Dr Yeung Ho Hong 楊浩康 醫生 health-prevention-info

Quadrivalent influenza vaccine (流感疫苗)

Dr Yeung Ho Hong ( 楊浩康 醫生 ) 2021-10-15

Quadrivalent influenza vaccine (流感疫苗)


The annual influenza season is coming again, and it’s time to have influenza vaccine to protect yourself and your family. Influenza virus strains may change from time to time, and the annual influenza vaccine components will be updated according to the prevailing virus strains. Therefore, it is necessary for us to get the flu vaccine every year.

The quadrivalent influenza vaccine (Northern Hemisphere winter virus) recommended by the World Health Organization for inoculation at 2021/2022 includes:

  • an A/Victoria/2570/2019 (H1N1) pdm09-like virus
  • an A/Cambodia/e0826360/2020 (H3N2)-like virus
  • a B/Washington/02/2019- like virus (B/Victoria lineage)
  • a B/Phuket/3073/2013-like virus (B/Yamagata lineage)

The quadrivalent influenza vaccine can be divided into 2 types: injection and nasal spray. The injectable quadrivalent flu vaccine is suitable for people over 6 months old, and the nasal spray quadrivalent flu vaccine is suitable for people aged 2-49. This year "Vaccination Subsidy Scheme" has also been launched. Children from 6 months to 11 years old, Hong Kong residents aged 50 or above, pregnant women, disability allowance recipients can receive government funding for influenza vaccination. If you want to know more about the latest " Vaccination Subsidy Scheme ", you can visit the website of the Centre for Health Protection.

Many people who want to get vaccinated ask if they can get the flu vaccine and the new Covid-19 vaccine at the same time. There is no known interaction between the flu vaccine and the new Covid-19 vaccine. The Scientific Committee recommends that there should be a gap of at least 14 days between the new Covid-19 vaccine and other vaccines. If you are infected with COVID-19 and influenza at the same time, serious complications and mortality will increase, and influenza vaccine can reduce the rate of hospitalization and shorten the length of hospitalization.