By Lucy Hornby, Reuters
BEIJING — China is not the source of blue ear disease outbreaks among pigs in Vietnam and Myanmar, Ministry of Agriculture officials said Monday, adding that the disease in China closely resembles that found in the United States. Blue ear disease, formally known as Porcine Reproductive and Respiratory Syndrome, has infected 290,000 pigs in China so far this year at latest count, vice minister of agriculture Gao Hongbin told a news conference. That’s up from 257,000 that had been infected by late August, according to a toll released by state media. “We got the disease from abroad and there is no evidence to show it spread from China to anywhere else,” Gao said. Blue ear disease was first recognized in the United States in the mid-1980s and has since turned up in most pork-producing nations. “In 1996, China first got the blue ear virus. Analysis of the disease this year shows it is 93 percent the same as the U.S. type,” added Li Jinxiang, deputy director general of the ministry’s veterinary bureau. “So China is a victim. The allegation that the disease spread from China to Vietnam and Myanmar is groundless.” A widespread outbreak that began in China in May last year killed about 1 million pigs in 2006, unusually affecting adult pigs with high fever. It was subsequently identified as highly pathogenic PRRS, and has not affected humans. Vietnam reported this month that blue ear disease had again broken out in Khanh Hoa and Ca Mau provinces, after declaring it eradicated in August. A June outbreak in the central region infected 60,000 pigs. “A delegation from Vietnam to China mentioned that they had this disease, but the OIE Web site has had no report,” Li said, referring to the world animal health body in Paris. “As for Myanmar, we have had no confirmed proof.” Epidemiologists are particularly concerned about possible mutations of disease in southern China, where humans, pigs and chickens live in close proximity in hot, humid weather. Separately, the officials said China had received no new international requests for bird flu samples, after it last provided samples in June following a year-long hiatus. “The Ministry of Agriculture hasn’t received any requests from any international organizations or laboratories,” Li said, adding that China had provided the World Health Organization genome results that related to human outbreaks. “If they feel they need more, then we will cooperate in giving it to them based on our agreements.” Scientists say that sharing samples of viruses, which are constantly changing, is vital to see if they have developed resistance to drugs or become more easily transmissible.
Genetic analysis of the virus is also essential for developing commercial vaccines and diagnostic tests, the WHO says. The H5N1 virus remains mainly a virus of birds, but experts fear it could change into a form easily spread from person to person and sweep around the world, sparking a pandemic which could kill millions within months. Altogether, China has provided 23 bird-flu-related samples, Li said. “Since viruses are all infectious, even if there was a request we would need national government approval to send it overseas.”