Influenza A refers to an upper respiratory tract infection caused by the influenza A virus, and it is possible to get sick again after having the disease. After being infected with the influenza A virus, patients may have symptoms such as cough, fever, fatigue, loss of appetite, and poor mental health. After the virus is cured, some antibodies are produced in the body, so the patient will not get sick again for a short period of time. It is important to note that the effect of these antibodies cannot be maintained for life, and since there are many types of influenza A viruses that are prone to mutation, once one’s immunity is lowered, he or she may be re-infected and become ill again. For patients, after curing respiratory infections caused by influenza A virus, they should also continue to strengthen their protection and actively participate in physical exercise to enhance their personal immunity, which can better prevent re-infection. If you feel unwell, you should go to the hospital and consult a physician for treatment after taking personal protective measures.