The National Institute for Communicable Diseases has urged the public to get vaccinated against the influenza virus as flu season in South Africa has arrived earlier than usual.
The NICD says the 2026 influenza season started in the week of 9 March. The flu season is declared when the rate from the Institute’s sentinel surveillance exceeds the defined level for the season to start and is sustained for two consecutive weeks.
While this year’s season has started earlier than in recent years, it is similar to 2025, when the season started in the week of 24 March.
The 2026 respiratory syncytial virus (RSV) season also started in the week of 9 March 2026.
“The fact that both the flu and RSV seasons are starting at the same time means clinicians could potentially see a high burden of patients with respiratory illness in medical facilities in the coming weeks.”
Influenza A(H3N2), A(H1N1)pdm09 and influenza B are common seasonal influenza strains in humans.
A new strain of influenza A, specifically a novel variant of subclade K of the A(H3N2) virus, which caused severe, early-onset activity in the Northern Hemisphere in late 2025, is expected to continue circulating in the Southern Hemisphere’s winter season.
The majority of people with influenza present with mild illness, which usually resolves within three to seven days. However, influenza may cause severe illness, leading to hospitalisation or possibly death, especially among those at risk of severe illness or complications.
Influenza vaccination is recommended to protect against infection and severe illness.
The NICD says the vaccine should be administered before the start of the influenza season, as it takes about two weeks for an adequate immune response to develop following vaccination.
However, it is not too late to vaccinate once the season has begun.
The vaccine is now available in pharmacies.
“The early start to the season means that this year, the vaccine is only becoming available as the season is getting started, so members of the public who fall into groups at high risk for severe influenza are urged to get their vaccines as soon as possible.”
High-risk groups include:
- Pregnant women
- Individuals living with HIV
- Those with chronic conditions such as diabetes, lung disease, tuberculosis, heart disease, renal disease, and obesity
- Individuals older than 65
- Children under two years old (the flu vaccine can only be given to children from 6 months of age)
These groups should be encouraged to seek medical help early if they develop respiratory symptoms which are not resolving.
RSV is the leading cause of bronchiolitis and lower respiratory tract infections in young children and can lead to severe illness in infants. It is highly contagious, primarily spreading through respiratory droplets.
The RSV season typically begins in mid-February, with the onset ranging from late January to late February, usually preceding the influenza season. This year, the RSV season has started later than usual.
The flu vaccine does not protect against RSV.
To reduce the spread of flu and RSV in your community, remember to:
- Wash your hands often
- Cover coughs and sneezes with your elbow or a tissue
- Avoid close contact with people who are sick
- Stay home if you are feeling unwell.
