Is Bird Flu a Threat to Humans? UVA Expert Explains

As bird flu cases continue to rise in the U.S., UVA Health infectious diseases expert Dr. Patrick Jackson provided insights into the latest developments and potential risks during a media briefing. With over 60 confirmed human cases nationwide and recent detections in birds across Virginia, Maryland, and Delaware, concerns about the virus’s spread have resurfaced.

Jackson reassured the public that while the presence of bird flu in Virginia is noteworthy, it does not significantly change the risk level for humans. “We’ve known for a long time that H5N1 influenza, in its current strain, is widely distributed in wild bird populations,” he said. “The fact that it’s been detected in poultry operations in Virginia was something we expected to happen sooner or later.”

A new strain, H5N9, was recently detected on a California duck farm, raising questions about its implications. Dr. Jackson explained that while this strain appears less virulent than H5N1, multiple circulating influenza strains increase the possibility of viral mutations. “Every time you have co-circulating strains of influenza, you give the virus a chance to reshuffle its genome and possibly become more transmissible,” he noted.

Human Risk and Precautions

So far, human cases of bird flu in the U.S. have primarily been linked to direct contact with infected animals. According to Dr. Jackson, individuals most at risk include agricultural workers, poultry farm employees, backyard chicken owners, and hunters handling wild birds. “People who have backyard flocks should be very aware of their chickens’ health and take precautions when dealing with sick or dead animals,” he advised.

For the general public, however, the risk remains low. “If you don’t come into contact with cattle or birds regularly, there’s nothing you need to change about your daily routine to protect yourself,” he said.

Jackson also addressed concerns about the potential impact on the food supply. While avian influenza has led to rising egg prices due to mass culling of infected poultry, he reassured consumers that pasteurized milk remains safe. “We know that the virus is highly concentrated in raw cow milk, but pasteurization effectively inactivates it,” he explained. However, he cautioned against consuming raw milk, citing instances where cats became ill after exposure.

Communication and Monitoring Challenges

Some reporters raised concerns about delays in CDC updates regarding avian influenza. Jackson acknowledged the uncertainty, emphasizing the importance of real-time communication from health agencies. “We need CDC working closely with state and local health departments to monitor what’s happening in wild bird populations and among cattle,” he stated.

One major source of public health information, the CDC’s Morbidity and Mortality Weekly Report (MMWR), has not published an issue since January 2. “This report is essential for tracking foodborne outbreaks and infectious diseases, including avian influenza. The current pause in updates creates a gap in information,” Dr. Jackson said.

What to Watch For

While bird flu remains primarily an animal health issue, Jackson noted that the biggest red flag for a human pandemic would be sustained human-to-human transmission. “Right now, we haven’t seen that. The infections that have occurred in humans have been isolated cases from direct contact with animals,” he said. However, he warned that the situation could change rapidly: “There is no bright line between where we are now and the onset of human-to-human transmission. That could happen never, or it could happen tomorrow.”

For now, he advised those in close contact with birds or cattle to follow CDC protective measures and hygiene guidelines. “Being aware of the risks and taking appropriate precautions is key,” he said.

UVA Health, which operates Prince William Medical Center in Manassas and Haymarket Medical Center in Prince William County, continues to monitor the evolving situation.