I have tracked deadly, massive outbreaks of H5N1 avian influenza in poultry for the past two decades. Hundreds of millions of birds have died, and there has been frequent spillover to other species, including mink, seals, foxes, skunks and even dogs and cats.

This week, the nation's largest supplier of eggs stopped production after birds at a plant in Texas tested positive. About 2 million chickens were slaughtered to prevent spread of the illness. The Centers for Disease Control and Prevention also reported that a person in Texas had contracted the flu but is displaying only mild symptoms.

The public has worried at times about a massive human pandemic, but since 2005, the structure of the bird flu virus has not changed significantly.

That is extremely good news, especially when you consider that gain-of-function research conducted in Dr. Ron Fouchier’s lab in the Netherlands in 2011 revealed the mutations needed for bird flu to pass from human to human. Monitoring of the virus in nature has shown that those........

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