverse transcriptase PCR swine flu panel for detection of 2009 A (H1N1) pandemic influenza virus.

    Science.gov (United States)

    Shu, Bo; Wu, Kai-Hui; Emery, Shannon; Villanueva, Julie; Johnson, Roy; Guthrie, Erica; Berman, LaShondra; Warnes, Christine; Barnes, Nathelia; Klimov, Alexander; Lindstrom, Stephen

    2011-07-01

    Swine influenza viruses (SIV) have been shown to sporadically infect humans and are infrequently identified by the Influenza Division of the Centers for Disease Control and Prevention (CDC) after being received as unsubtypeable influenza A virus samples. Real-time reverse transcriptase PCR (rRT-PCR) procedures for detection and characterization of North American lineage (N. Am) SIV were developed and implemented at CDC for rapid identification of specimens from cases of suspected infections with SIV. These procedures were utilized in April 2009 for detection of human cases of 2009 A (H1N1) pandemic (pdm) influenza virus infection. Based on genetic sequence data derived from the first two viruses investigated, the previously developed rRT-PCR procedures were optimized to create the CDC rRT-PCR Swine Flu Panel for detection of the 2009 A (H1N1) pdm influenza virus. The analytical sensitivity of the CDC rRT-PCR Swine Flu Panel was shown to be 5 copies of RNA per reaction and 10(-1.3 - -0.7) 50% infectious doses (ID(50)) per reaction for cultured viruses. Cross-reactivity was not observed when testing human clinical specimens or cultured viruses that were positive for human seasonal A (H1N1, H3N2) and B influenza viruses. The CDC rRT-PCR Swine Flu Panel was distributed to public health laboratories in the United States and internationally from April 2009 until June 2010. The CDC rRT-PCR Swine Flu Panel served as an effective tool for timely and specific detection of 2009 A (H1N1) pdm influenza viruses and facilitated subsequent public health response implementation.

  1. Pandemic H1N1 influenza isolated from free-ranging Northern Elephant Seals in 2010 off the central California coast.

    Directory of Open Access Journals (Sweden)

    Tracey Goldstein

    Full Text Available Interspecies transmission of influenza A is an important factor in the evolution and ecology of influenza viruses. Marine mammals are in contact with a number of influenza reservoirs, including aquatic birds and humans, and this may facilitate transmission among avian and mammalian hosts. Virus isolation, whole genome sequencing, and hemagluttination inhibition assay confirmed that exposure to pandemic H1N1 influenza virus occurred among free-ranging Northern Elephant Seals (Mirounga angustirostris in 2010. Nasal swabs were collected from 42 adult female seals in April 2010, just after the animals had returned to the central California coast from their short post-breeding migration in the northeast Pacific. Swabs from two seals tested positive by RT-PCR for the matrix gene, and virus was isolated from each by inoculation into embryonic chicken eggs. Whole genome sequencing revealed greater than 99% homology with A/California/04/2009 (H1N1 that emerged in humans from swine in 2009. Analysis of more than 300 serum samples showed that samples collected early in 2010 (n = 100 were negative and by April animals began to test positive for antibodies against the pH1N1 virus (HI titer of ≥1∶40, supporting the molecular findings. In vitro characterizations studies revealed that viral replication was indistinguishable from that of reference strains of pH1N1 in canine kidney cells, but replication was inefficient in human epithelial respiratory cells, indicating these isolates may be elephant seal adapted viruses. Thus findings confirmed that exposure to pandemic H1N1 that was circulating in people in 2009 occurred among free-ranging Northern Elephant Seals in 2010 off the central California coast. This is the first report of pH1N1 (A/Elephant seal/California/1/2010 in any marine mammal and provides evidence for cross species transmission of influenza viruses in free-ranging wildlife and movement of influenza viruses between humans and wildlife.

  2. Temporal trends of influenza A (H1N1 virus seroprevalence following 2009 pandemic wave in Guangdong, China: three cross-sectional serology surveys.

    Directory of Open Access Journals (Sweden)

    Fen Yang

    Full Text Available BACKGROUND: To evaluate the temporal trends of seroprevalence to pH1N1 among the Guangdong population following 2009 H1N1 pandemic wave, we conducted three cross-sectional serology surveys in 2010. METHODOLOGY/PRINCIPAL FINDINGS: Three surveys were carried out consecutively in 2010 from January 8 to January 24, from March 15 to April 10 and from August 23 to September 4. Sample populations comprising of 4725, 4727, and 4721 subjects respectively were randomly selected for study in these three surveys. The level of antibodies against pH1N1 was evaluated by hemagglutination inhibition assay. In survey 1, the seroprevalence of pH1N1 among all the subjects is 25.1%, declining to 18.4% in survey 2 and increasing to 21.4% in survey 3. Among vaccinated subjects, the seroprevalence was 49.0%, 53.0%, and 49.4% in the three consecutive surveys, showing no significant differences. In contrast, among non-vaccinated subjects, the seroprevalence declined significantly from 22.8% (survey 1 to 14.3% (survey 2 and subsequently increased to 18.1% (survey 3. The multivariate logistic regression analysis revealed that seroprevalence to pH1N1 in non-vaccinated individuals correlated with the investigated order of the surveys, age, and region (all P<0.05. However, it was not correlated with gender (P = 0.650, seasonal influenza vaccination history (P = 0.402 and symptoms (P = 0.074. CONCLUSIONS/SIGNIFICANCE: In Guangdong, the seroprevalance to pH1N1 decreased initially and then rebounded modestly during the first 9 months following the 2009 pandemic wave. Our results suggest that the prevalence of pH1N1 is still correlated with age and population density during the post-pandemic period. An early end to the free pH1N1 vaccination program might be another important reason for the slight rebound in seroprevalance. Our study findings can help the Guangdong authorities to make evidence-based decisions about a long-term vaccination strategy and boost immunity in specific

  3. Assessing Healthcare Utilization for Influenza-like Illness at an Emergency Department and a Student Health Service during the 2009–2010 H1N1 Pandemic

    Directory of Open Access Journals (Sweden)

    Ruchi Bhandari

    2013-01-01

    Full Text Available Estimates of healthcare utilization during an influenza pandemic are needed in order to plan for the allocation of staff and resources. The aim of this study was to assess the number, age, and arrival time of patients with influenza-like-illness (ILI, and associations between their symptoms during the 2009–2010 H1N1 pandemic. We conducted a cross-sectional analysis of electronic health records from the student health service (SHS and an emergency department (ED in Morgantown, West Virginia, between January 2009 and December 2010. During the 2009–2010 H1N1 pandemic, patient arrivals at SHS and ED varied over the week. SHS patients arrived early in the week and primarily in the afternoon. ED patient arrivals were more evenly distributed, with busier evenings and weekends. Those with fever were more likely to experience cough, sore throat, vomiting/nausea, chills, congestion, headache, and body-ache. These results can assist health professionals in preparing for an influenza pandemic.

  4. Análisis descriptivo de las primeras muertes por influenza pandémica (H1N1 2009 en Colombia Descriptive analysis of the first deaths for pandemic influenza (H1N1 2009 in Colombia

    Directory of Open Access Journals (Sweden)

    Gloria Janneth Rey-Benito

    2009-12-01

    Full Text Available Objetivo: Describir las características demográficas, clínicas y epidemiológicas de los pacientes que han fallecido por la nueva gripe pandémica (A H1N1 2009 en Colombia hasta el 30 de julio de 2009. Materiales y métodos: Éste es un estudio descriptivo. La fuente de información primaria fue el Sistema Nacional de Vigilancia en Salud Pública. Las muestras respiratorias se recolectaron por medio de hisopado faríngeo y se analizaron con pruebas de PCR específicas (rRT-PCR o secuenciación genética. En algunos casos fatales, se requirieron muestras de tejido pulmonar, traqueal o bronquial para confirmar el diagnóstico. Las variables cualitativas se resumen con proporciones y las cuantitativas, con medias aritméticas. Resultados: Hasta el 30 de julio, se habían presentado 16 muertes confirmadas por laboratorio, en pacientes infectados con el nuevo virus pandémico. De éstas, 9 eran mujeres y 15 estaban hospitalizados. El lugar de residencia más frecuente de los casos fatales era Bogotá y la edad media al fallecimiento era de 28,1 años. La dificultad respiratoria, la fiebre y la tos fueron síntomas presentes en todos los pacientes. Una mujer de 27 años estaba embarazada. Conclusiones: Los hallazgos en los pacientes colombianos fallecidos son similares a lo informado en otros países. Se necesitan nuevos estudios para reconocer los factores que incrementan el riesgo de fallecer por esta enfermedad en nuestro país.Objective: To describe the demographic, clinical and epidemiologic characteristics of fatal cases in pandemic influenza A(H1N1 patients reported in Colombia by July 30, 2009. Materials and methods: This is a descriptive study. The primary source of information was the National System of Public Health Surveillance(SIVIGILA. Respiratory samples were gathered using throat swabs and analyzed with PCR specific tests (rRT-PCR or genetic sequencing. In some of the fatal cases, lung, trachea and bronchia tissue samples were

  5. Prevalence of Influenza A (H1N1) Sero positivity in Unvaccinated Health care Workers in Scotland at the Height of the Global Pandemic

    International Nuclear Information System (INIS)

    Smith, K.; Katikireddi, S.V.; Mackenzie, D.G.; Warner, P.; Williams, L.J.; Adamson, W.E.; Carman, W.F.; Dewart, P.; Templeton, K.; Denison, F.C.

    2011-01-01

    Background. We set out to identify the level of previous exposure to influenza A (H1N1) in unvaccinated health care workers (HCWs) at the peak of the pandemic outbreak in the UK, with control samples collected prior to the outbreak. Methods. Cross-sectional study (sero prevalence assessed before and at pandemic peak, with questionnaire data collected at peak of outbreak) in HCWs in Scotland. Results. The prevalence of sero positivity in 493 HCWs at pandemic peak was 10.3%, which was higher than the pre pandemic level by 3.7 percentage points (95% CI 0.3% to 7.3%, P=0.048). Sero positivity rates for front line and non front line HCWs were similar. Conclusion. At pandemic peak, only 10.3% of HCWs were seropositive for influenza A (H1N1), so the great majority were still susceptible to infection at the introduction of the vaccination programme. Few studies have reported on sero prevalence in unvaccinated and asymptomatic participants, so our findings may have relevance to the wider population

  6. Whole genome characterization of human influenza A(H1N1)pdm09 viruses isolated from Kenya during the 2009 pandemic.

    Science.gov (United States)

    Gachara, George; Symekher, Samuel; Otieno, Michael; Magana, Japheth; Opot, Benjamin; Bulimo, Wallace

    2016-06-01

    An influenza pandemic caused by a novel influenza virus A(H1N1)pdm09 spread worldwide in 2009 and is estimated to have caused between 151,700 and 575,400 deaths globally. While whole genome data on new virus enables a deeper insight in the pathogenesis, epidemiology, and drug sensitivities of the circulating viruses, there are relatively limited complete genetic sequences available for this virus from African countries. We describe herein the full genome analysis of influenza A(H1N1)pdm09 viruses isolated in Kenya between June 2009 and August 2010. A total of 40 influenza A(H1N1)pdm09 viruses isolated during the pandemic were selected. The segments from each isolate were amplified and directly sequenced. The resulting sequences of individual gene segments were concatenated and used for subsequent analysis. These were used to infer phylogenetic relationships and also to reconstruct the time of most recent ancestor, time of introduction into the country, rates of substitution and to estimate a time-resolved phylogeny. The Kenyan complete genome sequences clustered with globally distributed clade 2 and clade 7 sequences but local clade 2 viruses did not circulate beyond the introductory foci while clade 7 viruses disseminated country wide. The time of the most recent common ancestor was estimated between April and June 2009, and distinct clusters circulated during the pandemic. The complete genome had an estimated rate of nucleotide substitution of 4.9×10(-3) substitutions/site/year and greater diversity in surface expressed proteins was observed. We show that two clades of influenza A(H1N1)pdm09 virus were introduced into Kenya from the UK and the pandemic was sustained as a result of importations. Several closely related but distinct clusters co-circulated locally during the peak pandemic phase but only one cluster dominated in the late phase of the pandemic suggesting that it possessed greater adaptability. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Secondary household transmission of 2009 pandemic influenza A (H1N1 virus among an urban and rural population in Kenya, 2009-2010.

    Directory of Open Access Journals (Sweden)

    Clara Y Kim

    Full Text Available BACKGROUND: In Kenya, >1,200 laboratory-confirmed 2009 pandemic influenza A (H1N1 (pH1N1 cases occurred since June 2009. We used population-based infectious disease surveillance (PBIDS data to assess household transmission of pH1N1 in urban Nairobi (Kibera and rural Lwak. METHODS: We defined a pH1N1 patient as laboratory-confirmed pH1N1 infection among PBIDS participants during August 1, 2009-February 5, 2010, in Kibera, or August 1, 2009-January 20, 2010, in Lwak, and a case household as a household with a laboratory-confirmed pH1N1 patient. Community interviewers visited PBIDS-participating households to inquire about illnesses among household members. We randomly selected 4 comparison households per case household matched by number of children aged <5. Comparison households had a household visit 10 days before or after the matched patient symptom onset date. We defined influenza-like illnesses (ILI as self-reported cough or sore throat, and a self-reported fever ≤8 days after the pH1N1 patient's symptom onset in case households and ≤8 days before selected household visit in comparison households. We used the Cochran-Mantel-Haenszel test to compare proportions of ILIs among case and comparison households, and log binomial-model to compare that of Kibera and Lwak. RESULTS: Among household contacts of patients with confirmed pH1N1 in Kibera, 4.6% had ILI compared with 8.2% in Lwak (risk ratio [RR], 0.5; 95% confidence interval [CI], 0.3-0.9. Household contacts of patients were more likely to have ILIs than comparison-household members in both Kibera (RR, 1.8; 95% CI, 1.1-2.8 and Lwak (RR, 2.6; 95% CI, 1.6-4.3. Overall, ILI was not associated with patient age. However, ILI rates among household contacts were higher among children aged <5 years than persons aged ≥5 years in Lwak, but not Kibera. CONCLUSIONS: Substantial pH1N1 household transmission occurred in urban and rural Kenya. Household transmission rates were higher in the rural area.

  8. Knowledge, attitudes, and practices of nonpharmaceutical interventions following school dismissals during the 2009 Influenza A H1N1 pandemic in Michigan, United States.

    Directory of Open Access Journals (Sweden)

    Jianrong Shi

    Full Text Available BACKGROUND: Many schools throughout the United States reported an increase in dismissals due to the 2009 influenza A H1N1 pandemic (pH1N1. During the fall months of 2009, more than 567 school dismissals were reported from the state of Michigan. In December 2009, the Michigan Department of Community Health, in collaboration with the United States Centers for Disease Control and Prevention, conducted a survey to describe the knowledge, attitudes, and practices (KAPs of households with school-aged children and classroom teachers regarding the recommended use of nonpharmaceutical interventions (NPIs to slow the spread of influenza. METHODS: A random sample of eight elementary schools (kindergarten through 5th grade was selected from each of the eight public health preparedness regions in the state. Within each selected school, a single classroom was randomly identified from each grade (K-5, and household caregivers of the classroom students and their respective teachers were asked to participate in the survey. RESULTS: In total, 26% (2,188/8,280 of household caregivers and 45% (163/360 of teachers from 48 schools (of the 64 sampled responded to the survey. Of the 48 participating schools, 27% (13 experienced a school dismissal during the 2009 fall term. Eighty-seven percent (1,806/2,082 of caregivers and 80% (122/152 of teachers thought that the 2009 influenza A H1N1 pandemic was severe, and >90% of both groups indicated that they told their children/students to use NPIs, such as washing hands more often and covering coughs with tissues, to prevent infection with influenza. CONCLUSIONS: Knowledge and instruction on the use of NPIs appeared to be high among household caregivers and teachers responding to the survey. Nevertheless, public health officials should continue to explain the public health rationale for NPIs to reduce pandemic influenza. Ensuring this information is communicated to household caregivers and teachers through trusted sources is

  9. Estimating the disease burden of 2009 pandemic influenza A(H1N1 from surveillance and household surveys in Greece.

    Directory of Open Access Journals (Sweden)

    Vana Sypsa

    Full Text Available The aim of this study was to assess the disease burden of the 2009 pandemic influenza A(H1N1 in Greece.Data on influenza-like illness (ILI, collected through cross-sectional nationwide telephone surveys of 1,000 households in Greece repeated for 25 consecutive weeks, were combined with data from H1N1 virologic surveillance to estimate the incidence and the clinical attack rate (CAR of influenza A(H1N1. Alternative definitions of ILI (cough or sore throat and fever>38°C [ILI-38] or fever 37.1-38°C [ILI-37] were used to estimate the number of symptomatic infections. The infection attack rate (IAR was approximated using estimates from published studies on the frequency of fever in infected individuals. Data on H1N1 morbidity and mortality were used to estimate ICU admission and case fatality (CFR rates. The epidemic peaked on week 48/2009 with approximately 750-1,500 new cases/100,000 population per week, depending on ILI-38 or ILI-37 case definition, respectively. By week 6/2010, 7.1%-15.6% of the population in Greece was estimated to be symptomatically infected with H1N1. Children 5-19 years represented the most affected population group (CAR:27%-54%, whereas individuals older than 64 years were the least affected (CAR:0.6%-2.2%. The IAR (95% CI of influenza A(H1N1 was estimated to be 19.7% (13.3%, 26.1%. Per 1,000 symptomatic cases, based on ILI-38 case definition, 416 attended health services, 108 visited hospital emergency departments and 15 were admitted to hospitals. ICU admission rate and CFR were 37 and 17.5 per 100,000 symptomatic cases or 13.4 and 6.3 per 100,000 infections, respectively.Influenza A(H1N1 infected one fifth and caused symptomatic infection in up to 15% of the Greek population. Although individuals older than 65 years were the least affected age group in terms of attack rate, they had 55 and 185 times higher risk of ICU admission and CFR, respectively.

  10. Identification of TMPRSS2 as a Susceptibility Gene for Severe 2009 Pandemic A(H1N1) Influenza and A(H7N9) Influenza

    NARCIS (Netherlands)

    Cheng, Zhongshan; Zhou, Jie; To, Kelvin Kai-Wang; Chu, Hin; Li, Cun; Wang, Dong; Yang, Dong; Zheng, Shufa; Hao, Ke; Bosse, Yohan; Obeidat, Ma'en; Brandsma, Corry-Anke; Song, You-Qiang; Chen, Yu; Zheng, Bo-Jian; Li, Lanjuan; Yuen, Kwok-Yung

    2015-01-01

    The genetic predisposition to severe A(H1N1) 2009 (A[H1N1]pdm09) influenza was evaluated in 409 patients, including 162 cases with severe infection and 247 controls with mild infection. We prioritized candidate variants based on the result of a pilot genome-wide association study and a lung

  11. Association between the 2008-09 seasonal influenza vaccine and pandemic H1N1 illness during Spring-Summer 2009: four observational studies from Canada.

    Directory of Open Access Journals (Sweden)

    Danuta M Skowronski

    2010-04-01

    Full Text Available In late spring 2009, concern was raised in Canada that prior vaccination with the 2008-09 trivalent inactivated influenza vaccine (TIV was associated with increased risk of pandemic influenza A (H1N1 (pH1N1 illness. Several epidemiologic investigations were conducted through the summer to assess this putative association.(1 test-negative case-control design based on Canada's sentinel vaccine effectiveness monitoring system in British Columbia, Alberta, Ontario, and Quebec; (2 conventional case-control design using population controls in Quebec; (3 test-negative case-control design in Ontario; and (4 prospective household transmission (cohort study in Quebec. Logistic regression was used to estimate odds ratios for TIV effect on community- or hospital-based laboratory-confirmed seasonal or pH1N1 influenza cases compared to controls with restriction, stratification, and adjustment for covariates including combinations of age, sex, comorbidity, timeliness of medical visit, prior physician visits, and/or health care worker (HCW status. For the prospective study risk ratios were computed. Based on the sentinel study of 672 cases and 857 controls, 2008-09 TIV was associated with statistically significant protection against seasonal influenza (odds ratio 0.44, 95% CI 0.33-0.59. In contrast, estimates from the sentinel and three other observational studies, involving a total of 1,226 laboratory-confirmed pH1N1 cases and 1,505 controls, indicated that prior receipt of 2008-09 TIV was associated with increased risk of medically attended pH1N1 illness during the spring-summer 2009, with estimated risk or odds ratios ranging from 1.4 to 2.5. Risk of pH1N1 hospitalization was not further increased among vaccinated people when comparing hospitalized to community cases.Prior receipt of 2008-09 TIV was associated with increased risk of medically attended pH1N1 illness during the spring-summer 2009 in Canada. The occurrence of bias (selection, information or

  12. Use of nonpharmaceutical interventions to reduce transmission of 2009 pandemic influenza A (pH1N1) in Pennsylvania public schools.

    Science.gov (United States)

    Miller, Jeffrey R; Short, Vanessa L; Wu, Henry M; Waller, Kirsten; Mead, Paul; Kahn, Emily; Bahn, Beth A; Dale, Jon W; Nasrullah, Muazzam; Walton, Sabrina E; Urdaneta, Veronica; Ostroff, Stephen; Averhoff, Francisco

    2013-04-01

    School-based recommendations for nonpharmaceutical interventions (NPIs) were issued in response to the threat of 2009 pandemic influenza A (pH1N1). The implementation and effectiveness of these recommendations has not been assessed. In November 2009, a Web-based survey of all Pennsylvania public schools was conducted to assess the use of recommended NPIs. Overall, 1040 (31%) of 3351 schools participated in the survey. By fall 2009, 820 (84%) of 979 respondents reported that their school had an influenza plan in place, a 44% higher proportion than in the spring 2009 (p schools communicated health messages (eg, staying home when sick), implemented return to school requirements, and made hand sanitizer available. Schools with a spring influenza plan (N = 568) were less likely to report substantial influenza-like illness (ILI) during the fall wave of influenza than the 299 schools without a spring influenza plan (63% vs 71%, p = .02). This association persisted after controlling for schools with substantial ILI in the spring. The reported use of NPIs in participating Pennsylvania public schools improved substantially from spring to fall and was generally consistent with issued recommendations. The proactive implementation of a number of NPIs and the early implementation of communication and education initiatives might have cumulatively reduced the impact of pH1N1 in some schools. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  13. Genetic characterization of an adapted pandemic 2009 H1N1 influenza virus that reveals improved replication rates in human lung epithelial cells

    International Nuclear Information System (INIS)

    Wörmann, Xenia; Lesch, Markus; Welke, Robert-William; Okonechnikov, Konstantin; Abdurishid, Mirshat; Sieben, Christian; Geissner, Andreas; Brinkmann, Volker; Kastner, Markus; Karner, Andreas; Zhu, Rong; Hinterdorfer, Peter; Anish, Chakkumkal; Seeberger, Peter H.; Herrmann, Andreas

    2016-01-01

    The 2009 influenza pandemic originated from a swine-origin H1N1 virus, which, although less pathogenic than anticipated, may acquire additional virulence-associated mutations in the future. To estimate the potential risk, we sequentially passaged the isolate A/Hamburg/04/2009 in A549 human lung epithelial cells. After passage 6, we observed a 100-fold increased replication rate. High-throughput sequencing of viral gene segments identified five dominant mutations, whose contribution to the enhanced growth was analyzed by reverse genetics. The increased replication rate was pinpointed to two mutations within the hemagglutinin (HA) gene segment (HA_1 D130E, HA_2 I91L), near the receptor binding site and the stem domain. The adapted virus also replicated more efficiently in mice in vivo. Enhanced replication rate correlated with increased fusion pH of the HA protein and a decrease in receptor affinity. Our data might be relevant for surveillance of pre-pandemic strains and development of high titer cell culture strains for vaccine production. - Highlights: • We observed a spontaneous mutation of a 2009-pandemic H1N1 influenza virus in vitro. • The adaptation led to a 100-fold rise in replication rate in human A549 cells. • Adaptation was caused by two mutations in the HA gene segment. • Adaptation correlates with increased fusion pH and decreased receptor affinity.

  14. Genetic characterization of an adapted pandemic 2009 H1N1 influenza virus that reveals improved replication rates in human lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Wörmann, Xenia [Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin (Germany); Lesch, Markus [Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin (Germany); Steinbeis Innovation gGmbH, Center for Systems Biomedicine, Falkensee (Germany); Welke, Robert-William [Department of Biology, Molecular Biophysics, IRI Life Sciences, Humboldt-Universität zu Berlin (Germany); Okonechnikov, Konstantin; Abdurishid, Mirshat [Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin (Germany); Sieben, Christian [Department of Biology, Molecular Biophysics, IRI Life Sciences, Humboldt-Universität zu Berlin (Germany); Geissner, Andreas [Department for Biomolecular Systems, Max Planck Institute for Colloids and Interfaces, Potsdam (Germany); Institute of Chemistry and Biochemistry, Free University, Berlin (Germany); Brinkmann, Volker [Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin (Germany); Kastner, Markus [Institute for Biophysics, Johannes Kepler University, Linz (Austria); Karner, Andreas [Center for Advanced Bioanalysis GmbH (CBL), Linz (Austria); Zhu, Rong; Hinterdorfer, Peter [Institute for Biophysics, Johannes Kepler University, Linz (Austria); Anish, Chakkumkal [Department for Biomolecular Systems, Max Planck Institute for Colloids and Interfaces, Potsdam (Germany); Seeberger, Peter H. [Department for Biomolecular Systems, Max Planck Institute for Colloids and Interfaces, Potsdam (Germany); Institute of Chemistry and Biochemistry, Free University, Berlin (Germany); Herrmann, Andreas [Department of Biology, Molecular Biophysics, IRI Life Sciences, Humboldt-Universität zu Berlin (Germany); and others

    2016-05-15

    The 2009 influenza pandemic originated from a swine-origin H1N1 virus, which, although less pathogenic than anticipated, may acquire additional virulence-associated mutations in the future. To estimate the potential risk, we sequentially passaged the isolate A/Hamburg/04/2009 in A549 human lung epithelial cells. After passage 6, we observed a 100-fold increased replication rate. High-throughput sequencing of viral gene segments identified five dominant mutations, whose contribution to the enhanced growth was analyzed by reverse genetics. The increased replication rate was pinpointed to two mutations within the hemagglutinin (HA) gene segment (HA{sub 1} D130E, HA{sub 2} I91L), near the receptor binding site and the stem domain. The adapted virus also replicated more efficiently in mice in vivo. Enhanced replication rate correlated with increased fusion pH of the HA protein and a decrease in receptor affinity. Our data might be relevant for surveillance of pre-pandemic strains and development of high titer cell culture strains for vaccine production. - Highlights: • We observed a spontaneous mutation of a 2009-pandemic H1N1 influenza virus in vitro. • The adaptation led to a 100-fold rise in replication rate in human A549 cells. • Adaptation was caused by two mutations in the HA gene segment. • Adaptation correlates with increased fusion pH and decreased receptor affinity.

  15. Guillain-Barré syndrome and adjuvanted pandemic influenza A (H1N1 2009 vaccines: a multinational self-controlled case series in Europe.

