Viral etiology of 363 elderly people with influenza-like illness and severe acute respiratory infections in Pudong New Area, Shanghai / 上海预防医学

ABSTRACT

Objective To understand the epidemiological characteristics of common respiratory viruses among influenza-like illness (ILI) and severe acute respiratory infections (SARI) in Pudong New Area, Shanghai , so as to help estimate the disease burden and conduct the valuable control strategies . Methods Respiratory specimen ( throat swab or sputum ) from cases older than 65 years old with ILI/SARI were collected from outpatient and inpatient settings in four sentinel hospitals in Pudong New Area . Each specimen was tested by multiplex PCR for eight target viral etiologies , including influenza virus , human rhinoviruses ( HRV ) , human para-influenza virus ( PIV ) , adenoviruses ( ADV ) , respiratory syncytial virus ( RSV ) , human metapneumovirus ( hMPV ) , human coronavirus ( hCoV ) and human bocavirus ( hBoV) .Chi-square tests or Fisher's Exact Test were used to compare and analyze . Results From January 1st, 2014 to June 30st, 2016, a total of 363 elderly cases with ILI/SARI were enrolled, with 202 (55.65%) male and a median age of 70 years old.142(39.12%) patients were detected posi-tive for any one of the eight viruses.Influenza was the predominant virus (20.94%, 76/363), with the positive proportion of ( 29 .83%) among ILI cases and ( 12 .09%) among SARI cases .The Influenza infection presented two seasonal peaks in winter ( December to February ) and summer ( July to September ) . Conclusion Influenza is identified as the leading viral pathogen both among ILI and SARI cases older than 65 years old, and two seasonal epidemic peaks areobserved in Shanghai .Influenza vacci-nation strategy should be advocated for the elderly population in Shanghai .