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Edler P, Schwab LSU, Aban M, Wille M, Spirason N, Deng YM, Carlock MA, Ross TM, Juno JA, Rockman S, Wheatley AK, Kent SJ, Barr IG, Price DJ, Koutsakos M. Immune imprinting in early life shapes cross-reactivity to influenza B virus haemagglutinin. Nat Microbiol 2024; 9:2073-2083. [PMID: 38890491 DOI: 10.1038/s41564-024-01732-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 05/15/2024] [Indexed: 06/20/2024]
Abstract
Influenza exposures early in life are believed to shape future susceptibility to influenza infections by imprinting immunological biases that affect cross-reactivity to future influenza viruses. However, direct serological evidence linked to susceptibility is limited. Here we analysed haemagglutination-inhibition titres in 1,451 cross-sectional samples collected between 1992 and 2020, from individuals born between 1917 and 2008, against influenza B virus (IBV) isolates from 1940 to 2021. We included testing of 'future' isolates that circulated after sample collection. We show that immunological biases are conferred by early life IBV infection and result in lineage-specific cross-reactivity of a birth cohort towards future IBV isolates. This translates into differential estimates of susceptibility between birth cohorts towards the B/Yamagata and B/Victoria lineages, predicting lineage-specific birth-cohort distributions of observed medically attended IBV infections. Our data suggest that immunological measurements of imprinting could be important in modelling and predicting virus epidemiology.
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Affiliation(s)
- Peta Edler
- Department of Infectious Diseases, University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
| | - Lara S U Schwab
- Department of Microbiology and Immunology, University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
| | - Malet Aban
- WHO Collaborating Centre for Reference and Research on Influenza, Royal Melbourne Hospital, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Michelle Wille
- WHO Collaborating Centre for Reference and Research on Influenza, Royal Melbourne Hospital, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
- Centre for Pathogen Genomics, University of Melbourne, Melbourne, Victoria, Australia
| | - Natalie Spirason
- WHO Collaborating Centre for Reference and Research on Influenza, Royal Melbourne Hospital, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Yi-Mo Deng
- WHO Collaborating Centre for Reference and Research on Influenza, Royal Melbourne Hospital, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Michael A Carlock
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, USA
- Department of Infectious Diseases, University of Georgia, Athens, GA, USA
- Florida Research and Innovation Centre, Cleveland Clinic, Port Saint Lucie, FL, USA
| | - Ted M Ross
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, USA
- Department of Infectious Diseases, University of Georgia, Athens, GA, USA
- Florida Research and Innovation Centre, Cleveland Clinic, Port Saint Lucie, FL, USA
- Department of Infection Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Jennifer A Juno
- Department of Microbiology and Immunology, University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
| | - Steve Rockman
- Department of Microbiology and Immunology, University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
- Vaccine Product Development, CSL Seqirus Ltd, Parkville, Victoria, Australia
| | - Adam K Wheatley
- Department of Microbiology and Immunology, University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
| | - Stephen J Kent
- Department of Microbiology and Immunology, University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
- Melbourne Sexual Health Centre and Department of Infectious Diseases, Alfred Health, Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - Ian G Barr
- Department of Microbiology and Immunology, University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
- WHO Collaborating Centre for Reference and Research on Influenza, Royal Melbourne Hospital, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - David J Price
- Department of Infectious Diseases, University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
- Centre for Epidemiology & Biostatistics, Melbourne School of Population & Global Health, The University of Melbourne, Melbourne, Victoria, Australia
| | - Marios Koutsakos
- Department of Microbiology and Immunology, University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia.
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Abo Shama NM, Mahmoud SH, Bagato O, AbdElsalam ET, Alkhazindar M, Kandeil A, McKenzie PP, Webby RJ, Ali MA, Kayali G, El-Shesheny R. Incidence and neutralizing antibody seroprevalence of influenza B virus in Egypt: Results of a community-based cohort study. PLoS One 2022; 17:e0269321. [PMID: 35767564 PMCID: PMC9242516 DOI: 10.1371/journal.pone.0269321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 05/19/2022] [Indexed: 11/27/2022] Open
Abstract
Since 2000, two lineages of influenza B viruses, Victoria and Yamagata, have been circulating at similar frequencies worldwide. Little is known about the circulation of those viruses in Egypt. This study aims to describe the epidemiology of influenza B virus infections in Egypt, 2017–2019. This was performed through a household prospective cohort study on influenza infections among 2400 individuals from five villages. When a study participant had influenza like symptoms, a nasal swab and an oropharyngeal swab were obtained and tested by RT-PCR for influenza B infections. A serum sample was obtained from all participants annually to detect neutralizing antibodies using microneutralization assay. 9.1% of subjects were positive for influenza B viruses during season 2017–2018 mostly among preschoolers and 7.6% were positive during the season 2018–2019 with higher risk in females, potentially due to mothers being infected after contact with their children. The overall seroprevalence among the participants was 53.2% and 52.2% against the Victoria and Yamagata lineages respectively, the majority of seropositive participants were students. Multivariate analysis showed that age and having chronic diseases were the strongest predictors of infection. Our results show that both influenza B lineages circulated between 2017 and 2020 in Egypt almost in equal proportion. Encouraging the uptake of seasonal influenza vaccines is recommended.
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Affiliation(s)
- Noura M. Abo Shama
- Center of Scientific Excellence for Influenza Virus, Environmental Research Division, National Research Centre, Giza, Egypt
| | - Sara H. Mahmoud
- Center of Scientific Excellence for Influenza Virus, Environmental Research Division, National Research Centre, Giza, Egypt
| | - Ola Bagato
- Center of Scientific Excellence for Influenza Virus, Environmental Research Division, National Research Centre, Giza, Egypt
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Riems, Germany
| | - Elsayed Tarek AbdElsalam
- Department of Botany and Microbiology, Faculty of Science, Cairo University, Gamaa Street, Giza, Egypt
| | - Maha Alkhazindar
- Department of Botany and Microbiology, Faculty of Science, Cairo University, Gamaa Street, Giza, Egypt
| | - Ahmed Kandeil
- Center of Scientific Excellence for Influenza Virus, Environmental Research Division, National Research Centre, Giza, Egypt
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, TN, United States of America
| | - Pamela P. McKenzie
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, TN, United States of America
| | - Richard J. Webby
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, TN, United States of America
| | - Mohamed A. Ali
- Center of Scientific Excellence for Influenza Virus, Environmental Research Division, National Research Centre, Giza, Egypt
| | | | - Rabeh El-Shesheny
- Center of Scientific Excellence for Influenza Virus, Environmental Research Division, National Research Centre, Giza, Egypt
- * E-mail: (GK); (RE)
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Salazar RA, Field SS. Factors Influencing Frequency of Pediatric Clinically Distinguishable Influenza: A 2 Season Case-Control Study. Clin Med Insights Pediatr 2022; 16:11795565221084159. [PMID: 35355882 PMCID: PMC8958712 DOI: 10.1177/11795565221084159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 02/03/2022] [Indexed: 11/24/2022] Open
Abstract
Background: Little is known about the individual differences in susceptibility to, or lifetime frequency of clinically distinguishable influenza in children. Methods: Rapid enzyme linked immunoassay-confirmed influenza pediatric cases (n = 96) in season 1 (2017-2018) were compared to age-matched (mean 7.7 years) controls (n = 171) with no evidence of influenza in season 1. The 2 cohorts were again studied in season 2 (2018-2019) for influenza outcomes and influences. Medical records, questionnaires, and interviews were used to determine past influenza disease and vaccine histories. Results: After season 2, known lifetime influenza illnesses per year of age averaged 22.6% in cases and 5.6% in controls, with 62% of controls still having never experienced known influenza. Having had prior influenza was marginally significant as a risk for season 1 influenza in cases versus controls (P = .055), yet a significant risk factor in controls for season 2 (P = .018). Influenza vaccine rates were significantly higher in controls than in cases for season 1, with a greater female vaccine benefit. Lack of previous influenza had greater calculated effectiveness (52%) than vaccination (17%-26%) in escaping season 2 influenza. Lifetime rates of vaccination did not correlate with lifetime rates of known influenza in either cohort. Conclusions: Lifetime clinically distinguishable influenza rates varied among children, with many escaping it for years even without being immunized against it. Findings of less than expected clinical influenza, no correlation between vaccination frequency and disease frequency, sex differences, and an association between past clinical influenza and current risk, point to innate differences in individual influenza experiences.
