In January 2022, health officials detected a H5N1 outbreak in wild birds — the first of its kind since 2016, according to the Centers for Disease Control. One month later, H5N1 hit a commercial poultry facility, infecting multiple turkeys.
Since then, H5N1 has been detected in more animals, including cattle, goats, alpacas, and, most recently, a pig.
The increase in avian influenza activity is due to a major outbreak occurring in wild birds that has been ongoing and has spilled into poultry farms and now dairy cattle,” Dr. Amesh Adalja, an infectious disease expert and senior scholar at the Johns Hopkins University Center for Health Security, told HuffPost.
The main difference between this outbreak and previous ones is that dairy cattle are being infected with H5N1 for the first time ever.
Previously, health officials did not think cattle could get influenza, according to Bowman. “There’s no flu vaccine for cattle, and the dairy industry hasn’t seen anything like this before,” he said.
The pig’s case also concerns infectious diseases experts because pigs can be infected with both human and avian viruses, which can produce a re-assorted virus. This essentially is when two viruses in the body exchange genetic material, a process that could “generate a novel influenza virus that may be readily able to infect and be transmitted between people,” said Dr. Richard Martinello, a Yale Medicine infectious diseases specialist.
These types of re-assorted viruses caused the influenza pandemics of 1957, 1968, and 2009, according to Adalja.
