South Africa could be entering its fifth wave of Covid-19 infections according to some analysts who point to two things that have caught scientists by surprise: the timing of the wave and what is driving it.
Health minister Joe Phaahla said on Friday that after a period of “stability with low infections” there is a “sharp uptick”, especially in Gauteng, KwaZulu-Natal and the Western Cape, which collectively account for more than 85% of all cases.
The positivity rate is at 17%, and in a single day this week there were more than 6,000 confirmed infections. Active cases have breached 39,000 — about 3.6 times up on their level two weeks ago.
However, there are only 2,000 hospital admissions and 192 people in intensive care.
Over the past two weeks, there has been a 137% increase in new cases, said the minister, but hospitalisations remain low and deaths have not increased.
What has caught scientists off guard is that the wave has arrived earlier than expected and is being driven by a subvariant of Omicron rather than a new variant.
“We were expecting this resurgence in mid-May or early June but it has come sooner,” said Phaahla, adding one possible factor is that Easter, Ramadan and Passover coincided.
“It was believed the new wave would be driven by a new variant but at this stage that is not the case. There are changes in Omicron itself but these are sublineages,” said Phaahla.
“There are changes, but they are not enough to be defined as a new variant of concern. However, it is important to note we are at great risk as we enter winter.”
Earlier this week, former ministerial advisory committee head Prof Salim Abdool Karim said South Africa was in a fifth wave according to the definition of more than five cases per 100,000 people.
However, Phaahla said: “It is also argued one can say we’re in a fifth wave if we have more than 63,000 cases per day on a sustained level. We will only know after another seven days if this is a sporadic uptick or a new wave.”
According to Dr Waasila Jassat, a public health specialist at the National Institute for Communicable Diseases, cases have been on the decline across most regions of the world, but for about five weeks South Africa has seen a steady rise that has “been especially steep lately”.
She said the positivity rate had increased in every province but there has been no increase in recorded or excess deaths.
On hospital admissions, she said “a higher number of young people are being admitted than in earlier waves” but “the older are the most vulnerable and make up the highest proportion of admissions”.
