Houston, Texas – A recent study conducted by the Centers for Disease Control and Prevention has revealed concerning findings regarding the strain of the H5N1 bird flu virus isolated from a dairy worker in Texas. The virus was found to be 100 percent fatal in ferrets used to simulate influenza illnesses in humans but showed inefficiency in spreading through respiratory droplets.
Unlike seasonal influenza viruses that typically circulate among humans without causing fatalities in ferrets, the H5N1 strain from the Texas individual demonstrated a lower rate of transmission through respiratory droplets, suggesting the need for genetic changes to achieve efficient airborne spread. The CDC emphasized the importance of respiratory droplet spread for sustained person-to-person transmission.
In the study, all six ferrets infected with the H5N1 strain developed severe illness and ultimately succumbed to the virus. Experiments conducted by CDC scientists indicated that direct contact with infected ferrets led to transmission in all healthy ferrets placed together. Furthermore, respiratory transmission tests showed a delayed and less efficient spread of the virus compared to seasonal influenza viruses.
These results echo previous findings from ferret studies involving H5N1 isolates collected before the current outbreak among US dairy cows, highlighting the lethal nature of the virus in ferrets. The CDC emphasized that while the overall risk to the general public remains low, individuals in close contact with infected animals, particularly those working in dairy and poultry farms, are at higher risk.
Despite the mild cases reported in human infections with the H5N1 virus so far, the CDC cautions that the potential for serious illness among individuals cannot be overlooked. The current global outbreak has seen four cases of H5N1 in the United States, all among individuals working in the agricultural sector. With confirmed cases in 85 dairy herds and one alpaca farm across multiple states, vigilance and precautions remain essential to prevent further spread of the virus.