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Affiliation(s)
- Ryan A Salazar
- University of Alabama at Birmingham School of Medicine (Medical Student), Huntsville, AL, USA
| | - Scott S Field
- Department of Pediatrics, University of Alabama at Birmingham, Huntsville Campus (Adjunct Faculty), Huntsville, AL, USA
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Wang JL, Chen T, Deng LL, Han YJ, Wang DY, Wang LP, He GX. Epidemiological characteristics of imported respiratory infectious diseases in China, 2014‒2018. Infect Dis Poverty 2022; 11:22. [PMID: 35246236 PMCID: PMC8895356 DOI: 10.1186/s40249-022-00944-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 02/02/2022] [Indexed: 11/18/2022] Open
Abstract
Background With the progress of globalization, international mobility increases, greatly facilitating cross-border transmission of respiratory infectious diseases (RIDs). This study aimed to analyze the epidemiological characteristics and factors influencing imported RIDs, with the goal of providing evidence to support adoption of high-tech, intelligent methods to early find imported RIDs and prevent their spread in China. Methods We obtained data of imported RIDs cases from 2014 to 2018 from the Inbound Sentinel Network of Customs and the National Notifiable Diseases Reporting System in China. We analyzed spatial, temporal, and population distribution characteristics of the imported RIDs. We developed an index to describe seasonality. Pearson correlation coefficients were used to examine associations between independent variables and imported cases. Data analyses and visualizations were conducted with R software. Results From a total of 1 409 265 253 inbound travelers, 31 732 (2.25/100 000) imported RIDs cases were reported. RIDs cases were imported from 142 countries and five continents. The incidence of imported RIDs was nearly 5 times higher in 2018 (2.81/100 000) than in 2014 (0.58/100 000). Among foreigners, incidence rates were higher among males (5.32/100 000), 0–14-year-olds (15.15/100 000), and cases originating in Oceania (11.10/100 000). The vast majority (90.3%) of imported RIDs were influenza, with seasonality consistent with annual seasonality of influenza. The spatial distribution of imported RIDs was different between Chinese citizens and foreigners. Increases in inbound travel volume and the number of influenza cases in source countries were associated with the number of imported RIDs. Conclusions Our study documented importation of RIDs into China from 142 countries. Inbound travel poses a significant risks bringing important RIDs to China. It is urgent to strengthen surveillance at customs of inbound travelers and establish an intelligent surveillance and early warning system to prevent importation of RIDs to China for preventing further spread within China. Graphical Abstract ![]()
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Affiliation(s)
- Jin-Long Wang
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Tao Chen
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Le-Le Deng
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Ya-Jun Han
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Da-Yan Wang
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Li-Ping Wang
- Division of Infectious Diseases, Chinese Center for Disease Control and Prevention, Beijing, China.
| | - Guang-Xue He
- National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
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5
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Similar severity of influenza primary and re-infections in pre-school children requiring outpatient treatment due to febrile acute respiratory illness: prospective, multicentre surveillance study (2013-2015). BMC Infect Dis 2022; 22:12. [PMID: 34983428 PMCID: PMC8724639 DOI: 10.1186/s12879-021-06988-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 12/16/2021] [Indexed: 12/03/2022] Open
Abstract
Background Influenza virus infections in immunologically naïve children (primary infection) may be more severe than in children with re-infections who are already immunologically primed. We compared frequency and severity of influenza virus primary and re-infections in pre-school children requiring outpatient treatment. Methods Influenza-unvaccinated children 1–5 years of age presenting at pediatric practices with febrile acute respiratory infection < 48 h after symptom onset were enrolled in a prospective, cross-sectional, multicenter surveillance study (2013–2015). Influenza types/subtypes were PCR-confirmed from oropharyngeal swabs. Influenza type/subtype-specific IgG antibodies serving as surrogate markers for immunological priming were determined using ELISA/hemagglutination inhibition assays. The acute influenza disease was defined as primary infection/re-infection by the absence/presence of influenza type-specific immunoglobulin G (IgG) and, in a second approach, by the absence/presence of subtype-specific IgG. Socio-demographic and clinical data were also recorded. Results Of 217 influenza infections, 178 were due to influenza A (87 [49%] primary infections, 91 [51%] re-infections) and 39 were due to influenza B (38 [97%] primary infections, one [3%] re-infection). Children with “influenza A primary infections” showed fever with respiratory symptoms for a shorter period than children with “influenza A re-infections” (median 3 vs. 4 days; age-adjusted p = 0.03); other disease characteristics were similar. If primary infections and re-infections were defined based on influenza A subtypes, 122 (87%) primary infections (78 “A(H3N2) primary infections”, 44 “A(H1N1)pdm09 primary infections”) and 18 (13%) re-infections could be classified (14 “A(H3N2) re-infections” and 4 “A(H1N1)pdm09 re-infections”). Per subtype, primary infections and re-infections were of similar disease severity. Children with re-infections defined on the subtype level usually had non-protective IgG titers against the subtype of their acute infection (16 of 18; 89%). Some patients infected by one of the influenza A subtypes showed protective IgG titers (≥ 1:40) against the other influenza A subtype (32/140; 23%). Conclusions Pre-school children with acute influenza A primary infections and re-infections presented with similar frequency in pediatric practices. Contrary to expectation, severity of acute “influenza A primary infections” and “influenza A re-infections” were similar. Most “influenza A re-infections” defined on the type level turned out to be primary infections when defined based on the subtype. On the subtype level, re-infections were rare and of similar disease severity as primary infections of the same subtype. Subtype level re-infections were usually associated with low IgG levels for the specific subtype of the acute infection, suggesting only short-time humoral immunity induced by previous infection by this subtype. Overall, the results indicated recurring influenza virus infections in this age group and no or only limited heterosubtypic antibody-mediated cross-protection. Supplementary Information The online version contains supplementary material available at 10.1186/s12879-021-06988-7.
