Health officials are warning people with certain health issues not to swim in Massachusetts coastal waters or eat raw shellfish. This comes after one person contracted a flesh-eating bacteria known as Vibrio vulnificus after swimming at a Falmouth beach last week.
At the same time, experts say the bacteria is unlikely to cause illness in generally healthy people.
"It's a particular risk to those who have underlying medical conditions, such as liver disease, [or are] immunocompromised from drugs or cancer. Even diabetes can increase the risk of this infection," said Dr. Larry Madoff, medical director for infectious disease at the state Department of Public Health.
People can get infected through an open cut or wound, Madoff said — including a recent piercing or tattoo. They can also be infected by ingesting raw or undercooked shellfish that pick up the bacteria.
Still, infectious disease experts say healthy people who don't have complicating factors don't need to be too worried.
"The typical person who's healthy, whose skin is intact, has really no reason to be concerned," said Dr. Daniel Kuritzkes, who heads the Division of Infectious Diseases at Brigham and Women's Hospital. "And the typical person wouldn't have to be concerned about eating clams and oysters, for example."
For those who are infected, though, the bacteria can progress quickly and prove deadly.
"The reality is that it spreads so quickly and many people don't get to care quickly enough to prevent the severe consequences, including amputation [and] severe sepsis," said Dr. Shira Doron, chief infection control officer at Tufts Medicine Health System. She said it's good for people to be on the alert, because if doctors catch the infection quickly and prescribe treatment, they can prevent the worst outcomes.
The exposure happened at Old Silver Beach in Falmouth. The Department of Public Health did not disclose the condition of the infected patient. The town notes that there is no advisory or closure in effect for the beach.
"Cape Cod's beaches are an important part of our economy, culture, and community," Scott McGann, health agent for the town of Falmouth, said in a written statement. "By taking a few simple precautions, residents and visitors, and particularly anyone who is vulnerable or immunocompromised, can continue to enjoy them safely."
While Vibrio vulnificus infections are rare in Massachusetts, they're not unheard of. According to the state's public health department, there have been seven confirmed cases among Massachusetts residents in the last two years. Of those, three patients likely were infected in other states and four were likely exposed in Massachusetts.
And many agree the bacteria could become more common in the Northeast. Madoff noted that historically, it used to be found further south in Gulf Coast states.
"Increasingly it seems to have moved north," he said. "So I do think it's associated with warming waters."
Massachusetts has already had several heat waves this summer, contributing to warmer-than-usual water temperatures. And Doron notes that as the climate continues to warm, the bacteria could become more common in Massachusetts.
"That is not necessarily an epidemiologic phenomenon that we are already seeing, but it is something that we have to be watchful for," she said. "And we are seeing that with other diseases, specifically mosquito-borne diseases, like way more dengue virus in the United States than we typically see in the past."
And just like mosquitoes, creatures like ticks and microorganisms like Vibrio vulnificus are making their way up to New England.
"This is another example of the kinds of health consequences, particularly infectious disease-related consequences, that we can see as a consequence of environmental change," Kuritzkes said.
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