The UN health agency says there is no causal link between the AstraZeneca vaccine and blood clots.
The Pfizer-BioNTech and Oxford-AstraZeneca vaccines have been found to be highly effective against the coronavirus variant that was first identified in India, according to a study by Public Health England (PHE).
The Pfizer vaccine was 88-percent effective and the AstraZeneca jab was 60-percent effective against the B1617.2 strain after the second dose.
Both the vaccines were more effective against the so-called “Kent” strain – B.1.1.7, the COVID-19 variant dominant in Britain – with Pfizer being 93-percent effective while the AstraZeneca jab was 66-percent effective over the same period.
However, they were only 33-percent effective three weeks after the first dose.
Health Secretary Matt Hancock described the outcome as “groundbreaking,” while PHE said it expects to see even higher levels of effectiveness against hospital admission and death.
“This new evidence is groundbreaking and proves just how valuable our COVID-19 vaccination programme is in protecting the people we love,” Hancock said.
Earlier this month, the World Health Organization (WHO) dubbed the B1617.2 strain a “variant of global concern”.
The study, which took place between April 5 and May 16, found that both the vaccines were 33-percent effective against symptomatic disease from the B1617.2 strain three weeks after the first dose, compared with about 50 percent against the B.1.1.7 strain.
Some 12,675 genome-sequenced cases were included in the analysis, but only 1,054 were of the variant identified in India. The study included data for all age groups from April 5 to cover the period since the strain emerged.
New data from PHE shows there have been at least 2,889 cases of the B1617.2 strain recorded in England from February 1 this year to May 18.
Of those, 104 cases resulted in a visit to a hospital emergency department, 31 required overnight hospital admission and six resulted in a death.
The most common strain in England, according to the data, is the B.1.1.7 variant, with 132,082 cases recorded over the same period. The virus has infected 4.46 million people and caused the death of 128,000 people in the UK since its outbreak last year.
Dr Mary Ramsay, head of immunisation at PHE, added: “This study provides reassurance that two doses of either vaccine offer high levels of protection against symptomatic disease from the B1617.2 variant.
“We expect the vaccines to be even more effective at preventing hospitalisation and death, so it is vital to get both doses to gain maximum protection against all existing and emerging variants.”
Separate analysis by PHE indicates that the vaccination programme has so far prevented 13,000 deaths and about 39,100 hospital admissions in older people in England, up to May 9.
Under the government’s plans, a lifting of remaining coronavirus restrictions is due to take place from June 21.
The latest figures show that more than 50 million doses of coronavirus vaccine have been given in Britain in Europe’s fastest vaccination programme so far, but it has faced a new challenge from the spread of the variant first found in India.
Data published on Saturday showed new COVID cases reported in Britain rose by 10.5 percent in the seven days to May 22 although it remained a fraction of levels seen earlier this year.
Prime Minister Boris Johnson this month ordered a ramping up of administering second vaccine doses to people over 50 and those who are clinically vulnerable.
Concern about rising cases in Britain of the variant first found in India prompted Germany to say on Friday that anyone entering the country from the United Kingdom would have to quarantine for two weeks on arrival.