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Sun Y, Yang P, Wang Q, Zhang L, Duan W, Pan Y, Wu S, Wang H. Influenza Vaccination and Non-Pharmaceutical Measure Effectiveness for Preventing Influenza Outbreaks in Schools: A Surveillance-Based Evaluation in Beijing. Vaccines (Basel) 2020; 8:E714. [PMID: 33271800 PMCID: PMC7712374 DOI: 10.3390/vaccines8040714] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/17/2020] [Accepted: 11/20/2020] [Indexed: 11/16/2022] Open
Abstract
Although schools are known to play a major role in the spread of influenza virus, few studies have evaluated the effectiveness of vaccination and non-pharmaceutical measures for preventing influenza outbreaks in schools. We investigated all febrile illness outbreaks in primary and secondary schools in Beijing reported between August 2018 and July 2019. We obtained epidemiological information on febrile illness outbreaks and oral pharyngeal swabs from students in the outbreaks to test for influenza virus. We surveyed schools that did not report febrile illness outbreaks. We developed multi-level models to identify and evaluate factors associated with serious influenza outbreaks and explored the association of vaccine coverage and outbreaks using multi-stage regression models. We identified a total of 748 febrile illness outbreaks involving 8176 students in Beijing; 462 outbreaks were caused by influenza virus. Adjusted regression modeling showed that large class size (odds ratio (OR) = 2.38) and the number of days from identification of the first case to initiation of an intervention (OR = 1.17) were statistically significant and positively associated with serious outbreaks, and that high vaccination coverage (relative risk (RR) = 0.50) was statistically significant and negatively associated with outbreaks. Multi-stage regression modeling showed that RR decreased fastest when vaccination coverage was 45% to 51%. We conclude that high influenza vaccination coverage can prevent influenza outbreaks in schools and that rapid identification of febrile children and early initiation of non-pharmaceutical measures can reduce outbreak size.
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Affiliation(s)
- Ying Sun
- Department of National Immunization Program, Chinese Center for Disease Control and Prevention, Beijing 100050, China;
- Institute for Infectious Diseases and Endemic Diseases Prevention and Control, Beijing Center for Disease Prevention and Control (CDC), Beijing 100013, China; (Q.W.); (L.Z.); (W.D.); (Y.P.); (S.W.)
| | - Peng Yang
- Office of Beijing Center for Global Health, Beijing Center for Diseases Prevention and Control (CDC), Beijing 100013, China;
- School of Public Health, Capital Medical University, Beijing 100069, China
| | - Quanyi Wang
- Institute for Infectious Diseases and Endemic Diseases Prevention and Control, Beijing Center for Disease Prevention and Control (CDC), Beijing 100013, China; (Q.W.); (L.Z.); (W.D.); (Y.P.); (S.W.)
| | - Li Zhang
- Institute for Infectious Diseases and Endemic Diseases Prevention and Control, Beijing Center for Disease Prevention and Control (CDC), Beijing 100013, China; (Q.W.); (L.Z.); (W.D.); (Y.P.); (S.W.)
| | - Wei Duan
- Institute for Infectious Diseases and Endemic Diseases Prevention and Control, Beijing Center for Disease Prevention and Control (CDC), Beijing 100013, China; (Q.W.); (L.Z.); (W.D.); (Y.P.); (S.W.)
| | - Yang Pan
- Institute for Infectious Diseases and Endemic Diseases Prevention and Control, Beijing Center for Disease Prevention and Control (CDC), Beijing 100013, China; (Q.W.); (L.Z.); (W.D.); (Y.P.); (S.W.)
| | - Shuangsheng Wu
- Institute for Infectious Diseases and Endemic Diseases Prevention and Control, Beijing Center for Disease Prevention and Control (CDC), Beijing 100013, China; (Q.W.); (L.Z.); (W.D.); (Y.P.); (S.W.)
| | - Huaqing Wang
- Department of National Immunization Program, Chinese Center for Disease Control and Prevention, Beijing 100050, China;
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Falcón-Lezama JA, Saucedo-Martínez R, Betancourt-Cravioto M, Alfaro-Cortes MM, Bahena-González RI, Tapia-Conyer R. Influenza in the school-aged population in Mexico: burden of disease and cost-effectiveness of vaccination in children. BMC Infect Dis 2020; 20:240. [PMID: 32197591 PMCID: PMC7085158 DOI: 10.1186/s12879-020-4948-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 03/04/2020] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The current national influenza vaccination schedule in Mexico does not recommend vaccination in the school-aged population (5-11 years). Currently, there are limited data from middle-income countries analysing the cost-effectiveness of influenza vaccination in this population. We explored the clinical effects and economic benefits of expanding the current national influenza vaccination schedule in Mexico to include the school-aged population. METHODS A static 1-year model incorporating herd effect was used to assess the cost-effectiveness of expanding the current national influenza vaccination schedule of Mexico to include the school-aged population. We performed a cross-sectional epidemiological study using influenza records (2009-2018), death records (2010-2015), and discharge and hospitalisation records (2010-2016), from the databases of Mexico's Influenza Surveillance System (SISVEFLU), the National Mortality Epidemiological and Statistical System (SEED), and the Automated Hospital Discharge System (SAEH), respectively. Cost estimates for influenza cases were based on 7 scenarios using data analysed from SISVEFLU; assumptions for clinical management of cases were defined according to Mexico's national clinical guidelines. The primary health outcome for this study was the number of influenza cases avoided. A sensitivity analysis was performed using conservative and optimistic parameters (vaccination coverage: 30% / 70%, Vaccine effectiveness: 19% / 68%). RESULTS It was estimated that expanding the influenza immunisation programme to cover school-aged population in Mexico over the 2018-2019 influenza season would result in 671,461 cases of influenza avoided (50% coverage and 50% effectiveness assumed). Associated with this were 262,800 fewer outpatient consultations; 154,100 fewer emergency room consultations; 97,600 fewer hospitalisations, and 15 fewer deaths. Analysis of cases avoided by age-group showed that 55.4% of them were in the school-aged population, and the decrease in outpatient consultations was largest in this population. There was an overall decrease in the economic burden for the Mexican health care system of 111.9 million US dollars; the immunization programme was determined to be cost-saving in the base, conservative and optimistic scenarios. CONCLUSIONS Vaccinating school-aged population in Mexico would be cost-effective; expansion of the current national vaccination schedule to this age group is supported.
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Affiliation(s)
| | - Rodrigo Saucedo-Martínez
- Sociedad Mexicana de Salud Pública, Herschel 109, Anzures, Miguel Hidalgo, 11590, Mexico City, Mexico
| | | | - Myrna María Alfaro-Cortes
- Sociedad Mexicana de Salud Pública, Herschel 109, Anzures, Miguel Hidalgo, 11590, Mexico City, Mexico
| | | | - Roberto Tapia-Conyer
- Sociedad Mexicana de Salud Pública, Herschel 109, Anzures, Miguel Hidalgo, 11590, Mexico City, Mexico.
- Universidad Nacional Autónoma de México, Av. Universidad 3000, Circuito Escolar CU, Edificio B 1er Piso, Coyoacan, 04510, Mexico City, Mexico.
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Zhang L, van der Hoek W, Krafft T, Pilot E, Asten LV, Lin G, Wu S, Duan W, Yang P, Wang Q. Influenza vaccine effectiveness estimates against influenza A(H3N2) and A(H1N1) pdm09 among children during school-based outbreaks in the 2016-2017 season in Beijing, China. Hum Vaccin Immunother 2019; 16:816-822. [PMID: 31596661 DOI: 10.1080/21645515.2019.1677438] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Background: Since 2007, trivalent inactivated influenza vaccine (TIV) has been provided free-of-charge to primary, middle school and high school students in Beijing. However, there have been few school-based studies on influenza vaccine effectiveness (VE). In this report, we estimated influenza VE against laboratory-confirmed influenza illness among school children in Beijing, China during the 2016-2017 influenza season.Methods: The VE of 2016-2017 TIV against laboratory-confirmed influenza virus infection among school-age children was assessed through a case-control design. Conditional logistic regression was conducted on matched case-control sets to estimate VE. The effect of prior vaccination on current VE was also examined.Results: All 176 samples tested positive for influenza A virus with the positive rate of 55.5%. The average coverage rate of 2016-2017 TIV among students across the 37 schools was 30.6%. The fully adjusted VE of 2016-2017 TIV against laboratory-confirmed influenza was 69% (95% CI: 51 to 81): 60% (95% CI: -15 to 86) for influenza A(H1N1)pdm09 and 73% (95% CI: 52 to 84) for influenza A(H3N2). The overall VE for receipt of 2015-2016 vaccination only, 2016-2017 vaccination only, and vaccinations in both seasons was 46% (95% CI: -5 to 72), 77% (95% CI: 58 to 87), and 57% (95%CI: 17 to 78), respectively.Conclusions: Our study during school outbreaks found that VE of 2016-2017 TIV was moderate against influenza A(H3N2) as well as A(H1N1)pdm09 viruses.
