A new study has suggested that the Oxford/AstraZeneca vaccine provides ‘minimal protection’ against mild to moderate infection with the South African variant of the virus.
But another study has suggested that the vaccine is effective against the Kent mutation of coronavirus.
It comes as the vaccines minister has confirmed that GPs could be administering Covid variant ‘booster shots’ later this year – perhaps in the autumn.
A new preprint study from Wits University in Johannesburg yesterday announced the results of the Oxford Covid vaccine trials in South Africa, which included around 2,000 volunteers with a median age of 31.
The paper, which is yet to be peer-reviewed, shows that two doses of the vaccine ‘provides minimal protection against mild-moderate Covid-19 infection’ from the variant identified in South Africa in November, the University said.
However, efficacy against ‘severe’ Covid infection from the variant, hospitalisation or death was not assessed because the target population were ‘at low risk’, it added.
And the analysis suggested the vaccine had ‘high efficacy’ against the original virus variants, the University said.
It added that the data suggests that ‘mutations in the virus seen in South Africa will allow ongoing transmission of the virus in vaccinated populations’.
Shabir Madhi, professor of vaccinology and director of the Vaccines & Infectious Diseases Analytics (VIDA) Research Unit at University of the Witwatersrand, and chief investigator on the trial in South Africa, said the findings could ‘shift focus’ away from herd immunity against transmission to protection of those most at risk.
He added that recent South African studies of the Janssen vaccine, which uses similar technology to the Oxford vaccine, indicated that protection was ‘preserved’ for moderate to severe disease.
Professor of vaccinology at the University of Oxford Sarah Gilbert reiterated that researchers are working with AstraZeneca to develop variant vaccines for booster jabs ‘if necessary’.
Meanwhile, a preprint study published last week in The Lancet by the University of Oxford showed that the Oxford vaccine is effective against the Kent variant of Covid.
The paper, which is also not yet peer-reviewed, said the vaccine’s efficacy against the variant is ‘similar’ to that for other coronavirus variants and that the vaccine results in ‘a reduction in the duration of shedding and viral load, which may translate into a material impact on transmission of disease’.
Vaccine deployment minister Nadhim Zahawi today said that recent studies show that both vaccines currently deployed in the UK ‘appear to work well against the Covid-19 variants currently dominant in the UK’.
He added: ‘In terms of other variants, not in the UK, we need to be aware that even where a vaccine has reduced efficacy in preventing infection there may still be good efficacy against severe disease, hospitalisation, and death. This is vitally important for protecting the healthcare system.
‘While it is right and necessary to prepare for the deployment of an updated vaccine, we can take confidence from the current rollout and the protection it will provide all of us against this terrible disease’.
Speaking on BBC One’s Andrew Marr Show yesterday, Mr Zahawi said there is likely to be a follow-up jab programme in the autumn to respond to variants of the virus.
He said: ‘We see very much probably an annual [jab] or booster in the autumn and then an annual [jab], in the way we do with flu vaccinations where you look at what variant of virus is spreading around the world, rapidly produce a variant of vaccine and then begin to vaccinate and protect the nation.’
The number of people who have now received a first dose of either the Oxford or Pfizer/BioNTech Covid vaccine has now surpassed 12m, including ‘over 90%’ of over 75s, Mr Zahawi added today.
He said: ‘We’re now vaccinating at an incredible pace, and during one hour on Saturday we delivered nearly 1,000 jabs a minute across the United Kingdom.’
On Friday, the Government announced an agreement with vaccine manufacturer CureVac to ‘rapidly develop new vaccines’, with an initial 50m doses of modified vaccines pre-ordered for delivery ‘later this year if they are required’.