    Directory of Open Access Journals (Sweden)

    Silvana Romio

    Full Text Available BACKGROUND: The risk of Guillain-Barré syndrome (GBS following the United States' 1976 swine flu vaccination campaign in the USA led to enhanced active surveillance during the pandemic influenza (A(H1N1pdm09 immunization campaign. This study aimed to estimate the risk of GBS following influenza A(H1N1pdm09 vaccination. METHODS: A self-controlled case series (SCCS analysis was performed in Denmark, Finland, France, Netherlands, Norway, Sweden, and the United Kingdom. Information was collected according to a common protocol and standardised procedures. Cases classified at levels 1-4a of the Brighton Collaboration case definition were included. The risk window was 42 days starting the day after vaccination. Conditional Poisson regression and pooled random effects models estimated adjusted relative incidences (RI. Pseudo likelihood and vaccinated-only methods addressed the potential contraindication for vaccination following GBS. RESULTS: Three hundred and three (303 GBS and Miller Fisher syndrome cases were included. Ninety-nine (99 were exposed to A(H1N1pdm09 vaccination, which was most frequently adjuvanted (Pandemrix and Focetria. The unadjusted pooled RI for A(H1N1pdm09 vaccination and GBS was 3.5 (95% Confidence Interval (CI: 2.2-5.5, based on all countries. This lowered to 2.0 (95% CI: 1.2-3.1 after adjustment for calendartime and to 1.9 (95% CI: 1.1-3.2 when we accounted for contra-indications. In a subset (Netherlands, Norway, and United Kingdom we further adjusted for other confounders and there the RI decreased from 1.7 (adjusted for calendar month to 1.4 (95% CI: 0.7-2.8, which is the main finding. CONCLUSION: This study illustrates the potential of conducting European collaborative vaccine safety studies. The main, fully adjusted analysis, showed that the RI of GBS was not significantly elevated after influenza A(H1N1pdm09 vaccination (RI = 1.4 (95% CI: 0.7-2.8. Based on the upper limits of the pooled estimate we can rule out with

  16. Underreporting of 2009 H1N1 Influenza Cases

    Centers for Disease Control (CDC) Podcasts

    Influenza cases are difficult to track because many people don't go to the doctor or get tested for flu when they're sick. The first months of the 2009 H1N1 influenza pandemic were no different. In this podcast, CDC's Dr. Carrie Reed discusses a study in the December issue of Emerging Infectious Diseases that looked at the actual number of cases reported and estimated the true number of cases when correcting for underreporting.

  17. High frequency chest wall oscillation plus Mechanical In-Exsufflation in Duchenne muscular dystrophy with respiratory complications related to pandemic Influenza A/H1N1

    Directory of Open Access Journals (Sweden)

    G. Crescimanno

    2010-11-01

    Full Text Available Two young boys with Duchenne muscular dystrophy, who had contracted 2009 pandemic influenza A/H1N1 (pH1N1, had been treated with antibiotics and steroids without significant improvement. One of them showed severe scoliosis. After hospitalization chest CT scan revealed extensive pulmonary bilateral segmental atelectasis. Their clinical and radiological findings rapidly improved when a sequential respiratory physiotherapy protocol was adopted that consisted of the application of multiple sessions of high-frequency chest wall oscillations each one followed by mechanically assisted coughing manoeuvres. The protocol was well tolerated, effective, easy to apply and special positioning was not required. Fifteen days after treatment initiation both patients clinically recovered. This treatment can be very helpful for neuromuscular patients, particularly when scoliosis prevents conventional respiratory physiotherapy. Resumo: Duas crianças do sexo masculino com distrofia muscular de Duchenne que contraíram o vírus da gripe pandémica A/H1N1(pH1N1 de 2009 foram tratados com antibióticos e esteróides sem melhoria significativa.Um deles revelou escoliose severa. Depois da hospitalização, um TAC ao peito revelou uma atelectasia pulmonar segmentar bilateral extensa. Os seus resultados clínicos e radiológicos melhoraram rapidamente quando foi adoptado um tratamento de fisioterapia respiratória sequencial, consistente na aplicação de múltiplas sessões de oscilações torácicas de alta frequência, cada uma seguida por exercícios de tosse mecanicamente assistidos. O tratamento foi bem tolerado, eficaz e fácil de aplicar, sendo que não foi necessário um posicionamento especial. Quinze dias depois do início do tratamento, ambos os pacientes se encontravam clinicamente recuperados. Este tratamento pode ser muito útil em pacientes com doenças neuromusculares, particularmente quando a escoliose

  18. High frequency chest wall oscillation plus Mechanical In-Exsufflation in Duchenne muscular dystrophy with respiratory complications related to pandemic Influenza A/H1N1

    Directory of Open Access Journals (Sweden)

    G. Crescimanno

    2010-11-01

    Full Text Available Two young boys with Duchenne muscular dystrophy, who had contracted 2009 pandemic influenza A/H1N1 (pH1N1, had been treated with antibiotics and steroids without significant improvement. One of them showed severe scoliosis. After hospitalization chest CT scan revealed extensive pulmonary bilateral segmental atelectasis. Their clinical and radiological findings rapidly improved when a sequential respiratory physiotherapy protocol was adopted that consisted of the application of multiple sessions of high-frequency chest wall oscillations, each one followed by mechanically assisted coughing manoeuvres. The protocol was well tolerated, effective, easy to apply and special positioning was not required. Fifteen days after treatment initiation both patients clinically recovered. This treatment can be very helpful for neuromuscular patients, particularly when scoliosis prevents conventional respiratory physiotherapy. Resumo: Duas crianças do sexo masculino com distrofia muscular de Duchenne que contraíram o vírus da gripe pandémica A/H1N1(pH1N1 de 2009 foram tratados com antibióticos e esteróides sem melhoria significativa.Um deles revelou escoliose severa. Depois da hospitalização, um TAC ao peito revelou uma atelectasia pulmonar segmentar bilateral extensa. Os seus resultados clínicos e radiológicos melhoraram rapidamente quando foi adoptado um tratamento de fisioterapia respiratória sequencial, consistente na aplicação de múltiplas sessões de oscilações torácicas de alta frequência, cada uma seguida por exercícios de tosse mecanicamente assistidos. O tratamento foi bem tolerado, eficaz e fácil de aplicar, sendo que não foi necessário um posicionamento especial. Quinze dias depois do início do tratamento, ambos os pacientes se encontravam clinicamente recuperados. Este tratamento pode ser muito útil em pacientes com doenças neuromusculares, particularmente quando a escoliose

  19. A pandemic influenza H1N1 live vaccine based on modified vaccinia Ankara is highly immunogenic and protects mice in active and passive immunizations.

    Directory of Open Access Journals (Sweden)

    Annett Hessel

    Full Text Available BACKGROUND: The development of novel influenza vaccines inducing a broad immune response is an important objective. The aim of this study was to evaluate live vaccines which induce both strong humoral and cell-mediated immune responses against the novel human pandemic H1N1 influenza virus, and to show protection in a lethal animal challenge model. METHODOLOGY/PRINCIPAL FINDINGS: For this purpose, the hemagglutinin (HA and neuraminidase (NA genes of the influenza A/California/07/2009 (H1N1 strain (CA/07 were inserted into the replication-deficient modified vaccinia Ankara (MVA virus--a safe poxviral live vector--resulting in MVA-H1-Ca and MVA-N1-Ca vectors. These live vaccines, together with an inactivated whole virus vaccine, were assessed in a lung infection model using immune competent Balb/c mice, and in a lethal challenge model using severe combined immunodeficient (SCID mice after passive serum transfer from immunized mice. Balb/c mice vaccinated with the MVA-H1-Ca virus or the inactivated vaccine were fully protected from lung infection after challenge with the influenza H1N1 wild-type strain, while the neuraminidase virus MVA-N1-Ca induced only partial protection. The live vaccines were already protective after a single dose and induced substantial amounts of neutralizing antibodies and of interferon-gamma-secreting (IFN-gamma CD4- and CD8 T-cells in lungs and spleens. In the lungs, a rapid increase of HA-specific CD4- and CD8 T cells was observed in vaccinated mice shortly after challenge with influenza swine flu virus, which probably contributes to the strong inhibition of pulmonary viral replication observed. In addition, passive transfer of antisera raised in MVA-H1-Ca vaccinated immune-competent mice protected SCID mice from lethal challenge with the CA/07 wild-type virus. CONCLUSIONS/SIGNIFICANCE: The non-replicating MVA-based H1N1 live vaccines induce a broad protective immune response and are promising vaccine candidates for

  20. Clinical features and risk factors for severe and critical pregnant women with 2009 pandemic H1N1 influenza infection in China

    Directory of Open Access Journals (Sweden)

    Zhang Peng-jun

    2012-02-01

    Full Text Available Abstract Background 2009 pandemic H1N1 (pH1N1 influenza posed an increased risk of severe illness among pregnant women. Data on risk factors associated with death of pregnant women and neonates with pH1N1 infections are limited outside of developed countries. Methods Retrospective observational study in 394 severe or critical pregnant women admitted to a hospital with pH1N1 influenza from Sep. 1, 2009 to Dec. 31, 2009. rRT-PCR testing was used to confirm infection. In-hospital mortality was the primary endpoint of this study. Univariable logistic analysis and multivariate logistic regression analysis were used to investigate the potential factors on admission that might be associated with the maternal and neonatal mortality. Results 394 pregnant women were included, 286 were infected with pH1N1 in the third trimester. 351 had pneumonia, and 77 died. A PaO2/FiO2 ≤ 200 (odds ratio (OR, 27.16; 95% confidence interval (CI, 2.64-279.70 and higher BMI (i.e. ≥ 30 on admission (OR, 1.26; 95% CI, 1.09 to 1.47 were independent risk factors for maternal death. Of 211 deliveries, 146 neonates survived. Premature delivery (OR, 4.17; 95% CI, 1.19-14.56 was associated neonatal mortality. Among 186 patients who received mechanical ventilation, 83 patients were treated with non-invasive ventilation (NIV and 38 were successful with NIV. The death rate was lower among patients who initially received NIV than those who were initially intubated (24/83, 28.9% vs 43/87, 49.4%; p = 0.006. Septic shock was an independent risk factor for failure of NIV. Conclusions Severe hypoxemia and higher BMI on admission were associated with adverse outcomes for pregnant women. Preterm delivery was a risk factor for neonatal death among pregnant women with pH1N1 influenza infection. NIV may be useful in selected pregnant women without septic shock.

  1. Molecular findings from influenza A(H1N1pdm09 detected in patients from a Brazilian equatorial region during the pandemic period

    Directory of Open Access Journals (Sweden)

    Maria José Couto Oliveira

    2014-11-01

    Full Text Available After the World Health Organization officially declared the end of the first pandemic of the XXI century in August 2010, the influenza A(H1N1pdm09 virus has been disseminated in the human population. In spite of its sustained circulation, very little on phylogenetic data or oseltamivir (OST resistance is available for the virus in equatorial regions of South America. In order to shed more light on this topic, we analysed the haemagglutinin (HA and neuraminidase (NA genes of influenza A(H1N1pdm09 positive samples collected during the pandemic period in the Pernambuco (PE, a northeastern Brazilian state. Complete HA sequences were compared and amino acid changes were related to clinical outcome. In addition, the H275Y substitution in NA, associated with OST resistance, was investigated by pyrosequencing. Samples from PE were grouped in phylogenetic clades 6 and 7, being clustered together with sequences from South and Southeast Brazil. The D222N/G HA gene mutation, associated with severity, was found in one deceased patient that was pregnant. Additionally, the HA mutation K308E, which appeared in Brazil in 2010 and was only detected worldwide the following year, was identified in samples from hospitalised cases. The resistance marker H275Y was not identified in samples tested. However, broader studies are needed to establish the real frequency of resistance in this Brazilian region.

  2. Evaluating Syndromic surveillance systems at institutions of higher education (IHEs: A retrospective analysis of the 2009 H1N1 influenza pandemic at two universities

    Directory of Open Access Journals (Sweden)

    May Larissa

    2011-07-01

    Full Text Available Abstract Background Syndromic surveillance has been widely adopted as a real-time monitoring tool for timely response to disease outbreaks. During the second wave of the pH1N1 pandemic in Fall 2009, two major universities in Washington, DC collected data that were potentially indicative of influenza-like illness (ILI cases in students and staff. In this study, our objectives were three-fold. The primary goal of this study was to characterize the impact of pH1N1 on the campuses as clearly as possible given the data available and their likely biases. In addition, we sought to evaluate the strengths and weaknesses of the data series themselves, in order to inform these two universities and other institutions of higher education (IHEs about real-time surveillance systems that are likely to provide the most utility in future outbreaks (at least to the extent that it is possible to generalize from this analysis. Methods We collected a wide variety of data that covered both student ILI cases reported to medical and non-medical staff, employee absenteeism, and hygiene supply distribution records (from University A only. Communication data were retrieved from university broadcasts, university preparedness websites, and H1N1-related on campus media reports. Regional data based on the Centers for Disease Control and Prevention Outpatient Influenza-like Illness Surveillance Network (CDC ILINet surveillance network, American College Health Association (ACHA pandemic influenza surveillance data, and local Google Flu Trends were used as external data sets. We employed a "triangulation" approach for data analysis in which multiple contemporary data sources are compared to identify time patterns that are likely to reflect biases as well as those that are more likely to be indicative of actual infection rates. Results Medical personnel observed an early peak at both universities immediately after school began in early September and a second peak in early November

  3. Evaluating syndromic surveillance systems at institutions of higher education (IHEs): a retrospective analysis of the 2009 H1N1 influenza pandemic at two universities.

    Science.gov (United States)

    Zhang, Ying; May, Larissa; Stoto, Michael A

    2011-07-26

    Syndromic surveillance has been widely adopted as a real-time monitoring tool for timely response to disease outbreaks. During the second wave of the pH1N1 pandemic in Fall 2009, two major universities in Washington, DC collected data that were potentially indicative of influenza-like illness (ILI) cases in students and staff. In this study, our objectives were three-fold. The primary goal of this study was to characterize the impact of pH1N1 on the campuses as clearly as possible given the data available and their likely biases. In addition, we sought to evaluate the strengths and weaknesses of the data series themselves, in order to inform these two universities and other institutions of higher education (IHEs) about real-time surveillance systems that are likely to provide the most utility in future outbreaks (at least to the extent that it is possible to generalize from this analysis). We collected a wide variety of data that covered both student ILI cases reported to medical and non-medical staff, employee absenteeism, and hygiene supply distribution records (from University A only). Communication data were retrieved from university broadcasts, university preparedness websites, and H1N1-related on campus media reports. Regional data based on the Centers for Disease Control and Prevention Outpatient Influenza-like Illness Surveillance Network (CDC ILINet) surveillance network, American College Health Association (ACHA) pandemic influenza surveillance data, and local Google Flu Trends were used as external data sets. We employed a "triangulation" approach for data analysis in which multiple contemporary data sources are compared to identify time patterns that are likely to reflect biases as well as those that are more likely to be indicative of actual infection rates. Medical personnel observed an early peak at both universities immediately after school began in early September and a second peak in early November; only the second peak corresponded to patterns in

  4. Safety and immunogenicity of an MF59-adjuvanted A/H1N1 pandemic influenza vaccine in children from three to seventeen years of age.

    Science.gov (United States)

    Knuf, Markus; Leroux-Roels, Geert; Rümke, Hans C; Abarca, Katia; Rivera, Luis; Lattanzi, Maria; Pedotti, Paola; Arora, Ashwani; Kieninger-Baum, Dorothee; Della Cioppa, Giovanni

    2015-01-01

    This study was designed to identify the optimal dose of an MF59-adjuvanted, monovalent, A/H1N1 influenza vaccine in healthy paediatric subjects. Subjects aged 3-8 years (n=194) and 9-17 years (n=160) were randomized to receive two primary doses of A/H1N1 vaccine containing either 3.75 μg antigen with half a standard dose of MF59 adjuvant, 7.5 μg antigen with a full dose of MF59, or (children 3-8 years only), a non-adjuvanted 15 μg formulation. A booster dose of MF59-adjuvanted seasonal influenza vaccine including homologous A/H1N1 strain was given one year after priming. Immunogenicity was assessed by haemagglutination inhibition (HI) and microneutralization assays. Vaccine safety was assessed throughout the study (up to 18 months). A single priming dose of either MF59-adjuvanted formulation was sufficient to meet the European licensure criteria for pandemic influenza vaccines (HI titres ≥1:40>70%; seroconversion>40%; and GMR>2.5). Two non-adjuvanted vaccine doses were required to meet the same licensure criteria. After first and second doses, percentage of subjects with HI titres ≥1:40 were between 97% and 100% in the adjuvanted vaccine groups compared with 68% and 91% in the non-adjuvanted group, respectively. Postvaccination seroconversion rates ranged from 91% to 98% in adjuvanted groups and were 68% (first dose) and 98% (second dose) in the non-adjuvanted group. HI titres ≥1:330 after primary doses were achieved in 69% to 90% in adjuvanted groups compared with 41% in the non-adjuvanted group. Long-term antibody persistence after priming and a robust antibody response to booster immunization were observed in all vaccination groups. All A/H1N1 vaccine formulations were generally well tolerated. No vaccine-related serious adverse events occurred, and no subjects were withdrawn from the study due to an adverse event. An MF59-adjuvanted influenza vaccine containing 3.75 μg of A/H1N1 antigen was well tolerated and sufficiently immunogenic to meet all the

  5. Pulmonary function in patients with pandemic H1N1

    Directory of Open Access Journals (Sweden)

    Soraia Koppe

    Full Text Available Abstract Introduction: The influenza A (H1N1 was responsible for the 2009 pandemic, especially with severe pulmonary complications. Objective: To describe characteristics of patients in a university hospital in Curitiba - PR with laboratory diagnosis of influenza A (H1N1 and its post hospital discharge in the 2009 lung function pandemic. Methodology: A retrospective observational study. It was used as a data source the institution Epidemiology Service (SEPIH and spirometry tests of patients who were admitted in 2009, 18 years without lung disease associated and non-pregnant. Descriptive statistics were used and applied Fisher's exact test for relationship between comorbidity and spirometry tests. Results: There were 84 confirmed cases, of these 11 were eligible for the study with a mean age of 44.27 years (± 9.63 and 63.63% males. 54.54% of the 11 patients had comorbidities associated with systemic arterial hypertension (54.54%, diabetes (18.18% and late postoperative period of kidney transplantation (18.18% were the most frequent. Most patients (81.81% had BMI ≥ 25kg / m². The Spirometry test was performed approximately 40.09 (± 15.27 days after discharge, of these, 5 had restrictive pattern and all had abnormal chest radiograph results. There was no statistically significant difference between the results of Spirometry and comorbidities (p=0.24. Conclusions: The group evaluated in this research did not show a direct relationship between Spirometry and comorbidities, but changes in Spirometry in some patients after hospital discharge stood out, suggesting changes in lung function due to influenza A (H1N1.

  6. Hygiene perception changes during the influenza A H1N1 pandemic in Germany: incorporating the results of two cross-sectional telephone surveys 2008-2009.

    Science.gov (United States)

    Meilicke, Gerald; Riedmann, Klaus; Biederbick, Walter; Müller, Ute; Wierer, Traugott; Bartels, Cornelius

    2013-10-16

    The federal campaign Wir gegen Viren [Us against viruses] promoted hygiene in Germany during the influenza A H1N1 pandemic in 2009. The intervention aimed to encourage people to protect themselves against respiratory infections by simple means of hygiene behaviour. Quantitative research was carried out to outline changes in hygiene perception of the population over time, and to find out whether the potential hygiene perception changes were consistent to the federal campaign about hygiene or not. To determine changes in the hygiene perception of the population, two cross-sectional telephone surveys were held, each one with n = 2006 participants. The initial survey was carried out before the influenza A H1N1 pandemic in calendar week 49-51 in 2008 and the second in week 48 in 2009 directly after the peak of the pandemic in Germany. The questionnaire contained indicators about perceived hand hygiene efficacy, preference for coughing into the sleeve, propensity for presenteeism while showing symptoms of a cold and acceptance of hygiene masks. The proportion of people who perceive the efficacy of hand washing as "very good" increased significantly from 50.9% in 2008 to 61.1% in 2009. The proportion of people who perceive coughing into the sleeve as the best way to cough increased even more dramatically from 4.8% in 2008 to 38.3% in 2009. In contrast the propensity for presenteeism decreased significantly: The proportion of people who state that they always report to work while they show symptoms of a cold decreased from 50.8% in 2008 to 40.9% in 2009. Acceptance of hygiene masks has not changed significantly from 2008 to 2009. The results revealed changes in hygiene perception during influenza A H1N1 pandemic in Germany. The changes we found are in accordance with the hygiene recommendations given by the federal campaign Wir gegen Viren [Us against viruses]. Results can constitute a practical benchmark for future research about hygiene perception and hygiene promotion

  7. The Impact of Pandemic Influenza H1N1 on Health-Related Quality of Life: A Prospective Population-Based Study

    Science.gov (United States)

    van Hoek, Albert Jan; Underwood, Anthony; Jit, Mark; Miller, Elizabeth; Edmunds, W. John

    2011-01-01

    Background While the H1N1v influenza pandemic in 2009 was clinically mild, with a low case-fatality rate, the overall disease burden measured in quality-adjusted life years (QALY) lost has not been estimated. Such a measure would allow comparison with other diseases and assessment of the cost-effectiveness of pandemic control measures. Methods and Findings Cases of H1N1v confirmed by polymerase chain reaction (PCR) and PCR negative cases with similar influenza-like illness (ILI controls) in 7 regions of England were sent two questionnaires, one within a week of symptom onset and one two weeks later, requesting information on duration of illness, work loss and antiviral use together with EQ-5D questionnaires. Results were compared with those for seasonal influenza from a systematic literature review. A total QALY loss for the 2009 pandemic in England was calculated based on the estimated total clinical cases and reported deaths. A total of 655 questionnaires were sent and 296 (45%) returned. Symptoms and average illness duration were similar between confirmed cases and ILI controls (8.8 days and 8.7 days respectively). Days off work were greater for cases than ILI controls (7.3 and 4.9 days respectively, p = 0.003). The quality-adjusted life days lost was 2.92 for confirmed cases and 2.74 for ILI controls, with a reduction in QALY loss after prompt use of antivirals in confirmed cases. The overall QALY loss in the pandemic was estimated at 28,126 QALYs (22,267 discounted) of which 40% was due to deaths (24% with discounting). Conclusion Given the global public health significance of influenza, it is remarkable that no previous prospective study of the QALY loss of influenza using standardised and well validated methods has been performed. Although the QALY loss was minor for individual patients, the estimated total burden of influenza over the pandemic was substantial when compared to other infectious diseases. PMID:21399678

  8. Identification of cross-reacting T-cell epitopes in structural and non-structural proteins of swine and pandemic H1N1 influenza A virus strains in pigs

    DEFF Research Database (Denmark)

    Baratelli, Massimiliano; Pedersen, Lasse Eggers; Trebbien, Ramona

    2017-01-01

    Heterologous protection against swine influenza viruses (SwIVs) of different lineages is an important concern for the pig industry. Cross-protection between 'avian-like' H1N1 and 2009 pandemic H1N1 lineages has been observed previously, indicating the involvement of cross-reacting T-cells. Here...

  9. Profile of Brazilian scientific production on A/H1N1 pandemic influenza Perfil da produção científica brasileira sobre a gripe pandemica de influenza A/H1N1

    Directory of Open Access Journals (Sweden)

    Adriana Luchs

    2012-06-01

    Full Text Available In the last few years, bibliometric studies have proliferated, seeking to provide data on world research. This study analyzes the profile of the Brazilian scientific production in the A (H1N1 influenza field between 2009 and 2011. The research was conducted in MEDLINE, SciELO and LILACS databases, selecting papers in which the term "H1N1" and "Brazil" were defined as the main topics. The data were analyzed taking into consideration the Brazilian state and institution in which the articles were produced, the impact factor of the journal and the language. The research revealed 40 documents (27 from MEDLINE, 16 from SciELO and 24 from LILACS. The journal impact factor ranged from 0.0977 to 8.1230. A similar amount of articles were written in English and Portuguese and São Paulo was the most productive state in the country, with 95% of the Brazilian production originating from the Southern and Southeastern regions. Linguistic data indicate that previous efforts made in order to improve the scientific production of Brazilian researchers making their observations attain a broader scientific audience produced results. It is necessary to assess the scientific studies, especially those conducted with public funds, in order to ensure that the results will benefit society.Nos últimos anos, estudos bibliométricos proliferaram, procurando prover dados sobre a pesquisa mundial. O presente estudo analisou o perfil da produção científica brasileira no campo da influenza A (H1N1 durante o período de 2009 a 2011. A pesquisa foi conduzida através das bases de dados Medline, SciELO e Lilacs, selecionando artigos onde os termos "H1N1" e "Brazil" foram definidos como tópicos principais. Os dados foram analisados considerando-se: o estado brasileiro e a institutição onde o trabalho foi produzido, o fator de impacto de periódico e a língua. A pesquisa revelou 40 documentos (27 provenientes do Medline, 16 do SciELO e 24 do Lilacs. O fator de impacto do peri

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

    Science.gov (United States)

    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.

  11. Protection of pigs against pandemic swine origin H1N1 influenza A virus infection by hemagglutinin- or neuraminidase-expressing attenuated pseudorabies virus recombinants.

    Science.gov (United States)

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

    2015-03-02

    Influenza is an important respiratory disease of pigs, and may lead to novel human pathogens like the 2009 pandemic H1N1 swine-origin influenza virus (SoIV). Therefore, improved influenza vaccines for pigs are required. Recently, we demonstrated that single intranasal immunization with a hemagglutinin (HA)-expressing pseudorabies virus recombinant of vaccine strain Bartha (PrV-Ba) protected pigs from H1N1 SoIV challenge (Klingbeil et al., 2014). Now we investigated enhancement of efficacy by prime-boost vaccination and/or intramuscular administration. Furthermore, a novel PrV-Ba recombinant expressing codon-optimized N1 neuraminidase (NA) was included. In vitro replication of this virus was only slightly affected compared to parental virus. Unlike HA, the abundantly expressed NA was efficiently incorporated into PrV particles. Immunization of pigs with the two PrV recombinants, either singly or in combination, induced B cell proliferation and the expected SoIV-specific antibodies, whose titers increased substantially after boost vaccination. After immunization of animals with either PrV recombinant H1N1 SoIV challenge virus replication was significantly reduced compared to PrV-Ba vaccinated or naïve controls. Protective efficacy of HA-expressing PrV was higher than of NA-expressing PrV, and not significantly enhanced by combination. Despite higher serum antibody titers obtained after intramuscular immunization, transmission of challenge virus to naïve contact animals was only prevented after intranasal prime-boost vaccination with HA-expressing PrV-Ba. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Hemagglutinin 222D/G polymorphism facilitates fast intra-host evolution of pandemic (H1N1 2009 influenza A viruses.

    Directory of Open Access Journals (Sweden)

    Nora Seidel

    Full Text Available The amino acid substitution of aspartic acid to glycine in hemagglutinin (HA in position 222 (HA-D222G as well as HA-222D/G polymorphism of pandemic (H1N1 2009 influenza viruses (A(H1N1pdm09 were frequently reported in severe influenza in humans and mice. Their impact on viral pathogenicity and the course of influenza has been discussed controversially and the underlying mechanism remained unclarified. In the present study, BALB/c mice, infected with the once mouse lung- and cell-passaged A(H1N1pdm09 isolate A/Jena/5258/09 (mpJena/5258, developed severe pneumonia. From day 2 to 3 or 4 post infection (p.i. symptoms (body weight loss and clinical score continuously worsened. After a short disease stagnation or even recovery phase in most mice, severity of disease further increased on days 6 and 7 p.i. Thereafter, surviving mice recovered. A 45 times higher virus titer maximum in the lung than in the trachea on day 2 p.i. and significantly higher tracheal virus titers compared to lung on day 6 p.i. indicated changes in the organ tropism during infection. Sequence analysis revealed an HA-222D/G polymorphism. HA-D222 and HA-G222 variants co-circulated in lung and trachea. Whereas, HA-D222 variant predominated in the lung, HA-G222 became the major variant in the trachea after day 4 p.i. This was accompanied by lower neutralizing antibody titers and broader receptor recognition including terminal sialic acid α-2,3-linked galactose, which is abundant on mouse trachea epithelial cells. Plaque-purified HA-G222-mpJena/5258 virus induced severe influenza with maximum symptom on day 6 p.i. These results demonstrated for the first time that HA-222D/G quasispecies of A(H1N1pdm09 caused severe biphasic influenza because of fast viral intra-host evolution, which enabled partial antibody escape and minor changes in receptor binding.

