Whether influenza A in children is contagious to adults depends on the individual’s physical condition, and is easily transmitted when immunity is relatively weak; if one’s own immunity is relatively strong, the rate of transmission is relatively low. If an adult’s immunity is relatively weak, and the child has not taken proper precautions after contracting Influenza A and is often in close contact, he or she may also be infected, mainly through droplets via the respiratory tract. If the resistance of adults is stronger and they are not prone to colds and diseases, even if they have contact with infected people, they will not be easily infected and the probability of infection will be significantly reduced. In order to prevent Influenza A, it is recommended to wash hands frequently, open windows and ventilate the room, and disinfect the room regularly; and keep a certain distance from the infected child and avoid talking in close proximity. After being infected with Influenza A, it may not be detected immediately because the disease has an incubation period during which there are no obvious symptoms. If you suspect that you are suffering from Influenza A, you should seek medical advice promptly.