Tag: Facts

We asked infectious disease experts what you can do to prevent the spread and how you can keep yourself and your pets safe during this outbreak.

Bird flu, also known as avian influenza or H5N1, is usually present in wild birds and poultry. In March, it was detected in dairy cows in the U.S. for the first time.

The particular subtype of virus taking hold now, a highly pathogenic avian influenza strain that originated in Europe and Asia, has been in the United States since late 2021. It was first detected in Massachusetts in early 2022, according to officials.

One person in Louisiana died from the illness last week, officials said, and 67 confirmed human bird flu infections have been reported in the U.S. since 2024.

However, experts said the risk of people catching the virus, let alone getting seriously ill, is small.

“The average person doesn’t need to be very concerned about bird flu right now,” said Dr. Daniel Kuritzkes, chief of the Division of Infectious Diseases at Brigham and Women’s Hospital.

Though the World Health Organization has reported a 54% fatality rate in humans with bird flu globally since 2003, Dr. David Hamer, professor of global health and medicine at the Boston University School of Public Health and a director at Boston University’s Center on Emerging Infectious Disease, said the subtype affecting birds and cattle in North America now is “much milder.”

Most people who have contracted the flu have had close, prolonged contact with animals who have the disease.

Jonathan Runstadler, chair of the Department of Infectious Disease and Global Health at the Cummings School of Veterinary Medicine at Tufts University, said many people ”are just getting very mild disease and usually just conjunctivitis.

The main concern remains that the virus will mutate into a form that is more contagious to humans.

“There’s a lot of worry that the more chances the virus has to infect people that it will make some changes that allow it to be a worse disease and a more transmissible disease,” Runstadler said.

Bird flu is usually spread through contact with secretions of an infected animal, Hamer said. For example, it can spread through bird flocks if an infected animal defecates in a body of water.

Runstadler said experts are not yet sure how livestock like cows get infected, though it’s likely because the virus gets into their feed or farm equipment.

The flu spreads to people when they breathe in virus particles or touch their eyes, nose or mouth after handling something that has virus particles on it. There has been no evidence of the virus spreading from human to human in the U.S.

The biggest risk is to those who work directly with livestock and poultry, experts said, and it’s important for those workers to take protective measures.

“Using respiratory precautions like wearing a mask and eye protection would be very helpful for people who have close contact with animals in that setting, whether it’s dairy animals or cattle being raised for slaughter,” Kuritzkes said.

Domesticated animals can get bird flu if they are in direct contact with an infected bird, experts said.

“Cats in particular are susceptible to this strain of virus and can die from infection,” Hamer said. “Owners need to keep their animals away from contact with birds, especially wild birds or the corpses of wild birds.”

Specifically, wild aquatic birds like ducks, geese, swans, and shorebirds are more likely to have the flu. With Massachusetts’ large population of wild geese, Hamer said it’s recommended dog owners prevent their pets from eating goose poop and clean their paws after contact with feces.

In addition to keeping animals away from birds and feces, experts said there could be an increased chance for infection if feeding a pet raw food, like raw milk or chicken.

The FDA is tracking cases of cats infected with the virus after eating contaminated food and warns that dogs and cats can get the virus if they eat raw food products from infected poultry or cattle.

“The advice would be the same for your pets [as you] at this point — if there’s even a small risk that what you’re feeding or consuming is sourced from an animal that might be affected with avian influenza, make sure you cook or treat that product appropriately,” Runstadler added.

Though pets themselves can get the virus, it’s unlikely they could pass it to humans. Contracting bird flu from a pet would require “a lot of very unlikely events to occur,” Kuritzkes said.

Songbirds and other common backyard birds are unlikely to carry viruses that are dangerous to poultry or humans, according to the Centers for Disease Control and Prevention, so it’s generally safe to keep bird feeders up.

However, Hamer said people should be on the lookout if birds start dying in their backyard.

“People need to be cautious if they see a dead bird — they want to call public health authorities in their jurisdiction to take care of it rather than have direct contact with it,” he said.

The main advice is to avoid direct contact with wild birds or other animals that could be infected with the flu, experts said. People should call public health or wildlife authorities if they need to dispose of a bird corpse so it can be properly tested.

If contact is unavoidable, it’s best to wear protective equipment like gloves and a mask, Hamer said.

Experts said it’s important to be vigilant about the virus and stay up to date on developments.

“This is a virus that is likely to continue to circulate in the wild and we’re likely to see occasionally these kinds of outbreaks, particularly seasonally as birds migrate who are carrying variants of the virus,” Runstadler said.

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Emily Spatz can be reached at emily.spatz@globe.com. Follow her on X @emilymspatz.