  13. Safety of pandemic H1N1 vaccines in children and adolescents

    NARCIS (Netherlands)

    E.G. Wijnans (Leonoor); S. de Bie (Sandra); J.P. Dieleman (Jeanne); J. Bonhoeffer (Jan); M.C.J.M. Sturkenboom (Miriam)

    2011-01-01

    textabstractDuring the 2009 influenza A (H1N1) pandemic several pandemic H1N1 vaccines were licensed using fast track procedures, with relatively limited data on the safety in children and adolescents. Different extensive safety monitoring efforts were put in place to ensure timely detection of

  14. Hospitalizations for Pandemic (H1N1) 2009 among Maori and Pacific Islanders, New Zealand

    Science.gov (United States)

    Verrall, Ayesha; Norton, Katherine; Rooker, Serena; Dee, Stephen; Olsen, Leeanne; Tan, Chor Ee; Paull, Sharon; Allen, Richard

    2010-01-01

    Community transmission of influenza A pandemic (H1N1) 2009 was followed by high rates of hospital admissions in the Wellington region of New Zealand, particularly among Maori and Pacific Islanders. These findings may help health authorities anticipate the effects of pandemic (H1N1) 2009 in other communities. PMID:20031050

  15. Pandemic (H1N1 2009 influenza community transmission was established in one Australian state when the virus was first identified in North America.

    Directory of Open Access Journals (Sweden)

    Heath A Kelly

    Full Text Available BACKGROUND: In mid-June 2009 the State of Victoria in Australia appeared to have the highest notification rate of pandemic (H1N1 2009 influenza in the world. We hypothesise that this was because community transmission of pandemic influenza was already well established in Victoria at the time testing for the novel virus commenced. In contrast, this was not true for the pandemic in other parts of Australia, including Western Australia (WA. METHODS: We used data from detailed case follow-up of patients with confirmed infection in Victoria and WA to demonstrate the difference in the pandemic curve in two Australian states on opposite sides of the continent. We modelled the pandemic in both states, using a susceptible-infected-removed model with Bayesian inference accounting for imported cases. RESULTS: Epidemic transmission occurred earlier in Victoria and later in WA. Only 5% of the first 100 Victorian cases were not locally acquired and three of these were brothers in one family. By contrast, 53% of the first 102 cases in WA were associated with importation from Victoria. Using plausible model input data, estimation of the effective reproductive number for the Victorian epidemic required us to invoke an earlier date for commencement of transmission to explain the observed data. This was not required in modelling the epidemic in WA. CONCLUSION: Strong circumstantial evidence, supported by modelling, suggests community transmission of pandemic influenza was well established in Victoria, but not in WA, at the time testing for the novel virus commenced in Australia. The virus is likely to have entered Victoria and already become established around the time it was first identified in the US and Mexico.

  16. Serological response to the 2009 pandemic influenza A (H1N1 virus for disease diagnosis and estimating the infection rate in Thai population.

    Directory of Open Access Journals (Sweden)

    Hatairat Lerdsamran

    Full Text Available BACKGROUND: Individuals infected with the 2009 pandemic virus A(H1N1 developed serological response which can be measured by hemagglutination-inhibition (HI and microneutralization (microNT assays. METHODOLOGY/PRINCIPAL FINDINGS: MicroNT and HI assays for specific antibody to the 2009 pandemic virus were conducted in serum samples collected at the end of the first epidemic wave from various groups of Thai people: laboratory confirmed cases, blood donors and health care workers (HCW in Bangkok and neighboring province, general population in the North and the South, as well as archival sera collected at pre- and post-vaccination from vaccinees who received influenza vaccine of the 2006 season. This study demonstrated that goose erythrocytes yielded comparable HI antibody titer as compared to turkey erythrocytes. In contrast to the standard protocol, our investigation found out the necessity to eliminate nonspecific inhibitor present in the test sera by receptor destroying enzyme (RDE prior to performing microNT assay. The investigation in pre-pandemic serum samples showed that HI antibody was more specific to the 2009 pandemic virus than NT antibody. Based on data from pre-pandemic sera together with those from the laboratory confirmed cases, HI antibody titers ≥ 40 for adults and ≥ 20 for children could be used as the cut-off level to differentiate between the individuals with or without past infection by the 2009 pandemic virus. CONCLUSIONS/SIGNIFICANCE: Based on the cut-off criteria, the infection rates of 7 and 12.8% were estimated in blood donors and HCW, respectively after the first wave of the 2009 influenza pandemic. Among general population, the infection rate of 58.6% was found in children versus 3.1% in adults.

  17. Integrative study of pandemic A/H1N1 influenza infections: design and methods of the CoPanFlu-France cohort

    Directory of Open Access Journals (Sweden)

    Lapidus Nathanael

    2012-06-01

    Full Text Available Abstract Background The risk of influenza infection depends on biological characteristics, individual or collective behaviors and the environmental context. The Cohorts for Pandemic Influenza (CoPanFlu France study was set up in 2009 after the identification of the novel swine-origin A/H1N1 pandemic influenza virus. This cohort of 601 households (1450 subjects representative for the general population aims at using an integrative approach to study the risk and characteristics of influenza infection as a complex combination of data collected from questionnaires regarding sociodemographic, medical, behavioral characteristics of subjects and indoor environment, using biological samples or environmental databases. Methods/Design Households were included between December 2009 and July 2010. The design of this study relies on systematic follow-up visits between influenza seasons and additional visits during influenza seasons, when an influenza-like illness is detected in a household via an active surveillance system. During systematic visits, a nurse collects individual and environmental data on questionnaires and obtains blood samples from all members of the household. When an influenza-like-illness is detected, a nurse visits the household three times during the 12 following days, and collects data on questionnaires regarding exposure and symptoms, and biological samples (including nasal swabs from all subjects in the household. The end of the follow-up period is expected in fall 2012. Discussion The large amount of data collected throughout the follow-up will permit a multidisciplinary study of influenza infections. Additional data is being collected and analyzed in this ongoing cohort. The longitudinal analysis of these households will permit integrative analyses of complex phenomena such as individual, collective and environmental risk factors of infection, routes of transmission, or determinants of the immune response to infection or vaccination.

  18. Distinct T and NK cell populations may serve as immune correlates of protection against symptomatic pandemic influenza A(H1N1 virus infection during pregnancy.

    Directory of Open Access Journals (Sweden)

    Miloje Savic

    Full Text Available Maternal influenza infection during pregnancy is associated with increased risk of morbidity and mortality. However, the link between the anti-influenza immune responses and health-related risks during infection is not well understood. We have analyzed memory T and NK cell mediated immunity (CMI responses in pandemic influenza A(H1N1pdm09 (pdm09 virus infected non-vaccinated pregnant women participating in the Norwegian Influenza Pregnancy Cohort (NorFlu. The cohort includes information on immunization, self-reported health and disease status, and biological samples (plasma and PBMC. Infected cases (N = 75 were defined by having a serum hemagglutination inhibition (HI titer > = 20 to influenza pdm09 virus at the time of delivery, while controls (N = 75 were randomly selected among non-infected pregnant women (HI titer <10. In ELISpot assays cases had higher frequencies of IFNγ+ CD8+ T cells responding to pdm09 virus or conserved CD8 T cell-restricted influenza A virus epitopes, compared to controls. Within this T cell population, frequencies of CD95+ late effector (CD45RA+CCR7- and naive (CD45RA+CCR7+ CD8+ memory T cells correlated inversely with self-reported influenza illness (ILI symptoms. ILI symptoms in infected women were also associated with lower numbers of poly-functional (IFNγ+TNFα+, IL2+IFNγ+, IL2+IFNγ+TNFα+ CD4+ T cells and increased frequencies of IFNγ+CD3-CD7+ NK cells compared to asymptomatic cases, or controls, after stimulation with the pdm09 virus. Taken together, virus specific and functionally distinct T and NK cell populations may serve as cellular immune correlates of clinical outcomes of pandemic influenza disease in pregnant women. Our results may provide information important for future universal influenza vaccine design.

  19. Distinct T and NK cell populations may serve as immune correlates of protection against symptomatic pandemic influenza A(H1N1) virus infection during pregnancy.

    Science.gov (United States)

    Savic, Miloje; Dembinski, Jennifer L; Laake, Ida; Hungnes, Olav; Cox, Rebecca; Oftung, Fredrik; Trogstad, Lill; Mjaaland, Siri

    2017-01-01

    Maternal influenza infection during pregnancy is associated with increased risk of morbidity and mortality. However, the link between the anti-influenza immune responses and health-related risks during infection is not well understood. We have analyzed memory T and NK cell mediated immunity (CMI) responses in pandemic influenza A(H1N1)pdm09 (pdm09) virus infected non-vaccinated pregnant women participating in the Norwegian Influenza Pregnancy Cohort (NorFlu). The cohort includes information on immunization, self-reported health and disease status, and biological samples (plasma and PBMC). Infected cases (N = 75) were defined by having a serum hemagglutination inhibition (HI) titer > = 20 to influenza pdm09 virus at the time of delivery, while controls (N = 75) were randomly selected among non-infected pregnant women (HI titer <10). In ELISpot assays cases had higher frequencies of IFNγ+ CD8+ T cells responding to pdm09 virus or conserved CD8 T cell-restricted influenza A virus epitopes, compared to controls. Within this T cell population, frequencies of CD95+ late effector (CD45RA+CCR7-) and naive (CD45RA+CCR7+) CD8+ memory T cells correlated inversely with self-reported influenza illness (ILI) symptoms. ILI symptoms in infected women were also associated with lower numbers of poly-functional (IFNγ+TNFα+, IL2+IFNγ+, IL2+IFNγ+TNFα+) CD4+ T cells and increased frequencies of IFNγ+CD3-CD7+ NK cells compared to asymptomatic cases, or controls, after stimulation with the pdm09 virus. Taken together, virus specific and functionally distinct T and NK cell populations may serve as cellular immune correlates of clinical outcomes of pandemic influenza disease in pregnant women. Our results may provide information important for future universal influenza vaccine design.

  20. Genome wide analysis of narcolepsy in China implicates novel immune loci and reveals changes in association prior to versus after the 2009 H1N1 influenza pandemic.

    Directory of Open Access Journals (Sweden)

    Fang Han

    2013-10-01

    Full Text Available Previous studies in narcolepsy, an autoimmune disorder affecting hypocretin (orexin neurons and recently associated with H1N1 influenza, have demonstrated significant associations with five loci. Using a well-characterized Chinese cohort, we refined known associations in TRA@ and P2RY11-DNMT1 and identified new associations in the TCR beta (TRB@; rs9648789 max P = 3.7 × 10(-9 OR 0.77, ZNF365 (rs10995245 max P = 1.2 × 10(-11 OR 1.23, and IL10RB-IFNAR1 loci (rs2252931 max P = 2.2 × 10(-9 OR 0.75. Variants in the Human Leukocyte Antigen (HLA- DQ region were associated with age of onset (rs7744020 P = 7.9×10(-9 beta -1.9 years and varied significantly among cases with onset after the 2009 H1N1 influenza pandemic compared to previous years (rs9271117 P = 7.8 × 10(-10 OR 0.57. These reflected an association of DQB1*03:01 with earlier onset and decreased DQB1*06:02 homozygosity following 2009. Our results illustrate how genetic association can change in the presence of new environmental challenges and suggest that the monitoring of genetic architecture over time may help reveal the appearance of novel triggers for autoimmune diseases.

  1. Pandemic influenza (A/H1N1 vaccine uptake among French private general practitioners: a cross sectional study in 2010.

    Directory of Open Access Journals (Sweden)

    Pierre Verger

    Full Text Available BACKGROUND: In July, 2009, French health authorities, like those in many other countries, decided to embark on a mass vaccination campaign against the pandemic A(H1N1 influenza. Private general practitioners (GPs were not involved in this campaign. We studied GPs' pandemic vaccine (pvaccine uptake, quantified the relative contribution of its potential explanatory factors and studied whether their own vaccination choice was correlated with their recommendations to patients about pvaccination. METHODOLOGY/PRINCIPAL FINDINGS: In this cross-sectional telephone survey, professional investigators interviewed an existing panel of randomly selected private GPs (N = 1431; response rate at inclusion in the panel: 36.8%; participation rate in the survey: 100%. The main outcome variable was GPs' own pvaccine uptake. We used an averaging multi-model approach to quantify the relative contribution of factors associated with their vaccination. The pvaccine uptake rate was 61% (95%CI = 58.3-63.3. Four independent factors contributed the most to this rate (partial Nagelkerke's R(2: history of previous vaccination against seasonal influenza (14.5%, perception of risks and efficacy of the pvaccine (10.8%, opinions regarding the organization of the vaccination campaign (7.1%, and perception of the pandemic's severity (5.2%. Overall, 71.3% (95%CI = 69.0-73.6 of the participants recommended pvaccination to young adults at risk and 40.1% (95%CI = 37.6-42.7 to other young adults. GPs' own pvaccination was strongly predictive of their recommendation to both young adults at risk (OR = 9.6; 95%CI = 7.2-12.6 and those not at risk (OR = 8.5; 95%CI = 6.4-11.4. CONCLUSIONS/SIGNIFICANCE: These results suggest that around 60% of French private GPs followed French authorities' recommendations about vaccination of health care professionals against the A(H1N1 influenza. They pinpoint priority levers for improving preparedness for future influenza pandemics. Besides encouraging GPs

  2. Transmission dynamics of the 2009 influenza A (H1N1) pandemic in India: the impact of holiday-related school closure.

    Science.gov (United States)

    Ali, Sheikh Taslim; Kadi, A S; Ferguson, Neil M

    2013-12-01

    The role of social-distancing measures, such as school closures, is a controversial aspect of pandemic mitigation planning. However, the timing of 2009 pandemic provides a natural experiment for evaluating the impact of school closure during holidays on influenza transmission. To quantify the transmission intensity of the influenza A (H1N1) pdm'09 in India, by estimating the time varying reproduction number (Rt) and correlating the temporal changes in the estimates of Rt for different regions of India with the timing of school holidays. We used daily lab-confirmed case reports of influenza A (H1N1) pdm'09 in India (during 17 May'09 to 17 May'10), stratified by regions. We estimated the transmissibility of the pandemic for different regions from these time-series, using Bayesian methods applied to a branching process model of disease spread and correlated the resulting estimates with the timing of school holidays in each region. The North-west region experienced two notable waves, with the peak of the first wave coinciding with the start of a 4 week school holiday (September-October'09). In the southern region the two waves were less clear cut, though again the first peak of the first wave coincided with the start of school holidays--albeit of less than 2 weeks duration (August'09). Our analysis suggests that the school holidays had a significant influence on the epidemiology of the 2009 pandemic in India. We estimate that school holidays reduced the reproduction number by 14-27% in different regions of India, relative to levels seen outside holiday periods. The estimates of the reproduction number obtained (with peak R values below 1.5) are compatible with those reported from other regions of the world. This work reinforces past studies showing the significant impact of school holidays on spread of 2009 pandemic virus, and by inference the role of contact patterns in children on transmission. Copyright © 2013 Sheikh Taslim Ali Elsevier B.V. Published by Elsevier B

  3. Impact of influenza in the post-pandemic phase: Clinical features in hospitalized patients with influenza A (H1N1) pdm09 and H3N2 viruses, during 2013 in Santa Fe, Argentina.

    Science.gov (United States)

    Kusznierz, Gabriela; Carolina, Cudós; Manuel, Rudi Juan; Sergio, Lejona; Lucila, Ortellao; Julio, Befani; Mirta, Villani; Pedro, Morana; Graciana, Morera; Andrea, Uboldi; Elsa, Zerbini

    2017-07-01

    It is important to characterize the clinical and epidemiological pattern of the influenza A (H1N1) pdm09 virus and compare it with influenza A (H3N2) virus, as surveyed in just a few studies, in order to contribute to the implementation and strengthening of influenza control and prevention strategies. The aims in this study were to describe influenza clinical and epidemiological characteristics in hospitalized patients, caused by influenza A (H1N1)pdm09 and influenza A (H3N2) viruses during 2013, in Santa Fe, Argentina. A retrospective study was conducted over 2013 among hospitalized patients with laboratory-confirmed influenza diagnosis. In contrast to patients with influenza A (H3N2) (20.5%), a higher proportion of hospitalizations associated with influenza H1N1pdm were reported among adults aged 35-65 years (42.8%). Of all patients, 73.6% had an underlying medical condition. Hospitalized patients with H1N1pdm were subject to 2.6 (95%CI, 1.0-6.8) times higher risk of severity, than those hospitalized with influenza A (H3N2). This results demonstrate the impact in the post-pandemic era of H1N1pdm virus, with increased risk of severe disease, in relation to H3N2 virus, both viruses co-circulating during 2013. © 2017 Wiley Periodicals, Inc.

  4. Influenza A (H1N1) neuraminidase inhibitors from Vitis amurensis

    DEFF Research Database (Denmark)

    Nguyen, Ngoc Anh; Dao, Trong Tuan; Tung, Bui Thanh

    2011-01-01

    Recently, a novel H1N1 influenza A virus (H1N1/09 virus) was identified and considered a strong candidate for a novel influenza pandemic. As part of an ongoing anti-influenza screening programme on natural products, eight oligostilbenes were isolated as active principles from the methanol extract...... of Vitis amurensis. This manuscript reports the isolation, structural elucidation, and anti-viral activities of eight compounds on various neuraminidases from influenza A/PR/8/34 (H1N1), novel swine-origin influenza A (H1N1), and oseltamivir-resistant novel H1N1 (H274Y) expressed in 293T cells...

  5. Increase in IFNγ(-IL-2(+ cells in recent human CD4 T cell responses to 2009 pandemic H1N1 influenza.

    Directory of Open Access Journals (Sweden)

    Jason M Weaver

    Full Text Available Human CD4 T cell recall responses to influenza virus are strongly biased towards Type 1 cytokines, producing IFNγ, IL-2 and TNFα. We have now examined the effector phenotypes of CD4 T cells in more detail, particularly focusing on differences between recent versus long-term, multiply-boosted responses. Peptides spanning the proteome of temporally distinct influenza viruses were distributed into pools enriched for cross-reactivity to different influenza strains, and used to stimulate antigen-specific CD4 T cells representing recent or long-term memory. In the general population, peptides unique to the long-circulating influenza A/New Caledonia/20/99 (H1N1 induced Th1-like responses biased toward the expression of IFNγ(+TNFα(+ CD4 T cells. In contrast, peptide pools enriched for non-cross-reactive peptides of the pandemic influenza A/California/04/09 (H1N1 induced more IFNγ(-IL-2(+TNFα(+ T cells, similar to the IFNγ(-IL-2(+ non-polarized, primed precursor T cells (Thpp that are a predominant response to protein vaccination. These results were confirmed in a second study that compared samples taken before the 2009 pandemic to samples taken one month after PCR-confirmed A/California/04/09 infection. There were striking increases in influenza-specific TNFα(+, IFNγ(+, and IL-2(+ cells in the post-infection samples. Importantly, peptides enriched for non-cross-reactive A/California/04/09 specificities induced a higher proportion of Thpp-like IFNγ(-IL-2(+TNFα(+ CD4 T cells than peptide pools cross-reactive with previous influenza strains, which induced more Th1 (IFNγ(+TNFα(+ responses. These IFNγ(-IL-2(+TNFα(+ CD4 T cells may be an important target population for vaccination regimens, as these cells are induced upon infection, may have high proliferative potential, and may play a role in providing future effector cells during subsequent infections.

  6. Systems-level comparison of host responses induced by pandemic and seasonal influenza A H1N1 viruses in primary human type I-like alveolar epithelial cells in vitro

    Directory of Open Access Journals (Sweden)

    Guan Yi

    2010-10-01

    Full Text Available Abstract Background Pandemic influenza H1N1 (pdmH1N1 virus causes mild disease in humans but occasionally leads to severe complications and even death, especially in those who are pregnant or have underlying disease. Cytokine responses induced by pdmH1N1 viruses in vitro are comparable to other seasonal influenza viruses suggesting the cytokine dysregulation as seen in H5N1 infection is not a feature of the pdmH1N1 virus. However a comprehensive gene expression profile of pdmH1N1 in relevant primary human cells in vitro has not been reported. Type I alveolar epithelial cells are a key target cell in pdmH1N1 pneumonia. Methods We carried out a comprehensive gene expression profiling using the Affymetrix microarray platform to compare the transcriptomes of primary human alveolar type I-like alveolar epithelial cells infected with pdmH1N1 or seasonal H1N1 virus. Results Overall, we found that most of the genes that induced by the pdmH1N1 were similarly regulated in response to seasonal H1N1 infection with respect to both trend and extent of gene expression. These commonly responsive genes were largely related to the interferon (IFN response. Expression of the type III IFN IL29 was more prominent than the type I IFN IFNβ and a similar pattern of expression of both IFN genes was seen in pdmH1N1 and seasonal H1N1 infection. Genes that were significantly down-regulated in response to seasonal H1N1 but not in response to pdmH1N1 included the zinc finger proteins and small nucleolar RNAs. Gene Ontology (GO and pathway over-representation analysis suggested that these genes were associated with DNA binding and transcription/translation related functions. Conclusions Both seasonal H1N1 and pdmH1N1 trigger similar host responses including IFN-based antiviral responses and cytokine responses. Unlike the avian H5N1 virus, pdmH1N1 virus does not have an intrinsic capacity for cytokine dysregulation. The differences between pdmH1N1 and seasonal H1N1 viruses

  7. A Tale of Many Cities: A Contemporary Historical Study of the Implementation of School Closures during the 2009 pA(H1N1) Influenza Pandemic.

    Science.gov (United States)

    Navarro, J Alexander; Kohl, Katrin S; Cetron, Martin S; Markel, Howard

    2016-06-01

    Applying qualitative historical methods, we examined the consideration and implementation of school closures as a nonpharmaceutical intervention (NPI) in thirty US cities during the spring 2009 wave of the pA(H1N1) influenza pandemic. We gathered and performed close textual readings of official federal, state, and municipal government documents; media coverage; and academic publications. Lastly, we conducted oral history interviews with public health and education officials in our selected cities. We found that several local health departments pursued school closure plans independent of CDC guidance, that uncertainty of action and the rapidly evolving understanding of pA(H1N1) contributed to tension and pushback from the public, that the media and public perception played a significant role in the response to school closure decisions, and that there were some notable instances of interdepartmental communication breakdown. We conclude that health departments should continue to develop and fine-tune their action plans while also working to develop better communication methods with the public, and work more closely with education officials to better understand the complexities involved in closing schools. Lastly, state and local governments should work to resolve lingering issues of legal authority for school closures in times of public health crises. Copyright © 2016 by Duke University Press.

  8. Underreporting of 2009 H1N1 Influenza Cases

    Centers for Disease Control (CDC) Podcasts

    2009-12-08

    Influenza cases are difficult to track because many people don't go to the doctor or get tested for flu when they're sick. The first months of the 2009 H1N1 influenza pandemic were no different. In this podcast, CDC's Dr. Carrie Reed discusses a study in the December issue of Emerging Infectious Diseases that looked at the actual number of cases reported and estimated the true number of cases when correcting for underreporting.  Created: 12/8/2009 by Emerging Infectious Diseases.   Date Released: 12/8/2009.

  9. Using high-throughput sequencing to leverage surveillance of genetic diversity and oseltamivir resistance: a pilot study during the 2009 influenza A(H1N1 pandemic.

    Directory of Open Access Journals (Sweden)

    Juan Téllez-Sosa

    Full Text Available BACKGROUND: Influenza viruses display a high mutation rate and complex evolutionary patterns. Next-generation sequencing (NGS has been widely used for qualitative and semi-quantitative assessment of genetic diversity in complex biological samples. The "deep sequencing" approach, enabled by the enormous throughput of current NGS platforms, allows the identification of rare genetic viral variants in targeted genetic regions, but is usually limited to a small number of samples. METHODOLOGY AND PRINCIPAL FINDINGS: We designed a proof-of-principle study to test whether redistributing sequencing throughput from a high depth-small sample number towards a low depth-large sample number approach is feasible and contributes to influenza epidemiological surveillance. Using 454-Roche sequencing, we sequenced at a rather low depth, a 307 bp amplicon of the neuraminidase gene of the Influenza A(H1N1 pandemic (A(H1N1pdm virus from cDNA amplicons pooled in 48 barcoded libraries obtained from nasal swab samples of infected patients (n  =  299 taken from May to November, 2009 pandemic period in Mexico. This approach revealed that during the transition from the first (May-July to second wave (September-November of the pandemic, the initial genetic variants were replaced by the N248D mutation in the NA gene, and enabled the establishment of temporal and geographic associations with genetic diversity and the identification of mutations associated with oseltamivir resistance. CONCLUSIONS: NGS sequencing of a short amplicon from the NA gene at low sequencing depth allowed genetic screening of a large number of samples, providing insights to viral genetic diversity dynamics and the identification of genetic variants associated with oseltamivir resistance. Further research is needed to explain the observed replacement of the genetic variants seen during the second wave. As sequencing throughput rises and library multiplexing and automation improves, we foresee that

  10. Pre-admission statin use and in-hospital severity of 2009 pandemic influenza A(H1N1 disease.

    Directory of Open Access Journals (Sweden)

    Stephen J Brett

    2011-04-01

    Full Text Available Statins are drugs that are used to lower plasma cholesterol levels. Recently, contradictory claims have been made about possible additional effects of statins on progression of a variety of inflammatory disorders, including infections. We therefore examined the clinical course of patients admitted to hospital with 2009 pandemic influenza A(H1N1, who were or weren't taking statins at time of admission.A retrospective case-control study was performed using the United Kingdom Influenza Clinical Information Network (FLU-CIN database, containing detailed information on 1,520 patients admitted to participating hospitals with confirmed 2009 pandemic influenza A(H1N1 infection between April 2009 and January 2010. We confined our analysis to those aged over 34 years. Univariate analysis was used to calculate unadjusted odds ratios (OR and 95 percent confidence intervals (95%CI for factors affecting progression to severe outcome (high dependency or intensive care unit level support or death (cases; two multivariable logistic regression models were then established for age and sex, and for age, sex, obesity and "indication for statin" (e.g., heart disease or hypercholesterolaemia.We found no statistically significant association between pre-admission statin use and severity of outcome after adjustment for age and sex [adjusted OR: 0.81 (95% CI: 0.46-1.38; n = 571]. After adjustment for age, sex, obesity and indication for statin, the association between pre-admission statin use and severe outcome was not statistically significant; point estimates are compatible with a small but clinically significant protective effect of statin use [adjusted OR: 0.72 (95% CI: 0.38-1.33].In this group of patients hospitalized with pandemic influenza, a significant beneficial effect of pre-admission statin use on the in-hospital course of illness was not identified. Although the database from which these observations are derived represents the largest available suitable

  11. Effectiveness of the AS03-adjuvanted vaccine against pandemic influenza virus A/(H1N1 2009--a comparison of two methods; Germany, 2009/10.

    Directory of Open Access Journals (Sweden)

    Helmut Uphoff

    Full Text Available During the autumn wave of the pandemic influenza virus A/(H1N1 2009 (pIV the German population was offered an AS03-adjuvanted vaccine. The authors compared results of two methods calculating the effectiveness of the vaccine (VE. The test-negative case-control method used data from virologic surveillance including influenza-positive and negative patients. An innovative case-series methodology explored data from all nationally reported laboratory-confirmed influenza cases. The proportion of reported cases occurring in vaccinees during an assumed unprotected phase after vaccination was compared with that occurring in vaccinees during their assumed protected phase. The test-negative case-control method included 1,749 pIV cases and 2,087 influenza test-negative individuals of whom 6 (0.3% and 36 (1.7%, respectively, were vaccinated. The case series method included data from 73,280 cases. VE in the two methods was 79% (95% confidence interval (CI = 35-93%; P = 0.007 and 87% (95% CI = 78-92%; P<0.001 for individuals less than 14 years of age and 70% (95% CI = -45%-94%, P = 0.13 and 74% (95% CI = 64-82%; P<0.001 for individuals above the age of 14. Both methods yielded similar VE in both age groups; and VE for the younger age group seemed to be higher.

