tetano
Editor, Senior Moderator
Am J Epidemiol. 2015 Sep 22. pii: kwv110. [Epub ahead of print]
[h=1]Comparative Epidemiology of Influenza B Yamagata- and Victoria-Lineage Viruses in Households.[/h] Xu C, Chan KH, Tsang TK, Fang VJ, Fung RO, Ip DK, Cauchemez S, Leung GM, Peiris JS, Cowling BJ.
[h=3]Abstract[/h] Influenza B viruses split into 2 distinct lineages in the early 1980s, commonly named the Victoria and Yamagata lineages. There are few data on the comparative epidemiology of Victoria- and Yamagata-lineage viruses. In 2007-2011, we enrolled 75 and 34 households containing index patients with acute respiratory illness who tested positive for Yamagata- and Victoria-lineage viruses, respectively, from outpatient clinics in Hong Kong, China. These index patients and their household contacts were followed up for 7-10 days. We examined overall risk of polymerase chain reaction-confirmed infection among household contacts and the risk of secondary infection within households using an individual-based hazard model that accounted for tertiary transmission and infections occurring outside the household. We found that for Victoria-lineage viruses, the risk of within-household infection among household contacts aged ≤15 years was significantly higher (risk ratio = 12.9, 95% credibility interval: 4.2, 43.6) than that for older household contacts, while for Yamagata-lineage viruses, the risk of within-household infection for household contacts did not differ by age. Influenza B Yamagata- and Victoria-lineage viruses have similar characteristics in terms of viral shedding and clinical illness. The mechanisms underlying these epidemiologic differences deserve further investigation.
? The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
[h=4]KEYWORDS:[/h] Victoria lineage; Yamagata lineage; disease transmission; influenza; influenza B virus
PMID: 26400854 [PubMed - as supplied by publisher]
[h=1]Comparative Epidemiology of Influenza B Yamagata- and Victoria-Lineage Viruses in Households.[/h] Xu C, Chan KH, Tsang TK, Fang VJ, Fung RO, Ip DK, Cauchemez S, Leung GM, Peiris JS, Cowling BJ.
[h=3]Abstract[/h] Influenza B viruses split into 2 distinct lineages in the early 1980s, commonly named the Victoria and Yamagata lineages. There are few data on the comparative epidemiology of Victoria- and Yamagata-lineage viruses. In 2007-2011, we enrolled 75 and 34 households containing index patients with acute respiratory illness who tested positive for Yamagata- and Victoria-lineage viruses, respectively, from outpatient clinics in Hong Kong, China. These index patients and their household contacts were followed up for 7-10 days. We examined overall risk of polymerase chain reaction-confirmed infection among household contacts and the risk of secondary infection within households using an individual-based hazard model that accounted for tertiary transmission and infections occurring outside the household. We found that for Victoria-lineage viruses, the risk of within-household infection among household contacts aged ≤15 years was significantly higher (risk ratio = 12.9, 95% credibility interval: 4.2, 43.6) than that for older household contacts, while for Yamagata-lineage viruses, the risk of within-household infection for household contacts did not differ by age. Influenza B Yamagata- and Victoria-lineage viruses have similar characteristics in terms of viral shedding and clinical illness. The mechanisms underlying these epidemiologic differences deserve further investigation.
? The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
[h=4]KEYWORDS:[/h] Victoria lineage; Yamagata lineage; disease transmission; influenza; influenza B virus
PMID: 26400854 [PubMed - as supplied by publisher]