The most common infectious disease associated with swimming is acute conjunctivitis, and one of the most common eye diseases in summer is called pink eye. The majority of cases occur among regular swimmers, and water from inadequately sterilized swimming pools is an important pathway that leads to the spread of the disease. It can be transmitted by contact, is highly contagious and spreads rapidly. Hands, towels and water contaminated with the virus can all be vectors of infection. If too much bleach is used in swimming pools, it can also cause eye damage. In addition to red eye, swimming may cause inflammation of the ear as the ear tends to get water in it. For those who have earwax or ear disease, dirty water staying in the ear will soften the earwax and make the ear clogged with pus, causing inflammation of the external ear canal and middle ear, etc. Gastrointestinal infections that enter through the mouth may also spread. Because people are inevitably choked when swimming, dysentery, infectious diarrhea, viral hepatitis and other germs will enter the body with the water.