The 2019 South African influenza season, which started towards the end of April, is ongoing. Transmission of influenza has reached high levels in the Viral Watch programme, as determined by the Moving Epidemic Method (a sequential analysis using the R Language, available here. To date the majority (357/390, 92%) of influenza-positive samples for this season, detected by three surveillance programmes, have been identified as influenza A(H3N2). Download the latest NICD influenza surveillance report
There has been a marked increase in cases of influenza in the community as well as people seeking care for influenza-like illness at health care facilities.
Influenza cases in schools
There have been a number of clusters of influenza cases in schools, which is not uncommon as children are important transmitters of influenza. Influenza in school-age children rarely causes severe complications unless they have underlying conditions. If a school-going child has symptoms of influenza (sudden onset of cough, fever, body pain with or without other respiratory symptoms) they should remain at home, rest and take plenty of fluids. If danger signs such as chest pain or shortness of breath are noted, medical attention should be sought. Read further information on influenza, including frequently asked questions here.
Influenza vaccination
Influenza vaccine remains the primary means for preventing seasonal influenza infection. Although we are in the midst of the influenza season, it is never too late to vaccinate, as most years more than one strain of influenza circulates during the season. The annual seasonal influenza vaccine contains strains corresponding antigenically as closely as possible to the 3 seasonal influenza strains prevalent in human populations: influenza A(H1N1)pdm09, influenza A(H3N2) and influenza B. A protective antibody response takes about 2 weeks to develop.
Groups at increased risk of severe complications of influenza include pregnant women, HIV-infected people, the elderly (65 years and older), people with chronic illnesses or conditions like diabetes, lung disease, tuberculosis, heart disease, renal disease and obesity and children less than 5 years old. These groups should be prioritized to receive the vaccine.
Number of positive samples by influenza types and subtypes and detection rate* from the Viral Watch programme, South Africa, 2019