{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T15:43:29Z","timestamp":1791387809016,"version":"4.3.3"},"reference-count":44,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,9,21]],"date-time":"2022-09-21T00:00:00Z","timestamp":1663718400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research Fund for the Control of Infectious Diseases of the Health, Welfare and Food Bureau of the Hong Kong SAR Government","award":["CHP-CE-03"],"award-info":[{"award-number":["CHP-CE-03"]}]},{"name":"Research Fund for the Control of Infectious Diseases of the Health, Welfare and Food Bureau of the Hong Kong SAR Government","award":["T11-712\/19N"],"award-info":[{"award-number":["T11-712\/19N"]}]},{"name":"Research Fund for the Control of Infectious Diseases of the Health, Welfare and Food Bureau of the Hong Kong SAR Government","award":["05190097"],"award-info":[{"award-number":["05190097"]}]},{"name":"Theme-based Research Scheme","award":["CHP-CE-03"],"award-info":[{"award-number":["CHP-CE-03"]}]},{"name":"Theme-based Research Scheme","award":["T11-712\/19N"],"award-info":[{"award-number":["T11-712\/19N"]}]},{"name":"Theme-based Research Scheme","award":["05190097"],"award-info":[{"award-number":["05190097"]}]},{"name":"Health and Medical Research Fund, Food and Health Bureau, Government of the Hong Kong Special Administrative Region","award":["CHP-CE-03"],"award-info":[{"award-number":["CHP-CE-03"]}]},{"name":"Health and Medical Research Fund, Food and Health Bureau, Government of the Hong Kong Special Administrative Region","award":["T11-712\/19N"],"award-info":[{"award-number":["T11-712\/19N"]}]},{"name":"Health and Medical Research Fund, Food and Health Bureau, Government of the Hong Kong Special Administrative Region","award":["05190097"],"award-info":[{"award-number":["05190097"]}]},{"name":"Laboratory of Excellence Integrative Biology of Emerging Infectious Diseases","award":["CHP-CE-03"],"award-info":[{"award-number":["CHP-CE-03"]}]},{"name":"Laboratory of Excellence Integrative Biology of Emerging Infectious Diseases","award":["T11-712\/19N"],"award-info":[{"award-number":["T11-712\/19N"]}]},{"name":"Laboratory of Excellence Integrative Biology of Emerging Infectious Diseases","award":["05190097"],"award-info":[{"award-number":["05190097"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Influenza vaccination is an important intervention to prevent influenza virus infection. Our previous analysis suggested that indirect protection is limited in an influenza B epidemic in Hong Kong. We further analyzed six influenza A epidemics to determine such potential. We applied a statistical model to estimate household transmission dynamics in the 3 influenza A(H3N2) and 3 pandemic influenza A(H1N1) epidemics. Then, we estimated the reduction in infection risk among unvaccinated household members when all children in households are vaccinated, with different assumptions on vaccine efficacy (VE). In the optimal scenario that VE was 70%, the reduction to the total probability of infection was only marginal, with relative probabilities ranged from 0.91\u20130.94 when all children in households were vaccinated because community was by far the main source of infection during the six epidemics in our study. The proportion of cases attributed to household transmission was 10% (95% CrI: 7%, 13%). Individual influenza vaccination is important even when other household members are vaccinated, given the degree of indirect protection is small.<\/jats:p>","DOI":"10.3390\/v14102097","type":"journal-article","created":{"date-parts":[[2022,9,23]],"date-time":"2022-09-23T04:07:07Z","timestamp":1663906027000},"page":"2097","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Indirect Protection from Vaccinating Children against Influenza A Virus Infection in Households"],"prefix":"10.3390","volume":"14","author":[{"given":"Tim K.","family":"Tsang","sequence":"first","affiliation":[{"name":"WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China"},{"name":"Laboratory of Data Discovery for Health Limited, Hong Kong Science and Technology Park, New Territories, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Can","family":"Wang","sequence":"additional","affiliation":[{"name":"WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vicky J.","family":"Fang","sequence":"additional","affiliation":[{"name":"WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ranawaka A. P. M.","family":"Perera","sequence":"additional","affiliation":[{"name":"WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China"},{"name":"HKU-Pasteur Research Pole, The University of Hong Kong, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hau Chi","family":"So","sequence":"additional","affiliation":[{"name":"WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dennis K. M.","family":"Ip","sequence":"additional","affiliation":[{"name":"WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8217-5995","authenticated-orcid":false,"given":"J. S. Malik","family":"Peiris","sequence":"additional","affiliation":[{"name":"WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China"},{"name":"HKU-Pasteur Research Pole, The University of Hong Kong, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriel M.","family":"Leung","sequence":"additional","affiliation":[{"name":"WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China"},{"name":"Laboratory of Data Discovery for Health Limited, Hong Kong Science and Technology Park, New Territories, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simon","family":"Cauchemez","sequence":"additional","affiliation":[{"name":"Mathematical Modelling of Infectious Diseases Unit, Institut Pasteur, UMR2000, CNRS, 75015 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin J.","family":"Cowling","sequence":"additional","affiliation":[{"name":"WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China"},{"name":"Laboratory of Data Discovery for Health Limited, Hong Kong Science and Technology Park, New Territories, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1285","DOI":"10.1016\/S0140-6736(17)33293-2","article-title":"Estimates of global seasonal influenza-associated respiratory mortality: A modelling study","volume":"391","author":"Iuliano","year":"2018","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"687","DOI":"10.1016\/S1473-3099(12)70121-4","article-title":"Estimated global mortality associated with the first 12 months of 2009 pandemic influenza A H1N1 virus circulation: A modelling study","volume":"12","author":"Dawood","year":"2012","journal-title":"Lancet Infect. 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