  12. Duration of 18F-FDG avidity in lymph nodes after pandemic H1N1v and seasonal influenza vaccination

    International Nuclear Information System (INIS)

    Thomassen, Anders; Lerberg Nielsen, Anne; Gerke, Oke; Johansen, Allan; Petersen, Henrik

    2011-01-01

    The aim of our study was to investigate the occurrence of fluorodeoxyglucose (FDG) avidity in draining axillary lymph nodes after vaccination against influenza (H1N1v pandemic and seasonal) and to determine the period of increased FDG uptake. During December 2009, patients referred for 18 F-FDG positron emission tomography (PET)/CT scans (n = 293) filled in a questionnaire concerning vaccination type (seasonal and/or H1N1v), time and anatomical localization of vaccination. Only injections in deltoid regions were evaluated, thus ensuring that draining lymph nodes were axillary. If more vaccinations had been given, only the latest vaccination was evaluated in each deltoid region. Of all patients who underwent PET/CT scans during December 2009, 26% had been vaccinated with at least one influenza vaccination in the deltoid region. A total of 92 'draining' and 60 'reference' (i.e. contralateral, non-vaccinated) axillary lymph nodes were evaluated in 61 patients (19 of 61 patients were scanned twice). The maximal intensity in FDG uptake (SUV max ) in draining lymph nodes was 5 g/ml body weight (BW), whereas the maximal intensity in reference lymph nodes was 1.9 g/ml BW. The SUV max was normalized approximately 40 days after vaccination. No significant enlargement of metabolically active draining lymph nodes could be demonstrated on CT scan. Chemotherapy or immunosuppressive drugs given within 2 weeks from vaccination did not affect SUV max in the axillary lymph nodes. Influenza vaccination may lead to FDG-avid draining lymph nodes beyond 1 month. (orig.)

  13. Duration of {sup 18}F-FDG avidity in lymph nodes after pandemic H1N1v and seasonal influenza vaccination

    Energy Technology Data Exchange (ETDEWEB)

    Thomassen, Anders; Lerberg Nielsen, Anne; Gerke, Oke; Johansen, Allan; Petersen, Henrik [OUH, Odense University Hospital, Department of Nuclear Medicine, Odense C (Denmark)

    2011-05-15

    The aim of our study was to investigate the occurrence of fluorodeoxyglucose (FDG) avidity in draining axillary lymph nodes after vaccination against influenza (H1N1v pandemic and seasonal) and to determine the period of increased FDG uptake. During December 2009, patients referred for {sup 18}F-FDG positron emission tomography (PET)/CT scans (n = 293) filled in a questionnaire concerning vaccination type (seasonal and/or H1N1v), time and anatomical localization of vaccination. Only injections in deltoid regions were evaluated, thus ensuring that draining lymph nodes were axillary. If more vaccinations had been given, only the latest vaccination was evaluated in each deltoid region. Of all patients who underwent PET/CT scans during December 2009, 26% had been vaccinated with at least one influenza vaccination in the deltoid region. A total of 92 'draining' and 60 'reference' (i.e. contralateral, non-vaccinated) axillary lymph nodes were evaluated in 61 patients (19 of 61 patients were scanned twice). The maximal intensity in FDG uptake (SUV{sub max}) in draining lymph nodes was 5 g/ml body weight (BW), whereas the maximal intensity in reference lymph nodes was 1.9 g/ml BW. The SUV{sub max} was normalized approximately 40 days after vaccination. No significant enlargement of metabolically active draining lymph nodes could be demonstrated on CT scan. Chemotherapy or immunosuppressive drugs given within 2 weeks from vaccination did not affect SUV{sub max} in the axillary lymph nodes. Influenza vaccination may lead to FDG-avid draining lymph nodes beyond 1 month. (orig.)

  14. Health services utilization, work absenteeism and costs of pandemic influenza A (H1N1) 2009 in Spain: a multicenter-longitudinal study.

    Science.gov (United States)

    Galante, Mariana; Garin, Olatz; Sicuri, Elisa; Cots, Francesc; García-Altés, Anna; Ferrer, Montserrat; Dominguez, Àngela; Alonso, Jordi

    2012-01-01

    The aim of this study was to estimate healthcare resource utilization, work absenteeism and cost per patient with pandemic influenza (H1N1)2009, from its beginning to March 2010, in Spain. We also estimated the economic impact on healthcare services. Longitudinal, descriptive, multicenter study of in- and outpatients with confirmed diagnosis of influenza A (H1N1) in Spain. Temporal distribution of cases was comparable to that in Spain. Information of healthcare and social resources used from one week before admission (inpatient) or index-medical visit (outpatient) until recovery was gathered. Unit cost was imputed to utilization frequency for the monetary valuation of use. Mean cost per patient was calculated. A sensitivity analysis was conducted, and variables correlated with cost per patient were identified. Economic impact on the healthcare system was estimated using healthcare costs per patient and both, the reported number of confirmed and clinical cases in Spain. 172 inpatients and 224 outpatients were included. Less than 10% were over 65 years old and more than 50% had previous comorbidities. 12.8% of inpatients were admitted to the Intensive Care Unit. Mean length of hospital stay of patients not requiring critical care was 5 days (SD = 4.4). All working-inpatients and 91.7% working-outpatients went on sick leave. On average, work absenteeism was 30.5 days (SD = 20.7) for the first ones and 9 days (SD = 6.3) for the latest. Caregivers of 21.7% of inpatients and 8.5% of outpatients also had work absenteeism during 10.7 and 4.1 days on average respectively. Mean cost was €6,236/inpatient (CI95% = 1,384-14,623) and €940/outpatient (CI95% = 66-3,064). The healthcare economic burden of patients with confirmed influenza was €144,773,577 (IC95% 13,753,043-383,467,535). More than 86% of expenditures were a result of outpatients' utilization. Cost per H1N1-patient did not defer much from seasonal influenza estimates. Hospitalizations and work absenteeism

  15. Kinetic, thermodynamic and structural analysis of tamiphosphor binding to neuraminidase of H1N1 (2009) pandemic influenza

    Czech Academy of Sciences Publication Activity Database

    Albinana, C. B.; Machara, A.; Řezáčová, Pavlína; Pachl, P.; Konvalinka, J.; Kožíšek, M.

    2016-01-01

    Roč. 121, OCT 4 (2016), s. 100-109 ISSN 0223-5234 R&D Projects: GA ČR GA13-19561S; GA MŠk LO1302; GA MŠk(CZ) LO1304 Institutional support: RVO:68378050 Keywords : Influenza neuraminidase * Oseltamivir * Tamiphosphor * Isothermal titration calorimetry * Crystal structure * Lattice-translocation defect Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.519, year: 2016

  16. Kinetic, thermodynamic and structural analysis of tamiphosphor binding to neuraminidase of H1N1 (2009) pandemic influenza

    Czech Academy of Sciences Publication Activity Database

    Albinana, C. B.; Machara, A.; Řezáčová, Pavlína; Pachl, Petr; Konvalinka, Jan; Kožíšek, Milan

    2016-01-01

    Roč. 121, Oct 4 (2016), s. 100-109 ISSN 0223-5234 R&D Projects: GA ČR GA13-19561S; GA MŠk LO1302; GA MŠk(CZ) LO1304 Institutional support: RVO:61388963 Keywords : influenza neuraminidase * oseltamivir * tamiphosphor * isothermal titration calorimetry * crystal structure * lattice-translocation defect Subject RIV: CE - Biochemistry Impact factor: 4.519, year: 2016

  17. Internet-based surveillance of Influenza-like-illness in the UK during the 2009 H1N1 influenza pandemic

    Directory of Open Access Journals (Sweden)

    Ealden Toby

    2010-10-01

    Full Text Available Abstract Background Internet-based surveillance systems to monitor influenza-like illness (ILI have advantages over traditional (physician-based reporting systems, as they can potentially monitor a wider range of cases (i.e. including those that do not seek care. However, the requirement for participants to have internet access and to actively participate calls into question the representativeness of the data. Such systems have been in place in a number of European countries over the last few years, and in July 2009 this was extended to the UK. Here we present results of this survey with the aim of assessing the reliability of the data, and to evaluate methods to correct for possible biases. Methods Internet-based monitoring of ILI was launched near the peak of the first wave of the UK H1N1v influenza pandemic. We compared the recorded ILI incidence with physician-recorded incidence and an estimate of the true number of cases over the course of the epidemic. We also compared overall attack rates. The effect of using different ILI definitions and alternative denominator assumptions on incidence estimates was explored. Results The crude incidence measured by the internet-based system appears to be influenced by individuals who participated only once in the survey and who appeared more likely to be ill. This distorted the overall incidence trend. Concentrating on individuals who reported more than once results in a time series of ILI incidence that matches the trend of case estimates reasonably closely, with a correlation of 0.713 (P-value: 0.0001, 95% CI: 0.435, 0.867. Indeed, the internet-based system appears to give a better estimate of the relative height of the two waves of the UK pandemic than the physician-recorded incidence. The overall attack rate is, however, higher than other estimates, at about 16% when compared with a model-based estimate of 6%. Conclusion Internet-based monitoring of ILI can capture the trends in case numbers if

  18. Factors Influencing School Closure and Dismissal Decisions: Influenza A (H1N1), Michigan 2009

    Science.gov (United States)

    Dooyema, Carrie A.; Copeland, Daphne; Sinclair, Julie R.; Shi, Jianrong; Wilkins, Melinda; Wells, Eden; Collins, Jim

    2014-01-01

    Background: In fall 2009, many US communities experienced school closures during the influenza A H1N1 pandemic (pH1N1) and the state of Michigan reported 567 closures. We conducted an investigation in Michigan to describe pH1N1-related school policies, practices, and identify factors related to school closures. Methods: We distributed an online…

  19. 'Out of two bad choices, I took the slightly better one': vaccination dilemmas for Scottish and Polish migrant women during the H1N1 influenza pandemic.

    Science.gov (United States)

    Sim, J A; Ulanika, A A; Katikireddi, S V; Gorman, D

    2011-08-01

    Pregnancy has been identified as a risk factor for complications from pandemic H1N1 influenza, and pregnant women were identified as a target group for vaccination in the UK in the 2009 pandemic. Poland took a more conservative approach, and did not offer vaccination to pregnant women. Poland accounts for the largest wave of recent migrants to the UK, many of whom are in their reproductive years and continue to participate actively in Polish healthcare systems after migration. The authors speculated that different national responses may shape differences in approaches to the vaccine between Scottish and Polish women. This study therefore aimed to assess how pregnant Polish migrants to Scotland weighed up the risks and benefits of the vaccine for pandemic H1N1 influenza in comparison with their Scottish counterparts. A qualitative interview-based study comparing the views of Scottish and Polish pregnant women on H1N1 vaccination was carried out in 'real time' during the first 2 weeks of the vaccination programme in November 2009. One-to-one interviews were conducted with 10 women (five Polish and five Scottish) in their native language. Interviews were transcribed, translated, coded and analysed for differences and similarities in decision-making processes between the two groups. Contrary to expectations, Scottish and Polish women drew on a strikingly similar set of considerations in deciding whether or not to accept the vaccine, with individual women reaching different conclusions. Almost all of the women adopted a critical stance towards the vaccine. While most women understood that pregnancy was a risk factor for complications from influenza, their primary concern was protecting family health overall and their fetus in particular. Deciding whether or not to accept the vaccine was difficult for women. Some identified a contradiction between the culture of caution which characterizes pregnancy-related advice, and the fact that they were being urged to accept what

  20. EFSA Panel Animal Health and Welfare (AHAW); Scientific Opinion on the pandemic (H1N1) 2009 influenza and its potential implications for animal health

    DEFF Research Database (Denmark)

    Bøtner, Anette; Brown, Ian; Capua, Ilaria

    . Occasionally, pigs have been infected following exposure to pH1N1 infected humans. In pigs, a subclinical course was common and when clinical signs were seen (coughing, fever) they were generally mild. Presently, the clinical impact of pH1N1virus on the EU pig population is considered minimal. In poultry....... Such vaccines efficiently prevent disease by reducing virus replication in the lungs. However, voluntary vaccination of swine with these vaccines has not halted the circulation of SIV in swine. There is no urgency for vaccination of pigs against pH1N1 virus. Currently, no vaccines against H1 viruses for poultry...... are available but at present, there is no need to vaccinate poultry against pH1N1 virus. Monitoring of circulating influenza viruses in swine and poultry populations should be instigated to monitor the evolution of the pH1N1 virus including changes in virulence....

  1. Personal decision-making criteria related to seasonal and pandemic A(H1N1 influenza-vaccination acceptance among French healthcare workers.

    Directory of Open Access Journals (Sweden)

    Lila Bouadma

    Full Text Available BACKGROUND: Influenza-vaccination rates among healthcare workers (HCW remain low worldwide, even during the 2009 A(H1N1 pandemic. In France, this vaccination is free but administered on a voluntary basis. We investigated the factors influencing HCW influenza vaccination. METHODS: In June-July 2010, HCW from wards of five French hospitals completed a cross-sectional survey. A multifaceted campaign aimed at improving vaccination coverage in this hospital group was conducted before and during the 2009 pandemic. Using an anonymous self-administered questionnaire, we assessed the relationships between seasonal (SIV and pandemic (PIV influenza vaccinations, and sociodemographic and professional characteristics, previous and current vaccination statuses, and 33 statements investigating 10 sociocognitive domains. The sociocognitive domains describing HCWs' SIV and PIV profiles were analyzed using the classification-and-regression-tree method. RESULTS: Of the HCWs responding to our survey, 1480 were paramedical and 401 were medical with 2009 vaccination rates of 30% and 58% for SIV and 21% and 71% for PIV, respectively (p<0.0001 for both SIV and PIV vaccinations. Older age, prior SIV, working in emergency departments or intensive care units, being a medical HCW and the hospital they worked in were associated with both vaccinations; while work shift was associated only with PIV. Sociocognitive domains associated with both vaccinations were self-perception of benefits and health motivation for all HCW. For medical HCW, being a role model was an additional domain associated with SIV and PIV. CONCLUSIONS: Both vaccination rates remained low. Vaccination mainly depended on self-determined factors and for medical HCW, being a role model.

  2. Risk of narcolepsy associated with inactivated adjuvanted (AS03 A/H1N1 (2009 pandemic influenza vaccine in Quebec.

    Directory of Open Access Journals (Sweden)

    Jacques Montplaisir

    Full Text Available An association between an adjuvanted (AS03 A/H1N1 pandemic vaccine and narcolepsy has been reported in Europe.To assess narcolepsy risk following administration of a similar vaccine in Quebec.Retrospective population-based study.Neurologists and lung specialists in the province were invited to report narcolepsy cases to a single reference centre.Patients were interviewed by two sleep experts and standard diagnostic tests were performed. Immunization status was verified in the provincial pandemic influenza vaccination registry.Confirmed narcolepsy with or without cataplexy with onset of excessive daytime sleepiness between January 1st, 2009, and December 31st, 2010. Relative risks (RRs were calculated using a Poisson model in a cohort analysis, by a self-controlled case series (SCCS and a case-control method.A total of 24 cases were included and overall incidence rate was 1.5 per million person-years. A cluster of 7 cases was observed among vaccinated persons in the winter 2009-2010. In the primary cohort analysis, 16-week post-vaccination RR was 4.32 (95% CI: 1.50-11.12. RR was 2.07 (0.70-6.17 in the SCCS, and 1.48 (0.37-7.03 using the case-control method. Estimates were lower when observation was restricted to the period of pandemic influenza circulation, and tended to be higher in persons <20 years old and for cataplexy cases.Results are compatible with an excess risk of approximately one case per million vaccine doses, mainly in persons less than 20 years of age. However, a confounding effect of the influenza infection cannot be ruled out.

  3. The epidemiology and surveillance response to pandemic influenza A (H1N1) among local health departments in the San Francisco Bay Area.

    Science.gov (United States)

    Enanoria, Wayne T A; Crawley, Adam W; Tseng, Winston; Furnish, Jasmine; Balido, Jeannie; Aragón, Tomás J

    2013-03-27

    Public health surveillance and epidemiologic investigations are critical public health functions for identifying threats to the health of a community. Very little is known about how these functions are conducted at the local level. The purpose of the Epidemiology Networks in Action (EpiNet) Study was to describe the epidemiology and surveillance response to the 2009 pandemic influenza A (H1N1) by city and county health departments in the San Francisco Bay Area in California. The study also documented lessons learned from the response in order to strengthen future public health preparedness and response planning efforts in the region. In order to characterize the epidemiology and surveillance response, we conducted key informant interviews with public health professionals from twelve local health departments in the San Francisco Bay Area. In order to contextualize aspects of organizational response and performance, we recruited two types of key informants: public health professionals who were involved with the epidemiology and surveillance response for each jurisdiction, as well as the health officer or his/her designee responsible for H1N1 response activities. Information about the organization, data sources for situation awareness, decision-making, and issues related to surge capacity, continuity of operations, and sustainability were collected during the key informant interviews. Content and interpretive analyses were conducted using ATLAS.ti software. The study found that disease investigations were important in the first months of the pandemic, often requiring additional staff support and sometimes forcing other public health activities to be put on hold. We also found that while the Incident Command System (ICS) was used by all participating agencies to manage the response, the manner in which it was implemented and utilized varied. Each local health department (LHD) in the study collected epidemiologic data from a variety of sources, but only case reports

  4. Mature Turkey Breeder Hens Exposed to Pandemic Influenza H1N1: Resultant Effects on Morbidity, Mortality, and Fecundity.

    Science.gov (United States)

    Evans, Robert; Bommineni, Yugendar; Falk, Jonathan; Blackway, Adam; Young, Brent; Isenhart, Connie

    2015-03-01

    During the artificial insemination process, turkey breeder hens may become infected with influenza virus acquired from humans. The virus has been shown, through experimental infection, to localize in the reproductive tract, with limited dissemination in other tissues. A limited number of hens were used during these studies, and the overall flock morbidity, mortality, and fecundity were not able to be determined. The current case follows the progression of clinical signs in a flock of commercial breeder hens from onset of egg production losses in one house through the subsequent drops in four remaining houses. Each house contained approximately 3000 hens and followed a sequential loss of shell quality, reduced numbers of eggs, and fertility, while mild clinical signs were observed and mortality was slightly increased in a house with concurrent fowl cholera (Pasturella multocida) infection.

  5. Events supposedly attributable to vaccination or immunization during pandemic influenza A (H1N1) vaccination campaigns in Latin America and the Caribbean.

    Science.gov (United States)

    Ropero-Álvarez, A M; Whittembury, A; Bravo-Alcántara, P; Kurtis, H J; Danovaro-Holliday, M C; Velandia-González, M

    2015-01-01

    As part of the vaccination activities against influenza A[H1N1]pdm vaccine in 2009-2010, countries in Latin American and the Caribbean (LAC) implemented surveillance of events supposedly attributable to vaccines and immunization (ESAVI). We describe the serious ESAVI reported in LAC in order to further document the safety profile of this vaccine and highlight lessons learned. We reviewed data from serious H1N1 ESAVI cases from LAC countries reported to the Pan American Health Organization/World Health Organization. We estimated serious ESAVI rates by age and target group, as well as by clinical diagnosis, and completed descriptive analyses of final outcomes and classifications given in country. A total of 1000 serious ESAVI were reported by 18 of the 29 LAC countries that vaccinated against A[H1N1]pdm. The overall reporting rate in LAC was 6.91 serious ESAVI per million doses, with country reporting rates ranging from 0.77 to 64.68 per million doses. Rates were higher among pregnant women (16.25 per million doses) when compared to health care workers (13.54 per million doses) and individuals with chronic disease (4.03 per million doses). The top three most frequent diagnoses were febrile seizures (12.0%), Guillain-Barré Syndrome (10.5%) and acute pneumonia (8.0%). Almost half (49.1%) of the serious ESAVI were reported among children aged ESAVI reported, 37.8% were classified as coincidental, 35.3% as related to vaccine components, 26.4% as non-conclusive and 0.5% as a programmatic error. This regional overview of A[H1N1]pdm vaccine safety data in LAC estimated the rate of serious ESAVI at lower levels than other studies. However, the ESAVI diagnosis distribution is comparable to the published literature. Lessons learned can be applied in the response to future pandemics. Copyright © 2014. Published by Elsevier Ltd.

  6. What happened after the initial global spread of pandemic human influenza virus A (H1N1? A population genetics approach

    Directory of Open Access Journals (Sweden)

    Martinez-Hernandez Fernando

    2010-08-01

    Full Text Available Abstract Viral population evolution dynamics of influenza A is crucial for surveillance and control. In this paper we analyzed viral genetic features during the recent pandemic caused by the new influenza human virus A H1N1, using a conventional population genetics approach based on 4689 hemagglutinin (HA and neuraminidase (NA sequences available in GenBank submitted between March and December of 2009. This analysis showed several relevant aspects: a a scarce initial genetic variability within the viral isolates from some countries that increased along 2009 when influenza was dispersed around the world; b a worldwide virus polarized behavior identified when comparing paired countries, low differentiation and high gene flow were found in some pairs and high differentiation and moderate or scarce gene flow in others, independently of their geographical closeness, c lack of positive selection in HA and NA due to increase of the population size of virus variants, d HA and NA variants spread in a few months all over the world being identified in the same countries in different months along 2009, and e containment of viral variants in Mexico at the beginning of the outbreak, probably due to the control measures applied by the government.

  7. Pandemic H1N1 2009 virus in Danish pigs: Diagnosis and lack of surveillance

    DEFF Research Database (Denmark)

    Larsen, Lars Erik; Nielsen, L. P.; Breum, Solvej Østergaard

    In March-April 2009, a novel pandemic H1N1 virus (H1N1v) of likely swine origin emerged in the human population globally. The first case in pigs was reported from Canada in May 2009 and presently almost all countries with pig production have reported cases. The emergence of a new influenza subtype...

  8. Broadly-reactive human monoclonal antibodies elicited following pandemic H1N1 influenza virus exposure protect mice from highly pathogenic H5N1 challenge.

    Science.gov (United States)

    Nachbagauer, Raffael; Shore, David; Yang, Hua; Johnson, Scott K; Gabbard, Jon D; Tompkins, S Mark; Wrammert, Jens; Wilson, Patrick C; Stevens, James; Ahmed, Rafi; Krammer, Florian; Ellebedy, Ali H

    2018-06-13

    Broadly cross-reactive antibodies that recognize conserved epitopes within the influenza virus hemagglutinin (HA) stalk domain are of particular interest for their potential use as therapeutic and prophylactic agents against multiple influenza virus subtypes including zoonotic virus strains. Here, we characterized four human HA stalk-reactive monoclonal antibodies (mAbs) for their binding breadth and affinity, in vitro neutralization capacity, and in vivo protective potential against an highly pathogenic avian influenza virus. The monoclonal antibodies were isolated from individuals shortly following infection with (70-1F02 and 1009-3B05) or vaccination against (05-2G02 and 09-3A01) A(H1N1)pdm09. Three of the mAbs bound HAs from multiple strains of group 1 viruses, and one mAb, 05-2G02, bound to both group 1 and group 2 influenza A HAs. All four antibodies prophylactically protected mice against a lethal challenge with the highly pathogenic A/Vietnam/1203/04 (H5N1) strain. Two mAbs, 70-1F02 and 09-3A01, were further tested for their therapeutic efficacy against the same strain and showed good efficacy in this setting as well. One mAb, 70-1F02, was co-crystallized with H5 HA and showed similar heavy chain only interactions as a the previously described anti-stalk antibody CR6261. Finally, we showed that antibodies that compete with these mAbs are prevalent in serum from an individual recently infected with A(H1N1)pdm09 virus. The antibodies described here can be developed into broad-spectrum antiviral therapeutics that could be used to combat infections with zoonotic or emerging pandemic influenza viruses. IMPORTANCE The rise in zoonotic infections of humans with emerging influenza viruses is a worldwide public health concern. The majority of recent zoonotic human influenza cases were caused by H7N9 and H5Nx viruses and were associated with high morbidity and mortality. In addition, seasonal influenza viruses are estimated to cause up to 650,000 deaths annually

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

    Science.gov (United States)

    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...

  10. Contact behaviour of children and parental employment behaviour during school closures against the pandemic influenza A (H1N1-2009) in Japan.

    Science.gov (United States)

    Mizumoto, Kenji; Yamamoto, Taro; Nishiura, Hiroshi

    2013-06-01

    To identify epidemiological determinants of the contact behaviour of children and their impact on parental employment, during school closures that took place over the course of the 2009 pandemic influenza (H1N1-2009) in Japan. A retrospective survey was conducted in Japanese households between October 2009 and May 2010 by administration of a standardized questionnaire. Demographic and behavioural variables were explored, in association with the frequency with which children left the home and the risk of parents being absent from work during school closures. Data from 882 eligible households were analysed. A total of 181/882 (20.5%) of households reported that children left the home for nonessential reasons during school closures. No impact on parental working hours was reported by 742/882 (84.1%) of households. Univariate analyses showed that the frequency with which children left the home was dependent on age, extent of school closure and requirement for special childcare arrangements. A greater understanding of age-dependent behaviours, during school closures as a consequence of a pandemic, is required. Consideration of a public policy to permit a paid leave of absence from work for parents during school closures may be beneficial; the cost-effectiveness of such a measure should be assessed in future.

  11. "Pandemic public health paradox": Time series analysis of the 2009/10 influenza A/H1N1 epidemiology, media attention, risk perception and public reactions in 5 European countries

    NARCIS (Netherlands)

    R. Reintjes (R.); E. Das (Enny); Klemm, C. (Celine); J.H. Richardus (Jan Hendrik); Keßler, V. (Verena); R.A. Ahmad (Riris)

    2016-01-01

    textabstractIn 2009, influenza A H1N1 caused the first pandemic of the 21st century. Although a vaccine against this influenza subtype was offered before or at the onset of the second epidemic wave that caused most of the fatal cases in Europe, vaccination rates for that season were lower than

  12. Comparative study of lymphocytes from individuals that were vaccinated and unvaccinated against the pandemic 2009-2011 H1N1 influenza virus in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Deise Nascimento de Freitas

    2015-10-01

    Full Text Available ABSTRACTINTRODUCTION:While no single factor is sufficient to guarantee the success of influenza vaccine programs, knowledge of the levels of immunity in local populations is critical. Here, we analyzed influenza immunity in a population from Southern Brazil, a region with weather conditions that are distinct from those in the rest of country, where influenza infections are endemic, and where greater than 50% of the population is vaccinated annually.METHODS:Peripheral blood mononuclear cells were isolated from 40 individuals. Of these, 20 had received the H1N1 vaccine, while the remaining 20 were unvaccinated against the disease. Cells were stimulated in vitro with the trivalent post-pandemic influenza vaccine or with conserved major histocompatibility complex I (MHC I peptides derived from hemagglutinin and neuraminidase. Cell viability was then analyzed by [3-(4,5-dimethylthiazol-2-yl-2,5- diphenyltetrazolium bromide]-based colorimetric assay (MTT, and culture supernatants were assayed for helper T type 1 (Th1 and Th2-specific cytokine levels.RESULTS:Peripheral blood lymphocytes from vaccinated, but not unvaccinated, individuals exhibited significant proliferation in vitro in the presence of a cognate influenza antigen. After culturing with vaccine antigens, cells from vaccinated individuals produced similar levels of interleukin (IL-10 and interferon (IFN-γ, while those from unvaccinated individuals produced higher levels of IFN-γ than of IL-10.CONCLUSIONS:Our data indicate that peripheral blood lymphocytes from vaccinated individuals are stimulated upon encountering a cognate antigen, but did not support the hypothesis that cross-reactive responses related to previous infections can ameliorate the immune response. Moreover, monitoring IL-10 production in vaccinated individuals could comprise a valuable tool for predicting disease evolution.

  13. Pandemic influenza A/H1N1 vaccination coverage, adverse reactions, and reasons for vaccine refusal among medical students in Brazil

    Directory of Open Access Journals (Sweden)

    Eduardo Pernambuco de Souza

    2012-04-01

    Full Text Available The aim of this cross-sectional study was to determine, among medical students at a public university in Rio de Janeiro, Brazil, the acceptance of the pandemic influenza A/H1N1 vaccine during the 2010 mass immunization campaign and the vaccine safety in this group and, among unvaccinated students, the reasons for refusing vaccination. Of a total of 858 students, 678 (79% participated in the study. Vaccination coverage was 60.4% among students aged 20 to 39 years (an age group targeted for vaccination and 43.8% among those who did not belong to this age group. The most frequent adverse reactions to the vaccine were pain at the injection site (8.7% and fever (7.9%. There were no serious adverse reactions. Among students aged 20 to 39 years, the most common reasons for refusing the vaccine were "lack of time" (42.4%, "fear of adverse reactions" (41.9%, and "difficult access to the vaccine" (11.5%. Other reasons for vaccine refusal were "uncertainties about vaccine safety and efficacy" and "vaccination was not needed". To increase the acceptance of the influenza vaccine, a comprehensive immunization program should be offered to these students.

