Skin rash after swimming in Greifenburg lake: Municipality provides information on cercarial dermatitis

Background: What are cercariae?

According to the authorities, the background is the life cycle of certain parasites: The larvae, known as cercariae, normally infect water birds, aquatic mammals and water snails as hosts. „Die Larven können sich in warmen Gewässern fälschlicherweise aber auch in die Haut von Menschen einbohren und eine juckende allergische Hautreaktion auslösen“, the Ministry states. Since humans are so-called accidental hosts, the pathogens do not penetrate deeper into the body and die in the skin – a finding that is considered by experts to be harmless, if very unpleasant.

The ongoing heat is currently driving particularly large numbers of people to local waters in search of refreshment. This also increases the likelihood of contact with the parasites, which are found in particularly large numbers in warm water.

The municipality of Greifenburg emphasizes that the lake is a natural bathing facility: „der Badesee Greifenburg ist eine Naturbadeanlage“. At the same time, it points out that water quality is regularly monitored. „Die Wasserqualität unseres Badesees ist wird durch das Amt der Kärntner Landesregierung regelmäßig geprüft und die Werte sind allesamt vorbildlich!“, the municipality announced. The occurrence of cercariae has „keinerlei Auswirkungen auf die Qualität des Wasser“, it added.

Water quality and municipal responsibility

The municipality also acknowledges that it has no influence on the settlement of water birds at the lake. „Auf das Ansiedeln von Wasservögeln haben wir keinen Einfluss“, the administration explained. It addressed an urgent appeal to swimmers: „unsere Badegäste bitten wir jedoch eindringlich, Enten nicht noch zusätzlich anzulocken“. Anyone who feeds water birds only attracts the animals more into the bathing area.

For prevention, the municipality recommends several measures: „Das Verwenden von wasserfesten Sonnenschutzmitteln, Abduschen nach dem Badegang und Abtrocknen nach der Dusche helfen, Badedermatits zu vermeiden.“ Changing wet swimwear can also reduce the risk, as can thoroughly showering and drying off immediately after swimming to remove cercariae that have not yet penetrated the skin.

Prevention and behavior in case of symptoms

According to the Ministry and medical authorities, anyone who has already developed symptoms should use cooling lotions or gels. A visit to a doctor is recommended if there are signs of an additional bacterial infection. In principle, the infestation is considered harmless, even though the itching is described as very unpleasant.

The municipality also clarifies that the Greifenburg bathing lake is located in Carinthia and is a popular destination during the summer months. With regard to the ongoing heat wave, it asks visitors to observe the precautionary measures mentioned in order to avoid infection with cercarial dermatitis as far as possible.

Overall, from the municipality's perspective, the situation is a known side effect of swimming in natural waters in summer. It warns against panic, emphasizes the good water quality and at the same time asks for prudent behavior – particularly with regard to water birds.

The incidents at Greifenburg lake are part of a series of similar cases that are repeatedly reported from various federal states during hot summers. Experts see cercarial dermatitis as a temporary skin reaction that usually subsides without consequences.