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Affiliation(s)
- Li Zhang
- Institute for Infectious Disease and Endemic Disease Control, Beijing Center for Disease Prevention and Control, Beijing, China.,Beijing Research Center for Preventive Medicine, Beijing, China
| | - Wim van der Hoek
- Centre for Infectious Diseases, Epidemiology and Surveillance, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Thomas Krafft
- Department of Health, Ethics & Society, CAPHRI Care and Public Health Research Institute, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Eva Pilot
- Department of Health, Ethics & Society, CAPHRI Care and Public Health Research Institute, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Liselotte van Asten
- Centre for Infectious Diseases, Epidemiology and Surveillance, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Ge Lin
- Department of Environmental and Occupational Health, School of Public Health, University of Nevada Las Vegas, Las Vegas, NV, USA
| | - Shuangsheng Wu
- Institute for Infectious Disease and Endemic Disease Control, Beijing Center for Disease Prevention and Control, Beijing, China.,Beijing Research Center for Preventive Medicine, Beijing, China
| | - Wei Duan
- Institute for Infectious Disease and Endemic Disease Control, Beijing Center for Disease Prevention and Control, Beijing, China.,Beijing Research Center for Preventive Medicine, Beijing, China
| | - Peng Yang
- Institute for Infectious Disease and Endemic Disease Control, Beijing Center for Disease Prevention and Control, Beijing, China.,Beijing Research Center for Preventive Medicine, Beijing, China.,School of Public Health, Capital Medical University, Beijing, China
| | - Quanyi Wang
- Institute for Infectious Disease and Endemic Disease Control, Beijing Center for Disease Prevention and Control, Beijing, China.,Beijing Research Center for Preventive Medicine, Beijing, China
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Subtype-specific Clinical Presentation, Medical Treatment and Family Impact of Influenza in Children 1-5 Years of Age Treated in Outpatient Practices in Germany During Three Postpandemic Years, 2013-2015. Pediatr Infect Dis J 2018; 37:861-867. [PMID: 29406467 DOI: 10.1097/inf.0000000000001935] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Limited data on the influenza burden in pediatric outpatients are available, especially regarding direct comparison of the cocirculating (sub)types A(H1N1)pdm09, A(H3N2) and B. METHODS Children 1-5 years of age, unvaccinated against influenza and presenting with febrile acute respiratory infections (ARIs), were enrolled in 33 pediatric practices in Germany from 2013 to 2015 (January-May). Influenza was confirmed by multiplex polymerase chain reaction from pharyngeal swabs and (sub)typed. RESULTS In 805 children with ARI, influenza was the most frequently detected respiratory virus (n = 305; 37.9%). Of 217 influenza patients included, 122 (56.2%) were infected with A(H3N2), 56 (25.8%) with A(H1N1)pdm09 and 39 (18.0%) with B. Median age was 3.7 years [interquartile range (IQR), 2.1-4.8]; 11% had underlying conditions. Median fever duration was 4 days (IQR, 3-5), and the disease duration was 9 days (IQR, 7-12). Most frequent diagnoses were pharyngitis (26%), bronchitis (18%) and acute otitis media (10%). Children received mainly antipyretics (86%) and adrenergic nasal drops/spray (53%); 9% received antibiotics and 3% oseltamivir. Thirty-six percent required at least 1 additional practice visit; 1% was hospitalized. Median absences from childcare were 5 days (IQR, 3-7); parents lost 4 workdays (IQR, 2-6). Symptoms, severity and impact on the family were largely unrelated to (sub)type. However, patients with A(H1N1)pdm09 had fewer underlying conditions (P = 0.017), whereas patients with B more often had pharyngitis (P = 0.022), acute otitis media (P = 0.012) and stenosing laryngotracheitis (P = 0.007). CONCLUSIONS Influenza was the most frequently detected viral pathogen in outpatient children with febrile, mostly uncomplicated ARI. In this setting, clinical manifestations and severity were similar across the (sub)types prevalent during the postpandemic seasons.
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10
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Sanou AM, Wandaogo SCM, Poda A, Tamini L, Kyere AE, Sagna T, Ouedraogo MS, Pauly M, Hübschen JM, Muller CP, Tarnagda Z, Snoeck CJ. Epidemiology and molecular characterization of influenza viruses in Burkina Faso, sub-Saharan Africa. Influenza Other Respir Viruses 2018; 12:490-496. [PMID: 29350841 PMCID: PMC6005621 DOI: 10.1111/irv.12539] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/03/2018] [Indexed: 01/08/2023] Open
Abstract
Background The importance of influenza viruses in respiratory infections in sub‐Saharan Africa has been historically overlooked, including in Burkina Faso. Objectives This study therefore aimed at evaluating the prevalence and seasonal occurrence of influenza viruses in children under 5 years old, at risk of influenza‐related complications, presenting with influenza‐like illness (ILI) or severe acute respiratory infection (SARI). The study also aimed at identifying the periods with increased influenza transmission for vaccination recommendations in Burkina Faso. Methods From January 2014 to December 2015, ILI and SARI (2015 only) patients were recruited in six healthcare centers in Burkina Faso. Influenza A and B molecular detection and subtyping were performed. Clade clustering of a subset of A(H1N1)pdm09 and A(H3N2) strains was deduced by performing phylogenetic analyses on hemagglutinin gene sequences. Weekly surveillance data from FluNet (2011‐2013; 2016) and this study (2014‐2015) were used to identify periods of increased influenza activity. Results Influenza A and B viruses were detected in 15.1% (112 of 743) of ILI and 6.6% (12 of 181) of SARI patients. Overall, influenza A viruses were largely predominant (81 of 124, 65.3%), with 69.1% of A(H3N2) and 30.9% of A(H1N1)pdm09 strains. Four waves of increased transmission were identified in 2014‐2015, each dominated by different influenza subtypes and clades. Between 2011 and 2016, periods of increased influenza activity varied in their frequency, duration, and timing. Conclusion Influenza A and B viruses were detected in a substantial number of ILI and SARI cases in Burkina Faso. Vaccination in September‐October would likely protect the highest number of patients.
