To understand an adenovirus outbreak in Fenghua by epidemiological investigation and laboratory detection, so as to provide basis for taking effective control measures timely.

The adenovirus outbreak in a swimming pool in Fenghua in 2016 was investigated to analyze the course of disease and epidemiological characteristics. The throat swab samples were collected and detected by real-time PCR. The positive adenovirus specimens were further isolated. The hexon regions were amplified and sequenced. All the sequences were compared based on BLAST in GenBank, and cladogram of adenovirus hexon gene was constructed by MEGA5.2 to identify the exact adenovirus type.

The epidemic lasted 15 days with a total of 18 hospitalized cases whose main clinical symptoms were fever, suppurative tonsillitis and bloodshot eyes. All the cases exposed to the same swimming pool within 1-5 days before the onset. Ten throat swab samples were respiratory adenovirus positive by PCR with a CT value of 17-26. BLAST analysis on hexon gene showed that the 6 adenovirus isolates had the same sequence. The phylogenetic tree revealed that these isolates were all adenovirus B subsets, which were homologous to those of human adenovirus type 3 with 99.1%-99.8% similarity.

This outbreak of acute respiratory tract infections is caused by human adenovirus type 3.

Adenoviruses, human; Epidemiology; Genotype