A second person has been infected with bird flu in the United States, less than two months after a first case in the country. The American giant is currently affected by an epidemic of avian flu in cows, but the authorities judge that the assessment of the risk for the population remains “low”.
Less than two months after a first case, a second person was infected with avian flu in the United States in connection with an epidemic of this virus in cows in the country, American health authorities announced on Wednesday. This person works on a farm where the H5N1 virus infected dairy cows, in the state of Michigan (north), said the Centers for Disease Prevention and Control (CDC).
The WHO expressed its “huge concern”
For this federal public health agency, however, the risk assessment for the American population remains “low”. A first case in Texas, in the southern United States, was announced on April 1. It was then “probably” the first worldwide case of avian flu infection via a cow, according to the CDC. A first human case of avian flu was discovered in the country in 2022, in Colorado (west), but it was then an infection by poultry.
For the person infected in Michigan as in Texas, the patients only showed symptoms in the eyes, specifies the CDC. Both have recovered. Experts are concerned about the growing number of mammals infected with the disease, although cases in humans remain rare. There is no evidence of human-to-human transmission at this time, but scientists fear that high circulation could facilitate a mutation of the virus that would allow it to pass from one human to another.
The World Health Organization (WHO) expressed its “tremendous concern” in mid-April about the increasing spread of avian flu to new species. Goats, for example, have joined the list.
Additional possible cases
Cattle herds in at least nine US states are affected by this outbreak. The first report dates from March 25. The United States Department of Agriculture (USDA) has identified transmission of the virus between cows within the same herd, or between dairies during animal movements. The cows are recovering and the disease is associated with “little to no mortality,” according to a ministry press release at the end of April.
“It is important to emphasize that so far, we have not found any modification of the virus that would make it more contagious to humans or between people,” added this press release. Financial aid has been put in place by the USDA to help affected farms, for example to provide protective equipment to their employees. The CDC on Wednesday again emphasized the importance of precautionary measures for people exposed to sick or potentially infected animals.
These people must in particular avoid “close, prolonged and unprotected” contact with these animals, as well as with their excrement, or even with unpasteurized raw milk. “Given the high levels of H5N1 virus in raw milk from infected cows, as well as the extent of spread of this virus among dairy cows, additional similar cases in humans may be identified,” the CDC said .
But “sporadic infections in humans – without continued spread – will not change the risk assessment for the general public,” they added. At the end of April, the United States Medicines Agency (FDA) confirmed that milk sold in stores in the United States was “safe”, the pasteurization process being “effective” in killing the avian flu virus.
