The June 18 issue of Science reports that by monitoring the swine at a Hong Kong slaughterhouse, researchers have found that the pandemic H1N1 influenza virus from 2009 has been reorganizing its genes in pigs for the past year and a half.

This discovery concerns the researchers because further genetic "reassortment" could eventually give rise to another that is harmful to humans.

For this reason, Dhanasekaran Vijaykrishna and colleagues argue that global surveillance of swine should be heightened.

In a Brevium, these researchers describe how they identified a novel genetic reassortment of the H1N1 virus in January of this year and analyzed it to confirm that it arose from the H1N1/2009 virus.

They suggest that the introduction of the H1N1/2009 virus back into swine allowed it to reorganize its genes, and they warn that this 2010 virus could undergo further reassortment in swine and become dangerous to humans.

Vijaykrishna and colleagues call for a complete characterization of the eight H1 influenza genes identified in the new strain so that future reassortment events can be quickly recognized and identified.

More information: "Reassortment of Pandemic H1N1/2009 Influenza A Virus in Swine," by D. Vijaykrishna; L.L.M. Poon; H.C. Zhu; S.K. Ma; O.T.W. Li; C.L. Cheung; G.J.D. Smith; J.S. M. Peiris; Y. Guan at University of Hong Kong in Hong Kong, China; D. Vijaykrishna; H.C. Zhu; G.J.D. Smith; Y. Guan at Shantou University Medical College in Shantou, China; D. Vijaykrishna at Duke-NUS Graduate Medical School in Singapore, Singapore.

Provided by AAAS