Western governments rushed to offer support for the AstraZeneca Covid-19 vaccination after South Africa stopped the rollout when research showed that it offered minimal protection against mild infection from a variant that spreads there. Despite concerns, the lead investigator about the South African trial of the vaccine said he believed it had an important role to play in the fight against the virus.
The advent of vaccines has given hope that researchers can tame a pandemic that has killed 2.3 million people worldwide.
Shabir Madhi from the University of the Witwatersrand in Johannesburg, who was the lead investigator for the vaccine trial, said he would start rolling out the one million AstraZeneca doses already in the country immediately, as they have an expiration date in April and it would be careless. to waste them.
However, if the vaccines are less effective against new variants, they may need to be adjusted and people may need booster shots.
South Africa announced its halt after researchers from the University of Witwatersrand and the University of Oxford found that the AstraZeneca vaccine provided only minimal protection against mild or moderate infection from the B.1.351 variant, now the dominant form of the virus in that country.
The research has not yet been peer-reviewed and did not provide data on older people who are likely to die or need hospitalization.
There were no data on whether the vaccine would prevent serious illness, and researchers said it was still possible.
“This study confirms that the coronary pandemic virus will find ways to continue to spread in vaccinated populations, as expected,” said Andrew Pollard, chief investigator of the Oxford vaccine trial.
“But with the promising results of other studies in South Africa with a similar viral vector, vaccines can continue to alleviate the health care system by preventing serious disease.”
French Health Minister Olivier Véran expressed support for the AstraZeneca vaccine, claiming it provided adequate protection against “almost all variants” of the virus.
German Health Minister Jens Spahn said current evidence suggests that all three vaccines approved in Europe – including AstraZeneca – provided effective protection against serious infections.
The UK and Australia called for calm and cited evidence that the vaccines prevented serious illness and death, while AstraZeneca said it believed its vaccine could protect against serious illness.
“We believe that both of the vaccines we are currently using are effective, as I say, in stopping serious illness and death,” British Prime Minister Boris Johnson told reporters.
The UK is also using the Pfizer shot.
“We also believe, especially in the case of the Oxford AstraZeneca vaccine, that there is good evidence that it stops transmission, I also believe that there is a 67% reduction in transmission.”
Australia is expected to approve the use of the AstraZeneca vaccine within a few days and expressed confidence in it.
“There is currently no evidence to suggest a reduction in the effectiveness of the AstraZeneca or Pfizer vaccines in preventing serious diseases and deaths. It is a fundamental task to protect health,” said Health Minister Greg Hunt.
But if vaccines do not work as effectively as hoped for new and emerging variants, the world could face a much longer – and more expensive – fight against the virus than we previously thought.
The AstraZeneca vaccine was the great hope for Africa because it is cheap and easy to store and transport. South Africa, which has hoped to launch the AstraZeneca shot this month, stores about one million doses it has received from the Serum Institute of India.
The B.1.351 variant dominant in South Africa, also known as 20I / 501Y.V2, is also circulating in at least 40 other countries, including the United States. Other important variants include a first found in the UK, known as 20I / 501Y.V1, and one found in Brazil known as P.1.
Austria warned of non-essential travel to its alpine province of Tyrol due to an outbreak of the South African variant there. Cases were also discovered north of Paris, forcing a school to close.
An analysis of infections with the South African variant showed that there was only a 22 percent lower risk of developing mild to moderate Covid-19, more than 14 days after being vaccinated with the AstraZeneca shot, compared to those receiving placebo.
Protection against moderately severe illness, hospitalization or death could not be assessed in the study of approximately 2000 volunteers who had a median age of 31 years, because the target population had such a low risk.
Professor Shabir Madhi, lead researcher on the AstraZeneca study in South Africa, said that the vaccine’s similarity to another produced by Johnson & Johnson, which reduced serious illness by 85 percent, suggested that it would still prevent serious illness or death.
“There is still some hope that the AstraZeneca vaccine can work just as well as the Johnson & Johnson vaccine in another demographic age group that I treat for serious illness,” he told BBC Radio.
Sarah Gilbert, professor of vaccinology at the University of Oxford, said that efforts are underway to develop a new generation of booster shot vaccines that enable protection against new variants.
“This is the same issue that all vaccine developers face, and we will continue to monitor the emergence of new variants that emerge in preparation for a future strain change.”
( Jowharwith REUTERS)