without review by other scientists.
The study was conducted on blood taken from people who had received the vaccine.
Pfizer tested the blood against some mutations found on the virus, and not the virus itself.
They looked at three mutations - N501Y (in both the UK and South African variant), 69/70 deletion (UK) and E484K (South African).
The most worrisome mutation is E484K because it is known to escape antibodies.
This is the first signal from Pfizer that their vaccine does have some protectiveness against E484K, which is also in the new Brazilian variants.
But all coronavirus strains have dozens of mutations, and so the findings from Pfizer are limited at this stage.
The scientists are currently engineering a virus with the full set of South African mutations and expect to have results from that in around two weeks, according to Pei-Yong Shi, an author of the study.
Sir Jeremy Farrar said travel bans would 'buy time' for health providers to get people vaccinated Speaking to BBC Radio 4's Today programme Sir Jeremey warned that transmission needed to be driven down to stop new strains.
He said that travel restrictions would "buy time" but needed to be used to change the fundamentals through the rollout of vaccines.
Sir Jeremy added: "And it has to be very, very smart and very comprehensive and go on for a long time.
"Look at what New Zealand and Australia are going through at the moment with travel restrictions."
Sir Jeremy said that the only way to avoid travel bans remaining for long periods of time was "to get vaccines to the world and reduce the amount of transmission around the world."
"That's the moral and that's the ethical thing to do. It also happens to be the financial and economic best way to get out of the pandemic."
Millions of Brits have already received their Covid vaccines Credit: PA:Press Association Vials of the vaccine made by Pfizer and BioNTech Credit: AP:Associated Press Pfizer has already said its Covid vaccine is likely to protect against the UK strain .
So far results do not indicate that another jab will be needed to protect against new variants, the firm said.
The results are more encouraging than another non-peer-reviewed study from scientists at Columbia University, published yesterday.
It showed antibodies generated by the jabs were significantly less effective against the South Africa variant using a different study method.
It comes after Moderna said its vaccine - which won’t be available in the UK until spring - will be less potent against the South African variant .
The company found the jab, using the same technology as that made by Pfizer, produced six times fewer antibodies against the strain.
However, the vaccine produced a high enough level of antibodies to kill the strain, Moderna claimed.
The firm is now making another jab (mRNA-1273.351) against the variant which could be used if needed as a booster one year after people received the original vaccine.
The South African coronavirus strain, which is more easily spread and potentially more deadly , is causing more concern than the one that first emerged in the UK.
Studies so far suggest vaccines will work against the UK variant, which is also transmissible and deadly .
The UK variant has made controlling the virus outbreak harder, and the Government is in a race to vaccinate as many as possible to drive down hospitalisations and deaths.
So far 7.16 million people in the UK have received their first jab from either Pfizer or AstraZeneca.
It means the UK is more than halfway towards its target of inoculating almost 14 million of the most vulnerable Brits by February 15.
Yesterday Prime Minister Boris Johnson said the "vaccine rollout has to continue to be successful, as it currently is" in order for lockdown to be lifted in the future, starting with schools opening on March 8, at the earliest.
“And we need to make sure the infection rate is in the right place and we’re continuing as a country to work together to drive it down by the means we’re currently using", the PM told the Downing Street briefing.
“We’re going to keep it all under constant review, particularly on February 15 when we will know whether we’ve hit our target of getting those most vulnerable groups vaccinated.”
EU tells UK-based Covid vaccine maker AstraZeneca it has a moral responsibility to supply the 27-member bloc as jab row escalates