Viral spectrum of 36 outbreaks of influenza like-illness in Shandong province / 中华实验和临床病毒学杂志

ABSTRACT

Objective@#To understand the viral spectrum of influenza-like illness (ILI), Shandong province during 2013-2014.@*Methods@#The data of 36 ILI outbreaks were collected and analyzed. Multiple respiratory pathogens were detected with RT-PCR in pharynx swab specimens.@*Results@#Totally, 35 outbreaks occurred in winter and spring, and dispersed in 12 cities; 27 outbreaks happened in primary and secondary schools. Many of the outbreaks, 17 (47.2%), were caused by influenza virus type B (FluB), followed by FluA H1 and H3, 5 (13.8%) outbreaks, respectively. Mixed infection caused 7 outbreaks. Totally 437 samples were collected, with 235 (53.8%) positive specimens, in which FluB was mostly detected, 142 (32.5%). Except Flu, parainfluenza virus type 2 (PIV2) was the most frequently detected, followed by coronavirus (CoV). The constituent ratio of FluB under 15 years of age was the highest, such as CoV in 25-59 years old group and FluA H1 in others groups.@*Conclusions@#ILI outbreaks occurred mostly in primary and secondary schools. Virus was the main pathogen, with the dominant strains of FluB. However, the dominant strain in different age groups was different.