  14. Seroprevalence of Antibodies to Pandemic (H1N1 2009 Influenza Virus Among Hospital Staff in a Medical Center in Taiwan

    Directory of Open Access Journals (Sweden)

    Yu-Jiun Chan

    2010-02-01

    Conclusion: The SPR of antibodies against the pandemic (H1N1 2009 virus in the hospital staff was higher than that in the general population, reflecting a higher contact risk. Prevaccination surveillance of the immune status of different risk groups may help to prioritize which groups should be vaccinated first.

  15. Evaluating the most effective distribution strategies to assure administration of pandemic H1N1 influenza vaccine to New York State children and adolescents: evaluation using the New York State Immunization Information System.

    Science.gov (United States)

    Bednarczyk, Robert A; DuVall, Sarah; Meldrum, Megan D; Flynn, Michael K; Santilli, Loretta A; Easton, Delia E; Sharma, Priya; Blog, Debra S; Zansky, Shelley M; McNutt, Louise-Anne; Birkhead, Guthrie S

    2013-01-01

    To examine differences in H1N1 influenza vaccine distribution strategies that may impact the ability to rapidly administer vaccine during a pandemic or public health emergency. Retrospective evaluation of immunization data in the New York State Immunization Information System (NYSIIS). Analysis of existing NYSIIS data. Children and adolescents younger than 19 years for whom information on at least 1 H1N1 influenza vaccine was present in NYSIIS. Median time to administer vaccines to children and adolescents younger than 19 years by December 31, 2009, by county; venue of H1N1 vaccine administration (local health department [LHD] or private medical provider); comparison of immunization-seeking behavior for routine childhood vaccinations and H1N1 vaccine. A total of 459 189 first or only doses of H1N1 influenza vaccine were recorded in NYSIIS as being administered to New York State, outside of New York City, children aged less than 19 years, between October 2, 2009, and December 31, 2009. Overall, LHD administered 31% of H1N1 vaccine doses; in counties having population less than 100,000, LHD administered 63% of H1N1 doses compared with 23% in counties having population more than 100,000. Time to median administration was faster for LHD in smaller counties and similar for LHD and private medical providers in larger counties. Children who always received routine childhood immunizations either within or outside of their county of residence often had the same practice for H1N1 vaccine, with 85% of children following these patterns. Children who did not follow these patterns were more likely to receive H1N1 influenza vaccine through LHD. Local health departments were able to rapidly administer large quantities of H1N1 influenza vaccine, and patterns of health care seeking relying on increased use of LHD needs to be further studied for future public health emergency planning.

  16. Pandemic (H1N1 2009 Influenza Virus Infection in A Survivor who has recovered from severe H7N9 Virus Infection, China

    Directory of Open Access Journals (Sweden)

    Shan-Hui Chen

    2016-10-01

    Full Text Available We firstly report a patient who presented with severe complications after infection with influenza A(H1N1 pdm2009, more than one year after recovery from severe H7N9 virus infections. The population of patients who recovered from severe H7N9 infections might be at a higher risk to suffer severe complications after seasonal influenza infections, and they should be included in the high-risk populations recommended to receive seasonal influenza vaccination.

  17. Case-based reported mortality associated with laboratory-confirmed influenza A(H1N1 2009 virus infection in the Netherlands: the 2009-2010 pandemic season versus the 2010-2011 influenza season

    Directory of Open Access Journals (Sweden)

    Timen Aura

    2011-10-01

    Full Text Available Abstract Background In contrast to seasonal influenza epidemics, where the majority of deaths occur amongst elderly, a considerable part of the 2009 pandemic influenza related deaths concerned relatively young people. In the Netherlands, all deaths associated with laboratory-confirmed influenza A(H1N1 2009 virus infection had to be notified, both during the 2009-2010 pandemic season and the 2010-2011 influenza season. To assess whether and to what extent pandemic mortality patterns were reverting back to seasonal patterns, a retrospective analyses of all notified fatal cases associated with laboratory-confirmed influenza A(H1N1 2009 virus infection was performed. Methods The notification database, including detailed information about the clinical characteristics of all notified deaths, was used to perform a comprehensive analysis of all deceased patients with a laboratory-confirmed influenza A(H1N1 2009 virus infection. Characteristics of the fatalities with respect to age and underlying medical conditions were analysed, comparing the 2009-2010 pandemic and the 2010-2011 influenza season. Results A total of 65 fatalities with a laboratory-confirmed influenza A(H1N1 2009 virus infection were notified in 2009-2010 and 38 in 2010-2011. During the pandemic season, the population mortality rates peaked in persons aged 0-15 and 55-64 years. In the 2010-2011 influenza season, peaks in mortality were seen in persons aged 0-15 and 75-84 years. During the 2010-2011 influenza season, the height of first peak was lower compared to that during the pandemic season. Underlying immunological disorders were more common in the pandemic season compared to the 2010-2011 season (p = 0.02, and cardiovascular disorders were more common in the 2010-2011 season (p = 0.005. Conclusions The mortality pattern in the 2010-2011 influenza season still resembled the 2009-2010 pandemic season with a peak in relatively young age groups, but concurrently a clear shift toward

  18. Pneumococcal Pneumonia and Pandemic H1N1

    Centers for Disease Control (CDC) Podcasts

    2012-06-06

    Dr. George Nelson, a CDC medical officer, discusses the relationship between pneumococcal pneumonia and Pandemic H1N1.  Created: 6/6/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 6/6/2012.

  19. Real-time forecasting of an epidemic using a discrete time stochastic model: a case study of pandemic influenza (H1N1-2009

    Directory of Open Access Journals (Sweden)

    Nishiura Hiroshi

    2011-02-01

    Full Text Available Abstract Background Real-time forecasting of epidemics, especially those based on a likelihood-based approach, is understudied. This study aimed to develop a simple method that can be used for the real-time epidemic forecasting. Methods A discrete time stochastic model, accounting for demographic stochasticity and conditional measurement, was developed and applied as a case study to the weekly incidence of pandemic influenza (H1N1-2009 in Japan. By imposing a branching process approximation and by assuming the linear growth of cases within each reporting interval, the epidemic curve is predicted using only two parameters. The uncertainty bounds of the forecasts are computed using chains of conditional offspring distributions. Results The quality of the forecasts made before the epidemic peak appears largely to depend on obtaining valid parameter estimates. The forecasts of both weekly incidence and final epidemic size greatly improved at and after the epidemic peak with all the observed data points falling within the uncertainty bounds. Conclusions Real-time forecasting using the discrete time stochastic model with its simple computation of the uncertainty bounds was successful. Because of the simplistic model structure, the proposed model has the potential to additionally account for various types of heterogeneity, time-dependent transmission dynamics and epidemiological details. The impact of such complexities on forecasting should be explored when the data become available as part of the disease surveillance.

  20. 1918 pandemic H1N1 DNA vaccine protects ferrets against 2007 H1N1 virus infection

    DEFF Research Database (Denmark)

    Bragstad, Karoline; Martel, Cyril Jean-Marie; Aasted, Bent

    of the H1N1 pandemic virus from 1918 induce protection in ferrets against infection with a H1N1 (A/New Caledonia/20/99(H1N1)) virus which was included in the conventional vaccine for the 2006-2007 season. The viruses are separated by a time interval of 89 years and differ by 21.2% in the HA1 protein...

  1. International collaboration to assess the risk of Guillain Barre Syndrome following Influenza A (H1N1) 2009 monovalent vaccines

    NARCIS (Netherlands)

    Dodd, Caitlin N.; Romio, Silvana A.; Black, Steven; Vellozzi, Claudia; Andrews, Nick; Sturkenboom, Miriam; Zuber, Patrick; Hua, Wei; Bonhoeffer, Jan; Buttery, Jim; Crawford, Nigel; Deceuninck, Genevieve; de Vries, Corinne; De Wals, Philippe; Gutierrez-Gimeno, M. Victoria; Heijbel, Harald; Hughes, Hayley; Hur, Kwan; Hviid, Anders; Kelman, Jeffrey; Kilpi, Tehri; Chuang, S. K.; Macartney, Kristine; Rett, Melisa; Lopez-Callada, Vesta Richardson; Salmon, Daniel; Sanchez, Francisco Gimenez; Sanz, Nuria; Silverman, Barbara; Storsaeter, Jann; Thirugnanam, Umapathi; van der Maas, Nicoline; Yih, Katherine; Zhang, Tao; Izurieta, Hector

    2013-01-01

    Background: The global spread of the 2009 novel pandemic influenza A (H1N1) virus led to the accelerated production and distribution of monovalent 2009 Influenza A (H1N1) vaccines (pH1N1). This pandemic provided the opportunity to evaluate the risk of Guillain-Barre syndrome (GBS), which has been an

  2. Stability and infectivity of novel pandemic influenza A (H1N1) virus in blood-derived matrices under different storage conditions.

    Science.gov (United States)

    Wang, Xue; Zoueva, Olga; Zhao, Jiangqin; Ye, Zhiping; Hewlett, Indira

    2011-12-22

    Influenza A virus has been detected in the blood of some infected individuals, and may pose a safety concern for collection, handling and transport of specimens for epidemiological and public health investigations if infectious virus is present in samples. Furthermore the effect of storage on virus stability and infectivity has not been well studied. We examined the stability of novel pandemic influenza A (H1N1) virus RNA when the virus was stored in phosphate buffered saline (PBS), plasma, or buffy coated blood at either room temperature or 4°C using a sensitive Taqman RT-PCR assay. We also investigated virus infectivity using the EID(50) assay when virus was stored in PBS, plasma, or buffy coats isolated from blood at 4°C. Viral RNA stability was affected by the matrix used for storage. The recovery of viral RNA was highest when virus was stored in PBS with lower amounts being recovered from plasma and buffy coats at either room temperature or 4°C. Incubation time did not appear to be a major factor for viral RNA stability, although there was gradual decline after longer periods post-incubation. Both sample matrix and incubation time affected virus infectivity. The decay in virus infectivity was greatest in PBS followed by buffy coats and plasma. Virus infectivity was abolished in buffy coats at day 20 post-incubation when virus concentrations were low. These data indicate that encapsidated viral RNA was stable overall in all three liquid matrices at room temperature or 4°C although it was most stable in PBS; virus infectivity in buffy coats at 4°C decayed in a time dependent manner while it remained unchanged in plasma. These findings have implications for storage, handling and transport of blood derived samples from influenza patients for epidemiological and laboratory investigations. It should be noted that there is little known about influenza viremia, and whether influenza viruses can be transmitted by blood or blood derived samples.

  3. Stability and infectivity of novel pandemic influenza A (H1N1 virus in blood-derived matrices under different storage conditions

    Directory of Open Access Journals (Sweden)

    Wang Xue

    2011-12-01

    Full Text Available Abstract Background Influenza A virus has been detected in the blood of some infected individuals, and may pose a safety concern for collection, handling and transport of specimens for epidemiological and public health investigations if infectious virus is present in samples. Furthermore the effect of storage on virus stability and infectivity has not been well studied. Methods We examined the stability of novel pandemic influenza A (H1N1 virus RNA when the virus was stored in phosphate buffered saline (PBS, plasma, or buffy coated blood at either room temperature or 4°C using a sensitive Taqman RT-PCR assay. We also investigated virus infectivity using the EID50 assay when virus was stored in PBS, plasma, or buffy coats isolated from blood at 4°C. Results Viral RNA stability was affected by the matrix used for storage. The recovery of viral RNA was highest when virus was stored in PBS with lower amounts being recovered from plasma and buffy coats at either room temperature or 4°C. Incubation time did not appear to be a major factor for viral RNA stability, although there was gradual decline after longer periods post-incubation. Both sample matrix and incubation time affected virus infectivity. The decay in virus infectivity was greatest in PBS followed by buffy coats and plasma. Virus infectivity was abolished in buffy coats at day 20 post-incubation when virus concentrations were low. Conclusion These data indicate that encapsidated viral RNA was stable overall in all three liquid matrices at room temperature or 4°C although it was most stable in PBS; virus infectivity in buffy coats at 4°C decayed in a time dependent manner while it remained unchanged in plasma. These findings have implications for storage, handling and transport of blood derived samples from influenza patients for epidemiological and laboratory investigations. It should be noted that there is little known about influenza viremia, and whether influenza viruses can be

  4. Cross-protection against European swine influenza viruses in the context of infection immunity against the 2009 pandemic H1N1 virus: studies in the pig model of influenza.

    Science.gov (United States)

    Qiu, Yu; De Hert, Karl; Van Reeth, Kristien

    2015-09-24

    Pigs are natural hosts for the same influenza virus subtypes as humans and are a valuable model for cross-protection studies with influenza. In this study, we have used the pig model to examine the extent of virological protection between a) the 2009 pandemic H1N1 (pH1N1) virus and three different European H1 swine influenza virus (SIV) lineages, and b) these H1 viruses and a European H3N2 SIV. Pigs were inoculated intranasally with representative strains of each virus lineage with 6- and 17-week intervals between H1 inoculations and between H1 and H3 inoculations, respectively. Virus titers in nasal swabs and/or tissues of the respiratory tract were determined after each inoculation. There was substantial though differing cross-protection between pH1N1 and other H1 viruses, which was directly correlated with the relatedness in the viral hemagglutinin (HA) and neuraminidase (NA) proteins. Cross-protection against H3N2 was almost complete in pigs with immunity against H1N2, but was weak in H1N1/pH1N1-immune pigs. In conclusion, infection with a live, wild type influenza virus may offer substantial cross-lineage protection against viruses of the same HA and/or NA subtype. True heterosubtypic protection, in contrast, appears to be minimal in natural influenza virus hosts. We discuss our findings in the light of the zoonotic and pandemic risks of SIVs.

  5. H1N1 pandemic preparedness and business continuity plan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-10-15

    SaskPower's H1N1 pandemic preparedness and business continuity plan was designed to prepare SaskPower employees for elevated levels of absenteeism during a potential pandemic. Emergency management and business continuity will be facilitated if critical duties and essential services are maintained without interruption. A layered approach was used to develop a range of response measures designed to meet a range of possible pandemic threats. The plan identified essential activities, tasks and functions and outlined methods of mitigating supply disruptions and possible shortages. Methods of minimizing illness in employees were discussed, as well as methods of maintaining a safe and secure work environment. The measures were developed in accordance with the World Health Organization (WHO) 6 phases of pandemic alert. The plan was also designed to be read by SaskPower's key suppliers in order to ensure their pandemic readiness. 5 tabs.

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

    Science.gov (United States)

    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.

  7. (H1N1) Influenza in Saurashtra, India

    African Journals Online (AJOL)

    Mexico in April, 2009,[1] and then in United States (US).[2,3]. This was originally ... duration of hospital stay of such patients was 2‑32 days. All admitted A (H1N1) .... Because of limited resources, only 2009 A (H1N1) influenza virus was tested ...

  8. A Pandemic Influenza Preparedness Study: Use of Energetic Methods to Decontaminate Filtering Facepiece Respirators Contaminated with H1N1 Aerosols and Droplets (POSTPRINT)

    Science.gov (United States)

    2012-06-01

    the Occupational Safety and Health Ad- ministration ( OSHA ) and the Centers for Disease Control and Prevention (CDC) to recommend that HCWs wear a...unique feature of the present study is the con - trolled contamination of FFRs with H1N1 influenza us- ing aerosol methods, which provide a radically...components can pro - tect the virus from some decontamination technolo- gies. In the droplet challenge, the droplets do not dry completely, but land on

  9. Reasons for Low Pandemic H1N1 2009 Vaccine Acceptance within a College Sample

    Directory of Open Access Journals (Sweden)

    Russell D. Ravert

    2012-01-01

    Full Text Available This study examined health beliefs associated with novel influenza A (H1N1 immunization among US college undergraduates during the 2009-2010 pandemic. Undergraduates (ages 18–24 years from a large Midwestern University were invited to complete an online survey during March, 2010, five months after H1N1 vaccines became available. Survey items measured H1N1 vaccine history and H1N1-related attitudes based on the health belief literature. Logistic regression was used to identify attitudes associated with having received an H1N1 vaccine, and thematic analysis of student comments was conducted to further understand influences on vaccine decisions. Among the 296 students who participated in the survey, 15.2% reported having received an H1N1 vaccine. In regression analysis, H1N1 immunization was associated with seasonal flu vaccine history, perceived vaccine effectiveness, perceived obstacles to vaccination, and vaccine safety concerns. Qualitative results illustrate the relationship of beliefs to vaccine decisions, particularly in demonstrating that students often held concerns that vaccine could cause H1N1 or side effects. Vaccine safety, efficacy, and obstacles to immunization were major considerations in deciding whether to accept the H1N1 pandemic vaccine. Therefore, focusing on those aspects might be especially useful in future vaccine efforts within the college population.

  10. The influence of social-cognitive factors on personal hygiene practices to protect against influenzas: using modelling to compare avian A/H5N1 and 2009 pandemic A/H1N1 influenzas in Hong Kong.

    Science.gov (United States)

    Liao, Qiuyan; Cowling, Benjamin J; Lam, Wendy Wing Tak; Fielding, Richard

    2011-06-01

    Understanding population responses to influenza helps optimize public health interventions. Relevant theoretical frameworks remain nascent. To model associations between trust in information, perceived hygiene effectiveness, knowledge about the causes of influenza, perceived susceptibility and worry, and personal hygiene practices (PHPs) associated with influenza. Cross-sectional household telephone surveys on avian influenza A/H5N1 (2006) and pandemic influenza A/H1N1 (2009) gathered comparable data on trust in formal and informal sources of influenza information, influenza-related knowledge, perceived hygiene effectiveness, worry, perceived susceptibility, and PHPs. Exploratory factor analysis confirmed domain content while confirmatory factor analysis was used to evaluate the extracted factors. The hypothesized model, compiled from different theoretical frameworks, was optimized with structural equation modelling using the A/H5N1 data. The optimized model was then tested against the A/H1N1 dataset. The model was robust across datasets though corresponding path weights differed. Trust in formal information was positively associated with perceived hygiene effectiveness which was positively associated with PHPs in both datasets. Trust in formal information was positively associated with influenza worry in A/H5N1 data, and with knowledge of influenza cause in A/H1N1 data, both variables being positively associated with PHPs. Trust in informal information was positively associated with influenza worry in both datasets. Independent of information trust, perceived influenza susceptibility associated with influenza worry. Worry associated with PHPs in A/H5N1 data only. Knowledge of influenza cause and perceived PHP effectiveness were associated with PHPs. Improving trust in formal information should increase PHPs. Worry was significantly associated with PHPs in A/H5N1.

  11. La influenza A (H1N1: estado actual del conocimiento Influenza A (H1N1 virus: current information

    Directory of Open Access Journals (Sweden)

    Laura Margarita González Valdés

    2010-03-01

    Full Text Available Se revisó la bibliografía actualizada sobre el tema a partir de los principales buscadores, y reuniones internacionales realizadas sobre la pandemia de la influenza A (H1N1. Se tratan los aspectos relacionados con la historia, la aparición de la pandemia, la biología de la enfermedad, la epidemiología, el cuadro clínico, el tratamiento y el pronóstico y la prevención. La gripe A (H1N1 es una pandemia causada por una variante nueva del virus de la Influenza A que ha sufrido cambios antigénicos en la hemaglutinina y la neuraminidasa. Esto hace que la población sea altamente vulnerable a la infección y produce una sobrecarga temporal enorme a los servicios de salud. El virus se trasmite como otros virus Influenza. Su letalidad es similar a la de la influenza estacional, pero puede incrementarse en personas con factores de riesgo y en adultos jóvenes sanos. El asma y el embarazo parecen ser condiciones de base importantes para incrementar la severidad de la infección. Puede existir cierta protección por inmunidad cruzada con cepas que circularon en el pasado. El espectro clínico va desde personas asintomáticas hasta las formas graves que requieren internación en cuidados intensivos, con rápido deterioro hasta llegar a la insuficiencia respiratoria en un plazo de 24 horas. La vacunación durante la pandemia no parece ser suficientemente efectiva. Son necesarios antivirales (oseltamivir y zanamivir, y las medidas preventivas higiénico-sanitarias son muy eficaces.An updated review using the main search motors and international meetings already celebrated related to Influenza A H1N1 pandemics. Items related to the history, the appearance of the pandemics, the biology of the disease, its epidemiology, clinics, treatment, prognosis and prevention. Grippe A H1N1 is a pandemic caused by a new variant of the Influenza A virus that has suffered antigenic changes in haemaglutinin and neuraminidase. This turns populations more susceptible to

  12. Effectiveness of a MF-59™-adjuvanted pandemic influenza vaccine to prevent 2009 A/H1N1 influenza-related hospitalisation; a matched case-control study

    Directory of Open Access Journals (Sweden)

    van der Sande Marianne AB

    2011-07-01

    Full Text Available Abstract Background During the 2009 influenza A/H1N1 pandemic, adjuvanted influenza vaccines were used for the first time on a large scale. Results on the effectiveness of the vaccines in preventing 2009 influenza A/H1N1-related hospitalisation are scanty and varying. Methods We conducted a matched case-control study in individuals with an indication for vaccination due to underlying medical conditions and/or age ≥ 60 years in the Netherlands. Cases were patients hospitalised with laboratory-confirmed 2009 A/H1N1 influenza infection between November 16, 2009 and January 15, 2010. Controls were matched to cases on age, sex and type of underlying medical condition(s and drawn from an extensive general practitioner network. Conditional logistic regression was used to estimate the vaccine effectiveness (VE = 1 - OR. Different sensitivity analyses were used to assess confounding by severity of underlying medical condition(s and the effect of different assumptions for missing dates of vaccination. Results 149 cases and 28,238 matched controls were included. It was estimated that 22% of the cases and 28% of the controls received vaccination more than 7 days before the date of onset of symptoms in cases. A significant number of breakthrough infections were observed. The VE was estimated at 19% (95%CI -28-49. After restricting the analysis to cases with controls suffering from severe underlying medical conditions, the VE was 49% (95%CI 16-69. Conclusions The number of breakthrough infections, resulting in modest VE estimates, suggests that the MF-59™ adjuvanted vaccine may have had only a limited impact on preventing 2009 influenza A/H1N1-related hospitalisation in this setting. As the main aim of influenza vaccination programmes is to reduce severe influenza-related morbidity and mortality from influenza in persons at high risk of complications, a more effective vaccine, or additional preventive measures, are needed.

  13. Influenza A(H1N1)pdm09 in critically ill children admitted to a ...

    African Journals Online (AJOL)

    tes. Fig. 1. The prevalence of seasonal and pandemic H1N1 (pH1N1) influenza A at RCWMCH and ... Full approval for the study was obtained from the Human Research ... respiratory virus infection, had not received prophylactic oseltamivir,.

  14. Obstetricians and the 2009-2010 H1N1 vaccination effort: implications for future pandemics.

    Science.gov (United States)

    Clark, Sarah J; Cowan, Anne E; Wortley, Pascale M

    2013-09-01

    Our objective was to describe the experiences of obstetricians during the 2009-2010 H1N1 vaccination campaign in order to identify possible improvements for future pandemic situations. We conducted a cross-sectional mail survey of a national random sample of 4,000 obstetricians, fielded in Summer 2010. Survey items included availability, recommendation, and patient acceptance of H1N1 vaccine; prioritization of H1N1 vaccine when supply was limited; problems with H1N1 vaccination; and likelihood of providing vaccine during a future influenza pandemic. Response rate was 66 %. Obstetricians strongly recommended H1N1 vaccine during the second (85 %) and third (86 %) trimesters, and less often during the first trimester (71 %) or the immediate postpartum period (76 %); patient preferences followed a similar pattern. H1N1 vaccine was typically available in outpatient obstetrics clinics (80 %). Overall vaccine supply was a major problem for 30 % of obstetricians, but few rated lack of thimerosal-free vaccine as a major problem (12 %). Over half of obstetricians had no major problems with the H1N1 vaccine campaign. Based on this experience, 74 % would be "very likely" and 12 % "likely" to provide vaccine in the event of a future influenza pandemic. Most obstetricians strongly recommended H1N1 vaccine, had few logistical problems beyond limited vaccine supply, and are willing to vaccinate in a future pandemic. Addressing concerns about first-trimester vaccination, developing guidance for prioritization of vaccine in the event of severe supply constraints, and continued facilitation of the logistical aspects of vaccination should be emphasized in future influenza pandemics.

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

    Science.gov (United States)

    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.

  16. Clinical aspects of influenza A (H1N1 in HIV-infected individuals in São Paulo during the pandemic of 2009

    Directory of Open Access Journals (Sweden)

    Rosana Del Bianco

    Full Text Available OBJECTIVE: To describe the clinical aspects of H1N1 among HIV coinfected patients seen at a reference center for AIDS treatment in São Paulo, Brazil. Design: Observational and prospective cohort study. METHODS: Descriptive study of clinical and laboratory investigation of HIV-infected patients with confirmed diagnosis of influenza A (H1N1 in 2009. We analyzed patients monitored in CRT/DST/AIDS, a specialized service for people living with HIV, located in São Paulo, Brazil. RESULTS: 108 individuals presented with symptoms of H1N1 infection at the CRT DST/AIDS in 2009. Eighteen patients (16.7% had confirmation of the diagnosis of influenza A. Among the confirmed cases, ten (55.6% were hospitalized and eight (44.4% were outpatients. Dyspnea was present in nine patients (50%, hemoptysis in three (16%. Six patients (60% required therapy with supplemental oxygen. All patients had good clinical outcomes and none died. CONCLUSIONS: In our hospital, the symptoms that led patients to seek medical care were similar to the common flu. Hospital admission and the early introduction of antibiotics associated with oseltamivir may have been the cause of the favorable outcome of our cases.

  17. National surveillance of pandemic influenza A(H1N1) infection-related admissions to intensive care units during the 2009-10 winter peak in Denmark: two complementary approaches

    DEFF Research Database (Denmark)

    Gubbels, S; Perner, A; Valentiner-Branth, Palle

    2010-01-01

    close contact with a laboratory-confirmed case. Aggregate numbers of cases were reported weekly: during weeks 48-51 (the peak), reporting was daily. The case-based reports contained demographic and clinical information. The aggregate surveillance registered 93 new cases, the case-based surveillance 61......Surveillance of 2009 pandemic influenza A(H1N1) in Denmark was enhanced during the 2009–10 winter season with a system monitoring the burden of the pandemic on intensive care units (ICUs), in order to inform policymakers and detect shortages in ICUs in a timely manner. Between week 46 of 2009...... and week 11 of 2010, all 36 relevant Danish ICUs reported in two ways: aggregate data were reported online and case-based data on paper. Cases to be reported were defined as patients admitted to an ICU with laboratory-confirmed 2009 pandemic influenza A(H1N1) infection or clinically suspected illness after...

  18. Inpatient capacity at children's hospitals during pandemic (H1N1) 2009 outbreak, United States.

    Science.gov (United States)

    Sills, Marion R; Hall, Matthew; Fieldston, Evan S; Hain, Paul D; Simon, Harold K; Brogan, Thomas V; Fagbuyi, Daniel B; Mundorff, Michael B; Shah, Samir S

    2011-09-01

    Quantifying how close hospitals came to exhausting capacity during the outbreak of pandemic influenza A (H1N1) 2009 can help the health care system plan for more virulent pandemics. This ecologic analysis used emergency department (ED) and inpatient data from 34 US children's hospitals. For the 11-week pandemic (H1N1) 2009 period during fall 2009, inpatient occupancy reached 95%, which was lower than the 101% occupancy during the 2008-09 seasonal influenza period. Fewer than 1 additional admission per 10 inpatient beds would have caused hospitals to reach 100% occupancy. Using parameters based on historical precedent, we built 5 models projecting inpatient occupancy, varying the ED visit numbers and admission rate for influenza-related ED visits. The 5 scenarios projected median occupancy as high as 132% of capacity. The pandemic did not exhaust inpatient bed capacity, but a more virulent pandemic has the potential to push children's hospitals past their maximum inpatient capacity.

