Influenza Vaccine
Influenza (flu) is a disease caused by a virus. Influenza can be caused by many types of influenza viruses. The most common types in Hong Kong are H1N1 and H3N2, which are influenza A and B viruses. The virus is mainly transmitted through respiratory droplets.
Epidemic seasonal influenza virus strains may change from time to time, and the composition of seasonal influenza vaccines must be updated annually according to the circulating strains to enhance protection.
Therefore, new influenza vaccines must be given every year. Immunity develops approximately two weeks after vaccination.
In 2019/20, the Scientific Committee on Vaccine Preventable Diseases recommends that the following people in Hong Kong receive priority vaccination:
Pregnant woman
Elders living in residential care homes;
Long-term boarders living in a home for the disabled;
Persons 50 years or older;
People with long-term health problems;
Medical staff
Children from 6 months to 11 years;
Poultry industry practitioners; and
Persons engaged in pig raising or slaughtering
Epidemic seasonal influenza virus strains may change from time to time, and the composition of seasonal influenza vaccines must be updated annually according to the circulating strains to enhance protection.
Therefore, new influenza vaccines must be given every year. Immunity develops approximately two weeks after vaccination.
In 2019/20, the Scientific Committee on Vaccine Preventable Diseases recommends that the following people in Hong Kong receive priority vaccination: