"In reservoirs with stagnant water, you can become infected with cercariosis - "itching of bathers". The risk of catching an infection is especially high if you swim in ponds and lakes that ducks, seagulls or swans have chosen, "she stressed.

The disease is caused by the larvae (cercariae) of the blood fluke, a parasite that often lives on waterfowl, the expert explained.

"Cercariae find prey in the water, bite through the skin and penetrate the surface layer. Redness and papules appear at the site of the bite, which are very itchy. In the human body, the parasite does not multiply. But, dying, it releases toxins that cause allergic dermatitis, "the doctor explained.

According to her, giardiasis is an intestinal infection, which can also be found in water bodies.

"You can get infected if you swallow water while swimming. This explains why children most often suffer from giardiasis. Once in the body, Giardia disrupts the intestines and secretes toxins that depress the nervous system. The disease usually makes itself felt only after a few weeks - the stomach begins to hurt in the navel and in the right hypochondrium, nausea appears, appetite disappears, the stool becomes irregular: diarrhea can be replaced by constipation, "the specialist said.

Another common infection in the summer is rotavirus, the interlocutor of RT warned. It can also be infected if you swallow dirty water.

"The first symptoms may appear in a day or even a week - the temperature rises, cramping abdominal pain, flatulence, diarrhea and frequent vomiting occur. The main danger of this infection is dehydration, so it is very important to observe the drinking regime and drink clean water in frequent small portions. And special solutions will help to replenish the water-salt balance, "Fileva said.

She also added that if after bathing the eyes turned red, the head hurt, and then the skin began to turn yellow, a visit to the doctor should not be delayed either.

"Such symptoms indicate the development of leptospirosis - a rather rare, but extremely dangerous bacterial infection. Those who bathe with wounds and abrasions on the skin are especially at risk of infection: through them, the bacterium enters the body and, without proper treatment, affects the liver, kidneys and lungs, "Fileva explained.

In addition, on unauthorized beaches, you can become infected with viral hepatitis A, salmonellosis, dysentery and even cholera and typhoid fever.

The sign "Swimming is prohibited" on the beach actually warns that the reservoir has not passed the sanitary and epidemiological check, the specialist explained.

Earlier, therapist Lyudmila Lapa, in an interview with RT, told what rules should be followed by vacationers in crowded resorts in order to avoid infections, as well as what medicines should be in the first-aid kit to minimize the possible consequences of "beach" diseases.