Could Avian Influenza Be The Next Covid-19?

In early April, the Centers for Disease Control and Prevention (CDC) notified the public that an individual in Texas had tested positive for highly pathogenic avian influenza (HPAI), or bird flu. This person experienced conjunctivitis — or redness of the eyes — as their only symptom after being exposed to dairy cattle that were presumed to be infected with HPAI. This was the second documented human case of avian influenza in the United States since 2022, and has escalated concerns for a large outbreak — or potentially a pandemic — in the human population.

Influenza viruses, which cause annual epidemics of mild to severe respiratory illness, are not unique to humans. Certain subtypes of influenza circulate among animals, including birds, swine, horses, dogs and bats. Infection in some animals, such as wild waterfowl, may be asymptomatic (i.e., no disease results from the infection) and these animals are considered a natural reservoir for the virus. However, transmission of the virus to other animals, such as backyard bird flocks or commercial poultry, may have devastating consequences.

Since January of 2022, the largest outbreak of avian influenza in recorded history has occurred worldwide. To date, a subtype of highly pathogenic avian influenza — known as H5N1 — has been detected in over 9,000 wild birds and has affected greater than 90 million poultry in the United States. Recently, the virus has been identified in certain mammals, including dairy cattle, prompting concern that it may be adapting for more efficient transmission among mammalian species. Although sequencing studies have not yet demonstrated this to be the case, the recent human case in Texas has some asking, “Could avian influenza result in the next pandemic?”