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Affiliation(s)
- Armel M Sanou
- National Influenza Reference Laboratory, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Sampoko Carine M Wandaogo
- National Influenza Reference Laboratory, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Armel Poda
- Hôpital du jour, Service des maladies infectieuses, CHU Souro Sanou, Bobo-Dioulasso, Burkina Faso.,Université Polytechnique de Bobo-Dioulasso (UPB), Bobo-Dioulasso, Burkina Faso
| | - Laure Tamini
- Service de Pédiatrie, CHU Pédiatrique Charles De Gaulles, Ouagadougou, Burkina Faso.,Unité de Formation et de Recherche en Sciences de la Santé (UFR/SDS), Université de Ouagadougou, Ouagadougou, Burkina Faso
| | - Anselme E Kyere
- National Influenza Reference Laboratory, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Tani Sagna
- National Influenza Reference Laboratory, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Macaire S Ouedraogo
- Hôpital du jour, Service des maladies infectieuses, CHU Souro Sanou, Bobo-Dioulasso, Burkina Faso.,Université Polytechnique de Bobo-Dioulasso (UPB), Bobo-Dioulasso, Burkina Faso
| | - Maude Pauly
- Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
| | - Judith M Hübschen
- Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
| | - Claude P Muller
- Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
| | - Zekiba Tarnagda
- National Influenza Reference Laboratory, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Chantal J Snoeck
- Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
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11
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Wen F, Bedford T, Cobey S. Explaining the geographical origins of seasonal influenza A (H3N2). Proc Biol Sci 2017; 283:rspb.2016.1312. [PMID: 27629034 PMCID: PMC5031657 DOI: 10.1098/rspb.2016.1312] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 08/24/2016] [Indexed: 12/17/2022] Open
Abstract
Most antigenically novel and evolutionarily successful strains of seasonal influenza A (H3N2) originate in East, South and Southeast Asia. To understand this pattern, we simulated the ecological and evolutionary dynamics of influenza in a host metapopulation representing the temperate north, tropics and temperate south. Although seasonality and air traffic are frequently used to explain global migratory patterns of influenza, we find that other factors may have a comparable or greater impact. Notably, a region's basic reproductive number (R0) strongly affects the antigenic evolution of its viral population and the probability that its strains will spread and fix globally: a 17-28% higher R0 in one region can explain the observed patterns. Seasonality, in contrast, increases the probability that a tropical (less seasonal) population will export evolutionarily successful strains but alone does not predict that these strains will be antigenically advanced. The relative sizes of different host populations, their birth and death rates, and the region in which H3N2 first appears affect influenza's phylogeography in different but relatively minor ways. These results suggest general principles that dictate the spatial dynamics of antigenically evolving pathogens and offer predictions for how changes in human ecology might affect influenza evolution.
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Affiliation(s)
- Frank Wen
- Department of Ecology and Evolution, University of Chicago, 1101 East 57th Street, Chicago, IL 60637, USA
| | - Trevor Bedford
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Sarah Cobey
- Department of Ecology and Evolution, University of Chicago, 1101 East 57th Street, Chicago, IL 60637, USA
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12
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Gostic KM, Ambrose M, Worobey M, Lloyd-Smith JO. Potent protection against H5N1 and H7N9 influenza via childhood hemagglutinin imprinting. Science 2016; 354:722-726. [PMID: 27846599 PMCID: PMC5134739 DOI: 10.1126/science.aag1322] [Citation(s) in RCA: 324] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 10/03/2016] [Indexed: 01/02/2023]
Abstract
Two zoonotic influenza A viruses (IAV) of global concern, H5N1 and H7N9, exhibit unexplained differences in age distribution of human cases. Using data from all known human cases of these viruses, we show that an individual's first IAV infection confers lifelong protection against severe disease from novel hemagglutinin (HA) subtypes in the same phylogenetic group. Statistical modeling shows that protective HA imprinting is the crucial explanatory factor, and it provides 75% protection against severe infection and 80% protection against death for both H5N1 and H7N9. Our results enable us to predict age distributions of severe disease for future pandemics and demonstrate that a novel strain's pandemic potential increases yearly when a group-mismatched HA subtype dominates seasonal influenza circulation. These findings open new frontiers for rational pandemic risk assessment.
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MESH Headings
- Age Factors
- Animals
- Child
- Genomic Imprinting
- Global Health
- Hemagglutinin Glycoproteins, Influenza Virus/genetics
- Hemagglutinin Glycoproteins, Influenza Virus/immunology
- Humans
- Influenza A Virus, H5N1 Subtype/genetics
- Influenza A Virus, H5N1 Subtype/immunology
- Influenza A Virus, H7N9 Subtype/genetics
- Influenza A Virus, H7N9 Subtype/immunology
- Influenza, Human/epidemiology
- Influenza, Human/immunology
- Influenza, Human/virology
- Models, Statistical
- Pandemics/statistics & numerical data
- Risk Assessment
- Zoonoses/epidemiology
- Zoonoses/virology
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Affiliation(s)
- Katelyn M Gostic
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Monique Ambrose
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Michael Worobey
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA.
| | - James O Lloyd-Smith
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA 90095, USA.
- Fogarty International Center, National Institutes of Health, Bethesda, MD 20892, USA
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13
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Knuf M, Kunze A. Influenza. Monatsschr Kinderheilkd 2016. [DOI: 10.1007/s00112-016-0182-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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14
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Thorrington D, Jit M, Eames K. Targeted vaccination in healthy school children - Can primary school vaccination alone control influenza? Vaccine 2015; 33:5415-5424. [PMID: 26314627 DOI: 10.1016/j.vaccine.2015.08.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 07/12/2015] [Accepted: 08/12/2015] [Indexed: 11/19/2022]
Abstract
BACKGROUND The UK commenced an extension to the seasonal influenza vaccination policy in autumn 2014 that will eventually see all healthy children between the ages of 2-16 years offered annual influenza vaccination. Models suggest that the new policy will be both highly effective at reducing the burden of influenza as well as cost-effective. We explore whether targeting vaccination at either primary or secondary schools would be more effective and/or cost-effective than the current strategy. METHODS An age-structured deterministic transmission dynamic SEIR-type mathematical model was used to simulate a national influenza outbreak in England. Costs including GP consultations, hospitalisations due to influenza and vaccinations were compared to potential gains in quality-adjusted life years achieved through vaccinating healthy children. Costs and benefits of the new JCVI vaccination policy were estimated over a single season, and compared to the hypothesised new policies of targeted and heterogeneous vaccination. FINDINGS AND CONCLUSION All potential vaccination policies were highly cost-effective. Influenza transmission can be eliminated for a particular season by vaccinating both primary and secondary school children, but not by vaccinating only one group. The most cost-effective policy overall is heterogeneous vaccination coverage with 48% uptake in primary schools and 34% in secondary schools. The Joint Committee on Vaccination and Immunisation can consider a modification to their policy of offering seasonal influenza vaccinations to all healthy children of ages 2-16 years.
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Affiliation(s)
- Dominic Thorrington
- Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, London, UK.
| | - Mark Jit
- Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, London, UK; Modelling and Economics Unit, Public Health England, London, UK
| | - Ken Eames
- Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, London, UK
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15
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Feng L, Yang P, Zhang T, Yang J, Fu C, Qin Y, Zhang Y, Ma C, Liu Z, Wang Q, Zhao G, Yu H. Technical guidelines for the application of seasonal influenza vaccine in China (2014-2015). Hum Vaccin Immunother 2015; 11:2077-101. [PMID: 26042462 PMCID: PMC4635867 DOI: 10.1080/21645515.2015.1027470] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 03/05/2015] [Indexed: 10/23/2022] Open
Abstract
Influenza, caused by the influenza virus, is a respiratory infectious disease that can severely affect human health. Influenza viruses undergo frequent antigenic changes, thus could spread quickly. Influenza causes seasonal epidemics and outbreaks in public gatherings such as schools, kindergartens, and nursing homes. Certain populations are at risk for severe illness from influenza, including pregnant women, young children, the elderly, and people in any ages with certain chronic diseases.
