If it doesn't rain and snow for a long time, why are there fewer people who get sick when it rains and snows?

Your statement that "it snows in winter can reduce diseases" is very popular among the people in China, and it has certain scientific basis.

The reason why the incidence of respiratory diseases is relatively high this year has little to do with snowfall. If it doesn't snow for a long time, the air in winter will be cold and dry, which will make the content of dust and bacteria in the air higher and easily induce respiratory diseases. After snowing, the dust in the air will be obviously reduced, and the bacteria will also be reduced. Relatively humid air will also make our respiratory tract less sick.

For people who are prone to respiratory diseases such as the elderly, we should first pay attention to keeping warm and wearing thick clothes when going out to avoid cold air stimulating the respiratory tract; Second, for people with respiratory diseases, because the weather is dry and dusty, they should do some protection when going out, such as wearing a mask to reduce the inhalation of dust and bacteria; The third is to go out as little as possible, and you can properly open the window for ventilation; Fourth, if the air is dry, it is best to breathe more through the nose, less through the mouth, and use a humidifier at night.