Estimating influenza outpatients' and inpatients' incidences from 2009 to 2011 in a tropical urban setting in the Philippines

Influenza and Other Respiratory Viruses

Veronica L. Tallo¹  Taro Kamigaki⁴  Alvin G. Tan¹  Rochelle R. Pamaran³  Portia P. Alday¹  Edelwisa S. Mercado²  Jenaline B. Javier¹  Hitoshi Oshitani⁴ 

[1] Department of Epidemiology and Biostatistics, Research Institute for Tropical Medicine, Department of Health, Manila, Philippines;Molecular Biology Laboratory, Research Institute for Tropical Medicine, Department of Health, Manila, Philippines;Research Institute for Tropical Medicine, Department of Health, Manila, Philippines;Department of Virology, Tohoku University Graduate School of Medicine, Sendai, Japan

关键词: Disease burden;    influenza;    influenza‐like illness;    Philippines;    severe acute respiratory infection;   

DOI  :  10.1111/irv.12223

来源: Wiley

【 摘 要 】

Abstract

Objectives

Although the public health significance of influenza in regions with a temperate climate has been widely recognized, information on influenza burden in tropical countries, including the Philippines, remains limited. We aimed to estimate influenza incidence rates for both outpatients and inpatients then characterized their demographic features.

Design

An enhanced surveillance was performed from January 2009 to December 2011 in an urbanized highland city. The influenza-like illness (ILI) surveillance involved all city health centers and an outpatient department of a tertiary government hospital. The severe acute respiratory infection (sARI) surveillance was also conducted with one government and four private hospitals since April 2009. Nasal and/or oropharyngeal swabs were collected and tested for influenza A, influenza B, and respiratory syncytial virus.

Results and Conclusions

We obtained 5915 specimens from 13 002 ILI cases and 2656 specimens from 10 726 sARI cases throughout the study period. We observed year-round influenza activity with two possible peaks each year. The overall influenza detection rate was 23% in the ILI surveillance and 9% in the sARI surveillance. The mean annual outpatient incidence rate of influenza was 5·4 per 1000 individuals [95% confidence interval (CI), 1·83–12·7], and the mean annual incidence of influenza-associated sARI was 1·0 per 1000 individuals (95% CI, 0·03–5·57). The highest incidence rates were observed among children aged <5 years, particularly those aged 6–23 months. Influenza posed a certain disease burden among inpatients and outpatients, particularly children aged <5 years, in an urbanized tropical city of the Philippines.

【 授权许可】

CC BY   
© 2014 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.