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Affiliation(s)
- Luzhao Feng
- Key Laboratory of Surveillance and Early-warning on Infectious Disease; Division of Infectious Disease; Chinese Center for Disease Control and Prevention; Beijing, China
| | - Peng Yang
- Beijing Center for Disease Control and Prevention; Beijing, China
| | - Tao Zhang
- School of Public Health; Fudan University; Shanghai, China
| | - Juan Yang
- Key Laboratory of Surveillance and Early-warning on Infectious Disease; Division of Infectious Disease; Chinese Center for Disease Control and Prevention; Beijing, China
| | - Chuanxi Fu
- Guangzhou Center for Disease Control and Prevention; Guangzhou, China
| | - Ying Qin
- Key Laboratory of Surveillance and Early-warning on Infectious Disease; Division of Infectious Disease; Chinese Center for Disease Control and Prevention; Beijing, China
| | - Yi Zhang
- Beijing Center for Disease Control and Prevention; Beijing, China
| | - Chunna Ma
- Beijing Center for Disease Control and Prevention; Beijing, China
| | - Zhaoqiu Liu
- Hua Xin Hospital; First Hospital of Tsinghua University; Beijing, China
| | - Quanyi Wang
- Beijing Center for Disease Control and Prevention; Beijing, China
| | - Genming Zhao
- School of Public Health; Fudan University; Shanghai, China
| | - Hongjie Yu
- Key Laboratory of Surveillance and Early-warning on Infectious Disease; Division of Infectious Disease; Chinese Center for Disease Control and Prevention; Beijing, China
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16
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Sauerbrei A, Langenhan T, Brandstadt A, Schmidt-Ott R, Krumbholz A, Girschick H, Huppertz H, Kaiser P, Liese J, Streng A, Niehues T, Peters J, Sauerbrey A, Schroten H, Tenenbaum T, Wirth S, Wutzler P. Prevalence of antibodies against influenza A and B viruses in children in Germany, 2008 to 2010. ACTA ACUST UNITED AC 2014; 19. [PMID: 24524235 DOI: 10.2807/1560-7917.es2014.19.5.20687] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The prevalence of influenza A and B virus-specific IgG was determined in sera taken between 2008 and 2010 from 1,665 children aged 0-17 years and 400 blood donors in Germany. ELISA on the basis of whole virus antigens was applied. Nearly all children aged nine years and older had antibodies against influenza A. In contrast, 40% of children aged 0-4 years did not have any influenza A virus-specific IgG antibodies. Eightysix percent of 0-6 year-olds, 47% of 7-12 year-olds and 20% of 13-17 year-olds were serologically naïve to influenza B viruses. By the age of 18 years, influenza B seroprevalence reached approximately 90%. There were obvious regional differences in the seroprevalence of influenza B in Germany. In conclusion, seroprevalences of influenza A and influenza B increase gradually during childhood. The majority of children older than eight years have basal immunity to influenza A, while comparable immunity against influenza B is only acquired at the age of 18 years. Children aged 0-6 years, showing an overall seroprevalence of 67% for influenza A and of 14% for influenza B, are especially at risk for primary infections during influenza B seasons.
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Affiliation(s)
- A Sauerbrei
- Institute of Virology and Antiviral Therapy, Jena University Clinic, Friedrich Schiller University of Jena, Jena, Germany
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17
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Barclay VC, Smieszek T, He J, Cao G, Rainey JJ, Gao H, Uzicanin A, Salathé M. Positive network assortativity of influenza vaccination at a high school: implications for outbreak risk and herd immunity. PLoS One 2014; 9:e87042. [PMID: 24505274 PMCID: PMC3914803 DOI: 10.1371/journal.pone.0087042] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 12/17/2013] [Indexed: 11/18/2022] Open
Abstract
Schools are known to play a significant role in the spread of influenza. High vaccination coverage can reduce infectious disease spread within schools and the wider community through vaccine-induced immunity in vaccinated individuals and through the indirect effects afforded by herd immunity. In general, herd immunity is greatest when vaccination coverage is highest, but clusters of unvaccinated individuals can reduce herd immunity. Here, we empirically assess the extent of such clustering by measuring whether vaccinated individuals are randomly distributed or demonstrate positive assortativity across a United States high school contact network. Using computational models based on these empirical measurements, we further assess the impact of assortativity on influenza disease dynamics. We found that the contact network was positively assortative with respect to influenza vaccination: unvaccinated individuals tended to be in contact more often with other unvaccinated individuals than with vaccinated individuals, and these effects were most pronounced when we analyzed contact data collected over multiple days. Of note, unvaccinated males contributed substantially more than unvaccinated females towards the measured positive vaccination assortativity. Influenza simulation models using a positively assortative network resulted in larger average outbreak size, and outbreaks were more likely, compared to an otherwise identical network where vaccinated individuals were not clustered. These findings highlight the importance of understanding and addressing heterogeneities in seasonal influenza vaccine uptake for prevention of large, protracted school-based outbreaks of influenza, in addition to continued efforts to increase overall vaccine coverage.
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Affiliation(s)
- Victoria C. Barclay
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- * E-mail:
| | - Timo Smieszek
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Jianping He
- Department of Computer Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Guohong Cao
- Department of Computer Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Jeanette J. Rainey
- Division of Global Migration and Quarantine, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Hongjiang Gao
- Division of Global Migration and Quarantine, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Amra Uzicanin
- Division of Global Migration and Quarantine, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Marcel Salathé
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
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18
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Baumann U, Knuf M. Impfungen zum Schutz vor Atemwegsinfektionen bei Risikogruppen. Monatsschr Kinderheilkd 2014. [DOI: 10.1007/s00112-013-3028-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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19
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Ahout I, Ferwerda G, de Groot R. Influenza vaccination in kids, are you kidding me? J Infect 2014; 68 Suppl 1:S100-7. [DOI: 10.1016/j.jinf.2013.09.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2013] [Indexed: 11/28/2022]
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20
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Influenza und Influenzaimpfstoffe für Kinder. Monatsschr Kinderheilkd 2013. [DOI: 10.1007/s00112-013-2940-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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21
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Bodewes R, Fraaij PLA, Osterhaus ADME, Rimmelzwaan GF. Pediatric influenza vaccination: understanding the T-cell response. Expert Rev Vaccines 2013; 11:963-71. [PMID: 23002977 DOI: 10.1586/erv.12.69] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Influenza A virus-specific T cells are highly cross-reactive and contribute to heterosubtypic immunity, which may afford protection against novel pandemic strains of influenza virus. However, the magnitude and nature of virus-specific T-cell responses induced by natural infections and/or vaccination in young children is poorly understood. Host factors, such as the development of the immune system during childhood and environmental factors such as exposure rates to influenza viruses and interference by vaccination contribute to shaping the magnitude and specificity of the T-cell response. Here, the authors review several of these factors, including the differences between T-cell responses of young children and adults, the age-dependent frequency of virus-specific T cells and the impact of annual childhood influenza vaccination. In addition, the authors summarize all currently available studies in which influenza vaccine-induced T-cell responses were evaluated. The authors discuss these findings in the light of developing vaccines and vaccination strategies aiming at the induction of protective immunity to seasonal and pandemic influenza viruses of antigenically distinct subtypes.
