Hong Kong experiences peak influenza seasons between January and March, in April, and again from July to August. The Centre for Health Protection has stated that this year's influenza epidemic is more active than in the past three years. The overall rate of hospital admissions to public hospitals due to influenza has shown an upward trend. The elderly, children, and individuals with chronic illnesses are particularly high-risk groups and should get vaccinated against influenza as soon as possible to help prevent infection.
Flu is a common respiratory illness caused by influenza viruses.
Flu is an infectious disease that affects the respiratory system, primarily transmitted through droplets produced when coughing or sneezing, or by touching infected objects. The virus can survive on surfaces for up to twenty-four hours.
Seasonal flu is generally divided into types A, B and C. Among these, influenza A (H1N1) virus has now become one of the global seasonal influenza virus strains. The types of flu that are common in Hong Kong are mostly types A and B. Infections present with symptoms such as fever, cough, runny nose, headache, body aches, vomiting, and diarrhoea. It can potentially spread to the lungs, and in severe cases, may even lead to death.
Why is it necessary to get a flu jab every year?
As influenza viruses are RNA viruses, they mutate faster than DNA viruses. The viral strains differ every year and every season, and the mutations occur with no discernible pattern. Therefore, every year, epidemiologists from the World Health Organization collect samples globally to decide which viral strains to use to produce related vaccines. This explains why influenza vaccines need to be administered annually; otherwise, they cannot reduce the risk of flu infection.
The government provides free/subsidised flu vaccinations for adults aged 50 and over.
From April 2023, Hong Kong residents aged 50 or above are eligible for a subsidy of $260 per dose of seasonal influenza vaccine, which can be used at registered private doctor clinics participating in the scheme.
In Hong Kong, flu vaccines are divided into two types of inactivated flu vaccines: "trivalent" and "quadrivalent". According to the Centre for Health Protection, the "trivalent" vaccine is expected to prevent most flu cases, while the "quadrivalent" vaccine offers additional protection against influenza B. There are also injectable and nasal spray types, and doctors will decide which vaccine to use based on your individual circumstances.
*Information provided by GlaxoSmithKline (GSK)
