Despite standards to maintain clean swimming areas, coastal waters in high-income countries are likely to house microbes that increase swimmers' risk of stomach aches, ear infections and diarrhea, according to a review of more than 40 previous studies published in International Journal of Epidemiology.
The researchers examined illness rates among swimmers and beachgoers who stayed dry in a review of nearly six decades' worth of studies in high-income, developed countries, including the U.S., U.K. and Australia. The review indicated people exposed to seawater were 86 percent more likely to experience any type of illness and more than twice as likely to have an earache. The review found gastrointestinal illnesses were less commonly reported, with only an increased risk of 29 percent among bathers.
"There have been lots of studies looking at the links between bathing in the sea and experiencing a variety of symptoms of ill health," lead author Dr. Anne Leonard told Reuters. "These have been summarized mostly for gastrointestinal complaints such as diarrhea and vomiting."
However, these findings do not necessarily mean people need to stay away from seawater, Dr. Leonard added. "There are many health benefits from swimming in the sea, such as improved physical fitness and an increased sense of wellbeing and the above ailments are likely to be minor in the majority of bathers, probably resolving without medical intervention in a few days."