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Affiliation(s)
- Rogier Bodewes
- Department of Virology, Erasmus MC, Rotterdam, The Netherlands
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22
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Zhang F, Fang F, Chang H, Peng B, Wu J, Chen J, Wang H, Chen Z. Comparison of protection against H5N1 influenza virus in mouse offspring provided by maternal vaccination with HA DNA and inactivated vaccine. Arch Virol 2013; 158:1253-65. [DOI: 10.1007/s00705-013-1621-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 12/17/2012] [Indexed: 01/04/2023]
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23
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Zhang W, Moldovan I, Targoni OS, Subbramanian RA, Lehmann PV. How much of virus-specific CD8 T cell reactivity is detected with a peptide pool when compared to individual peptides? Viruses 2012. [PMID: 23202497 PMCID: PMC3509665 DOI: 10.3390/v4112636] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Immune monitoring of T cell responses increasingly relies on the use of peptide pools. Peptides, when restricted by the same HLA allele, and presented from within the same peptide pool, can compete for HLA binding sites. What impact such competition has on functional T cell stimulation, however, is not clear. Using a model peptide pool that is comprised of 32 well-defined viral epitopes from Cytomegalovirus, Epstein-Barr virus, and Influenza viruses (CEF peptide pool), we assessed peptide competition in PBMC from 42 human subjects. The magnitude of the peptide pool-elicited CD8 T cell responses was a mean 79% and a median 77% of the sum of the CD8 T cell responses elicited by the individual peptides. Therefore, while the effect of peptide competition was evident, it was of a relatively minor magnitude. By studying the dose-response curves for individual CEF peptides, we show that several of these peptides are present in the CEF-pool at concentrations that are orders of magnitude in excess of what is needed for the activation threshold of the CD8 T cells. The presence of such T cells with very high functional avidity for the viral antigens can explain why the effect of peptide competition is relatively minor within the CEF-pool.
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Affiliation(s)
- Wenji Zhang
- Cellular Technology Limited, Shaker Heights, Ohio 44122, USA.
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24
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Serological response to influenza A H1N1 vaccine (Pandemrix®) and seasonal influenza vaccine 2009/2010 in renal transplant recipients and in hemodialysis patients. Med Microbiol Immunol 2012; 201:297-302. [DOI: 10.1007/s00430-012-0231-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 01/27/2012] [Indexed: 12/25/2022]
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25
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Fraaij PLA, Bodewes R, Osterhaus ADME, Rimmelzwaan GF. The ins and outs of universal childhood influenza vaccination. Future Microbiol 2012; 6:1171-84. [PMID: 22004036 DOI: 10.2217/fmb.11.106] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Influenza viruses continue to cause disease of varying severity among humans. People with underlying disease and the elderly are at increased risk of developing severe disease after infection with an influenza virus. As effective and safe vaccines are available, the WHO has recommended vaccinating these groups against influenza annually. In addition to this recommendation, public health authorities of a number of countries have recently recommended vaccinating all healthy children aged 6-59 months against influenza. Here, we review the currently available data concerning the burden of disease in children, the economical impact of implementing universal vaccination of children, the efficacy of currently available influenza virus vaccines, the theoretical concerns regarding preventing immunity otherwise induced by infections with seasonal influenza viruses, and finally, how to address these concerns.
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Affiliation(s)
- Pieter L A Fraaij
- Department of Virology, Erasmus Medical Centre, PO Box 2040, 3000 CA Rotterdam, The Netherlands
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26
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Doerr HW, Cinatl J. Recent publications in medical microbiology and immunology: a retrospective. Med Microbiol Immunol 2011; 201:1-5. [PMID: 22033658 DOI: 10.1007/s00430-011-0219-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Indexed: 01/15/2023]
Abstract
A look back is done to some clinical and basic research activities recently published in medical microbiology and immunology. The review covers clinical experiences and in vitro experiments to understand the emergency, pathogenicity, epidemic spread, and vaccine-based prevention of avian and swine-origin flu. Some new developments and concepts in diagnosis, (molecular) epidemiology, and therapy of AIDS, viral hepatitis C, and herpesvirus-associated diseases are outlined. Regulation of immune system has been discussed in a special issue 2010 including some aspects of CNS affections (measles). Mycobacterial infection and its prevention by modern recombinant vaccines have reached new interest, as well as new concepts of vaccination and prophylaxis against several other bacteria. Adaptation to host niches enables immune escape (example brucella) and determines virulence (example N. meningitidis). Chlamydia pneumoniae, previously considered to trigger atherosclerosis, is hypothetically associated to Alzheimer disease, while CMV, another putative trigger of atherosclerosis, gains evidence of oncomodulation in CNS tumor diseases. In terms of globalization, exotic virus infections are increasingly imported from southern countries.
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Affiliation(s)
- H W Doerr
- Institute of Medical Virology, University Hospital of Frankfurt/M., Frankfurt/Main, Germany.
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Abstract
During the past decade, accumulating data on the impact of influenza virus-related disease in children have become available. In this review, we summarize and discuss these data. We conclude that mortality due to influenza in children is relatively limited. But, in contrast, influenza-related hospitalizations occur frequently. The bulk of the influenza-related disease burden is experienced in the outpatient setting. This results in sometimes very high consultation rates, frequent complications, and substantial parental work absenteeism.
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Smieszek T, Balmer M, Hattendorf J, Axhausen KW, Zinsstag J, Scholz RW. Reconstructing the 2003/2004 H3N2 influenza epidemic in Switzerland with a spatially explicit, individual-based model. BMC Infect Dis 2011; 11:115. [PMID: 21554680 PMCID: PMC3112096 DOI: 10.1186/1471-2334-11-115] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Accepted: 05/09/2011] [Indexed: 11/10/2022] Open
Abstract
UNLABELLED world has not faced a severe pandemic for decades, except the rather mild H1N1 one in 2009, pandemic influenza models are inherently hypothetical and validation is, thus, difficult. We aim at reconstructing a recent seasonal influenza epidemic that occurred in Switzerland and deem this to be a promising validation strategy for models of influenza spread. METHODS We present a spatially explicit, individual-based simulation model of influenza spread. The simulation model bases upon (i) simulated human travel data, (ii) data on human contact patterns and (iii) empirical knowledge on the epidemiology of influenza. For model validation we compare the simulation outcomes with empirical knowledge regarding (i) the shape of the epidemic curve, overall infection rate and reproduction number, (ii) age-dependent infection rates and time of infection, (iii) spatial patterns. RESULTS The simulation model is capable of reproducing the shape of the 2003/2004 H3N2 epidemic curve of Switzerland and generates an overall infection rate (14.9 percent) and reproduction numbers (between 1.2 and 1.3), which are realistic for seasonal influenza epidemics. Age and spatial patterns observed in empirical data are also reflected by the model: Highest infection rates are in children between 5 and 14 and the disease spreads along the main transport axes from west to east. CONCLUSIONS We show that finding evidence for the validity of simulation models of influenza spread by challenging them with seasonal influenza outbreak data is possible and promising. Simulation models for pandemic spread gain more credibility if they are able to reproduce seasonal influenza outbreaks. For more robust modelling of seasonal influenza, serological data complementing sentinel information would be beneficial.
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Affiliation(s)
- Timo Smieszek
- Institute for Environmental Decisions, Natural and Social Science Interface, ETH Zurich, Universitaetsstrasse 22, 8092 Zurich, Switzerland.
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Ortiz JR, Englund JA, Neuzil KM. Influenza vaccine for pregnant women in resource-constrained countries: a review of the evidence to inform policy decisions. Vaccine 2011; 29:4439-52. [PMID: 21550377 DOI: 10.1016/j.vaccine.2011.04.048] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Revised: 04/04/2011] [Accepted: 04/18/2011] [Indexed: 10/18/2022]
Abstract
Seasonal influenza is responsible for three to five million severe cases of disease annually, and up to 500,000 deaths worldwide. Pregnant women and infants suffer disproportionately from severe outcomes of influenza. The excellent safety profile and reliable immunogenicity of inactivated influenza vaccine support WHO recommendations that pregnant women be vaccinated to decrease complications of influenza disease during pregnancy. Nevertheless, influenza vaccine is not routinely used in most low-and middle-income countries and is not widely used in pregnant women worldwide. Two recent prospective, controlled trials of maternal influenza vaccination in Bangladesh and US Native American reservations demonstrated that inactivated influenza vaccine given to pregnant women can decrease laboratory-confirmed influenza virus infection in their newborn children. These studies support consideration of the feasibility of targeted influenza vaccine programs in resource-constrained countries. Platforms exist for the delivery of influenza vaccine to pregnant women worldwide. Even in the least developed countries, an estimated 70% of women receive antenatal care, providing an opportunity for targeted influenza vaccination. Challenges to the introduction of maternal influenza vaccination in resource-constrained countries exist, including issues regarding vaccine formulation, availability, and cost. Nonetheless, maternal influenza vaccination remains an important and potentially cost-effective approach to decrease influenza morbidity in two high-risk groups - pregnant women and young infants.
