What Did the 2022 Surveillance Reveal About Respiratory Illnesses in South Africa?

Respiratory viruses are known for causing illnesses in the respiratory system, with symptoms often affecting both the upper and lower respiratory tracts. Viruses like COVID-19, flu, and RSV are common during the autumn and winter seasons, leading to hospitalizations and deaths.

Symptoms of respiratory viruses can range from fever, cough, and fatigue to sore throat, vomiting, and a loss of taste or smell. In severe cases, they may cause pneumonia or other serious lung infections.

Certain groups face a higher risk of severe illness from respiratory infections. These include older adults, young children, people with weakened immune systems, those with disabilities, and pregnant or recently pregnant individuals due to various health vulnerabilities.

Respiratory disease surveillance systems help monitor illness trends, track seasonal changes, and identify at-risk groups. These systems play a key role in spotting severe infections and guiding public health responses. When a sentinel surveillance program works well, it can detect and manage respiratory diseases, while also measuring the effectiveness of new prevention strategies.

The National Institute for Communicable Diseases (NICD) runs multiple surveillance programmes for respiratory illnesses, including the Pneumonia Surveillance Programme (PSP) and two influenza-like illness (ILI) programmes. These programmes monitor influenza, RSV, Bordetella pertussis, and SARS-CoV-2 through respiratory samples tested at sentinel sites.

This report provides insight into the changing epidemiology of respiratory pathogens, including SARS-CoV-2, after the ease of COVID-19 lockdown measures and provides data that could be used to assist stakeholders and policymakers in making informed decisions on implementing different or new prevention and control strategies.

Materials and Methods

The surveillance programmes for respiratory illnesses are used to track respiratory diseases in hospitals and clinics across several provinces in South Africa. Healthcare workers screen patients for conditions like COVID-19, influenza, and pertussis. Eligible patients have nasal swabs collected for testing. Data is stored in NICD databases, and testing for viruses like influenza, RSV, and SARS-CoV-2 is done using RT-PCR assays. SARS-CoV-2–positive samples undergo further sequencing, and influenza A is subtyped.

Results 

During the 2022 influenza season, which ran from April to October, there were two main peaks of activity. Influenza was found in about 33% of tested samples, with the most common types being A(H1N1), A(H3N2), and B/Victoria. The RSV season occurred earlier in the year, showing higher impact among young children. RSV was detected in 11% of all tested specimens, mainly in children under five. SARS-CoV-2 was also monitored, with Omicron being the dominant variant. Additionally, a few cases of whooping cough were reported, mostly in the Western Cape province.

For a more in-depth look into this captivating study, download the full article below.