Influenza is the flu, and you can still get it again if you have had the flu.
Influenza is a disease caused by the influenza virus. Unlike diseases such as smallpox, influenza viruses are prone to varying degrees of genomic mutation, resulting in varying degrees of alteration of hemagglutinin and neuraminidase on the surface of the influenza virus. This leads to a situation where the original immunity of the human body is completely or partially ineffective against the new subtypes created by the mutation, and recurrent influenza virus infections are likely to occur.
In addition, the rapid mutation of the surface antigen of influenza viruses makes it impossible for humans to acquire long-lasting immunity against influenza viruses, and this also makes the development of vaccines difficult, which also explains why people who have had influenza can be re-infected from another perspective.
For this reason, we need to actively prevent influenza in our daily lives. On the one hand, we should minimize contact with influenza patients, avoid crowded places, wear masks when going out, wash hands frequently and pay attention to personal hygiene. For susceptible people and those who have not yet developed the disease, we can give oseltamivir and other drugs to prevent influenza, and if necessary, we can carry out the corresponding vaccination.