Pandemic (H1N1) 2009 Virus Circulating in Pigs, Guangxi, China

摘要

To the Editor: A novel swine-originated in. uenza A virus known as pandemic (H1N1) 2009 was fi rst isolated from humans in Mexico in April 2009 (1), and a worldwide pandemic followed, which affected >214 countries and resulted in >18,000 deaths (2). In August 2010, the World Health Organization stated that the pandemic caused by this virus had ended. As this virus emerged, animals, including swine, turkeys, ferrets, cats, and cheetahs, were found to have been infected (3). In addition, transmission from humans to pigs in porcine herds has been reported (4).Swine in. uenza A virus (SIV) belongs to the family Orthomyxoviridae and is a causative agent of respiratory disease in pigs (5). Currently, 3 subtypes of in. uenza viruses are circulating in the swine population globally: H1N1, H3N2, and H1N2 (6,7). Pigs can be simultaneously infected with avian in. uenza viruses and human in. uenza viruses, and the viruses can exchange genes and produce new variants, which suggests that pigs have become mixing vessels for in. uenza viruses (8). Pandemic (H1N1) 2009, caused by a virus usually circulating in pigs in Europe and Asia, is a triple hybrid that contains swine, human, and avian virus gene segments, which further emphasizes that SIVs pose a serious threat to public health. We describe an outbreak of pandemic (H1N1) 2009 virus, which was isolated from a pig farm in Guangxi Province, People's Republic of China, and report the consequences of subsequent epidemiologic studies