Third Human Case of Bird Flu Confirmed, First Case With New Symptoms

A third human case of bird flu has been identified in Michigan, according to the U.S. Centers for Disease Control and Prevention (CDC). This marks the second case in Michigan, and the third associated with an ongoing multi-state outbreak of bird flu in dairy cows. All human cases have been found in dairy farm workers exposed to infected cows, making it another instance of probable cow-to-person spread.

While the CDC said bird flu risk to the public remains low, this new case reported more typical symptoms of acute respiratory illness associated with influenza virus infection, including A(H5N1) viruses. The Michigan dairy worker, who was exposed to different infected cows than the case reported last week in Michigan, reported upper respiratory tract symptoms including cough without fever, congestion, sore throat, and eye discomfort with watery discharge. A human case with respiratory symptoms with not unexpected, but it does increase the odds of spreading, the Associated Press (AP) reported.

The CDC is closely monitoring data from influenza surveillance systems, particularly in affected states, and no signs of unusual influenza activity in people, including no increase in emergency room visits for influenza and no increase in laboratory detection of human influenza cases, have occurred. The CDC did emphasize the importance of recommended precautions in people with exposure to infected or potentially infected animals, including livestock and birds.

Additionally, about 220 people are being monitored in Michigan because of potential exposure to bird flu, CNN reported. While dairy herds in nine states have been infected with bird flu, Michigan is the state with the highest number of dairy herds (22) reported to be infected, according to the American Veterinary Medical Association. Texas, which reported the first human case of bird flu, is second with 15 herds infected.

Earlier this spring, the first person in the U.S. tested positive for bird flu after he was exposed to infected dairy cattle in Texas. In May, the CDC recommended farm workers wear personal protective equipment (PPE) to combat bird flu spread, as CMM previously reported. Neither of the Michigan dairy workers wore PPE, and the CDC emphasized PPE is an important tool in preventing spread, the AP reported.

Additionally, in May, the CDC recommended that testing for influenza remains strong this summer with heightened testing of the influenza A virus. The CDC hopes the increased samples submitted will help detect rare cases of human bird flu infections.