‘There is too little genetic surveillance of last year’s human pandemic flu, which has gone on to infect pigs in China and is readily mixing with other flus there, according to a study released Thursday by researchers in Hong Kong. . . .

‘In the new study, published online in the journal Science, the Hong Kong researchers sequenced viruses they found by regularly swabbing pigs’ snouts at the territory’s largest slaughterhouse, which gets pigs from all over southern China. That testing, supported by a United States government grant, has gone on for 12 years.

‘“The message from our paper is not an inevitable disaster around the corner, but the need for continued vigilance,” Malik Peiris, a flu expert at the University of Hong Kong and one of the study’s authors, said in an e-mail message.

‘Among the globe-circulating flus that pigs could, in theory, catch are six swine flus, several human seasonal ones and at least two avian ones. The latter include the feared H5N1, which has killed 60 percent of the 500 people known to have caught it since 2003 but thus far almost never spreads from person to person, and an H9N2, which has been found in about a dozen humans but caused only mild disease so far.

‘Last year’s pandemic was originally dubbed a “swine flu” because the eight genes in its makeup had been seen before in American or Eurasian pigs during the previous 10 years, though never in the exact combination that was making people sick in Mexico.’Study published in Science criticizes swine-flu follow-up

More . . . (New York Times, 17 June 2010)