Bird Flu (H5N1) Outbreak Among Cattle Raises Concerns

A global outbreak of H5N1 bird flu, which began in 2020, has recently spread among cattle in several U.S. states and marine mammals worldwide. This has prompted health officials and experts to closely monitor the situation, as there is concern that the virus could mutate and eventually spread to humans, although human cases are rare. The outbreak has led to the death or slaughter of dozens of cows in Colorado, Ohio, Michigan, South Carolina, and Texas. This is unusual because cows are more costly to slaughter compared to poultry, and around 90% usually make a full recovery. In addition to affecting cattle, a new study has found that the 2023 bird flu outbreak in South America resulted in the deaths of around 17,400 elephant seal pups and 24,000 sea lions, marking the first known case of transnational mammal-to-mammal bird flu transmission.

The impact of bird flu on humans has also been observed. A dairy farm worker in Michigan has been infected with bird flu, marking the first human case in the U.S. linked to respiratory symptoms. However, the worker’s symptoms are reportedly resolving. Another human case was reported in Australia, where a child became infected after traveling to India. Despite suffering from a severe infection, the child has since recovered. In the U.S., a Texas dairy farmer also contracted bird flu but experienced only pink eye and is recovering.

Research has shown that the virus can spread through infected milk, highlighting potential transmission risks. However, a study conducted by the USDA found that cooking beef at medium to well-done temperatures eliminated the virus, while lower temperatures did not. Additionally, ground beef products tested negative for bird flu, affirming the safety of the meat supply. The FDA has confirmed that pasteurized milk is safe to consume, as the virus remnants in pasteurized milk are deactivated by the heat during the pasteurization process.

While the risk of bird flu spreading between humans remains low, ongoing monitoring and preventive measures are crucial to manage the outbreak’s impact on both animal and human health. The USDA has been monitoring and testing ground beef samples for safety, and public health officials continue to closely monitor the situation.