Research has shown that the risk of infection is the highest during and the day after rain, so it is not recommended that you go swimming in a pool after rain. If the chance of infection is so great, then what about the water in rivers? The concentration of microorganisms in rivers is greater than that in pools, so it is more dangerous to swim in rivers.

Silky Terrier Dog Breed Playing Aro... Silky Terrier Dog Breed Playing Around

As for the concentration of microorganisms, it is generally believed that bacteria and viruses are more prevalent in rivers than pools. This is because water currents in rivers are stronger, not only carrying infectious agents but also stirring up sediment at the bottom of rivers, which leads to an increase in the number of bacteria. Besides that, human activities have led to an increase in the number of microorganisms. For example, when using rivers as a toilet, more bacteria will be discharged into the water; if people are found polluting the river, then there will be many microorganisms in the river.

This is not to say that you can’t swim in rivers at all, you just shouldn’t do so after heavy rain. The water in the river will be heavily contaminated by microorganisms, especially during heavy rainfall. You may not feel any discomfort when swimming, but you will still be infected with bacteria and viruses that can make you sick later on.

If you are afraid of catching a cold after swimming in rivers, then there is nothing to worry about; most of the bacteria and viruses will be washed away after many days.

Moreover, there it is a little bit untrue that bacteria and viruses can spread from your nose to brain through the skull, they have been proved to be blocked by the nasal mucous membrane.

One of the most dangerous microorganisms in rivers is a kind of Gammapolilococcus bacteria, which attacks people with low immunity at night. During day time, the number of bacteria in rivers is decreasing with the sunlight; however, at night it will join forces with other germs to make you sick.