As swimming in Southern Europe becomes increasingly popular, holidaymakers should be aware of the rising threat posed by parasitic flatworms. These harmful creatures carry schistosomiasis, a disease that can cause severe health issues. So be cautious before diving into a Spanish lake this summer.
Research from Belgium’s KU Leuven, the Royal Museum for Central Africa, and the University of Copenhagen has highlighted that the emergence of parasitic flatworms in Southern Europe is largely attributed to climate change. These worms inhabit freshwater snails, and the warming climate in Southern Europe is becoming more favourable for these snails. Previously thriving in warm African countries, these parasites are now increasingly found in parts of Greece, Italy, Spain, France, and Portugal, posing significant health risks to those in contact with them.
Climate change and parasitic infections
The researchers explain the infection cycle: “Both the snail, parasite, and human are needed to complete the infection cycle. Currently, travellers bringing the parasite from Africa to Europe are not a major problem, but with climate change, all three elements could thrive in the European climate, leading to further spread of the infection.” Freshwater snails can easily adapt to new conditions, making it simple for them to colonise new areas like Europe. The parasitic flatworms on these snails are thus becoming an ever-growing problem.
Health risks of schistosomiasis
The parasitic flatworm affects people who swim in contaminated freshwater bodies such as rivers, ponds, and lakes. Infection occurs upon contact with water containing the parasite, which penetrates the skin and enters the body. Annually, over 200 million infections are reported worldwide, predominantly in African countries. However,returning travellers also bring schistosomiasis to their countries each year.
Infections can lead to symptoms such as itching, rashes, fever, and chills. In severe, untreated cases, risks include infertility and bladder cancer. Symptoms may remain unnoticed for a long time and vary in severity among individuals.
No preventive vaccine
Currently, there is no preventive vaccine for schistosomiasis. To avoid infection, it is advisable to avoid natural freshwater bodies known to harbour the disease. Cooling off in a chlorinated swimming pool is a safer alternative, as the snails cannot survive in chlorinated water.
Stay alert
While it is unlikely that parasitic flatworms will become widespread in Southern Europe this summer, it is important for travellers to remain vigilant. Returning holidaymakers should be more alert to the symptoms. This also applies to general practitioners who may not immediately link symptoms to schistosomiasis if tourists have not travelled outside Europe, leading to potential misdiagnoses.