By Stephen Smoot
Despite the sporadic outbreaks of the Highly Pathogenic Avian Influenza H5N1 strain over the past year, the United States Centers for Disease Control on Christmas Eve shared that “the risk to the general public has not changed and remains low.”
Over the past several months, the CDC has studied a Louisiana case where a farm worker contracted the virus. They determined that the virus in the patient mutated slightly after infection as it interacted with his body, but that the changes were not significant and “closely related to existing” strains that “could be used to make vaccines if needed.”
Last May, the CDC issued guidance concerning the potential for humans to contract the virus. It read “infected birds shed avian influenza viruses through their saliva, mucous, and feces.”
That said, other animals can contract the virus and transmit it. As the CDC states, “other animals infected with avian influenza viruses may have virus present in respiratory secretions, different organs, blood, or in other body fluids, including animal milk.”
Jessica Hoover, a West Virginia University Extension Agent based in Pendleton County, urged that “if milk is unpasteurized, it can be transmitted through . . . raw milk” to humans. The CDC concurs, saying that “Anyone, even healthy adults, can get sick from drinking raw milk.”
The virus can also transmit to humans through the eyes, nose, the mouth, or through inhaling it. The CDC states that “this can happen when virus is in the air (in droplets, small aerosol particles, or possibly dust)” A person can ingest the virus if it deposits on mucous membranes, if breathed in, “or possibly when a person touches something contaminated by viruses and then touches their mouth, eyes, or nose.”
The H5N1 strain emerged in 2020 with what the CDC calls “gene swapping” between viruses in domestic poultry and wild birds. Europe saw the strain initially and from there it spread across the Eastern Hemisphere. That year, five humans in China contracted the virus.
Wild foxes in Russia and the Baltic states were also discovered to have it in 2021. By the next year, it was blamed for the death of large numbers of sea lions on the Peru coast and was found in commercial turkeys in the United States.
Last month, the New England Journal of Medicine published an article on the increasing frequency of humans contracting H5N1. It states that “most case patients presented with conjunctivitis, almost half with fever, and a minority with mild respiratory symptoms.”
The most severe case came in Canada with a 13 year old girl already experiencing asthma and obesity. She “presented with conjunctivitis and fever and had progression to respiratory failure.”
Because of the rarity of such cases, as the NEJM states “the CDC still designates the risk of HPAI A (H5N1) to most Americans as low” and vaccines are available if the threat elevates. It goes on to say, however, that “a balance between enhanced vigilance and ‘business as usual’ is needed” because “the past weeks have seen more cases detected in more states as well as more persons with respiratory illness acquired through exposure to poultry or from an unknown source.”
The CDC states that it is “watching the situation carefully and working with states to monitor people with animal exposures.”
