RESUMO
Natural infections with influenza A viruses have been reported in a variety of animal species including humans, pigs, horses, sea mammals, and birds. Although viruses of relatively few haemagglutinin(HA) and neuraminidase(NA) subtype combinations have been isolated from mammalian species, all subtypes, in most combinations, have been isolated from birds. During the past few years, several subtypes of avian influenza A have been shown to cross the species barrier and infect humans. During an outbreak of a highly pathogenic influenza A(H5N1) virus among poultry in Hong Kong in 1997, 6 of 18 people with confirmed infection died. And a total of 89 human infections with influenza A(H7N7), including 1 resulting in the death of a Dutch veterinarian, occurred during the extensive outbreak in 2003. During late 2003 and early 2004, there were reports of large outbreaks of H5N1 among poultry throughout Asia (including Korea, Japan, Indonesia, Vietnam, Thailand, Laos, Cambodia, and China). In Korea, we had also highly pathogenic avian influenza(HPAI) outbreak in 2003~2004 with a first suspected case reported on 10 December 2003. The case was reported at a parent stock farm for broilers, which was located in Chungbuk province, and the farm was immediately placed under movement restrictions. Laboratory tests confirmed the outbreak of HPAI on 12 December 2003. Up to 20 March 2004, a total of 19 farms were confirmed as having been infected with HPAI virus. No further outbreaks occurred after that date. Fortunately there were no human cases founded in this epidemic in Korea. In January 2004, there was confirmation that influenza A(H5N1) virus had been isolated from patients who had died of a respiratory illness in Vietnam. Total 107 human confirmed cases were reported until June 2005 to WHO, threatening new pandemic outbreak. We reviewed our prevention and control strategies of avian influenza and preparedness to the pandemic outbreak.
