Scientists already discovered that raw milk can harbor the infectious H5N1 bird flu virus, but now there’s a new study on its capabilities that has health officials concerned.

Researchers found that the bird flu virus is also stable and still infectious in cheese that has been made with raw milk despite being aged for months at a time.

The study, which has not yet been peer-reviewed, was done by scientists at Cornell University and funded by the U.S. Food and Drug Administration and the state of New York.

Raw milk cheeses are made with milk that hasn’t been heat-treated or pasteurized yet. Regulations in place require the cheese to be aged for at least 60 days and — unlike raw milk — cheese made with raw milk can be sold across state lines.

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The Cornell study involved making cheese with milk that had been spiked with the active bird flu virus under different pH levels in the acidic range.

The tests showed the infectious virus remained throughout the cheese-making process, the study said.

The findings raise concerns about food safety.

“Our study highlights the potential public health risks of consuming raw milk cheese, underscoring the need for additional mitigation steps in cheese production to prevent human exposure to infectious virus, the researchers wrote. “Although the infectious dose of the virus to humans is not known, ingestion of contaminated raw dairy products repeatedly may increase the probability of infections.”

There's a variety of cheeses that are made with raw milk including Parmigiano Reggiano, comte and raclette

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