(Wall Street Journal) – With so much H5N1 virus circulating across the U.S., scientists worry we are a few mutations away from a potential human pandemic

Though there are only 68 confirmed cases in people—largely dairy workers—public-health officials think bird flu is likely more widespread. Last week, a Centers for Disease Control and Prevention report documented three asymptomatic cases in veterinarians who took care of cattle they didn’t know had H5N1.

What is clear is that people working on farms are sporadically contracting the virus. What hasn’t yet happened—and scientists believe has yet to happen in the history of the virus—is sustained human-to-human transmission. (Read More)