The quadrivalent flu vaccine protects for about 6 to 8 months. Immunity is usually developed in the body 2~3 weeks after vaccination.
Quadrivalent influenza vaccine has the effect of immunizing against influenza A viruses H1N1, H3N2 and influenza B viruses Victoria lineage and Yamagata lineage viruses. It is suitable for patients aged 3 years and above, especially children, the elderly, the frail, and people in areas where influenza is endemic. The general immunization effect lasts for about 6~8 months.
Patients with other symptoms such as allergy to the vaccine, period of disease seizure or uncontrolled epilepsy are not vaccinated with quadrivalent influenza vaccine. Redness, swelling, pain and hardness at the injection site may occur after vaccination, and generally no special treatment is needed. In case of severe allergic reactions such as shock, hives, etc., immediate hospitalization is required.