Those at risk of developing severe Covid-19 complications have been advised to take additional precautions after the South African Medical Research Council noted sharp increases in the concentrations of SARS-CoV-2 RNA in several wastewater treatment plants.

This includes plants in the city of Cape Town, as well as in the Western Cape towns of De Doorns, Rawsonville and Worcester during the past week.

President and CEO of the SAMRC Professor Glenda Gray says the increase coincides with an increase in the proportion of positive COVID-19 tests recently reported by the National Institute for Communicable Diseases.

It’s important to note that the fragments of SARS-CoV-2 RNA in wastewater are not the live, infectious virus. There is no evidence that COVID-19, no matter the variant, can be contracted from wastewater or water, including drinking water.

For the past two years the SAMRC has been operating a surveillance programme for SARS-CoV-2 RNA in more than 80 wastewater treatment plants across 6 provinces in South Africa.

This has been undertaken to help track the pandemic in the country. Over the past week the SAMRC Wastewater Surveillance team has measured concentrations of SARS-CoV-2 RNA in Cape Town and parts of the Western Cape, that have not been observed for many months.

Professor Angela Mathee, a member of the SAMRC Wastewater Surveillance team, said that at this stage similar increases in SARS-CoV-2 RNA concentrations in wastewater have not been observed in the remaining five provinces (Gauteng, northern KZN, Limpopo, Eastern Cape, Free State) in the SAMRC programme.

“We will be paying close attention to next week’s results ascertain further changes, should they occur,” said Mathee.

“Over the next few weeks, it may be prudent for those at risk to revert to basic protective measures, such as avoiding, or wearing masks in, crowded indoor spaces or when caring for people who are ill, being fastidious about hand hygiene and keeping up to date with COVID-19 vaccinations or booster shots,” she added.