Doubts about effectiveness of vaccine NZ has ordered
AUCKLAND: South Africa will suspend use of the same Covid19 vaccine that New Zealand has prepurchased millions of doses of, over concerns it may not be fully protective against a new variant.
The move came on the back of a new analysis, released before peerreview, that found the OxfordAstraZeneca’s ChAdOx1 vaccine provided only minimal protection against mildmoderate Covid19 infection from the B.1.351 (South Africa) coronavirus variant.
The variant, first identified in South Africa in midNovember, has since been confirmed in cases in New Zealand’s borders.
The analysis, carried out by the Wits Vaccines and Infectious Diseases Analytics (Vida) Research Unit which runs the Oxford Covid19 vaccine trial in South Africa, was carried out on about 2000 volunteers, with a median age of 31.
The tests did not focus on protection against moderatesevere disease, hospitalisation or death, as the vaccine’s target population was at low risk.
The results showed that, while the vaccine had high efficacy against the original coronavirus nonB.1.351 variants in South Africa, its effect on the new strain was substantially reduced.
South Africa had planned to deliver the shot to healthcare workers soon, having received about 1 million doses, but would now instead offer other vaccines by Johnson & Johnson and Pfizer.
Work was already under way at the University of Oxford to produce a second generation of the vaccine, which has been adapted to target variants with mutations similar to B.1.351.
Prof Andrew Pollard, the Oxford vaccine trial’s chief investigator, said the study confirmed the coronavirus would find ways to continue to spread in vaccinated populations.
It is unclear what the development means for New Zealand’s vaccine rollout — and the Ministry of Health has been contacted for comment.
Under its prepurchase agreement, New Zealand has signed up to receive about 7.6 million doses of the OxfordAstraZeneca vaccine, enough for 3.8 million people.
On Friday, it was reported New Zealand could be sent nearly 250,000 doses of the vaccine before July, as part of its membership in the global Covax alliance.
New Zealand has prepurchased four vaccines, from Pfizer and BioNTech; Janssen Pharmaceutica; Novavax; and AstraZeneca.
The first purchase agreement was for 1.5 million vaccines from Pfizer and BioNTech, which MedSafe granted provisional approval for last week.
This is enough for 750,000 people and each person will need two doses of this vaccination, about a month apart.
An inprinciple agreement has been signed with Janssen Pharmaceutica to buy up to 5 million vaccines — likely to be a single dose.
In December, the Government signed a further agreement with Novavax to buy 10.72 million doses of its vaccines — enough for two doses for 5.36 million people — but this is not expected until later this year.
There were no cases of Covid19 yesterday, either in the community or in managed isolation, the Ministry of Health announced.
Health officials are yet to reveal whether genomic testing has linked the Hamilton Covid19 case to others from the Pullman Hotel. The sequencing will be rerun later this week as the viral load in the sample was so low.
The person stayed in the managed isolation hotel between January 16 and 30 but tested positive on Saturday after isolating at home.
The case is considered to be historic, not infectious, and the person has been discharged from the quarantine facility. — The New Zealand Herald