There have been a few exceptions to the restrained coverage in mainstream news outlets (mostly among British publications, curiously enough). The Times of London and The Independent ran articles that themselves were not substantially different from others. Their respective headlines, however—“Mexico outbreak traced to ‘manure lagoons’ at pig farm” and “For La Gloria, the stench of blame is from pig factories”—were sensationalistic and grossly misleading.

The Guardian has run two op-eds on the subject. One, by a University of California history professor, made the rash statement in its lede that, “The Mexican swine flu, a genetic chimera probably conceived in the faecal mire of an industrial pigsty, suddenly threatens to give the whole world a fever.” The other, by a member of the European Parliament, called for more research and quoted the director of Public Health and Animal Agriculture at the U.S. Humane Society saying that the first triple-hybrid swine flu virus (as the one responsible for the current outbreak appears to be) emerged at a North Carolina factory farm in 1998.

Clearly, it is too early to make bold pronouncements about CAFOs’ role in abetting the epidemic that has now spread to seven countries. As a front-page article in The New York Times on Wednesday pointed out, even “La Gloria may not, in the end, be the source of anything.” And Yulsman, who originally chided the press for ignoring factory farms, wrote a follow-up post criticizing CNN’s Headline News for hyping the threat they pose. Many worry that jumping to conclusions can lead to panic or incite unnecessary and costly control measures. (Take, for example, Egypt’s decision to slaughter all of the country’s 300,000 pigs despite no confirmed cases there, or an article in The Washington Post about the threat to the global economy.)

That said, now is the perfect time for journalists to begin investigating CAFOs in a responsible fashion. That means doing things a little differently than the early blog posts, which tended to have a finger-pointing tone, did not deliver much context about evidence and controlling for alternative hypotheses, and did not call experts to test their theories.

Those bloggers deserve credit for calling the press into action, however, for they obviously succeeded. It’s a fine line between asking tough questions and jumping to conclusions, and somebody has to walk it.

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Curtis Brainard writes on science and environment reporting. Follow him on Twitter @cbrainard.