Rising Bird Flu Cases in U.S. Spark Concerns Over Testing Limitations and Mystery Infections

 

The spread of bird flu in the United States is raising concerns as the number of cases climbs, yet limited testing access remains an issue. New tests developed by commercial labs will soon be available with a prescription, but their use will be restricted to individuals with close contact to animals or animal products, despite unexplained cases in Missouri. Officials worry that factors such as wild bird migration and extreme weather may increase chances of the virus jumping to humans.

In Missouri, a second individual tested positive for H5N1 with no known animal exposure, the CDC reported. This person lives with the initial patient who tested positive a few weeks ago, both developing symptoms at the same time. Health workers who treated the initial case, however, all tested negative, indicating the infection was not transmitted to them.

The exact source of these Missouri cases remains unknown. While Quest Diagnostics and other labs are developing bird flu tests, they will only be recommended for individuals with known animal exposure. CDC officials stress the need for more frequent H5N1 checks in flu cases, as this method led to the discovery of Missouri’s initial infection.

Washington has also reported human cases of bird flu among poultry workers who handled infected birds, with two confirmed and five presumed cases. CDC Deputy Director Nirav Shah has called for improvements in safety measures for workers, including antiviral treatments and better protective gear, as many infections occur in crowded, poorly ventilated conditions.

Currently, there are 31 confirmed human cases of H5N1 in the U.S., with no severe or hospitalization-required cases in Missouri, Washington, or California. Nearly half of these cases are from California, where veterinarian Crystal Heath documented potential biosecurity risks at a large dairy farm with infected cattle.

Agriculture Department officials, including Eric Deeble, are investigating high mortality rates in these infected cows, considering factors like heat, management practices, and animal density. With fall bird migration underway, health authorities remain vigilant, particularly among poultry workers at risk of new infections.