Killer germs spread in the Baltic Sea

Due to the climate change propagate disease-causing bacteria in the Baltic Sea . Already infected with warm summers and more people with Vibrio vulnificus, a pathogen of wound infections, diarrhoea and blood poisoning, reports an international team of researchers in the journal "Nature Climate Change." Even the closely related cholera pathogen Vibrio cholerae is on the rise. Cause of the spread of the bacteria is the sea water becoming warmer.

For every degree that warm it in the Baltic Sea in the future, will increase the number of cases nearly doubled. Affected by this increase in risk of infection are especially densely populated central and southern coasts of the Baltic Sea, the scientists warn. Apart from Denmark and southern Sweden is offered, including Germany and Poland.

Life-threatening fever and blood poisoning

"This is one of the first evidence that climate change can penetrate Vibrio pathogens in temperate regions," Craig Baker-Austin signed by the Centre for Environment, Fisheries and Aquaculture Science in Weymouth and his British colleagues. This shows that the man-made warming begin to change the distribution of infectious diseases.

In addition to the cholera pathogen Vibrio cholerae in warm sea water is found mainly the bacterium Vibrio vulnificus. It causes diarrhea in healthy people, vomiting and stomachache. Get it on wounds or the bloodstream, the immune system of patients weakened, it can also trigger life-threatening fever and blood poisoning.

Baltic Sea heats up in record time

The bacteria of the Vibrio group usually prefer water of at least 15 degrees Celsius and low salinities. For a long time it was too cold in many parts of the Baltic Sea, so that the pathogens could not survive in the long run. Due to climate change, this has changed. "Between 1982 and 2007, water temperatures in the Baltic Sea has risen by 1.35 degrees Celsius - that's seven times more than the global average," say the researchers. The Baltic Sea is thus the fastest warming marine ecosystem in general.

The warmer water has the expectant Baltic pathogens better and better living conditions. They can multiply quickly, and their pathogenic effect on the increase, as the researchers report. During the extremely hot summer of 1994, 2003 and 2006 it was on the Baltic coast already been numerous reports of infected wounds and possibly even cases of cholera. In 2006 alone, 67 people infected with bathing or water sports with Vibrio pathogens, some died.

30 million people are directly threatened

By the year 2050 will increase the number of Vibrio infections clearly if the warming of the Baltic Sea would progress further, the researchers say. Each degree water temperature increases the more infections the number of 1.93-fold. Disease cases are then no longer be expected only in extremely hot summers. In addition, the risk area will continue to spread northward. Then could also metropolitan areas such as Stockholm and St. Petersburg may be jeopardized. "More than 30 million people live less than 50 kilometres from the Baltic Sea,". These people carry an increasing risk of becoming infected through open wounds, contaminated seafood, but also swallowed water with the vibrio bacteria.

For their study, the researchers analyzed the recent cases of infection by water-living bacteria in the Baltic region. On the basis of current climate predictions, they also determined, as is the risk of infection to develop by 2050.