Smoking does not prevent viral infections, but is harmful to the body. Tobacco contains a lot of chemicals that interfere with the functioning of the lungs and destroy the lung defense system. Smoke is mostly inhaled into the lungs when smoking, which not only increases the probability of respiratory viral infections, but also worsens the chances of infection. In addition, smoking reduces the body’s resistance and makes it more susceptible to viral attacks. In addition, the hands are in constant contact with the mouth and nose while smoking, which can increase the rate of viral infection. At the same time, when smoking can not wear a mask to effectively protect, the virus can take advantage of the opportunity to invade the body from the respiratory tract.