Public health crises often begin quietly. The world learned of the COVID-19 pandemic through an unassuming announcement by an outbreak alert service called ProMED-Mail of “pneumonia of unknown etiology.” Similarly, late last March, the Texas Animal Health Commission released a relatively bland memo announcing that H5N1 highly pathogenic avian influenza – better known as “bird flu” – had been detected in dairy cows from four herds in Texas and Kansas. The first detection in cows was an unwelcome surprise, since influenza A viruses were not thought to infect cattle. However, the risk to humans was judged to be low. Within a week, an infected dairy worker was identified.
In the year since then, there have been more than 70 detected human cases in the US – though that number is expected to be a vast undercount. Dairy herds have been infected in 16 states, and new outbreaks occur at poultry farms with increasing frequency. Egg prices have soared. Cats have died from consuming infected raw milk and contaminated meat. Multiple species of wild animals, ranging from penguins to seals to bears, have been found dead from H5N1 infections. ….more
