Researchers demonstrated that changes in the microbiome could leave the host susceptible to infection.
"Our data demonstrated for the first time that ocean water exposure can alter the diversity and composition of the human skin microbiome that plays an important role in immune system function, localized and systemic diseases," said Marisa Chattman Nielsen, a Ph.D. student at the University of California.
For the study, nine persons were examined who met the criteria of no sunscreen use, infrequent exposure to the ocean, no bathing within the last 12 hours, and no antibiotics during the previous six months.
The researchers swabbed the participants on the back of the calf before they entered the beach water, and again after they had air dried completely following a 10-minute swim and at six and 24 hours post-swim.
The results showed that before swimming, all individuals had different communities from one-another on their skin, but after swimming, they all had similar communities.
Vibrio species, which can cause food-borne infection usually associated with eating undercooked seafood, were detected on every participant after swimming in the ocean, and air drying, researchers said.