Antibodies are produced after recovery from influenza, but such antibodies have a limited preventive effect. In case of accidental infection with influenza, antibodies can be formed in the body after full recovery. Influenza is caused by an infection with the influenza virus. After treatment, the virus stimulates the body’s immune system to form antibodies against the influenza virus. However, the protective effect of such antibodies is limited. On the one hand, the titer and number of antibodies will decrease over time, resulting in poorer and poorer protection; on the other hand, the influenza virus is constantly changing, and some of the genetic information is different, which can lead to the loss of the protective effect of the original antibodies. Therefore, it is recommended to get vaccinated against influenza as early as possible as an effective preventive measure against influenza.