Advanced search
Start date
Betweenand
Related content
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Influenza virus prevalence in asymptomatic and symptomatic subjects during pandemic and postpandemic periods

Full text
Author(s):
Melchior, Thais Boim [1] ; Perosa, Ana Helena [1] ; Camargo, Clarice Neves [1] ; Granato, Celso [1] ; Bellei, Nancy [1]
Total Authors: 5
Affiliation:
[1] Univ Fed Sao Paulo, Dept Med, Clin Virol Lab, Infect Dis Unit, Sao Paulo, SP - Brazil
Total Affiliations: 1
Document type: Journal article
Source: AMERICAN JOURNAL OF INFECTION CONTROL; v. 43, n. 5, p. 460-464, MAY 1 2015.
Web of Science Citations: 2
Abstract

Background: In 2009, Influenza A(H1N1) pdm09 had a major effect on global health, causing thousands of deaths. However, the results of asymptomatic infection in transmission has not been well studied. We analyzed asymptomatic influenza infection in individuals with different risk factors for acquiring influenza in a university hospital. Methods: Respiratory samples from 100 children with respiratory symptoms, their asymptomatic care-givers, 100 asymptomatic HIV-infected patients, and 100 health care workers collected during 2009-2011 were tested for influenza by real time real-time polymerase chain reaction. Results: Influenza infection rate in symptomatic children was 44% and in asymptomatic adults it was 8.3% (P < .01). Children older than age 5 years had a 3.4 times greater chance of being infected during influenza season than younger children. Among the asymptomatic group, influenza was more frequent in caregivers (14%; P = .032) and a higher rate (31.8%) was observed if a child was infected during the 2009 pandemic. Contact with an infected child was an important risk factor for influenza acquisition (odds ratio, 3.8; 95% confidence interval, 1.1-13.2) among caregivers. The mean cluster of differentiation 4 T-cell count of HIV-positive patients infected with influenza was not statistically different from uninfected patients (P = .29). Conclusions: Asymptomatic household contacts of symptomatic children may play an important role in community transmission and a more proactive intervention should be considered during future pandemics. Copyright (C) 2015 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved. (AU)

FAPESP's process: 10/09272-5 - Pandemic Influenza A H1N1 investigation in asymptomatic patients and health care workers
Grantee:Nancy Cristina Junqueira Bellei
Support Opportunities: Regular Research Grants