(The Hill) — The Food and Drug Administration (FDA) has found that about 1 in 5 samples of retail milk contain traces of highly contagious bird flu, though these findings may not be indicative of an infectious risk to consumers.

In an update published this week, the FDA shared some takeaways from its nationally representative commercial milk sampling study.

“The agency continues to analyze this information; however, the initial results show about 1 in 5 of the retail samples tested are quantitative polymerase chain reaction (qPCR)-positive for [Highly Pathogenic Avian Influenza] viral fragments, with a greater proportion of positive results coming from milk in areas with infected herds,” the update stated.

The FDA noted that additional testing will be required to determine if intact pathogens are actually present in the milk and if consuming these products poses a risk of infection.

“To date, the retail milk studies have shown no results that would change our assessment that the commercial milk supply is safe,” the agency shared, citing the pasteurization process that retail milk undergoes as well as the diverting and destroying of milk from infected cows.

The agency also reiterated its long-standing warning against drinking raw milk.

Earlier this year, a worker on a dairy farm was confirmed to have been infected with a highly infectious strain of bird flu in Texas. The individual worked close to cows that were found to be infected with the H5N1 strain.

According to William Schaffner, professor in the division of infectious diseases at the Vanderbilt University School of Medicine, pasteurization should kill the virus and people generally shouldn’t be too concerned about buying milk from a grocery store.

“A bird flu virus can pick up the capacity to spread readily from person to person. This is a rare event, every 15 years or so. There’s no indication that the current bird flu virus has picked this up but it’s out there circulating,” Schaffner told The Hill.

He emphasized that while bird flu infections are rare in the U.S., it is not a novel virus. And it is even rarer that someone infected by livestock ends up passing that virus on to another person.