Seasonal Flu Vaccine
The flu, also known as influenza, is an acute illness affecting the respiratory system which originates from influenza viruses. In Hong Kong, H1N1 and H3N2 subtypes of influenza A virus along with influenza B virus are observed most frequently in January to March/April and July to August. Symptoms such as fever, sore throat, coughing, runny nose, headache, muscle pain and weariness usually appear due to this condition.
The virus is highly contagious and primarily transmitted through respiratory droplets and close contact. To prevent infection, it’s important to practice good personal hygiene habits such as frequent hand washing and receiving the flu vaccine.
What are the symptoms of Influenza?
Flu manifests through the typical symptoms of a sore throat, cough, runny nose, fever, fatigue and gastrointestinal distress such as vomiting or diarrhea. Most healthy individuals will recuperate within 1 week but those with severe symptoms or weakened immunity may experience them for longer periods.
How to prevent Influenza?
The occurrence of the seasonal flu could be averted through:
Get flu vaccination
Getting a flu shot is an effective measure to avoid contracting the flu. As seasonal influenza strains have the potential to mutate, annual updates are made to the components of the vaccine. Therefore, it’s advisable to receive an annual flu shot for optimal protection against contracting this illness.
Maintain personal and environmental hygiene
Regularly washing one’s hands is an effective measure for controlling the transmission of the virus, especially after being in communal spaces or coming into contact with a person infected by it. Furthermore, consistently sanitizing commonly used items such as mobile devices, furniture, and toys can effectively impede the spread of infectious diseases.
Maintain healthy lifestyle
Maintaining a healthy lifestyle can aid in enhancing the immune system, which includes consuming sufficient servings of fresh vegetables and fruits, engaging in regular physical activity, getting proper rest and more.
Quit or reduce drinking and smoking
Consumption of alcohol and tobacco can compromise the immune system, thereby increasing vulnerability to flu infection. As a result, individuals should either abstain from or limit their alcohol and tobacco intake for better health outcomes.
Get the Vaccine, Prevent Influenza
Receiving the flu vaccine is an efficacious method of protecting against influenza infection. Listed below are reasons why obtaining the flu vaccine is significant:
Prevent influenza infection
The influenza vaccine is a highly effective method for preventing seasonal flu and its associated complications. It can also significantly decrease the occurrence of hospitalizations and fatalities related to influenza infections.
Avoid severe symptoms
Receiving a flu vaccine can help prevent the development of severe symptoms and decrease the likelihood of complications, including but not limited to pneumonia, heart disease, encephalitis.
Protect high-risk groups
Individuals at a higher risk of severe influenza and its related complications are the elderly, pregnant women, infants, and those with suppressed immunity. To safeguard these vulnerable groups from flu transmission, healthy individuals can opt for influenza vaccination as it offers significant protection against the virus.
Virus transmission control
Receiving the flu shot has the potential to decrease the transmission of influenza, which could effectively manage its prevalence within the community.
Who needs to get Influenza vaccination?
The influenza vaccine is both safe and efficient, making it a recommended practice for all individuals six months of age or older.
Furthermore, certain groups of people are at a higher risk of spreading the virus or experiencing severe symptoms themselves. These priority groups are strongly recommended to get vaccinated against influenza:
Healthcare workers (including care workers in Residential Care Homes for the Elderly [RCHE] and Residential Care Homes for Persons with Disabilities [RCHD])
Persons aged 50 years or above
Pregnant women
Residents of Residential Care Homes (such as RCHE or RCHD)
Persons with chronic medical problems, such as people with chronic cardiovascular, metabolic or kidney diseases, obesity, weakened immunity, etc.
Children aged 6 months to 11 years
- Poultry workers
Pig farmers and pig-slaughtering industry personnel
- Secondary school student
Injected Flu Vaccine
Inactivated influenza vaccine (IIV) through injection
The IIV is formulated with the viruses that have been inactivated (killed) during the manufacturing process, triggering the immune responses and increasing immunity towards Influenza.
Humansa provides Influenza vaccination
Composition of Influenza Vaccine
The egg-based quadrivalent influenza vaccine recommended by the World Health Organization (WHO) for the 2025-26 season contain the following:
- an A/Victoria/4897/2022 (H1N1)pdm09-like virus
- an A/Croatia/10136RV/2023 (H3N2)-like virus
- a B/Austria/1359417/2021(B/Victoria lineage)-like virus
- a B/Phuket/3073/2013(B/Yamagata lineage)-like virus
Flu Vaccine (Injection Shot)
Suitable for people aged 6 or above
FAQs of Influenza vaccine
Receiving a flu shot is typically considered safe, although there may be some adverse reactions like tenderness and inflammation at the injection site, fever, headache or other related symptoms. It is important to note that most individuals do not experience these symptoms and they are typically temporary as well as mild in nature.
Over time, the protection acquired from vaccination diminishes and may eventually provide no safeguard against seasonal influenza. Since seasonal influenza strains may vary over time, the formulation of the vaccination is updated annually; as a result, it is highly advised to receive flu shots every year.
The above information is for reference only and shall not be considered as medical advice. Please consult with your doctor or healthcare provider for further enquiries.