#Swimmers’ itch is the most common complaint after open water swimming. The itching is the result of a rash caused by flatworm larvae. These larvae are looking for a water bird, but they sometimes end up with swimmers. If the animal penetrates the skin of a human, it dies and that causes a small bump. Swimmer’s itch is bothersome, but not dangerous: the bumps disappear on their own after a few days.
Bacterium or #Blue-green algae
Infections with bacteria or blue-green algae are less common, but are more serious than swimmer’s itch. Many open waters contain faecal bacteria from the feces of birds or other aquatic animals. These bacteria can also end up in the water through other swimmers, toilet discharges from boats, untreated sewage water or agricultural manure.
The most common symptoms of bacteriological contamination are gastrointestinal infections, respiratory diseases, skin disorders, ear and eye infections.
Sometimes blue-green algae provide less swimming pleasure. The symptoms of blue-green algae infection become visible within 12 hours after swimming: headache, rash, stomach cramps, nausea, vomiting, diarrhea, fever, sore or red throat, ear pain, eye irritation, runny nose or swollen lips.
Blue-green algae can also cause stomach and intestinal disorders and damage liver cells. The symptoms last for about five days and disappear on their own. It is advisable to consult a doctor, because the symptoms of infections with blue-green algae and pathogenic bacteria are very similar.