Scientists discover multiple avian influenza strains in Chinese swine

Scientists recently reported on the seroprevalence of strains of avian influenza viruses found in pigs kept in southern China.

The analyzed viruses do not include the H5N1 strain. The researchers believe their study could have major public health implications in efforts to limit the potential damage caused by a pandemic in humans, according to

Swine can be infected by both human and avian influenza viruses, and are therefore believed to be important sources of the kind of genetic reassortment that can result in a pandemic. Pigs have been infected by all of the avian influenza subtypes, H1-H13, but the natural transmission of avian influenza into pigs has only been observed in rare instances.

The new study, which will be published in the February issue of the Journal of Clinical Microbiology, was conducted from 2010-2012 by Guihong Zhang and his colleagues from the South China Agricultural University College of Veterinary Medicine in Guangzhou. The researchers tested more than 1,000 pigs for four subtypes of avian influenza and two subtypes of swine influenza A.

While none of the viruses were found in swine in similar testing conducted in 2001, they were found during the recent study. The recent transmission of avian influenza into swine raised alarms for Zhang and his colleagues.

"We recommend strongly that the pork industry worldwide should monitor the prevalence of influenza in pigs, considering their important role in transmitting this virus to humans," Zhang said, reports.