  19. Maternal and neonatal outcomes among pregnant women with 2009 pandemic influenza A(H1N1 illness in Florida, 2009-2010: a population-based cohort study.

    Directory of Open Access Journals (Sweden)

    Timothy J Doyle

    Full Text Available Pregnant women have been identified as a high risk group for severe illness with 2009 pandemic influenza A(H1N1 virus infection (pH1N1. Obesity has also been identified as a risk factor for severe illness, though this has not been thoroughly assessed among pregnant women. The objectives of this study were to provide risk estimates for adverse maternal and neonatal outcomes associated with pH1N1 illness during pregnancy and to assess the role of obesity in these outcomes.We established a retrospective population-based cohort of all live births occurring in Florida during the first 15 months of the pandemic. Illness with pH1N1 during pregnancy was ascertained through record linkage with the Florida state notifiable disease surveillance database. Data from the birth record, including pre-pregnancy body mass index, were analyzed to assess risk of adverse outcomes associated with pH1N1 illness.A total of 194 women were identified through surveillance with pH1N1 illness during pregnancy. Children born to women with pH1N1 illness during pregnancy were at increased risk for low birth weight [OR (95%CI: 1.78 (1.11-2.860], premature birth [2.21 (1.47-3.330], and infant death [4.46 (1.80-11.00], after adjusting for other factors. Women with pH1N1 illness during pregnancy were at increased risk for severe outcomes including admission to an intensive care unit. Obesity was an observed risk factor, both for the more severe pH1N1 illness detected through surveillance, and for severe maternal outcomes.Case-patients in this analysis likely represent the most severely ill subset of all women infected with pH1N1 during pregnancy, limiting the generalizability of these findings to more severely ill patients rather than influenza infection in general. Nevertheless, these results suggest that more severe pH1N1 illness during pregnancy is associated with adverse neonatal outcomes and that pregnant women should continue to be targeted for appropriate prophylaxis and

  20. The impact of alternative diagnoses on the utility of influenza-like illness case definition to detect the 2009 H1N1 pandemic.

    Science.gov (United States)

    Rumoro, Dino P; Bayram, Jamil D; Silva, Julio C; Shah, Shital C; Hallock, Marilyn M; Gibbs, Gillian S; Waddell, Michael J

    2012-01-01

    To investigate the impact of excluding cases with alternative diagnoses on the sensitivity and specificity of the Centers for Disease Control and Prevention's (CDC) influenza-like illness (ILI) case definition in detecting the 2009 H1N1 influenza, using Geographic Utilization of Artificial Intelligence in Real-Time for Disease Identification and Alert Notification, a disease surveillance system. Retrospective cross-sectional study design. Emergency department of an urban tertiary care academic medical center. 1,233 ED cases, which were tested for respiratory viruses from September 5, 2009 to May 5, 2010. The main outcome measures were positive predictive value, negative predictive value, sensitivity, specificity, and accuracy of the ILI case definition (both including and excluding alternative diagnoses) to detect H1N1. There was a significant decrease in sensitivity (chi2 = 9.09, p < 0.001) and significant improvement in specificity (chi2 = 179, p < 0.001), after excluding cases with alternative diagnoses. When early detection of an influenza epidemic is of prime importance, pursuing alternative diagnoses as part of CDC's ILI case definition may not be warranted for public health reporting due to the significant decrease in sensitivity, in addition to the resources required for detecting these alternative diagnoses.

  1. Pandemic 2009 Influenza A (H1N1 virus infection in cancer and hematopoietic stem cell transplant recipients; a multicenter observational study. [v1; ref status: indexed, http://f1000r.es/4bi

    Directory of Open Access Journals (Sweden)

    Maria Cecilia Dignani

    2014-09-01

    Full Text Available Background: During March 2009 a novel Influenza A virus emerged in Mexico. We describe the clinical picture of the pandemic Influenza A (H1N1 Influenza in cancer patients during the 2009 influenza season. Methods: Twelve centers participated in a multicenter retrospective observational study of cancer patients with confirmed infection with the 2009 H1N1 Influenza A virus (influenza-like illness or pneumonia plus positive PCR for the 2009 H1N1 Influenza A virus  in respiratory secretions. Clinical data were obtained by retrospective chart review and analyzed.  Results: From May to August 2009, data of 65 patients were collected. Median age was 51 years, 57 % of the patients were female. Most patients (47 had onco-hematological cancers and 18 had solid tumors. Cancer treatment mainly consisted of chemotherapy (46, or stem cell transplantation (SCT (16. Only 19 of 64 patients had received the 2009 seasonal Influenza vaccine. Clinical presentation included pneumonia (43 and upper respiratory tract infection (22. Forty five of 58 ambulatory patients were admitted. Mechanical ventilation was required in 12 patients (18%. Treatment included oseltamivir monotherapy or in combination with amantadine for a median of 7 days. The global 30-day mortality rate was 18%. All 12 deaths were among the non-vaccinated patients. No deaths were observed among the 19 vaccinated patients. Oxygen saturation <96% at presentation was a predictor of mortality (OR 19.5; 95%CI: 2.28 to 165.9. Conclusions: In our cancer patient population, the pandemic 2009 Influenza A (H1N1 virus was associated with high incidence of pneumonia (66%, and 30-day mortality (18.5%. Saturation <96% was significantly associated with death. No deaths were observed among vaccinated patients.

  2. Pandemic (H1N1) 2009 Outbreak at Camp for Children with Hematologic and Oncologic Conditions

    Science.gov (United States)

    Morrison, Cori; Maurtua-Neumann, Paola; Myint, Myo Thwin; Drury, Stacy S.

    2011-01-01

    An outbreak of influenza A pandemic (H1N1) 2009 occurred among campers and staff at a summer camp attended by children with hematologic and oncologic conditions. The overall attack rate was 36% and was highest among children and adolescents (43%), persons with cancer (48%), and persons with sickle cell disease (82%). PMID:21192861

  3. Pandemic influenza 1918 H1N1 and 1968 H3N2 DNA vaccines induce cross-reactive immunity in ferrets against infection with viruses drifted for decades

    DEFF Research Database (Denmark)

    Bragstad, Karoline; Martel, Cyril; Thomsen, Joakim S.

    2011-01-01

    Please cite this paper as: Bragstad et al. (2010) Pandemic influenza 1918 H1N1 and 1968 H3N2 DNA vaccines induce cross-reactive immunity in ferrets against infection with viruses drifted for decades. Influenza and Other Respiratory Viruses 5(1), 13-23. Background Alternative influenza vaccines...... and vaccine production forms are needed as the conventional protein vaccines do not induce broad cross-reactivity against drifted strains. Furthermore, fast vaccine production is especially important in a pandemic situation, and broader vaccine reactivity would diminish the need for frequent change...... in the vaccine formulations. Objective In this study, we compared the ability of pandemic influenza DNA vaccines to induce immunity against distantly related strains within a subtype with the immunity induced by conventional trivalent protein vaccines against homologous virus challenge. Methods Ferrets were...

  4. Altered specificity of single-chain antibody fragments bound to pandemic H1N1-2009 influenza virus after conversion of the phage-bound to the soluble form

    Directory of Open Access Journals (Sweden)

    Kaku Yoshihiro

    2012-09-01

    Full Text Available Abstract Background In 2009, a novel influenza A/H1N1 virus (H1N1pdm quickly spread worldwide and co-circulated with then-existing seasonal H1N1 virus (sH1N1. Distinguishing between these 2 viruses was necessary to better characterize the epidemiological properties of the emergent virus, including transmission patterns, pathogenesis, and anti-influenza drug resistance. This situation prompted us to develop a point-of-care virus differentiation system before entering the 2009–2010 influenza season. Aiming to establish H1N1pdm-specific detection tools rapidly, we employed phage display libraries to select H1N1pdm-specific single-chain variable fragments (scFvs. Findings Human single-fold scFv libraries (Tomlinson I + J underwent selection for the ability to bind H1N1pdm virus particles. Three rounds of panning brought 1152 phage-bound scFvs, of which 58 clones reacted with H1N1pdm specifically or preferentially over sH1N1 in an enzyme-linked immunosorbent assay (ELISA. After conversion of the scFvs to soluble form, 7 clones demonstrating high/stable expression were finally obtained. However, all the soluble scFvs except No. 29 were found to have lost their specificity/preference for H1N1pdm in ELISA. The specificity/preference of No. 29 was also confirmed by immunofluorescence assay and immunoprecipitation, and the viral nucleoprotein was identified by ELISA as its target protein. The change in specificity associated with scFv conversion from phage-bound to soluble form could be due to loss of phage scaffold pIII protein, which likely provides structural support for the scFv antigen-binding site. It is also possible that the similar antigenic properties of H1N1pdm and sH1N1 led to the observed alterations in scFv specificity. Discussion Using a phage display library, we obtained 7 soluble scFv clones reactive against H1N1pdm; however, only 1 showed specificity/preference toward H1N1pdm. Our results confirmed that using phage display

  5. Nosocomial Pandemic (H1N1) 2009, United Kingdom, 2009–2010

    Science.gov (United States)

    Myles, Puja R.; Openshaw, Peter J.M.; Gadd, Elaine M.; Lim, Wei Shen; Semple, Malcolm G.; Read, Robert C.; Taylor, Bruce L.; McMenamin, James; Armstrong, Colin; Bannister, Barbara; Nicholson, Karl G.; Nguyen-Van-Tam, Jonathan S.

    2011-01-01

    To determine clinical characteristics of patients hospitalized in the United Kingdom with pandemic (H1N1) 2009, we studied 1,520 patients in 75 National Health Service hospitals. We characterized patients who acquired influenza nosocomially during the pandemic (H1N1) 2009 outbreak. Of 30 patients, 12 (80%) of 15 adults and 14 (93%) of 15 children had serious underlying illnesses. Only 12 (57%) of 21 patients who received antiviral therapy did so within 48 hours after symptom onset, but 53% needed escalated care or mechanical ventilation; 8 (27%) of 30 died. Despite national guidelines and standardized infection control procedures, nosocomial transmission remains a problem when influenza is prevalent. Health care workers should be routinely offered influenza vaccine, and vaccination should be prioritized for all patients at high risk. Staff should remain alert to the possibility of influenza in patients with complex clinical problems and be ready to institute antiviral therapy while awaiting diagnosis during influenza outbreaks. PMID:21470446

  6. High Level Antibody Response to Pandemic Influenza H1N1/09 Virus Is Associated With Interferon-Induced Transmembrane Protein-3 rs12252-CC in Young Adults

    Directory of Open Access Journals (Sweden)

    Ling Qin

    2018-05-01

    Full Text Available Background: The C allele of the interferon-induced transmembrane protein-3 (IFITM3 SNP rs12252, a common allele in South East Asia and China, is strongly associated with severe influenza infection. However, despite the high occurrence of rs12252-CC genotype in Chinese population (~25%, severe influenza infection is rare. The aim of study is to determine whether rs12252-CC individuals have pre-existing antibody responses to previous seasonal influenza infections.Cohort and Method: A total 99 young healthy volunteers (18–20 years were recruited and received an influenza seasonal Vaccination [A/Switzerland/9715293/2013(H3N2, A/California/7/2009 (pdm09H1N1 and B/Jeep/3073/2013-like virus (Flu-B]. Plasma and gDNA was isolated from each volunteer before, and 14, 28, 180, 360, and 540 days after vaccination. Additionally, 68 elderlies (>65 years were also recruited as a control group to compare the levels of antibodies at baseline between the young adults and the elderly. For each sample IFITM3 rs12252 genotype was determined and antibody levels in response to pdmH1N1, H3N2 and Influenza B infection were measured for each time point.Results: We found a significantly higher level of pre-existing antibodies to pandemic influenza H1N1/09 virus (pdm09H1N1 but not to H3N2 or FluB in CC donors in comparison with CT/TT donors prior to vaccination. No impact of IFITM3 genotype in boosting influenza specific antibodies in young adults within 1 year after receiving seasonal influenza vaccination was observed. In addition, there was no difference in pdm09H1N1 specific antibody levels observed in the elderly cohort between volunteers carrying different IFITM3 genotypes. Higher levels of antibodies to pdmH1N1 were observed in elderly CC carriers when compared to the young CC carriers, but this trend was not replicated in TT carriers.Conclusion:IFITM3-rs12252 CC carriers exhibit a high level of pre-existing immunity to pdm09H1N1 compared to TT carriers in the

  7. Pathogenesis of infection with 2009 pandemic H1N1 influenza virus in isogenic guinea pigs after intranasal or intratracheal inoculation.

    Science.gov (United States)

    Wiersma, Lidewij C M; Vogelzang-van Trierum, Stella E; van Amerongen, Geert; van Run, Peter; Nieuwkoop, Nella J; Ladwig, Mechtild; Banneke, Stefanie; Schaefer, Hubert; Kuiken, Thijs; Fouchier, Ron A M; Osterhaus, Albert D M E; Rimmelzwaan, Guus F

    2015-03-01

    To elucidate the pathogenesis and transmission of influenza virus, the ferret model is typically used. To investigate protective immune responses, the use of inbred mouse strains has proven invaluable. Here, we describe a study with isogenic guinea pigs, which would uniquely combine the advantages of the mouse and ferret models for influenza virus infection. Strain 2 isogenic guinea pigs were inoculated with H1N1pdm09 influenza virus A/Netherlands/602/09 by the intranasal or intratracheal route. Viral replication kinetics were assessed by determining virus titers in nasal swabs and respiratory tissues, which were also used to assess histopathologic changes and the number of infected cells. In all guinea pigs, virus titers peaked in nasal secretions at day 2 after inoculation. Intranasal inoculation resulted in higher virus excretion via the nose and higher virus titers in the nasal turbinates than intratracheal inoculation. After intranasal inoculation, infectious virus was recovered only from nasal epithelium; after intratracheal inoculation, it was recovered also from trachea, lung, and cerebrum. Histopathologic changes corresponded with virus antigen distribution, being largely limited to nasal epithelium for intranasally infected guinea pigs and more widespread in the respiratory tract for intratracheally infected guinea pigs. In summary, isogenic guinea pigs show promise as a model to investigate the role of humoral and cell-mediated immunities to influenza and their effect on virus transmission. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  8. Epidemiology of Travel-associated Pandemic (H1N1) 2009 Infection in 116 Patients, Singapore

    OpenAIRE

    Mukherjee, Pratik; Lim, Poh Lian; Chow, Angela; Barkham, Timothy; Seow, Eillyne; Win, Mar Kyaw; Chua, Arlene; Leo, Yee Sin; Chen, Mark I-Cheng

    2010-01-01

    In June 2009, during Singapore?s pandemic influenza plan containment phase, pandemic (H1N1) 2009 was introduced into the country through imported cases. To understand how travel patterns affected the initial outbreak, we examined epidemiologic and travel data for the first 116 case-patients admitted to Tan Tock Seng Hospital, Singapore, with travel-associated infection. Sixty-one percent and 54% of patients, respectively, met US Centers for Disease Control and Prevention and World Health Orga...

  9. H1N1 Influenza A hos mennesker og svin

    DEFF Research Database (Denmark)

    Larsen, Lars Erik

    2009-01-01

    Den nye pandemiske influenza A stamme H1N1 er hovedsagelig et nyt virus, som spredes mellem mennesker, men virusset er formodentlig opstået ved blanding af to svineinfluenza-virus og har derfor bibeholdt evnen til at kunne smitte fra mennesker til svin og fra svin til svin. Det er derfor vigtigt...

  10. Comparison of temporal and spatial dynamics of seasonal H3N2, pandemic H1N1 and highly pathogenic avian influenza H5N1 virus infections in ferrets.

    Directory of Open Access Journals (Sweden)

    Judith M A van den Brand

    Full Text Available Humans may be infected by different influenza A viruses--seasonal, pandemic, and zoonotic--which differ in presentation from mild upper respiratory tract disease to severe and sometimes fatal pneumonia with extra-respiratory spread. Differences in spatial and temporal dynamics of these infections are poorly understood. Therefore, we inoculated ferrets with seasonal H3N2, pandemic H1N1 (pH1N1, and highly pathogenic avian H5N1 influenza virus and performed detailed virological and pathological analyses at time points from 0.5 to 14 days post inoculation (dpi, as well as describing clinical signs and hematological parameters. H3N2 infection was restricted to the nose and peaked at 1 dpi. pH1N1 infection also peaked at 1 dpi, but occurred at similar levels throughout the respiratory tract. H5N1 infection occurred predominantly in the alveoli, where it peaked for a longer period, from 1 to 3 dpi. The associated lesions followed the same spatial distribution as virus infection, but their severity peaked between 1 and 6 days later. Neutrophil and monocyte counts in peripheral blood correlated with inflammatory cell influx in the alveoli. Of the different parameters used to measure lower respiratory tract disease, relative lung weight and affected lung tissue allowed the best quantitative distinction between the virus groups. There was extra-respiratory spread to more tissues--including the central nervous system--for H5N1 infection than for pH1N1 infection, and to none for H3N2 infection. This study shows that seasonal, pandemic, and zoonotic influenza viruses differ strongly in the spatial and temporal dynamics of infection in the respiratory tract and extra-respiratory tissues of ferrets.

  11. Design and Performance of the CDC Real-Time Reverse Transcriptase PCR Swine Flu Panel for Detection of 2009 A (H1N1) Pandemic Influenza Virus▿†‡

    Science.gov (United States)

    Shu, Bo; Wu, Kai-Hui; Emery, Shannon; Villanueva, Julie; Johnson, Roy; Guthrie, Erica; Berman, LaShondra; Warnes, Christine; Barnes, Nathelia; Klimov, Alexander; Lindstrom, Stephen

    2011-01-01

    Swine influenza viruses (SIV) have been shown to sporadically infect humans and are infrequently identified by the Influenza Division of the Centers for Disease Control and Prevention (CDC) after being received as unsubtypeable influenza A virus samples. Real-time reverse transcriptase PCR (rRT-PCR) procedures for detection and characterization of North American lineage (N. Am) SIV were developed and implemented at CDC for rapid identification of specimens from cases of suspected infections with SIV. These procedures were utilized in April 2009 for detection of human cases of 2009 A (H1N1) pandemic (pdm) influenza virus infection. Based on genetic sequence data derived from the first two viruses investigated, the previously developed rRT-PCR procedures were optimized to create the CDC rRT-PCR Swine Flu Panel for detection of the 2009 A (H1N1) pdm influenza virus. The analytical sensitivity of the CDC rRT-PCR Swine Flu Panel was shown to be 5 copies of RNA per reaction and 10−1.3∼−0.7 50% infectious doses (ID50) per reaction for cultured viruses. Cross-reactivity was not observed when testing human clinical specimens or cultured viruses that were positive for human seasonal A (H1N1, H3N2) and B influenza viruses. The CDC rRT-PCR Swine Flu Panel was distributed to public health laboratories in the United States and internationally from April 2009 until June 2010. The CDC rRT-PCR Swine Flu Panel served as an effective tool for timely and specific detection of 2009 A (H1N1) pdm influenza viruses and facilitated subsequent public health response implementation. PMID:21593260

  12. Monitoring the level of government trust, risk perception and intention of the general public to adopt protective measures during the influenza A (H1N1) pandemic in The Netherlands.

    Science.gov (United States)

    van der Weerd, Willemien; Timmermans, Daniëlle Rm; Beaujean, Desirée Jma; Oudhoff, Jurriaan; van Steenbergen, Jim E

    2011-07-19

    During the course of an influenza pandemic, governments know relatively little about the possibly changing influence of government trust, risk perception, and receipt of information on the public's intention to adopt protective measures or on the acceptance of vaccination. This study aims to identify and describe possible changes in and factors associated with public's intentions during the 2009 influenza A (H1N1) pandemic in the Netherlands. Sixteen cross-sectional telephone surveys were conducted (N = 8060) between April - November 2009. From these repeated measurements three consecutive periods were categorized based on crucial events during the influenza A (H1N1) pandemic. Time trends in government trust, risk perception, intention to adopt protective measures, and the acceptance of vaccination were analysed. Factors associated with an intention to adopt protective measures or vaccination were identified. Trust in the government was high, but decreased over time. During the course of the pandemic, perceived vulnerability and an intention to adopt protective measures increased. Trust and vulnerability were associated with an intention to adopt protective measures in general only during period one. Higher levels of intention to receive vaccination were associated with increased government trust, fear/worry, and perceived vulnerability. In periods two and three receipt of information was positively associated with an intention to adopt protective measures. Most respondents wanted to receive information about infection prevention from municipal health services, health care providers, and the media. The Dutch response to the H1N1 virus was relatively muted. Higher levels of trust in the government, fear/worry, and perceived vulnerability were all positively related to an intention to accept vaccination. Only fear/worry was positively linked to an intention to adopt protective measures during the entire pandemic. Risk and crisis communication by the government should

  13. Importance of background rates of disease in assessment of vaccine safety during mass immunisation with pandemic H1N1 influenza vaccines

    Science.gov (United States)

    Black, Steven; Eskola, Juhani; Siegrist, Claire-Anne; Halsey, Neal; MacDonald, Noni; Law, Barbara; Miller, Elizabeth; Andrews, Nick; Stowe, Julia; Salmon, Daniel; Vannice, Kirsten; Izurieta, Hector S; Akhtar, Aysha; Gold, Mike; Oselka, Gabriel; Zuber, Patrick; Pfeifer, Dina; Vellozzi, Claudia

    2010-01-01

    Because of the advent of a new influenza A H1N1 strain, many countries have begun mass immunisation programmes. Awareness of the background rates of possible adverse events will be a crucial part of assessment of possible vaccine safety concerns and will help to separate legitimate safety concerns from events that are temporally associated with but not caused by vaccination. We identified background rates of selected medical events for several countries. Rates of disease events varied by age, sex, method of ascertainment, and geography. Highly visible health conditions, such as Guillain-Barré syndrome, spontaneous abortion, or even death, will occur in coincident temporal association with novel influenza vaccination. On the basis of the reviewed data, if a cohort of 10 million individuals was vaccinated in the UK, 21·5 cases of Guillain-Barré syndrome and 5·75 cases of sudden death would be expected to occur within 6 weeks of vaccination as coincident background cases. In female vaccinees in the USA, 86·3 cases of optic neuritis per 10 million population would be expected within 6 weeks of vaccination. 397 per 1 million vaccinated pregnant women would be predicted to have a spontaneous abortion within 1 day of vaccination. PMID:19880172

  14. Risk of Guillain-Barré syndrome after exposure to pandemic influenza A(H1N1)pdm09 vaccination or infection: a Norwegian population-based cohort study.

    Science.gov (United States)

    Ghaderi, Sara; Gunnes, Nina; Bakken, Inger Johanne; Magnus, Per; Trogstad, Lill; Håberg, Siri Eldevik

    2016-01-01

    Vaccinations and infections are possible triggers of Guillain-Barré syndrome (GBS). However, studies on GBS after vaccinations during the influenza A(H1N1)pmd09 pandemic in 2009, show inconsistent results. Only few studies have addressed the role of influenza infection. We used information from national health data-bases with information on the total Norwegian population (N = 4,832,211). Cox regression analyses with time-varying covariates and self-controlled case series was applied. The risk of being hospitalized with GBS during the pandemic period, within 42 days after an influenza diagnosis or pandemic vaccination was estimated. There were 490 GBS cases during 2009-2012 of which 410 cases occurred after October 1, 2009 of which 46 new cases occurred during the peak period of the influenza pandemic. An influenza diagnosis was registered for 2.47% of the population and the vaccination coverage was 39.25%. The incidence rate ratio of GBS during the pandemic peak relative to other periods was 1.46 [95% confidence interval (CI) 1.08-1.98]. The adjusted hazard ratio (HR) of GBS within 42 days after a diagnosis of pandemic influenza was 4.89 (95% CI 1.17-20.36). After pandemic vaccination the adjusted HR was 1.11 (95% CI 0.51-2.43). Our results indicated that there was a significantly increased risk of GBS during the pandemic season and after pandemic influenza infection. However, vaccination did not increase the risk of GBS. The small number of GBS cases in this study warrants caution in the interpretation of the findings.

  15. Safety of pandemic H1N1 vaccines in children and adolescents.

    Science.gov (United States)

    Wijnans, Leonoor; de Bie, Sandra; Dieleman, Jeanne; Bonhoeffer, Jan; Sturkenboom, Miriam

    2011-10-06

    During the 2009 influenza A (H1N1) pandemic several pandemic H1N1 vaccines were licensed using fast track procedures, with relatively limited data on the safety in children and adolescents. Different extensive safety monitoring efforts were put in place to ensure timely detection of adverse events following immunization. These combined efforts have generated large amounts of data on the safety of the different pandemic H1N1 vaccines, also in children and adolescents. In this overview we shortly summarize the safety experience with seasonal influenza vaccines as a background and focus on the clinical and post marketing safety data of the pandemic H1N1 vaccines in children. We identified 25 different clinical studies including 10,505 children and adolescents, both healthy and with underlying medical conditions, between the ages of 6 months and 23 years. In addition, large monitoring efforts have resulted in large amounts of data, with almost 13,000 individual case reports in children and adolescents to the WHO. However, the diversity in methods and data presentation in clinical study publications and publications of spontaneous reports hampered the analysis of safety of the different vaccines. As a result, relatively little has been learned on the comparative safety of these pandemic H1N1 vaccines - particularly in children. It should be a collective effort to give added value to the enormous work going into the individual studies by adhering to available guidelines for the collection, analysis, and presentation of vaccine safety data in clinical studies and to guidance for the clinical investigation of medicinal products in the pediatric population. Importantly the pandemic has brought us the beginning of an infrastructure for collaborative vaccine safety studies in the EU, USA and globally. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Pandemic Swine-Origin H1N1 Influenza Virus Replicates to Higher Levels and Induces More Fever and Acute Inflammatory Cytokines in Cynomolgus versus Rhesus Monkeys and Can Replicate in Common Marmosets.

    Directory of Open Access Journals (Sweden)

    Petra Mooij

    Full Text Available The close immunological and physiological resemblance with humans makes non-human primates a valuable model for studying influenza virus pathogenesis and immunity and vaccine efficacy against infection. Although both cynomolgus and rhesus macaques are frequently used in influenza virus research, a direct comparison of susceptibility to infection and disease has not yet been performed. In the current study a head-to-head comparison was made between these species, by using a recently described swine-origin pandemic H1N1 strain, A/Mexico/InDRE4487/2009. In comparison to rhesus macaques, cynomolgus macaques developed significantly higher levels of virus replication in the upper airways and in the lungs, involving both peak level and duration of virus production, as well as higher increases in body temperature. In contrast, clinical symptoms, including respiratory distress, were more easily observed in rhesus macaques. Expression of sialyl-α-2,6-Gal saccharides, the main receptor for human influenza A viruses, was 50 to 73 times more abundant in trachea and bronchus of cynomolgus macaques relative to rhesus macaques. The study also shows that common marmosets, a New World non-human primate species, are susceptible to infection with pandemic H1N1. The study results favor the cynomolgus macaque as model for pandemic H1N1 influenza virus research because of the more uniform and high levels of virus replication, as well as temperature increases, which may be due to a more abundant expression of the main human influenza virus receptor in the trachea and bronchi.

  17. Pandemic influenza A/H1N1 virus infection and TNF, LTA, IL1B, IL6, IL8, and CCL polymorphisms in Mexican population: a case-control study.

