City hospitals are actively reviewing their outbreak policies but say there’s no reason to worry about H5N1, or bird flu, in humans just yet.

On Thursday, another farm worker came down with bird flu, marking the third human case in the U.S. tied to the outbreak in dairy cows. While the case was in Michigan, New York is home to many poultry and dairy farmers, making it conceivable that the outbreak could spread locally, as U.S. Sen. Kirsten Gillibrand noted in her call on the White House on May 20 to strengthen interagency coordination in the event of an outbreak.

If the strain of the virus referred to as H5N1 became widespread in humans, it would be significantly more contagious and potentially a lot more deadly than Covid-19, according to Dr. Bruce Farber, chief of public health and epidemiology at Northwell.

While Farber said the virus has not spread to humans in any way that is “significant,” he noted that hospitals would be “foolish and naive” if they didn’t think that could happen sometime down the road.

As such, local health systems are reviewing their health policies, staging drills and ensuring they have the proper equipment.

Many hospitals have also stockpiled personal protective equipment to keep their health care workers safe, according to Dr. Michael Redlener, co-director of the Center for Healthcare Readiness at Mount Sinai, noting that the recommended PPE is very similar to what was needed for Covid-19. Redlener added that Sinai has identified more PPE manufacturers in North America to ensure that supply chain issues do not compromise their access.

But while Covid-19 was “quite the dress rehearsal,” Farber said, there are still some elements of unpredictability. For example, PCR tests – which identify active viruses in the body – cannot currently detect the specific H5 strain, posing a challenge to identifying and tracking cases.

The absence of an existing PCR test for H5 makes it tricky to identify when the virus could hit local hospitals, said Dr. Michael Phillips, chief epidemiologist at NYU Langone.

NYU has resorted to investigating every flu infection that manifests as a respiratory illness in hopes of catching the virus before it spreads. Clinicians send strains that look concerning to be sequenced at the Wadsworth Center, the state Health Department’s public health laboratory, Phillips said.

NYU is also closely surveilling symptoms. Phillips said the health system is watching its databases for an uptick in cough, for example, to stay on top of a potential outbreak. “Our ears are up and ready to go,” he said.

For now, hospitals remain vigilant. Phillips said that while sporadic transmission of the virus from animals to humans is somewhat expected, it’s encouraging that there has been no sustained spread from human to human.

“Until then, the risk of a full-blown pandemic remains very, very low,” Phillips said.