Experts believe a new Covid surge in South Africa could offer clues to the pandemic’s next chapter.
Following a decline in cases after an “Omicron-fuelled, pandemic peak in December”, the number of infections there has tripled over the past week, and hospitalisations have increased, reported The New York Times (NYT).
The new spike, which has prompted fears of a fifth wave in the country, is powered by BA.4 and BA.5, two sub-variants of the Omicron family. An expert said this might point to a period of new sub-variants, rather than fresh variants.
“What we are seeing now, or at least maybe the first signs, is not completely new variants emerging, but current variants are starting to create lineages of themselves,” Tulio de Oliveira, director of South Africa’s KwaZulu-Natal Research and Innovation Sequencing Platform, told the NYT.
Scientists said the body’s ability to fight the new sub-variants depends on your vaccination status more than on whether you’ve been infected in the past. In unvaccinated people, BA.4 and BA.5 evade natural defences produced from infection with the original Omicron variant, known as BA.1.
Meanwhile, experts are still establishing whether the new wave in South Africa creates milder or more severe illness. They say it is unclear if the two sub-variants could surge elsewhere in the world.
“We’re at an awkward global moment where the past can’t really predict the future,” said Dr Kavita Patel, a primary care physician who led the pandemic preparedness response for the swine flu virus.
However, writing on Twitter, Professor Tom Wenseleers of KU Leuven, said the situation in South Africa “gives a good idea of what the endemic equilibrium will look like: a significant wave every six months with significant mortality and morbidity”.
In the UK, government data on the most dominant variants showed there were just six cases of BA.4 and three of BA.5. The most prevalent variants in new cases were the original BA.1 Omicron variant and BA.2.
Professor Christina Pagel, of University College London, told The Guardian it is “very likely” the new sub-variants will become dominant here, adding at best this would lead to a small wave and at worst a similar experience seen with BA.1 and BA.2.
Meanwhile, UK experts have predicted that within a year we might talk about “catching a Covid” just as we do with the common cold.
The i news site reported that, as people build up immunity from vaccines and previous infections, the virus has weakened to become more cold-like in recent weeks.
Professor Karl Friston, a virus modeller at University College London, said “the probability of dying when infected – or developing an acute respiratory distress syndrome – continues to decline with successive viral mutations”.
However, Covid remains deadly for some people and there is still a risk that immunity levels will deteriorate and that a much more deadly new variant will emerge.