This week, Washington State reported four cases of human avian influenza at a chicken farm, marking it as the sixth state to encounter similar cases. The total number of infected individuals nationwide has reached 31. While experts indicate that the risk of human-to-human transmission remains low, they express concern about the ongoing spread of the avian flu virus among livestock.
As flu season approaches, the potential for risk increases if two strains of the flu virus infect the same host and exchange genes, leading to the emergence of new variants. The avian flu virus continues to circulate among bird populations, poultry, and livestock.
On October 22, the Centers for Disease Control and Prevention (CDC) announced that following the confirmation of four farm workers infected in Washington, the national total of confirmed cases rose to at least 31. Flu experts warn that if the virus continues to spread among animals, the possibility of a larger outbreak among humans cannot be ruled out.
Dr. Amber Itle, a veterinarian in Washington State, commented, “The longer this virus remains in the environment, the more it spreads among animals, and the more mutations may occur that we may not understand or be able to predict. This raises concerns about whether we could be facing the next global pandemic.”
Public health officials, however, state that there have been no significant genetic changes in the avian flu virus so far, and there is currently no evidence of sustained human transmission. Umair Shah, the secretary of the Washington State Department of Health, noted on October 20 that the lack of evidence for continuous human transmission is a positive sign. A CDC spokesperson confirmed on October 23 that a team of experts has been deployed to assist in Washington State, and they reassured the public that there is presently no significant threat.
Despite the lower risks for the general public, frontline farm workers seem to be facing heightened dangers. The four infected individuals were all involved in culling chickens at an egg-laying facility due to an outbreak of the virus. They became infected through close contact with the infected flocks.
The affected farm is located in Franklin County in southeastern Washington and houses approximately 800,000 chickens. While performing euthanasia duties, workers utilized protective gear, including goggles, respirators, and high-density polyethylene protective suits. However, despite these precautions, they reported experiencing mild respiratory symptoms and conjunctivitis after work, although the conditions were not severe enough to require hospitalization.
The only known case of infection without animal contact is in Missouri, which the CDC is currently investigating.
