Influenza H3N2, or influenza A H3N2, is mostly characterized by symptoms of the common cold, such as fever, cough, headache, body aches, fatigue, etc., sometimes accompanied by diarrhea and vomiting, and in severe cases can be followed by pneumonia and respiratory failure, or even death. The pathogen influenza A H3N2 virus is a subtype of influenza A virus, in which H stands for erythrocyte agglutinin and N stands for neuraminidase, which are both glycoproteins distributed on the surface of the virus, and together they determine the viral pathogenicity, infectivity and other characteristics. At present, the virus can be prevented and treated by vaccination and oral medication. Early vaccination against influenza is recommended, and medical attention should be sought if symptoms develop.