Here’s what you need to know.

Is pasteurized milk safe to drink, even if it has bird flu virus particles?

In short, yes.

The pasteurization process kills harmful bacteria and viruses, and experts say that translates to H5N1 particles, too.

Elyse Stachler, a research scientist at the Broad Institute who conducted the testing, said the presence of H5N1 particles in the milk suggests that a cow providing milk was infected but not that the pasteurized milk contains live virus. Because the sample that tested positive was processed outside of New England, it’s unlikely that this infected cow is local to our region.

Experts point to the success of pasteurization in preventing the spread of infection, even if infectious particles are present.

What is the difference between raw and pasteurized milk?

Pasteurization is the process of heating milk to a high enough temperature to kill off any harmful germs. Raw milk is milk that has not been pasteurized.

Pasteurization of milk began in the 1920s when millions of people became sick and died of tuberculosis, scarlet fever, typhoid fever, and other diseases that were spread through raw milk.

Is raw milk safe to drink?

The CDC calls raw milk one of the “riskiest foods.”

While advocates say the beneficial bacteria in raw milk can promote health, the FDA and CDC both advise against consuming it, citing long standing information regarding the increased risk of foodborne illness associated with numerous pathogens that may be present in milk that does not undergo pasteurization.

In Massachusetts, raw milk is not sold in grocery stores and can only be purchased at select farms.

“We do not know exactly what sort of infections humans could contract from drinking raw milk containing infectious H5N1, but nobody should want to find out the answer the hard way,” said Bill Hanage, associate professor of epidemiology at Harvard T.H. Chan School of Public Health.

Last month, around 24 cats on a dairy farm in Texas contracted H5N1 from consuming raw milk from cows infected with H5N1; more than half of the cats died.

Should I be worried about my ice cream, yogurt, cottage cheese, etc.?

Samuel Alcaine, associate professor of food science at Cornell University, said dairy items found in most supermarkets are pasteurized and therefore don’t pose a health risk.

“There wouldn’t really be much of a difference in risk between fluid milk and, say, cottage cheese or ice cream,” Alcaine said.

Experts said the prominent danger in consuming dairy products is when the products are not pasteurized, like some cheeses made with raw milk.

“Studies have shown that pasteurization is an effective way to control a virus and eliminate it,” Alcaine said.

How much testing does store-bought milk undergo?

There are regulatory standards to ensure that milk products are safe before they go on store shelves.

Alcaine pointed to the FDA’s Pasteurized Milk Ordinance, which ensures milk is up to Grade “A” standards and approved by public health authorities before entering the market. (More than 90 percent of milk produced in the US is Grade A.)

The grading process looks at bacterial and white blood cell counts in milk that could indicate the presence of a sick cow. If the counts exceed certain levels, the milk is pulled from the supply.

Matthew Moore, an assistant professor at UMass Amherst who focuses on food safety microbiology, said there should be more testing of raw milk.

“In terms of the commercial pasteurized milk and dairy products you buy, our country does a pretty good job of ensuring they’re safe,” he said.

What about the safety of farm workers?

Public health experts are concerned about the health of agricultural workers who may come in contact with infected cows. (So far this year, only one worker has tested positive for the virus; the worker had a mild illness and has since recovered.)

Some experts have said those who work on dairy farms should have broader access to testing and protective equipment.

Alexa Coultoff can be reached at alexa.coultoff@globe.com. Follow her @alexacoultoff.