Stomach bugs are being caused by a new bacteria group that has emerged in northern Europe due to manmade climate change, according to researchers.
A paper written by a group of international experts offers some of the first firm evidence that the warming patterns of the Baltic Sea have coincided with the emergence of Vibrio infections in the north of the continent.
Vibrios is a group of bacteria which usually grow in warm and tropical marine environments.
It can cause various infections in humans, ranging from cholera to gastroenteritis-like symptoms from eating raw or undercooked shellfish or from exposure to seawater.
A team of scientists from institutions in Britain, Finland, Spain and the United States examined sea surface temperature records and satellite data, as well as statistics on Vibrio cases in the Baltic.
And their paper, published in the journal Nature Climate Change , reveals they found the number and distribution of cases in the Baltic Sea area was strongly linked to peaks in sea surface temperatures.
Each year the temperature rose one degree - while the number of Vibrio cases increased almost 200%.
Craig Baker-Austin, from the UK-based Centre for Environment, Fisheries and Aquaculture Science, one of the authors of the study, said: "The big apparent increases that we've seen in cases during heat wave years... tend to indicate that climate change is indeed driving infections.
"Certainly the chances of getting a vibrio infection are considered to be relatively low, and more research is focused on areas where these diseases are endemic or at least more common."
Climate studies show that rising greenhouse gas emissions made global average surface temperatures increase by about 0.17 degrees Celsius each decade from 1980 to 2010.
The Vibrio study focused on the Baltic Sea in particular because it warmed at an unprecedented rate of 0.063 to 0.078 degrees Celsius a year from 1982 to 2010, or 6.3 to 7.8 degrees a century.
"[It] represents, to our knowledge, the fastest warming marine ecosystem examined so far anywhere on Earth," the paper said.