The Epidemic Human Adenovirus And Molecular Characterization In Seven Provinces And Cities Of China Mainland,2010-2012

Human adenoviruses are non-enveloped, dsDNA viruses and belong to the genus of Mastadenovirus of the family of Adenoviridae. Based on the traditional serum neutralization test,52HAdV serotypes are grouped into7species (A-G). Along with the progress of molecular biological technique and bioinformatics analysis,14new types of HAdVs (HAdV-53-67) were detected by the whole genome sequeing and bioinformatics analysis from2007. However, it is not clear that the mechanism of the new types of HAdV formation, most of them were recombination from two or more serotypes in the same subgenus. Whether the traditional serotypes or the new types of HAdV, both of them were closely related to many human diseases, such as respiratory infections, conjunctivitis, gastroenteritis. HAdV infection is common in China. Adenovirus pneumonia is one of the most common viral pneumonias and HAdVs are the pathogen caused epidemic keratoconjunctivitis. There are no large epidemics of HAdV in China in recent years, but outbreaks were occurred in some districts. Nowadays, except for Amercia and Japan, no country has routine monitoring for HAdVs. HAdV can cause theworld-wide infectious diseases, so it is important to bulit a surveillance to explore the epidemiological characteristics, prevent and control the outbreak and popularity of HAdVs.Based on the China Mega Project for Infectious Disease, throat swabs were collected from febrile respiratory syndrome project in Gansu, Shanxi, Jiangxi, Hebei provinces and Shanghai, Beijing cities between2010and2012and clinical samples from two epidemic situations caused by two new types of HAdVs. Then multiple RT-PCR was used to screen the HAdVs and virus isolation, PCR for HVR of hexon gene and sequencing were performed to identify the type of HAdVs and analyze genetic characteristics. The results were as follows:(1)79HAdV-positive samples were collected from six provinces and cities between2010and2012. HAdV-3was the predominant serotype, HAdV-7came second. The evolution of HAdV-3、7、1、2、5circulated in six provinces of China was slow and no apparent genetic variation occurred.(2) HAdV-14p1was confirmed as the pathogen for the ILI epidemic situation in Tongwei county of Gansu province. This is the first identification of HAdV-14p1as the pathogen caused outbreak of respiratory infection in China; also the first outbreak caused by.HAdV-14p1occurred in adolescents in the world. HAdV-56firstly caused the outbreak of EKC in Dalian city of Liaoning province, the incubation of HAdV-56caused EKC was10-15days. Intimate contact and closed room were the factors make viruses spread quickly. Isolating sourse of infection and cutting off transmission route can contol the epidemic situation effectively.Through the above study, we preliminary understand the serotype distribution and genetic characteristics of HAdVs circulated in six provinces and cities in China; and expound the epidemiological, clinical and viral characteristics of two new types of HAdVs:HAdV-14p1and HAdV-56in the outbreaks. It provides scientific basis to bulit the laboratory surveillance for HAdVs in China.