Influenza is a viral infection characterised by the abrupt onset of fever, sore throat, cough, headache, runny nose, muscle pain and fatigue. Influenza viruses mainly spread through droplets (coughing, sneezing or talking). The infection may also spread by direct contact with the secretions of infected persons.

Patients usually recover in two to seven days. However, it can be a serious illness to the weak and frail elders, especially those with chronic diseases, and may be complicated by bronchitis, pneumonia, and even death in the most serious cases. Serious influenza infection can also occur in healthy individuals.

Influenza can be caused by different types of viruses, with the more common strains being Influenza A H3N2 and H1N1. It occurs most commonly around January to March/April and July to August in Hong Kong and therefore it is also named as Seasonal Influenza.

Management of influenza

1. Drink adequate amount of water and consume nutritious & easily digestible food like congee with minced pork/beef, cereal, rice vermicelli etc.
2. Sufficient rest and sleep, avoid strenuous exercise.
3. Keep good indoor ventilation, like open the window, switch on exhaust fan etc.
4. Maintain good personal hygiene, cover your mouth and nose with tissue paper when sneezing or coughing. Dispose of soiled tissues into a lidded rubbish bin or flush it away through the toilet, then wash hands thoroughly.
5. Wear mask to reduce transmission of the disease by droplets. Refrain from work or attending lessons at school and avoid going to crowded area.
6. Perform home environment cleansing.

Prevention of influenza

1. Ensure good indoor ventilation and avoid going to crowded public area during peak seasons of influenza. High-risk individuals may consider wearing surgical masks if they really need to go to crowded public area.
2. Perform hand hygiene frequently, especially:
   • before touching the mouth, nose or eyes;
   • after touching public installations; or
   • when hands are contaminated by respiratory secretions after coughing or sneezing
   Wash hands with liquid soap & water and rub for at least 20 seconds. Then rinse with water and dry with tissue or hand dryer. If hand washing facilities are not available or when hands are not visibly soiled, hand cleansing with 70 to 80% alcohol-based hand-rub is also an effective way.
3. Adopt a healthy lifestyle with a balanced diet, adequate sleep, regular physical activity, no smoking & avoid drinking alcohol and stay positive to build up good immunity.
4. Influenza vaccination is an effective way of preventing complications of influenza among the high-risk groups. Consult a doctor for advice.

Influenza vaccination programme – Receive flu vaccination to prevent Influenza

According to Government Vaccination Programme, Centre for Health Protection Vaccination Office, Department of Health and Hospital Authority will provide Flu vaccinations to eligible elders (living in community or elderly homes) free of charge.

In addition, since 2003 our Elderly Health Centres will provide free influenza vaccination for eligible members. From 5 November 2018 onwards, free influenza vaccines will be provided to other Hong Kong residents aged 65 or above at 15 Elderly Health Centres, please make an appointment before injection. For more details, please visit our website: www.elderly.gov.hk. Other elders may consult their family doctor on the influenza vaccination as well.

*For details for influenza vaccination, please refer to the factsheet of Vaccination on Influenza.