    Science.gov (United States)

    Morales-García, Guadalupe; Falfán-Valencia, Ramcés; García-Ramírez, Román Alejandro; Camarena, Ángel; Ramirez-Venegas, Alejandra; Castillejos-López, Manuel; Pérez-Rodríguez, Martha; González-Bonilla, César; Grajales-Muñíz, Concepción; Borja-Aburto, Víctor; Mejía-Aranguré, Juan Manuel

    2012-11-13

    Some patients have a greater response to viral infection than do others having a similar level of viral replication. Hypercytokinemia is the principal immunopathological mechanism that contributes to a severer clinical course in cases of influenza A/H1N1. The benefit produced, or damage caused, by these cytokines in severe disease is not known. The genes that code for these molecules are polymorphic and certain alleles have been associated with susceptibility to various diseases. The objective of the present study was to determine whether there was an association between polymorphisms of TNF, LTA, IL1B, IL6, IL8, and CCL1 and the infection and severity of the illness caused by the pandemic A/H1N1 in Mexico in 2009. Case-control study. The cases were patients confirmed with real time PCR with infection by the A/H1N1 pandemic virus. The controls were patients with infection like to influenza and non-familial healthy contacts of the patients with influenza. Medical history and outcome of the disease was registered. The DNA samples were genotyped for polymorphisms TNF rs361525, rs1800629, and rs1800750; LTA rs909253; IL1B rs16944; IL6 rs1818879; IL8 rs4073; and CCL1 rs2282691. Odds ratio (OR) and the 95% confidence interval (95% CI) were calculated. The logistic regression model was adjusted by age and severity of the illness in cases. Infection with the pandemic A/H1N1 virus was associated with the following genotypes: TNF rs361525 AA, OR = 27.00; 95% CI = 3.07-1248.77); LTA rs909253 AG (OR = 4.33, 95% CI = 1.82-10.32); TNF rs1800750 AA (OR = 4.33, 95% CI = 1.48-12.64); additionally, LTA rs909253 AG showed a limited statistically significant association with mortality (p = 0.06, OR = 3.13). Carriers of the TNF rs1800629 GA genotype were associated with high levels of blood urea nitrogen (p = 0.05); those of the TNF rs1800750 AA genotype, with high levels of creatine phosphokinase (p=0.05). The IL1B rs16944 AA genotype was associated with an elevated number of

  18. Pandemic influenza A/H1N1 virus infection and TNF, LTA, IL1B, IL6, IL8, and CCL polymorphisms in Mexican population: a case–control study

    Science.gov (United States)

    2012-01-01

    Background Some patients have a greater response to viral infection than do others having a similar level of viral replication. Hypercytokinemia is the principal immunopathological mechanism that contributes to a severer clinical course in cases of influenza A/H1N1. The benefit produced, or damage caused, by these cytokines in severe disease is not known. The genes that code for these molecules are polymorphic and certain alleles have been associated with susceptibility to various diseases. The objective of the present study was to determine whether there was an association between polymorphisms of TNF, LTA, IL1B, IL6, IL8, and CCL1 and the infection and severity of the illness caused by the pandemic A/H1N1 in Mexico in 2009. Methods Case–control study. The cases were patients confirmed with real time PCR with infection by the A/H1N1 pandemic virus. The controls were patients with infection like to influenza and non-familial healthy contacts of the patients with influenza. Medical history and outcome of the disease was registered. The DNA samples were genotyped for polymorphisms TNF rs361525, rs1800629, and rs1800750; LTA rs909253; IL1B rs16944; IL6 rs1818879; IL8 rs4073; and CCL1 rs2282691. Odds ratio (OR) and the 95% confidence interval (95% CI) were calculated. The logistic regression model was adjusted by age and severity of the illness in cases. Results Infection with the pandemic A/H1N1 virus was associated with the following genotypes: TNF rs361525 AA, OR = 27.00; 95% CI = 3.07–1248.77); LTA rs909253 AG (OR = 4.33, 95% CI = 1.82–10.32); TNF rs1800750 AA (OR = 4.33, 95% CI = 1.48–12.64); additionally, LTA rs909253 AG showed a limited statistically significant association with mortality (p = 0.06, OR = 3.13). Carriers of the TNF rs1800629 GA genotype were associated with high levels of blood urea nitrogen (p = 0.05); those of the TNF rs1800750 AA genotype, with high levels of creatine phosphokinase (p=0.05). The IL1B rs16944 AA genotype was associated

  19. Pandemic influenza A/H1N1 virus infection and TNF, LTA, IL1B, IL6, IL8, and CCL polymorphisms in Mexican population: a case–control study

    Directory of Open Access Journals (Sweden)

    Morales-García Guadalupe

    2012-11-01

    Full Text Available Abstract Background Some patients have a greater response to viral infection than do others having a similar level of viral replication. Hypercytokinemia is the principal immunopathological mechanism that contributes to a severer clinical course in cases of influenza A/H1N1. The benefit produced, or damage caused, by these cytokines in severe disease is not known. The genes that code for these molecules are polymorphic and certain alleles have been associated with susceptibility to various diseases. The objective of the present study was to determine whether there was an association between polymorphisms of TNF, LTA, IL1B, IL6, IL8, and CCL1 and the infection and severity of the illness caused by the pandemic A/H1N1 in Mexico in 2009. Methods Case–control study. The cases were patients confirmed with real time PCR with infection by the A/H1N1 pandemic virus. The controls were patients with infection like to influenza and non-familial healthy contacts of the patients with influenza. Medical history and outcome of the disease was registered. The DNA samples were genotyped for polymorphisms TNF rs361525, rs1800629, and rs1800750; LTA rs909253; IL1B rs16944; IL6 rs1818879; IL8 rs4073; and CCL1 rs2282691. Odds ratio (OR and the 95% confidence interval (95% CI were calculated. The logistic regression model was adjusted by age and severity of the illness in cases. Results Infection with the pandemic A/H1N1 virus was associated with the following genotypes: TNF rs361525 AA, OR = 27.00; 95% CI = 3.07–1248.77; LTA rs909253 AG (OR = 4.33, 95% CI = 1.82–10.32; TNF rs1800750 AA (OR = 4.33, 95% CI = 1.48–12.64; additionally, LTA rs909253 AG showed a limited statistically significant association with mortality (p = 0.06, OR = 3.13. Carriers of the TNF rs1800629 GA genotype were associated with high levels of blood urea nitrogen (p = 0.05; those of the TNF rs1800750 AA genotype, with high levels of creatine phosphokinase (p=0.05. The IL1B rs16944 AA

  20. Screening of random peptide library of hemagglutinin from pandemic 2009 A(H1N1 influenza virus reveals unexpected antigenically important regions.

    Directory of Open Access Journals (Sweden)

    Wanghui Xu

    Full Text Available The antigenic structure of the membrane protein hemagglutinin (HA from the 2009 A(H1N1 influenza virus was dissected with a high-throughput screening method using complex antisera. The approach involves generating yeast cell libraries displaying a pool of random peptides of controllable lengths on the cell surface, followed by one round of fluorescence-activated cell sorting (FACS against antisera from mouse, goat and human, respectively. The amino acid residue frequency appearing in the antigenic peptides at both the primary sequence and structural level was determined and used to identify "hot spots" or antigenically important regions. Unexpectedly, different antigenic structures were seen for different antisera. Moreover, five antigenic regions were identified, of which all but one are located in the conserved HA stem region that is responsible for membrane fusion. Our findings are corroborated by several recent studies on cross-neutralizing H1 subtype antibodies that recognize the HA stem region. The antigenic peptides identified may provide clues for creating peptide vaccines with better accessibility to memory B cells and better induction of cross-neutralizing antibodies than the whole HA protein. The scheme used in this study enables a direct mapping of the antigenic regions of viral proteins recognized by antisera, and may be useful for dissecting the antigenic structures of other viral proteins.

  1. Memory immune responses against pandemic (H1N1 2009 influenza virus induced by a whole particle vaccine in cynomolgus monkeys carrying Mafa-A1*052:02.

    Directory of Open Access Journals (Sweden)

    Masahiko Arikata

    Full Text Available We made an H1N1 vaccine candidate from a virus library consisting of 144 ( = 16 HA×9 NA non-pathogenic influenza A viruses and examined its protective effects against a pandemic (2009 H1N1 strain using immunologically naïve cynomolgus macaques to exclude preexisting immunity and to employ a preclinical study since preexisting immunity in humans previously vaccinated or infected with influenza virus might make comparison of vaccine efficacy difficult. Furthermore, macaques carrying a major histocompatibility complex class I molecule, Mafa-A1*052:02, were used to analyze peptide-specific CD8(+ T cell responses. Sera of macaques immunized with an inactivated whole particle formulation without addition of an adjuvant showed higher neutralization titers against the vaccine strain A/Hokkaido/2/1981 (H1N1 than did sera of macaques immunized with a split formulation. Neutralization activities against the pandemic strain A/Narita/1/2009 (H1N1 in sera of macaques immunized twice with the split vaccine reached levels similar to those in sera of macaques immunized once with the whole particle vaccine. After inoculation with the pandemic virus, the virus was detected in nasal samples of unvaccinated macaques for 6 days after infection and for 2.67 days and 5.33 days on average in macaques vaccinated with the whole particle vaccine and the split vaccine, respectively. After the challenge infection, recall neutralizing antibody responses against the pandemic virus and CD8(+ T cell responses specific for nucleoprotein peptide NP262-270 bound to Mafa-A1*052:02 in macaques vaccinated with the whole particle vaccine were observed more promptly or more vigorously than those in macaques vaccinated with the split vaccine. These findings demonstrated that the vaccine derived from our virus library was effective for pandemic virus infection in macaques and that the whole particle vaccine conferred more effective memory and broader cross-reactive immune responses

  2. A clinical trial to assess the immunogenicity and safety of Inactivated Influenza Vaccine (Whole Virion IP (Pandemic Influenza (H1N1 2009 Monovalent Vaccine; VaxiFlu-S ™ in healthy Indian adult population

    Directory of Open Access Journals (Sweden)

    A H Kubavat

    2011-01-01

    Full Text Available Background : The pandemic of H1N1 2009 influenza has spread world over and low degree of virus transmission has continued in several regions of India. Aims : To assess the immunogenicity and safety of Pandemic Influenza (H1N1 2009 Monovalent Vaccine in healthy adult Indian population. Settings and Design : Prospective, open label, multicentric, phase 2/3 clinical trial. Materials and Methods : Healthy adult Indian subjects belonging to either 18-59 years or ≥60 years age groups were enrolled and administered a single 0.5 ml (≥15 mcg of hemagglutinin antigen dose of vaccine in the deltoid muscle. Anti-hemagglutinin antibody titer was assessed at baseline and 21 (±2 days after vaccination by Hemagglutination Inhibition (HI test. Safety assessments were done for a period of 42 days. Statistical Analysis Used : Percentages of appropriate population with 95% confidence intervals calculated, log transformation of the data to calculate Geometric Mean Titers (GMTs and chi-square test and student′s t-test applied for significance testing. Results : 182/198 and 53/63 volunteers in age groups of 18-59 years and ≥60 years, respectively, achieved an HI titer ≥1 : 40 at Day 21 (91.9% [95% confidence interval: 88.1-95.7%] and 84.1% [75.1-93.2%]; P=0.072. Further, 171/198 and 50/63 volunteers in the respective age groups achieved seroconversion/four-fold increase in titer at Day 21 (86.4% [81.6-91.1%] and 79.4% [69.4-89.4%]; P=0.179. A significant rise of 22.6-fold [18.0-28.4] and 10.5-fold [7.4-15.0] was noted in GMT in the respective age groups (P<0.001 for both groups as compared to baseline. Nine vaccine-related adverse events were reported (3.4% incidence [1.2-5.6%], which were of low severity only. Conclusions : Pandemic Influenza (H1N1 2009 Monovalent Vaccine produces excellent immunogenic response with a good tolerability profile in adult Indian population.

  3. Influenza A (H1N1) pneumonia: HRCT findings

    Energy Technology Data Exchange (ETDEWEB)

    Amorim, Viviane Brandao; Rodrigues, Rosana Souza; Barreto, Miriam Menna; Marchiori, Edson, E-mail: edmarchiori@gmail.com [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Zanetti, Glaucia [Escola de Medicina de Petropolis, RJ (Brazil); Hochhegger, Bruno [Santa Casa de Misericordia de Porto Alegre, RS (Brazil)

    2013-11-01

    Objective: to describe aspects found on HRCT scans of the chest in patients infected with the influenza A (H1N1) virus. Methods: we retrospectively analyzed the HRCT scans of 71 patients (38 females and 33 males) with H1N1 infection, confirmed through laboratory tests, between July and September of 2009. The HRCT scans were interpreted by two thoracic radiologists independently, and in case of disagreement, the decisions were made by consensus. Results: the most common HRCT findings were ground-glass opacities (85%), consolidation (64%), or a combination of ground-glass opacities and consolidation (58%). Other findings were airspace nodules (25%), bronchial wall thickening (25%), interlobular septal thickening (21%), crazy-paving pattern (15%), perilobular pattern (3%), and air trapping (3%). The findings were frequently bilateral (89%), with a random distribution (68%). Pleural effusion, when observed, was typically minimal. No lymphadenopathy was identified. Conclusions: the most common findings were ground-glass opacities and consolidations, or a combination of both. Involvement was commonly bilateral with no axial or cranio caudal predominance in the distribution. Although the major tomographic findings in H1N1 infection are nonspecific, it is important to recognize such findings in order to include infection with the H1N1 virus in the differential diagnosis of respiratory symptoms. (author)

  4. Protection against H5N1 Highly Pathogenic Avian and Pandemic (H1N1) 2009 Influenza Virus Infection in Cynomolgus Monkeys by an Inactivated H5N1 Whole Particle Vaccine

    Science.gov (United States)

    Nakayama, Misako; Shichinohe, Shintaro; Itoh, Yasushi; Ishigaki, Hirohito; Kitano, Mitsutaka; Arikata, Masahiko; Pham, Van Loi; Ishida, Hideaki; Kitagawa, Naoko; Okamatsu, Masatoshi; Sakoda, Yoshihiro; Ichikawa, Takaya; Tsuchiya, Hideaki; Nakamura, Shinichiro; Le, Quynh Mai; Ito, Mutsumi; Kawaoka, Yoshihiro; Kida, Hiroshi; Ogasawara, Kazumasa

    2013-01-01

    H5N1 highly pathogenic avian influenza virus (HPAIV) infection has been reported in poultry and humans with expanding clade designations. Therefore, a vaccine that induces immunity against a broad spectrum of H5N1 viruses is preferable for pandemic preparedness. We established a second H5N1 vaccine candidate, A/duck/Hokkaido/Vac-3/2007 (Vac-3), in our virus library and examined the efficacy of inactivated whole particles of this strain against two clades of H5N1 HPAIV strains that caused severe morbidity in cynomolgus macaques. Virus propagation in vaccinated macaques infected with either of the H5N1 HPAIV strains was prevented compared with that in unvaccinated macaques. This vaccine also prevented propagation of a pandemic (H1N1) 2009 virus in macaques. In the vaccinated macaques, neutralization activity, which was mainly shown by anti-hemagglutinin antibody, against H5N1 HPAIVs in plasma was detected, but that against H1N1 virus was not detected. However, neuraminidase inhibition activity in plasma and T-lymphocyte responses in lymph nodes against H1N1 virus were detected. Therefore, cross-clade and heterosubtypic protective immunity in macaques consisted of humoral and cellular immunity induced by vaccination with Vac-3. PMID:24376571

  5. Protection against H5N1 highly pathogenic avian and pandemic (H1N1 2009 influenza virus infection in cynomolgus monkeys by an inactivated H5N1 whole particle vaccine.

    Directory of Open Access Journals (Sweden)

    Misako Nakayama

    Full Text Available H5N1 highly pathogenic avian influenza virus (HPAIV infection has been reported in poultry and humans with expanding clade designations. Therefore, a vaccine that induces immunity against a broad spectrum of H5N1 viruses is preferable for pandemic preparedness. We established a second H5N1 vaccine candidate, A/duck/Hokkaido/Vac-3/2007 (Vac-3, in our virus library and examined the efficacy of inactivated whole particles of this strain against two clades of H5N1 HPAIV strains that caused severe morbidity in cynomolgus macaques. Virus propagation in vaccinated macaques infected with either of the H5N1 HPAIV strains was prevented compared with that in unvaccinated macaques. This vaccine also prevented propagation of a pandemic (H1N1 2009 virus in macaques. In the vaccinated macaques, neutralization activity, which was mainly shown by anti-hemagglutinin antibody, against H5N1 HPAIVs in plasma was detected, but that against H1N1 virus was not detected. However, neuraminidase inhibition activity in plasma and T-lymphocyte responses in lymph nodes against H1N1 virus were detected. Therefore, cross-clade and heterosubtypic protective immunity in macaques consisted of humoral and cellular immunity induced by vaccination with Vac-3.

  6. Susceptibility of turkeys to pandemic-H1N1 virus by reproductive tract insemination

    Directory of Open Access Journals (Sweden)

    Suarez David L

    2010-02-01

    Full Text Available Abstract The current pandemic influenza A H1N1 2009 (pH1N1 was first recognized in humans with acute respiratory diseases in April 2009 in Mexico, in swine in Canada in June, 2009 with respiratory disease, and in turkeys in Chile in June 2009 with a severe drop in egg production. Several experimental studies attempted to reproduce the disease in turkeys, but failed to produce respiratory infection in turkeys using standard inoculation routes. We demonstrated that pH1N1 virus can infect the reproductive tract of turkey hens after experimental intrauterine inoculation, causing decreased egg production. This route of exposure is realistic in modern turkey production because turkey hens are handled once a week for intrauterine insemination in order to produce fertile eggs. This understanding of virus exposure provides an improved understanding of the pathogenesis of the disease and can improve poultry husbandry to prevent disease outbreaks.

  7. [Characteristics of cases hospitalized for severe pandemic (H1N1) 2009 in Catalonia].

    Science.gov (United States)

    Godoy, Pere; Rodés, Anna; Alvarez, Josep; Camps, Neus; Barrabeig, Irene; Sala, María Rosa; Minguell, Sofía; Lafuente, Sarah; Pumarola, Tomás; Domínguez, Angela; Plasència, Antoni

    2011-01-01

    Influenza pandemics may cause more severe cases. The objective was to determine the characteristics of hospitalized severe cases of pandemic influenza in Catalonia and to study risk factors for admission to intensive care unit (ICU). A prospective epidemiologic study of new cases of pandemic influenza hospitalized by their severity between June 2009 and May 2010. Hospitals were asked to declare laboratory confirmed pandemic influenza cases that met the case specific case definition for severe case. A standardized epidemiological survey was conducted to collect information on demographics, clinical characteristics, risk factors, treatment and outcome. Differences between the cases in ICU compared to other severe cases were studied with the odds ratio (OR), which were adjusted using a logistic regression model. We detected total of 773 pandemic influenza (H1N1) 2009 severe cases; 465 (60.2%) of them had at least one risk factor and the most prevalent were: pregnancy 19 (13%), asthma 87 (12%), chronic obstructive pulmonary disease 87 (11.4%) and heart disease 80 (10.5%). Required admission to ICU 293 patients (37.9%). Factors associated with ICU admission were obesity BMI>40 (adjusted OR = 2.5, 95% CI 1.4-4.5) and chronic liver disease (adjusted OR = 2.3, 95% CI 1.1-4.8). This study confirms the high prevalence of pregnancy, chronic respiratory diseases, diabetes and obesity among pandemic influenza severe cases. Obesity acts as a risk factor for ICU admission and should therefore be considered as an indicator for influenza vaccination.

  8. Evolutionary trends of A(H1N1 influenza virus hemagglutinin since 1918.

    Directory of Open Access Journals (Sweden)

    Jun Shen

    2009-11-01

    Full Text Available The Pandemic (H1N1 2009 is spreading to numerous countries and causing many human deaths. Although the symptoms in humans are mild at present, fears are that further mutations in the virus could lead to a potentially more dangerous outbreak in subsequent months. As the primary immunity-eliciting antigen, hemagglutinin (HA is the major agent for host-driven antigenic drift in A(H3N2 virus. However, whether and how the evolution of HA is influenced by existing immunity is poorly understood for A(H1N1. Here, by analyzing hundreds of A(H1N1 HA sequences since 1918, we show the first evidence that host selections are indeed present in A(H1N1 HAs. Among a subgroup of human A(H1N1 HAs between 1918 approximately 2008, we found strong diversifying (positive selection at HA(1 156 and 190. We also analyzed the evolutionary trends at HA(1 190 and 225 that are critical determinants for receptor-binding specificity of A(H1N1 HA. Different A(H1N1 viruses appeared to favor one of these two sites in host-driven antigenic drift: epidemic A(H1N1 HAs favor HA(1 190 while the 1918 pandemic and swine HAs favor HA(1 225. Thus, our results highlight the urgency to understand the interplay between antigenic drift and receptor binding in HA evolution, and provide molecular signatures for monitoring future antigenically drifted 2009 pandemic and seasonal A(H1N1 influenza viruses.

  9. International collaboration to assess the risk of Guillain Barré Syndrome following Influenza A (H1N1) 2009 monovalent vaccines

    NARCIS (Netherlands)

    C. Dodd (Caitlin); S.A. Romio (Silvana); S. Black (Steve); C. Vellozzi (Claudia); N.J. Andrews (Nick); M.C.J.M. Sturkenboom (Miriam); P. Zuber (Patrick); W. Hua (Wei); J. Bonhoeffer (Jan); J. Buttery (Jim); N. Crawford (Nigel); G. Deceuninck (Genevieve); C.S. de Vries (Corinne); P. de Wals (Philippe); D. Gimeno (David); H. Heijbel (Harald); H. Hughes (Hayley); K. Hur (Kwan); A. Hviid (Anders); J. Kelman (Jeffrey); T. Kilpi (Tehri); S.K. Chuang (S.); T. Macartney (Thomas); M. Rett (Melisa); V.R. Lopez-Callada (Vesta Richardson); D. Salmon (Daniel); F.G. Sanchez (Francisco Gimenez); N. Sanz (Nuria); B. Silverman (Bernard); J. Storsaeter (Jann); U. Thirugnanam (Umapathi); N.A.T. van der Maas (Nicoline); K. Yih (Katherine); T. Zhang (Teng Fei); H.S. Izurieta (Hector); B.J. Addis; A. Akhtar (Aysha); J. Cope (Judith); R.L. Davis (Robert); P. Gargiullo (Paul); X. Kurz (Xavier); B. Law (Barbara); I. Sahinovic (Isabelle); J. Tokars (Jerry); P. Serrano (Pedro); A. Cheng (Aixin); N.J. Andrews (Nick); P. Charles (Pat); H. Clothier (Hazel); B. Day (Bruce); T. Day (Timothy); P. Gates (Peter); R. MacDonnell (Richard); L. Roberts (Les); V. Rodriguez-Casero (Vic-toria); T. Wijeratne (Tissa); H.A.L. Kiers (Henk); C. Blyth (Christopher); R. Booy (Robert); E. Elliott (Elizabeth); M.R. Gold (Michael); H. Marshall; P. McIntyre (Peter); P. Richmond (Peter); J. Royle (Jenny); N.W. Wood (Nicholas); Y. Zurynski (Yvonne); G. Calvo (Gonzalo); M. Campins (Magda); N. Corominas (Nuria); F. Torres (Ferran); V. Valls; A. Vilella (Ángels); A. Dutra (Amalia); A. Eick-Cost (Angelia); H.M. Jackson (Henry); K. Garman (Katherine); Z. Hu (Zheng); J. Rigo; J. Badoo (Judith); D Cho (David); L.L. Polakowski (Laura); S.K. Sandhu (Sukhminder); G. Sun (Guoying); H.-S.S. Chan (Hoi-Shan Sophelia); K.-Y. Chan (Kwok-Yin); R. Cheung (Raymond); Y-F. Cheung (Yuk-Fai); S. Cherk (Sharon); S.K Chuang (S.); D. Fok (Dennis); B.-H. Fung (Bun-Hey); K.-F. Ko (Kwai-Fu); K.W. Lau (Ka Wing); K.-K. Lau (Kwok-Kwong); P. Li (Pulin); H.-T. Liu (Hui-Tung); S.-H. Liu (Shao-Haei); K. Mok (Kin); J. So (Joanna); W. Wong (Winnie); S.-P. Wu (Shun-Ping); V. Avagyan (Vardan); R. Ball (Robert); D. Burwen (Dale); R.L. Franks (Riley); J.M. Gibbs (Jonathan); R.E. Kliman (Rebecca); S. Kropp (Silke); T.E. MaCurdy (Thomas); D.B. Martin (David); S.-D.K. Sandhu (Sukhmin-Der); B.B. Worrall (Bradford B.); D.E.F. Fuentes (Dra. Elvira Fuentes); P.C.O. González (Paola Carolina Ojeda); V.F. Reyna (Valerie ); M. Kulldorff (Martin); G. Lee (Grace); T.A. Lieu (Tracy); S. Platt; G.D. Serres (Gaston De); K. Jabin (Kamilah); B.L.S. Soh (Bee Leng Sally); L. Arnheim-Dahlström (Lisen); A. Castot (Anne); H.E. de Melker (Hester); J.P. Dieleman (Jeanne); J. Hallgren (Jonal); B.C. Jacobs (Bart); K. Johansen (Kari); P Kramarz (Piotr); M. Lapeyre (Maryse); T. Leino (Tuija); D. Mølgaard-Nielsen (Ditte); M. Mosseveld (Mees); H.K. Olberg (Henning K); C.-M. Sammon (Cor-Mac); C. Saussier (Christel); M.J. Schuemie (Martijn); A. Sommet (Agnès); P. Sparen (Pär); H. Svanström (Henrik); A.M. Vanrolleghem (Ann M.); D.M. Weibel (Daniel); J.D. Domingo (Javier Diez); J.L. Esparza (José LuísMicó); R.M.O. Lucas (Rafael M. Ortí); J.B.M. Maseres (Juan B. Mollar); J.L.A. Sánchez (José Luís Alfonso); M.G. Sánchez (Mercedes Garcés); V.Z. Viguer (Vicente Zanón); F. Cunningham (Francesca); B. Thakkar (Bharat); R. Zhang (Rongping)

    2013-01-01

    textabstractBackground: The global spread of the 2009 novel pandemic influenza A (H1N1) virus led to the accelerated production and distribution of monovalent 2009 Influenza A (H1N1) vaccines (pH1N1). This pandemic provided the opportunity to evaluate the risk of Guillain-Barré syndrome (GBS), which

  10. The Neurological Manifestations of H1N1 Influenza Infection; Diagnostic Challenges and Recommendations

    Directory of Open Access Journals (Sweden)

    Ali Akbar Asadi-Pooya

    2011-03-01

    Full Text Available Background: World Health Organization declared pandemic phase of human infection with novel influenza A (H1N1 in April 2009. There are very few reports about the neurological complications of H1N1 virus infection in the literature. Occasionally, these complications are severe and even fatal in some individuals. The aims of this study were to report neurological complaints and/or complications associated with H1N1 virus infection. Methods: The medical files of all patients with H1N1 influenza infection admitted to a specified hospital in the city of Shiraz, Iran from October through November 2009 were reviewed. More information about the patients were obtained by phone calls to the patients or their care givers. All patients had confirmed H1N1 virus infection with real-time PCR assay. Results: Fifty-five patients with H1N1 infection were studied. Twenty-three patients had neurological signs and/or symptoms. Mild neurological complaints may be reported in up to 42% of patients infected by H1N1 virus. Severe neurological complications occurred in 9% of the patients. The most common neurological manifestations were headache, numbness and paresthesia, drowsiness and coma. One patient had a Guillain-Barre syndrome-like illness, and died in a few days. Another patient had focal status epilepticus and encephalopathy. Conclusions: The H1N1 infection seems to have been quite mild with a self-limited course in much of the world, yet there appears to be a subset, which is severely affected. We recommend performing diagnostic tests for H1N1influenza virus in all patients with respiratory illness and neurological signs/symptoms. We also recommend initiating treatment with appropriate antiviral drugs as soon as possible in those with any significant neurological presentation accompanied with respiratory illness and flu-like symptoms

  11. Enhanced pneumonia and disease in pigs vaccinated with an inactivated human-like (δ-cluster) H1N2 vaccine and challenged with pandemic 2009 H1N1 influenza virus.

