While scientists study the new variant, based on what they’ve already observed, the current vaccines are expected to protect against severe disease, says Professor Salim Abdool Karim.
The emergence of new Covid-19 variants over the last several months have raised questions about when the pandemic will end. After the discovery of a new variant of concern (VoC) in South Africa last week, there are questions around whether the current vaccines will remain protective against the disease. The variant, named Omicron, has already been detected in 11 other countries, as of 28 November. « Our public health interventions all work, [but] the area that has created the concern and this global overreaction is that we’re not sure about whether the current vaccines will protect against this new variant, » said epidemiologist Professor Salim Abdool Karim during a media briefing on Monday. Based on what scientists know about the other four VoCs – Alpha, Beta, Gamma and Delta – and how these variants have reacted to vaccine immunity, Abdool Karim said experts expect the vaccines will continue to offer strong protection against severe disease caused by Omicron. Antibodies, T cells « Protection of the vaccines is likely to remain strong. I don’t know this definitively – the studies are being done – but based on what we know, we can expect that… the vaccines should hold well in preventing hospitalisation and severe disease, » said Abdool Karim. This is because the prevention of severe disease depends more on one arm of the immune system, known as T-cell immunity, and less on antibodies, another arm of the immune system. « So even if there’s some escape from antibodies, it’s very hard to escape T-cell immunity, » he said. Global data on the vaccines also suggest that, even over time, the protection offered by the vaccines against severe disease, caused by the different variants, including Delta, remains effective, said Abdool Karim. This is the case for both the Pfizer-BioNTech and J&J vaccine. « They tend to do quite well in protecting against severe disease [and] that’s our big concern with this disease – we don’t want to end up with a situation where our hospitals are overwhelmed, » he said.
