The World Health Organisation (WHO) has described South Africa’s decision to temporarily pause planned rollout of the Oxford-AstraZeneca COVID-19 vaccine, as “concerning news.’’
WHO Director-General, Dr Tedros Ghebreyesus said this at a news conference on COVID-19 at WHO headquarters in Geneva on Tuesday.
Ghebreyesus was reacting to the announcement by South Africa to temporarily suspend rollout of the Oxford-AstraZeneca vaccine after a relatively small study revealed it provided reduced protection against the variant first identified in the country
According to him, the emergence of new coronavirus variants has raised major questions around whether currently available vaccines will be effective against them.
The director-general, however, described the development as “concerning news”, though noting important caveats related to the study.
“These results are a reminder that we need to do everything we can to reduce the circulation of the virus with proven public health measures.
“It also seems increasingly clear that manufacturers will have to adjust to the evolution of the virus, taking into account the latest variants for future shots, including boosters.
“The Oxford-AstraZeneca vaccine is among several found to be effective in preventing severe disease, hospitalisation and death from COVID-19,’’ he said.
Ghebreyesus said the South African study showed it was minimally effective at preventing mild to moderate illness caused by the variant first identified there, known as 501Y.V2.
“Given the limited sample size of the trial and the younger, healthier profile of the participants, it is important to determine whether or not the vaccine remains effective in preventing more severe illness,” he said.
Some 2,026 participants took part in the trial, according to Prof. Salim Abdool Karim, co-chair of South Africa’s Ministerial Advisory Committee on COVID-19.
“While the overall efficacy of the AstraZeneca vaccine was 66 per cent in the larger study that includes the UK, Brazil and South Africa, the South African data on its own showed only 22 per cent efficacy.
“We know from the overall trial that the AstraZeneca vaccine is effective against other pre-existing variants. We’re just not confident about its efficacy against the 501Y.V2 variant,” he said.
Karim said South Africa was considering a proposal to roll out the vaccine among 100,000 people initially and monitoring their hospitalisation rates based on a threshold.
In a related development, the director-general said WHO had dispatched a research team to the eastern Democratic Republic of the Congo (DRC) where Ebola had resurfaced after a previous outbreak was declared over last June.
Congolese authorities announced on Sunday that a new case was reported near the city of Butembo, in North Kivu province, located in a region which had beat back the disease following nearly two years of battle.
The woman, who has since died, was married to an Ebola survivor.
WHO is supporting local and national authorities to trace more than 70 contacts, while sites she visited are being disinfected.
According to Ghebreyesus, so far, no other cases has been identified, but it is possible there will be further cases because the woman had contact with many people after she became symptomatic.
“Vaccines are being sent to the area and we hope that vaccination will start as soon as possible,” he said.