Second human bird flu case linked to dairy cow outbreak reported in US
A second case of bird flu from raw cow milk has been found in a human in US.
US health authorities reported another case of bird flu in a person on Wednesday (May 22), less than two months after the first case. This comes as the disease spreads widely among dairy cows. Both individuals, one in Texas and the other in Michigan, caught the virus known as H5N1. They were dairy farm workers who had mild symptoms and have since gotten better, according to officials. Even with this second case, the US Centers for Disease Control and Prevention said the risk to the public is still "low." However, they anticipate more cases in the future.
Given the high levels of the virus "in raw milk from infected cows, and the extent of the spread of this virus in dairy cows, similar additional human cases could be identified," the CDC said.
"However, sporadic human infections without ongoing spread will not alter the CDC's assessment of low risk for the US general public," it further said.
The most recent case in Michigan involved "a worker on a dairy farm where the H5N1 virus has been detected in cows," the CDC reported. According to the Michigan Health and Human Services, the worker experienced mild symptoms and has since recovered. Samples were taken from the worker's nose and eye, with only the eye sample testing positive for the virus. Similar to the Texas case, the patient only reported symptoms in the eye, the CDC added. As of Wednesday, 52 US herds across nine states have been infected with bird flu. The CDC noted that individuals with close or prolonged, unprotected contact with infected birds or other animals, including livestock, face higher infection risks. While the current H5N1 strain has caused widespread poultry deaths, affected cows have shown less severe illness. The infection of cows and goats in March surprised experts, who previously thought these animals were not susceptible to this type of flu. Although virus fragments have been detected in pasteurised milk, health authorities reassure that milk sold in US stores remains safe due to effective pasteurisation. Currently, there is no evidence of human-to-human transmission, but officials remain concerned that the virus could mutate and become transmissible between humans. Avian influenza A(H5N1) first emerged in 1996, with outbreaks in birds increasing significantly since 2020, alongside a rise in infections among mammals. Also read | Bird flu in raw cow milk kills more than half of cats on Texas farm