Bird Flu Infection Risk: CDC Advisory Alert

The recent alert from the CDC has raised concerns about the potential for infections with the highly pathogenic avian influenza (HPAI) A(H5N1) virus, also known as bird flu. The advisory comes in light of a case where a farmworker on a commercial dairy farm was infected with the H5N1 virus after exposure to presumably infected cattle. This incident marks the second case in the U.S., following one in 2022 in Colorado. What stands out about this new case is that it is the first presumed transmission from a cow to a human amidst an outbreak of the virus in dairy cattle.

The CDC alert emphasizes that the current risk of these viruses to the public remains low. However, individuals with job-related or recreational exposures to potentially infected animals are at a higher risk of infection. Clinicians and health departments are advised to consider the possibility of H5N1 infection in individuals showing signs or symptoms of acute respiratory illness and/or conjunctivitis, especially if they have had recent exposure to potentially infected animals or their environments.

Symptoms of bird flu can vary from mild upper respiratory illness to severe systemic disease. The recent case only presented with mild conjunctivitis as the sole symptom. It is worth noting that there has been no identified human-to-human transmission of the virus. Despite this, individuals who have had contact with infected animals or their environments are urged to seek medical attention if they develop symptoms or have relevant exposure history.

As a precautionary measure, individuals suspected of H5N1 infection should isolate themselves from household members and refrain from attending work or school until test results confirm they are not infected with the virus. The advisory also recommends post-exposure prophylaxis with oseltamivir (Tamiflu) for close contacts of infected individuals.

While the risk of bird flu transmission to humans remains low, it is essential for clinicians and health departments to remain vigilant and consider the possibility of H5N1 infection in individuals with relevant exposure history. Early detection and appropriate preventive measures are key to preventing further spread of the virus.