Watch the Pigs

Sampling for potentially pandemic strains of influenza virus at hog farms is lax compared with poultry farms, worrying some experts.

Jun 25, 2012
Edyta Zielinska


Influenza from people, poultry, camels and even whales is regularly monitored and sent to epidemiologists who track the latest permutations in the virus. Despite the fact that the 2009 influenza strain called swine flu spent years evolving in North American pig farms, very little data is collected on this species, reported Wired Science.

Although swine flu may have jumped to another species, such as chicken, before infecting humans, the lack of information on the viral evolution that took place in pigs first has made it difficult to understand which components of the virus made it so virulent.

Some pork farms do report data, although independent testing is rare. The largest world producer of pork, Smithfield Farms conducts flu tests on its herd, and reported no virus in 2009, despite being near the outbreak’s epicenter, according to Wired Science. While reporting has increased since 2009, large gaps remain, in part because the virus doesn’t usually kill pigs and threaten the farms. In contrast, many people inaccurately assume that swine flu can be contracted by eating pork products—a belief that can hurt the industry, making farmers less comfortable with reporting the infections. The current compromise is to keep data from pig farms anonymous so that only the state is listed as a location, although researchers say this can limit the data’s value.