Covid-19 vaccine booster shots may be offered to healthcare workers before the end of the year, based on the latest scientific evidence, said Prof Glenda Gray, co-principal investigator of the Sisonke study which delivered J&J shots to them, from February to May this year.
“The decision will be data-driven and based on available evidence. At a global level, boosters are being given and, at a policy level, SA is evaluating the timing of boosters. This needs to be not too early or too late,” she said.
Research from the UK last week found that protection against Covid-19 provided by two doses of the Pfizer or the Oxford/AstraZeneca vaccines begins to fall within six months, from 88% to 74% and 77% to 67% respectively.
“The J&J vaccine has great durability, lasting eight to nine months, but a booster does augment the immune response remarkably,” said Gray, referring to clinical trial results testing the impact of two doses.
The J&J vaccine works effectively to prevent severe disease and death as a single-dose vaccine.
A single J&J shot means a person is fully vaccinated, unlike the Pfizer vaccine — also being rolled out in SA’s vaccination programme — which requires two jabs for full protection.
Gray said she was encouraged to see the enthusiasm of the 18-plus age group to get vaccinated during the past week.
The smooth symmetry in most provinces in the first and second waves may have lulled us into complacency.
— Wits professor of medicine Francois Venter
Her 27-year-old daughter was one of them and it was a profound moment in her life.
“This group are voting with their feet to get it. Like the healthcare workers, they seem to have done the risk-benefit assessment,” said Gray, who is also president of the SA Medical Research Council.
Wits professor of medicine Francois Venter said of this increased uptake: “Every time we drop the age threshold, there is a rush of the willing to get their shot. Then the numbers drop. I’m pretty sure the same will happen here, though I hope I am wrong.”
He said the health department had begun to make vaccine access more convenient. “We need even more of what is finally starting to happen, vaccines being taken to people rather than the other way round — to taxi ranks, malls, drive-throughs and places where people gather.”
Asked about booster vaccines for the population, Venter said: “The data is that our J&J and Pfizer vaccines work brilliantly against all the current variants. Let’s stop worrying about boosters and worry about the terrifyingly low number of people vaccinated.”
The World Health Organisation has called on countries not to use boosters yet, given the demand for vaccines and the low availability to date in low-income countries.
Only 1.6% of the population in low-income countries has received a single dose of a Covid-19 vaccine, compared to 22,8% in SA and 33,4% of the global population, according to OurWorldInData.
Venter said the next few weeks and months would produce more research on boosters. “We can afford to wait and rather focus our energy on getting the unvaccinated jabbed,” he said.
Vaccinating the population before the fourth wave hits is a priority, Venter declared.
On the prolonged third wave, he said: “We thought it was tapering off, but it seems to be grumbling on or even increasing in places. The trajectory is certainly more complex than the first two waves outside Gauteng.
“The smooth symmetry in most provinces in the first and second waves may have lulled us into complacency into calling an end to this wave.”
It is difficult to know definitively when the third wave will end, said Wits researcher and biostatistician Lise Jamieson, on behalf of the SA Modelling Consortium.
She said that KwaZulu-Natal, the Free State and the Eastern Cape still have a high rate of new Covid-19 cases and, in most of their districts, cases increased by more than 20% over the past week.
“Most districts across SA” had a high weekly rate of new cases, she said, noting the unexpected patterns of the third wave.
“The third wave has been somewhat different to the previous two waves, in that new cases have not declined as before, and it has been rather drawn out.
“This is possibly due to transmission of the Delta variant starting later in some provinces, in some instances on top of an ongoing Beta wave, and the adherence to non-pharmaceutical interventions (mask wearing, social distancing and avoiding crowded indoor places) and vaccinations not being enough to reduce transmission,” Jamieson said.
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