    Science.gov (United States)

    Gauger, Phillip C; Vincent, Amy L; Loving, Crystal L; Lager, Kelly M; Janke, Bruce H; Kehrli, Marcus E; Roth, James A

    2011-03-24

    Influenza is an economically important respiratory disease affecting swine world-wide with potential zoonotic implications. Genetic reassortment and drift has resulted in genetically and antigenically distinct swine influenza viruses (SIVs). Consequently, prevention of SIV infection is challenging due to the increased rate of genetic change and a potential lack of cross-protection between vaccine strains and circulating novel isolates. This report describes a vaccine-heterologous challenge model in which pigs were administered an inactivated H1N2 vaccine with a human-like (δ-cluster) H1 six and three weeks before challenge with H1 homosubtypic, heterologous 2009 pandemic H1N1. At necropsy, macroscopic and microscopic pneumonia scores were significantly higher in the vaccinated and challenged (Vx/Ch) group compared to non-vaccinated and challenged (NVx/Ch) pigs. The Vx/Ch group also demonstrated enhanced clinical disease and a significantly elevated pro-inflammatory cytokine profile in bronchoalveolar lavage fluid compared to the NVx/Ch group. In contrast, viral shedding and replication were significantly higher in NVx/Ch pigs although all challenged pigs, including Vx/Ch pigs, were shedding virus in nasal secretions. Hemagglutination inhibition (HI) and serum neutralizing (SN) antibodies were detected to the priming antigen in the Vx/Ch pigs but no measurable cross-reacting HI or SN antibodies were detected to pandemic H1N1 (pH1N1). Overall, these results suggest that inactivated SIV vaccines may potentiate clinical signs, inflammation and pneumonia following challenge with divergent homosubtypic viruses that do not share cross-reacting HI or SN antibodies. Published by Elsevier Ltd.

  12. [Predicting spread of new pandemic swine-origin influenza A (H1N1) in local mid-size city: evaluation of hospital bed shortage and effectiveness of vaccination].

    Science.gov (United States)

    Takeuchi, Shouhei; Kuroda, Yoshiki

    2010-01-01

    On April 24th, 2009, a new swine-origin influenza A (H1N1) was first reported in Mexico. Japan confirmed cases of the flu on May 9th, and the pandemic in Japan has become full-scale. The Ministry of Health, Labor and Welfare of Japan announced that the first peak of this pandemic was predicted to occur in October, 2009. Therefore, it is most important to predict the progress of this pandemic to be able to use medical resources effectively in Japan. We used a modified susceptible-exposed-infected-recovered (SEIR) model to calculate the number of infected people and hospital bed shortage during this pandemic. In this model, available medical resources were investigated on the basis of four vaccination scenarios. Our model showed that it would take a further six months for the pandemic to peak than was predicted by the Ministry of Health, Labor and Welfare of Japan. Without vaccination, at the peak of the pandemic 23,689 out of 400,000 people would be infected and the hospital bed shortage would reach 7,349 in total. We suggest that mathematical models are strong tools to predict the spread of infectious diseases. According to our model, it is possible to prevent hospital bed shortage by vaccination.

  13. Signal Immune Reactions of Macrophages Differentiated from THP-1 Monocytes to Infection with Pandemic H1N1PDM09 Virus and H5N2 and H9N2 Avian Influenza A Virus.

    Science.gov (United States)

    Sokolova, T M; Poloskov, V V; Shuvalov, A N; Rudneva, I A; Timofeeva, T A

    2018-03-01

    In culture of THP-1 cells differentiated into macrophages with PMA (THP-PMA macrophages) infected with influenza viruses of subtypes H1, H5 and H9, we measured the expression of TLR7 and RIG1 receptor genes, sensors of viral RNA and ribonucleoprotein, and the levels of production of inflammatory cytokines IL-1β, TNFα, IL-10, and IFNα. The sensitivity and inflammatory response of THP-PMA macrophages to pandemic influenza A virus H1N1pdm09 and avian influenza H5N2 and H9N2 viruses correlate with the intracellular level of their viral RNA and activation of the RIG1 gene. Abortive infection is accompanied by intensive macrophage secretion of TNFα, IL-1β, and toxic factors inducing cell death. Activity of endosomal TLR7 receptor gene changed insignificantly in 24 h after infection and significantly decreased in 48 and 72 h under the action of H5N2 and H9N2, which correlated with manifestation of the cytopathogenic effect of these viruses. H5N2 and H9N2 avian viruses in THP-PMA macrophages are strong activators of the expression of the gene of the cytoplasmic RIG1 receptor 24 and 48 h after infection, and the pandemic virus H1N1pdm09 is a weak stimulator of RIG1 gene. Avian influenza H5N2 and H9N2 viruses are released by rapid induction of the inflammatory response in macrophages. At the late stages of infection, we observed a minor increase in IL-10 secretion in macrophages and, probably, the polarization of a part of the population in type M2. The studied influenza A viruses are weak inductors of IFN in THP-PMA macrophages. In the culture medium of THP-PMA macrophages infected with H9N2 and H5N2 viruses, MTT test revealed high levels of toxic factors causing the death of Caco-2 cells. In contrast to avian viruses, pandemic virus H1N1pdm09 did not induce production of toxic factors.

  14. Replication, Pathogenesis and Transmission of Pandemic (H1N1) 2009 Virus in Non-Immune Pigs

    DEFF Research Database (Denmark)

    Brookes, Sharon M; Nunez, Alejandor; Choudhury, Bhudipa

    2010-01-01

    The declaration of the human influenza A pandemic (H1N1) 2009 (H1N1/09) raised important questions, including origin and host range [1,2]. Two of the three pandemics in the last century resulted in the spread of virus to pigs (H1N1, 1918; H3N2, 1968) with subsequent independent establishment...... and evolution within swine worldwide [3]. A key public and veterinary health consideration in the context of the evolving pandemic is whether the H1N1/09 virus could become established in pig populations [4]. We performed an infection and transmission study in pigs with A/California/07/09. In combination......, with clearly demonstrable pulmonary pathology, there was apparent selection of a virus variant with glycine (225G). These findings provide potential clues to the existence and biological significance of viral receptor-binding variants with 225D and 225G during the 1918 pandemic [5]....

  15. Pandemic H1N1 2009 ('swine flu'): diagnostic and other challenges.

    Science.gov (United States)

    Burkardt, Hans-Joachim

    2011-01-01

    Pandemic H1N1 2009 ('swine flu') virus was 'the virus of the year 2009' because it affected the lives of many people in this year. H1N1 was first described in California in April 2009 and spread very rapidly all over the globe. The fast global penetration of the swine flu caused the WHO in Geneva to call the infection with H1N1 a new pandemic with a rapid escalation of the different pandemic phases that ended on 11 June 2009, with the declaration of phase 6 (full-blown pandemic). This had far-reaching consequences for the local health authorities in the different affected countries and created awareness in the public and fear in the experts and even more so in many lay people. The consequences were: setting up reliable diagnostic tests as soon as possible; enhanced production, distribution and stock creation of the few drugs that were available to treat newly infected persons; and development, production, distribution and stock creation of new and appropriate anti-H1N1 swine flu vaccines. This all resulted in enormous costs in the local healthcare systems and also required smart and diligent logistics, because demand for all this was, in most cases, much higher than availability. Fortunately, the pandemic ended quite quickly (there was no 'second wave' as had been anticipated by some experts) and the death toll was moderate, compared with other influenza pandemic in the past and even to the regular annual appearance of the seasonal flu. This favorable outcome, however, provoked some harsh criticism that the WHO and healthcare systems in general had over-reacted and by doing so, a lot of money was thrown out of the window. This article describes the history of the H1N1 pandemic, the diagnostic challenges and resolutions, touches on treatment and vaccination very briefly and also comments on the criticism and arguments that came up immediately at the end and following the termination of the pandemic situation.

  16. Illinois department of public health H1N1/A pandemic communications evaluation survey.

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, D.; Decision and Information Sciences

    2010-09-16

    Because of heightened media coverage, a 24-hour news cycle and the potential miscommunication of health messages across all levels of government during the onset of the H1N1 influenza outbreak in spring 2009, the Illinois Department of Public Health (IDPH) decided to evaluate its H1N1 influenza A communications system. IDPH wanted to confirm its disease information and instructions were helping stakeholders prepare for and respond to a novel influenza outbreak. In addition, the time commitment involved in preparing, issuing, monitoring, updating, and responding to H1N1 federal guidelines/updates and media stories became a heavy burden for IDPH staff. The process and results of the H1N1 messaging survey represent a best practice that other health departments and emergency management agencies can replicate to improve coordination efforts with stakeholder groups during both emergency preparedness and response phases. Importantly, the H1N1 survey confirmed IDPH's messages were influencing stakeholders decisions to activate their pandemic plans and initiate response operations. While there was some dissatisfaction with IDPH's delivery of information and communication tools, such as the fax system, this report should demonstrate to IDPH that its core partners believe it has the ability and expertise to issue timely and accurate instructions that can help them respond to a large-scale disease outbreak in Illinois. The conclusion will focus on three main areas: (1) the survey development process, (2) survey results: best practices and areas for improvement and (3) recommendations: next steps.

  17. Clinical profile and outcome of critically ill pregnant females with H1N1 influenza

    Directory of Open Access Journals (Sweden)

    Minal Shastri

    2016-12-01

    Full Text Available Background Record based review of the 2009 H1N1 Influenza pandemic suggests that pregnant women are at higher risk for hospitalization and death due to H1N1 Influenza. Aims To study the clinical profile and outcome of critically ill pregnant females admitted in intensive care unit (ICU with real-time recombinant polymerase chain reaction (rRT-PCR proven positive H1N1 cases. Methods A retrospective record-review based study was conducted at Sir SayajiRao General Hospital (SSGH and Medical College, Vadodara on data of confirmed rRT-PCR H1N1 pregnant females admitted during the pandemics of 2010and 2015. Demographics, clinical profile and laboratory investigations were recorded and outcomes (survived or expired were analysed. Results There were a total of 20 H1N1 positive pregnant females requiring ICU admission. With equal demographic distribution among rural and urban population, cough and fever were the most common presenting complaints. 65 per cent were in third trimester, the subgroup which also had the highest mortality. Mean days from onset until presentation was 5.05 days. 12 (60 per cent patients’ required invasive mode of ventilation and all died. Average hospital stay was 7 days. Foetus had favourable outcome in patients who recovered from H1N1 acute illness. Conclusion Pregnant females in our study had 60 per cent mortality. Thus, awareness, early diagnosis and treatment should be provided to them. Guidelines, policy changes and government protocols are required specifically for pregnant females with H1N1 Influenza A infection. Our study was an observational study and comparisons with non-pregnant females were not done, conclusions applicable to entire pregnant population was not derived.

  18. Pandemic (H1N1) 2009 virus infection during pregnancy in South India.

    Science.gov (United States)

    Pramanick, Angsumita; Rathore, Swati; Peter, John V; Moorthy, Mahesh; Lionel, Jessie

    2011-04-01

    To assess the clinical profile of pregnant/puerperal women from a semi-urban Indian population who were infected with pandemic (H1N1) 2009 virus (P[H1N1]2009v) and to evaluate their outcome. In a cross-sectional study, 566 women (79 pregnant/puerperal, 487 nonpregnant) who presented to a tertiary care hospital with influenza-like illness were tested for P(H1N1)2009v by real-time reverse transcriptase polymerase chain reaction. Outcomes measures were the maternal mortality and the perinatal mortality rate (PMR). Twenty (25%) pregnant/puerperal and 144 (30%) nonpregnant women tested positive for P(H1N1)2009v, with 5 pregnant and 3 postpartum women requiring admission to the intensive care unit (ICU). P(H1N1)2009v-related mortality was higher in pregnant than nonpregnant women (25% versus 8%; P=0.04). In the pregnant/puerperal cohort, factors associated with death included delayed presentation (median 6days versus 1.5days in survivors; P=0.007), need for ICU admission (P=0.004), need for ventilation (P=0.001), and renal failure (P=0.001). The PMR was 55.5/1000 births compared with 33.5/1000 births in the hospital overall during the study period. In a low-income country, P(H1N1)2009v infection in pregnancy is associated with considerable mortality. Delayed presentation to a tertiary care center, lack of awareness, and restricted access to treatment might have contributed to the high mortality. Copyright © 2011 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  19. Economic Evaluation of Individual School Closure Strategies: The Hong Kong 2009 H1N1 Pandemic.

    Directory of Open Access Journals (Sweden)

    Zoie Shui-Yee Wong

    Full Text Available School closures as a means of containing the spread of disease have received considerable attention from the public health community. Although they have been implemented during previous pandemics, the epidemiological and economic effects of the closure of individual schools remain unclear.This study used data from the 2009 H1N1 pandemic in Hong Kong to develop a simulation model of an influenza pandemic with a localised population structure to provide scientific justifications for and economic evaluations of individual-level school closure strategies.The estimated cost of the study's baseline scenario was USD330 million. We found that the individual school closure strategies that involved all types of schools and those that used a lower threshold to trigger school closures had the best performance. The best scenario resulted in an 80% decrease in the number of cases (i.e., prevention of about 830,000 cases, and the cost per case prevented by this intervention was USD1,145; thus, the total cost was USD1.28 billion.This study predicts the effects of individual school closure strategies on the 2009 H1N1 pandemic in Hong Kong. Further research could determine optimal strategies that combine various system-wide and district-wide school closures with individual school triggers across types of schools. The effects of different closure triggers at different phases of a pandemic should also be examined.

  20. Development of a diagnostic kit for Tamiflu-resistant influenza A (H1N1)

    International Nuclear Information System (INIS)

    Jung, I. L.; Hong, S. W.

    2012-01-01

    Swine influenza A, which has been pandemic worldwide since 2009, is a new type virus derived from A type influenza. Although some drugs against the contageous disease, such as relenza and tamiflu, have been commercialized, those drug resistant viruses could be also followed by the wide usage of drugs. For examples, Tamiflu-resistant viruses, the mutant type viruses, can not be cured by the treatment of tamiflu anymore. Thus, a quick diagnosis for the wild type (tamiflu-sensitive) and mutant (tamiflu-resistant) virus would be essential in order to prevent the wide spread of viruses. In spite of that, unfortunately, very few studies have been conducted until now. If we could tell the differences between tamiflu-resistant and -sensitive patients using by the proper diagnostic kit, not only patient specific treatment would be possible, but also the spread of viruses would be effectively prevented. Currently used detection methods for the swine influenza A H1N1, which were originated from CDC, USA, can not detect the tamiflu-resistant swine influenza A H1N1, but only can detect tamiflu-sensitive wine influenza A H1N1. In this study, all the primers for the detection of swInfA, swH1, MP and NA (neuraminidase) have been developed in order to detect both tamiflu-resistant and tamiflu-sensitive swine influenza A H1N1s simultaneously, and then, new multiplex RT-PCR methods has been established

  1. Development of a diagnostic kit for Tamiflu-resistant influenza A (H1N1)

    Energy Technology Data Exchange (ETDEWEB)

    Jung, I. L.; Hong, S. W.

    2012-01-15

    Swine influenza A, which has been pandemic worldwide since 2009, is a new type virus derived from A type influenza. Although some drugs against the contageous disease, such as relenza and tamiflu, have been commercialized, those drug resistant viruses could be also followed by the wide usage of drugs. For examples, Tamiflu-resistant viruses, the mutant type viruses, can not be cured by the treatment of tamiflu anymore. Thus, a quick diagnosis for the wild type (tamiflu-sensitive) and mutant (tamiflu-resistant) virus would be essential in order to prevent the wide spread of viruses. In spite of that, unfortunately, very few studies have been conducted until now. If we could tell the differences between tamiflu-resistant and -sensitive patients using by the proper diagnostic kit, not only patient specific treatment would be possible, but also the spread of viruses would be effectively prevented. Currently used detection methods for the swine influenza A H1N1, which were originated from CDC, USA, can not detect the tamiflu-resistant swine influenza A H1N1, but only can detect tamiflu-sensitive wine influenza A H1N1. In this study, all the primers for the detection of swInfA, swH1, MP and NA (neuraminidase) have been developed in order to detect both tamiflu-resistant and tamiflu-sensitive swine influenza A H1N1s simultaneously, and then, new multiplex RT-PCR methods has been established.

  2. [Risk communication during health crises: results of a cross-sectional study to evaluate the effectiveness of adopted corporate communication strategies during the H1N1 influenza pandemic in Italy and on the training needs of health professionals].

    Science.gov (United States)

    De Giusti, Maria; Mannocci, Alice; Miccoli, Silvia; Palazzo, Caterina; Di Thiene, Domitilla; Scalmato, Valeria; Ursillo, Paolo; Monteduro, Maria Antonietta; Turri, Alberto; Mazzoli, Pier Giovanni; Boccia, Antonio; La Torre, Giuseppe

    2012-01-01

    The objectives of this study were to evaluate the effectiveness of corporate communication activities carried out during the A(H1N1) pandemic influenza in Italy and to identify educational needs of health professionals with regards to crisis communication. The study compared two samples representing respectively the general population and health professionals, living in different regions of northern, central and southern Italy. A self-administered questionnaire was used, with questions on knowledge about preventive measures during a pandemic and on satisfaction with the adopted communication campaigns. Study results highlight that both samples had very little knowledge of appropriate preventive behaviors to be adopted during a pandemic. The sample of health professionals received a greater amount of information about the pandemic with respect to the general population and showed a strong interest toward the problem of receiving adequate training in risk communication. The degree of knowledge about preventive measures is directly proportional to the existence of institutional communication activities and to having consulted a health professional.

  3. Age as Risk Factor for Death from Pandemic (H1N1) 2009, Chile

    Science.gov (United States)

    Dabanch, Jeannette; Nájera, Manuel; González, Claudia; Guerrero, Andrea; Olea, Andrea; Fasce, Rodrigo; Morales, Cecilia; Vega, Jeanette

    2011-01-01

    Pandemic (H1N1) 2009 affected Chile during the winter of 2009. The hospitalization rate was 0.56% overall and 3.47% for persons >60 years of age at risk for severe disease and death independent of concurrent conditions. Age >60 years was the major risk factor for death from pandemic (H1N1) 2009. PMID:21762580

  4. Eventos adversos pós-vacinação contra influenza pandêmica A (H1N1 2009 em crianças Adverse events following vaccination against pandemic influenza A (H1N1 2009 in children

    Directory of Open Access Journals (Sweden)

    Gisele Nepomuceno de Andrade

    2012-09-01

    Full Text Available O objetivo do estudo foi estimar a frequência e os fatores associados à ocorrência de eventos adversos pós-vacinação contra a influenza pandêmica A (H1N1 2009 em crianças com idade entre seis meses e dois anos. Participaram do estudo 156 crianças. Modelos multivariados de regressão de Cox foram construídos para avaliar a associação independente de cada covariável e a queixa de pelo menos um evento adverso. A força da associação foi medida pela hazard ratio e seus respectivos intervalos de 95% de confiança. Após a primeira dose, foi relatado algum tipo de evento adverso por 40,3% dos participantes e, após a segunda, por 35,5%. Os eventos sistêmicos foram mais frequentes que os locais, destaque para irritabilidade, diarreia e febre. As incidências de eventos adversos, no geral e sistêmicos, após a primeira dose, foram maiores nas crianças com doença concomitante/alergia em relação àquelas sem o agravo (HR = 3,43; IC95%: 1,34-8,77 e HR = 2,76; IC95%: 1,11-6,89. A maioria dos eventos foi de intensidade leve. Febre alta, vômito e diarreia motivaram a busca por serviços de saúde.The aim of this study was to estimate the frequency of adverse events following vaccination against pandemic influenza A (H1N1 2009 and associated factors in children from six months to two years of age (n = 156. Multivariate Cox regression was used to assess the independent associations between covariates and complaints of at least one adverse event. Strength of association was measured by hazard ratios and respective 95% confidence intervals. Following the first dose, 40.3% of parents reported one or more adverse events in their children, compared to 35.5% after the second dose. Systemic adverse events, specifically irritation, diarrhea, and fever, were more frequent than local reactions at the vaccination site. Incidence rates for adverse events in general and systemic reactions following the first dose were higher in children with

  5. Positive Selection on Hemagglutinin and Neuraminidase Genes of H1N1 Influenza Viruses

    LENUS (Irish Health Repository)

    Li, Wenfu

    2011-04-21

    Abstract Background Since its emergence in March 2009, the pandemic 2009 H1N1 influenza A virus has posed a serious threat to public health. To trace the evolutionary path of these new pathogens, we performed a selection-pressure analysis of a large number of hemagglutinin (HA) and neuraminidase (NA) gene sequences of H1N1 influenza viruses from different hosts. Results Phylogenetic analysis revealed that both HA and NA genes have evolved into five distinct clusters, with further analyses indicating that the pandemic 2009 strains have experienced the strongest positive selection. We also found evidence of strong selection acting on the seasonal human H1N1 isolates. However, swine viruses from North America and Eurasia were under weak positive selection, while there was no significant evidence of positive selection acting on the avian isolates. A site-by-site analysis revealed that the positively selected sites were located in both of the cleaved products of HA (HA1 and HA2), as well as NA. In addition, the pandemic 2009 strains were subject to differential selection pressures compared to seasonal human, North American swine and Eurasian swine H1N1 viruses. Conclusions Most of these positively and\\/or differentially selected sites were situated in the B-cell and\\/or T-cell antigenic regions, suggesting that selection at these sites might be responsible for the antigenic variation of the viruses. Moreover, some sites were also associated with glycosylation and receptor-binding ability. Thus, selection at these positions might have helped the pandemic 2009 H1N1 viruses to adapt to the new hosts after they were introduced from pigs to humans. Positive selection on position 274 of NA protein, associated with drug resistance, might account for the prevalence of drug-resistant variants of seasonal human H1N1 influenza viruses, but there was no evidence that positive selection was responsible for the spread of the drug resistance of the pandemic H1N1 strains.

  6. Occupational health impact of the 2009 H1N1 flu pandemic: surveillance of sickness absence.

    Science.gov (United States)

    Torá-Rocamora, Isabel; Delclos, George L; Martínez, José Miguel; Jardí, Josefina; Alberti, Constança; Manzanera, Rafael; Yasui, Yutaka; Clèries, Ramón; Tobías, Aurelio; Benavides, Fernando G

    2012-03-01

    Workplace absences due to illness can disrupt usual operations and increase costs for businesses. This study of sickness absence due to influenza and influenza-related illness presents a unique opportunity to characterise and measure the impact of the 2009 (H1N1) pandemic, by comparing trends during the pandemic to those of previous years, and adding this information to that obtained by traditional epidemiological surveillance systems. We compared the numbers of cases of sickness absence due to illness caused by influenza and influenza-related illness in 2007-2009, and in the first 3 months of 2010 in Catalonia (n=811 940) using a time series approach. Trends were examined by economic activity, age and gender. The weekly endemic-epidemic index (EEI) was calculated and its 95% CI obtained with the delta method, with observed and expected cases considered as independent random variables. Influenza activity peaked earlier in 2009 and yielded more cases than in previous years. Week 46 (in November 2009) had the highest number of new cases resulting in sickness absence (EEI 20.99; 95% CI 9.44 to 46.69). Women and the 'education, health and other social activities' sector were the most affected. Results indicate that the new H1N1 pandemic had a significant impact on business, with shifts in the timing of peak incidence, a doubling in the number of cases, and changes in the distribution of cases by economic activity sector and gender. Traditional epidemiological surveillance systems could benefit from the addition of information based on sickness absence data.

  7. Perceived risk, anxiety, and behavioural responses of the general public during the early phase of the Influenza A (H1N1 pandemic in the Netherlands: results of three consecutive online surveys

    Directory of Open Access Journals (Sweden)

    van Steenbergen Jim E

    2011-01-01

    Full Text Available Abstract Background Research into risk perception and behavioural responses in case of emerging infectious diseases is still relatively new. The aim of this study was to examine perceptions and behaviours of the general public during the early phase of the Influenza A (H1N1 pandemic in the Netherlands. Methods Two cross-sectional and one follow-up online survey (survey 1, 30 April-4 May; survey 2, 15-19 June; survey 3, 11-20 August 2009. Adults aged 18 years and above participating in a representative Internet panel were invited (survey 1, n = 456; survey 2, n = 478; follow-up survey 3, n = 934. Main outcome measures were 1 time trends in risk perception, feelings of anxiety, and behavioural responses (survey 1-3 and 2 factors associated with taking preventive measures and strong intention to comply with government-advised preventive measures in the future (survey 3. Results Between May and August 2009, the level of knowledge regarding Influenza A (H1N1 increased, while perceived severity of the new flu, perceived self-efficacy, and intention to comply with preventive measures decreased. The perceived reliability of information from the government decreased from May to August (62% versus 45%. Feelings of anxiety decreased from May to June, and remained stable afterwards. From June to August 2009, perceived vulnerability increased and more respondents took preventive measures (14% versus 38%. Taking preventive measures was associated with no children in the household, high anxiety, high self-efficacy, more agreement with statements on avoidance, and paying much attention to media information regarding Influenza A (H1N1. Having a strong intention to comply with government-advised preventive measures in the future was associated with higher age, high perceived severity, high anxiety, high perceived efficacy of measures, high self-efficacy, and finding governmental information to be reliable. Conclusions Decreasing trends over time in perceived

  8. Asymptomatic ratio for seasonal H1N1 influenza infection among schoolchildren in Taiwan.

    Science.gov (United States)

    Hsieh, Ying-Hen; Tsai, Chen-An; Lin, Chien-Yu; Chen, Jin-Hua; King, Chwan-Chuen; Chao, Day-Yu; Cheng, Kuang-Fu

    2014-02-12

    Studies indicate that asymptomatic infections do indeed occur frequently for both seasonal and pandemic influenza, accounting for about one-third of influenza infections. Studies carried out during the 2009 pH1N1 pandemic have found significant antibody response against seasonal H1N1 and H3N2 vaccine strains in schoolchildren receiving only pandemic H1N1 monovalent vaccine, yet reported either no symptoms or only mild symptoms. Serum samples of 255 schoolchildren, who had not received vaccination and had pre-season HI Ab serotiters definition of Fever + (cough or sore throat or nose) + ( headache or pain or fatigue). Asymptomatic ratio for children is found to be substantially higher than that of the general population in literature. In providing reasonable quantification of the asymptomatic infected children spreading pathogens to others in a seasonal epidemic or a pandemic, our estimates of symptomatic ratio of infected children has important clinical and public health implications.

  9. Community-based measures for mitigating the 2009 H1N1 pandemic in China.

    Directory of Open Access Journals (Sweden)

    Sanyi Tang

    Full Text Available Since the emergence of influenza A/H1N1 pandemic virus in March-April 2009, very stringent interventions including Fengxiao were implemented to prevent importation of infected cases and decelerate the disease spread in mainland China. The extent to which these measures have been effective remains elusive. We sought to investigate the effectiveness of Fengxiao that may inform policy decisions on improving community-based interventions for management of on-going outbreaks in China, in particular during the Spring Festival in mid-February 2010 when nationwide traveling will be substantially increased. We obtained data on initial laboratory-confirmed cases of H1N1 in the province of Shaanxi and used Markov-chain Monte-Carlo (MCMC simulations to estimate the reproduction number. Given the estimates for the exposed and infectious periods of the novel H1N1 virus, we estimated a mean reproduction number of 1.68 (95% CI 1.45-1.92 and other A/H1N1 epidemiological parameters. Our results based on a spatially stratified population dynamical model show that the early implementation of Fengxiao can delay the epidemic peak significantly and prevent the disease spread to the general population but may also, if not implemented appropriately, cause more severe outbreak within universities/colleges, while late implementation of Fengxiao can achieve nothing more than no implementation. Strengthening local control strategies (quarantine and hygiene precaution is much more effective in mitigating outbreaks and inhibiting the successive waves than implementing Fengxiao. Either strong mobility or high transport-related transmission rate during the Spring Festival holiday will not reverse the ongoing outbreak, but both will result in a large new wave. The findings suggest that Fengxiao and travel precautions should not be relaxed unless strict measures of quarantine, isolation, and hygiene precaution practices are put in place. Integration and prompt impleme