The Centers for Disease Control and Prevention (CDC) have issued a warning regarding the risk of infections with the highly pathogenic avian influenza (HPAI) A(H5N1) virus, commonly known as bird flu, in individuals who have been exposed to potentially infected animal sources. This alert follows the recent case of a farmworker on a commercial dairy farm in Texas who was diagnosed with the H5N1 virus after being in contact with cattle that were presumed to be infected. What makes this case particularly concerning is that it was the first known instance of presumed transmission from a cow to a human in the United States.
It is important to note that, despite this recent case, there have been no reports of human-to-human transmission of the virus, and the risk to the general public is considered to be low. However, individuals with occupational or recreational exposure to potentially infected animals are at a higher risk of infection. Symptoms of H5N1 infection can vary from mild respiratory issues to severe systemic illness, with the recent case presenting with mild conjunctivitis as the only symptom.
Clinicians and health departments are advised to be vigilant in considering the possibility of H5N1 infection in individuals presenting with signs of acute respiratory illness and/or conjunctivitis, particularly if they have a history of exposure to potentially infected animals. This exposure may include contact with sick or dead birds, livestock, or other animals, as well as direct contact with contaminated surfaces or animal products. Individuals who have had prolonged contact with infected animals in confined spaces are also at an increased risk.
In the event of suspected H5N1 infection, patients should be encouraged to isolate themselves from others, refrain from going to work or school, and follow proper hygiene practices to prevent further spread of the virus. Post-exposure prophylaxis with antiviral medication may be recommended for individuals who have been in close contact with an infected individual. It is essential for clinicians to remain vigilant and proactive in identifying and managing cases of avian influenza to prevent potential outbreaks in the future.