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Affiliation(s)
- Justin R Ortiz
- Vaccine Development Global Program, PATH, Seattle, WA, United States.
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Prevalence of antibodies against seasonal influenza A and B viruses in children in Netherlands. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2011; 18:469-76. [PMID: 21209157 DOI: 10.1128/cvi.00396-10] [Citation(s) in RCA: 136] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
To gain insight into the age at which children become infected with influenza viruses for the first time, we analyzed the seroprevalence of antibodies against influenza viruses in children 0 to 7 years of age in the Netherlands. Serum samples were collected during a cross-sectional population-based study in 2006 and 2007 and were tested for the presence of antibodies against influenza A/H1N1, A/H3N2, and B viruses representative of viruses present in previous influenza seasons using the hemagglutination inhibition assay. The seroprevalence of antibodies to influenza virus was higher in children 1 to 6 months of age than in children 7 to 12 months of age, which likely reflects the presence of maternally derived antibodies. The proportion of study subjects >1 year of age with detectable antibodies against influenza viruses gradually increased with age until they reached the age of 6 years, when they all had antibodies to at least one influenza A virus. These findings may have implications for the development of vaccination strategies aiming at the protection of young children against seasonal and/or pandemic influenza virus infection.
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Zhang R, Rong X, Pan W, Peng T. Determination of serum neutralization antibodies against seasonal influenza A strain H3N2 and the emerging strains 2009 H1N1 and avian H5N1. ACTA ACUST UNITED AC 2010; 43:216-20. [PMID: 21142624 DOI: 10.3109/00365548.2010.539258] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Humoral virus neutralizing activity is crucial in preventing influenza virus infection. However, the influenza neutralizing activity in the general population remains unclear. METHODS In this study we performed a serological survey of 200 blood donors from Guangzhou, China. Using a microneutralization (MN) assay, neutralizing activities against influenza A 2009 H1N1, H3N2 and H5N1 were measured. Anti-haemagglutinin antibody was assayed by haemagglutination inhibition (HI) test. Also, antibodies against M1 and M2 matrix proteins were measured using an enzyme-linked immunosorbent assay (ELISA). RESULTS By MN assay, 86% of the individuals showed neutralizing activity against H3N2, 11% against 2009 H1N1, and none against H5N1. The positive rate for H3N2 increased as the age of individuals increased. Interestingly, males displayed a 4 times higher positive rate against 2009 H1N1 than females. The results of ELISA revealed that 97.5% of the individuals had positive M1 titres and 21% had positive M2 titres. Furthermore, anti-haemagglutinin antibody had a much higher correlation with the neutralization activity than anti-M1 and anti-M2 antibodies. CONCLUSIONS Neutralizing activities against H5N1 and 2009 H1N1 were low in the general population. Therefore, public health agencies should design strategies for preventing potential H5N1 and 2009 H1N1 pandemics.
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Affiliation(s)
- Ruiqi Zhang
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
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Current knowledge on PB1-F2 of influenza A viruses. Med Microbiol Immunol 2010; 200:69-75. [DOI: 10.1007/s00430-010-0176-8] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Indexed: 10/18/2022]
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Comparison of pro-inflammatory cytokine expression and cellular signal transduction in human macrophages infected with different influenza A viruses. Med Microbiol Immunol 2010; 200:53-60. [DOI: 10.1007/s00430-010-0173-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Indexed: 12/20/2022]
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Allwinn R, Geiler J, Berger A, Cinatl J, Doerr HW. Determination of serum antibodies against swine-origin influenza A virus H1N1/09 by immunofluorescence, haemagglutination inhibition, and by neutralization tests: how is the prevalence rate of protecting antibodies in humans? Med Microbiol Immunol 2010; 199:117-21. [PMID: 20162304 DOI: 10.1007/s00430-010-0143-4] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Indexed: 11/27/2022]
Abstract
In April 2009, a new variant of influenza A virus, subtype H1N1v emerged in Mexico and spread all over the world producing the H1N1 pandemic in mankind after 1918-1920 and 1978/1979. Obviously there was no herd immunity against this new virus variant. Mainly young people, but less elderly were affected and presented severe and even lethal courses of disease. Since virus-specific antibodies are commonly regarded as markers of partial or complete immunoprotection, we performed antibody determinations in serum samples obtained from people before and after the pandemic has arrived in our region (Frankfurt/M., Germany). The assays were done by indirect immunofluorescence, by neutralization test, and by a haemagglutination inhibition test (HI), which was established in a practical modification for general and easy use. Among 145 individuals, of whom serum specimens had been drawn before the onset of pandemic, 19 revealed humoral immunity, i.e. titres of H1N1v neutralizing antibodies (at least 1:64). Eleven were older than 60 years, one belonged to the age group 40-59 years, three to the age group 20-39 years, and two to the age group 15-19 years. After the onset of pandemic in Frankfurt, serum specimens drawn from n = 225 randomly selected patients of our local university hospital were investigated for antibodies against H1N1v by HI, which is generally recommended for routine check of immunity. Twenty-eight individuals revealed the protecting antibody titre of at least 1:40. The age distribution had moved to mean age groups. The results fit to the incidence of influenza A/H1N1(09) disease, as confirmed by RT-PCR in patients admitted to our hospital, peaking in the younger age groups up to 30 years (second affected group: 30-40 years). While commonly used solid-phase antibody tests (like immunofluorescence) are not suitable to diagnose passed H1N1(09) infection and acquired immunity, this can be easily done by HI. Expecting the next waves of influenza A/H1N1v infections, HI testing may avoid vaccinations under special risk of severe or hidden adverse reactions.
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Affiliation(s)
- Regina Allwinn
- Institute of Medical Virology, University Hospital, Frankfurt/M., Germany
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Bodewes R, Kreijtz JHCM, Rimmelzwaan GF. Yearly influenza vaccinations: a double-edged sword? THE LANCET. INFECTIOUS DISEASES 2009; 9:784-8. [PMID: 19879807 DOI: 10.1016/s1473-3099(09)70263-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Yearly vaccination against seasonal influenza viruses is recommended for certain individuals at high risk of complications associated with influenza. It has been recommended in some countries, including the USA, that all children aged 6-59 months are vaccinated against seasonal influenza. However, it has been shown-mainly in animals-that infection with influenza A viruses can induce protective immunity to influenza A viruses of other unrelated subtypes. This so-called heterosubtypic immunity does not provide full protection, but can limit virus replication and reduce morbidity and mortality of the host. This type of immunity might be relevant to human beings when a new subtype of influenza A virus is introduced into the population, such as the new influenza A H1N1 virus responsible for the present influenza pandemic and the highly pathogenic avian influenza H5N1 viruses that are causing an ever increasing number of human infections with high mortality rates. Preventing infection with seasonal influenza viruses by vaccination might prevent the induction of heterosubtypic immunity to pandemic strains, which might be a disadvantage to immunologically naive people-eg, infants.
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Affiliation(s)
- Rogier Bodewes
- Department of Virology, Erasmus Medical Center, Rotterdam, The Netherlands
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