Rare bacterial infection caught by swimmer at Upper Cape beach

FALMOUTH – Local and state health officials confirmed on Friday a rare case of Vibrio vulnificus infection happened to someone swimming at Old Silver Beach in Falmouth.

These types of infections most often occur in at-risk individuals who are swimming in sea water with an open wound, as was reportedly the case this past weekend.

There is no advisory or closure currently in effect for Old Silver Beach.

Falmouth beaches are monitored by the Barnstable County Bathing Beach Monitoring Program for fecal bacteria as required by Massachusetts bathing beach regulations. While routine weekly sampling of Falmouth’s 52 marine and freshwater beaches has not yielded any closures due to fecal bacteria levels in 2025, there is no way to monitor bathing water for V. Vulnificus.

From the Barnstable County Department of Health and Environment:

This bacterium can cause illness in two ways: through wound infections when open cuts, scrapes, or punctures are exposed to seawater, or through consumption of raw or undercooked seafood, particularly oysters. The case in Falmouth was related to swimming with an exposed wound. In Massachusetts, V. vulnificus infections have only been linked to wound infections from swimming. There has not been a case of V. vulnificus tied to eating oysters or any kind of shellfish harvested from Massachusetts growing areas.

Vibrio vulnificus is a naturally occurring marine bacterium found in coastal and estuarine waters, especially when water temperatures are warm. Recent studies indicate vibrio cases are happening farther north, instead of just along the Gulf Coast, a trend scientists partially attribute to warming ocean temperatures. 

“Cape Cod’s beaches are an important part of our economy, culture, and community,” said Scott McGann, Health Agent for the Town of Falmouth. “By taking a few simple precautions, residents and visitors, and particularly anyone who is vulnerable or immunocompromised, can continue to enjoy them safely.”