The number of summer vibrion infections could increase in the coming years due to global warming, especially on the Baltic Sea coast. According to the Federal Institute for Risk Assessment (BfR), the reason for this is rising water temperatures in the oceans and estuaries, for example. They facilitate the spread of the salt-tolerant bacteria.
"Vibrions multiply from water temperatures of 20 degrees," said Eckhard Strauch, head of the BfR's consultant office for vibrions. Especially in the Baltic Sea, which has been rather cool so far, the risk could increase. Due to longer heat periods, the water temperature could climb more than 20 degrees more often in the future, so that the conditions for vibrations improved.
Favorable conditions for vibrions on the Baltic Sea
In addition, the salt concentration in the Baltic Sea is moderate. "The conditions here are particularly favorable for the two vibrion species that cause particular problems, Vibrio vulnificus and Vibrio cholerae non-O1," said Strauch. Vibrions are widespread on the entire Baltic Sea coast as far as the Baltic region. They also occur in estuaries on the North Sea.
In recent years, according to Strauch, the number of known diseases in Germany has been in the one or low double-digit range. How many people will become infected this year depends on the weather. According to the World Weather Organization (WMO), looking at the first few months, the year could bring new temperature records. The organization believes another hot summer in the northern hemisphere is possible.
Bacteria particularly dangerous for the elderly
According to the Robert Koch Institute (RKI), young and healthy adults rarely develop a vibrion infection. The bacteria are therefore particularly dangerous for older and immunocompromised people. People with previous illnesses such as diabetes, liver diseases or cancer would have an increased risk of illness and a severe course of the disease.
There have been isolated deaths in recent years. Vibrions can cause serious wound infections, symptoms include severe local pain, fever and chills. Anyone who eats seafood contaminated with vibrions that is raw or undercooked, or swallows contaminated sea water, can contract gastrointestinal disease. The infections are usually treated with antibiotics.