Cows infected

Another case of bird flu in US dairy worker

There is a particular risk of transmission with raw milk.(Bild: AP)

A second case of bird flu in humans has been confirmed in the USA. As with the first case, a worker at a dairy is affected, the US Centers for Disease Control (CDC) announced on Wednesday. The new case occurred in Michigan.

According to the US state, the worker had regular contact with cows infected with bird flu. However, the risk to the general public remains low, the CDC stated.

The bird flu virus was first detected in dairy cows in the USA in March. In April, an infection had already been confirmed in a dairy farmer in Texas. Similar to there, the patient in Michigan also showed only mild symptoms, according to the CDC. The worker in Michigan recovered, according to the state's Department of Health.

There is a particular risk of transmission with raw milk.(Bild: AP)

High virus concentration in raw milk
Michigan and Texas are among the nine US states where avian influenza has now been detected in dairy herds. Scientists believe the outbreak is more widespread, as authorities have found particles of the H5N1 avian influenza virus in about 20 percent of retail milk samples.

The H5N1 virus under the microscope(Bild: AP)

The CDC stated that given the high concentration of virus in raw milk from infected cows and the extent of spread in dairy cows, additional human cases could occur.

According to the authorities, it is not clear exactly how the virus spreads. In order to limit transmission, it has been mandatory since the end of April for dairy cows to be tested negative before being transported across state borders.