AstraZeneca Kovid-19 vaccine weakens against South Africa tensions

Approximately 2,000 volunteers enrolled, with an average age of 31, were too young to test and its participants were too young to draw broad conclusions on the vaccine’s overall efficacy to protect against disease caused by coronovirus, especially when it When it comes to hospitalization or death. . However, its findings concern that a mutated virus is making existing Kovid-19 vaccines less effective and shots will need to be updated to protect against new virus strains.

Johnson & Johnson & Novavax Inc.

Those whose vaccines have not yet been authorized in any country have also found that their shots were less effective in recent human clinical trials in South Africa, compared to trials in the US or the UK, but their vaccines still 50% or more were found to be effective in preventing mild or moderate cases of Kovid-19 and even more potent in protecting acute illness and hospitalized patients from new stress.

The Sunday news on the AstraZeneca trial in South Africa did not provide efficacy rates for vaccination. The Johnson & Johnson trial in South Africa involved approximately 6,500 people, while the Novavax had 4,400.

The University of Witwatersrand in Johannesburg, which tested the AstraZeneca, said it could not assess whether the vaccine prevented more severe cases of Kovid-19, as relatively younger test participants had a lower risk of becoming seriously ill. Was.

Nevertheless, the South African trial’s lead investigator and scientists at the University of Oxford, who developed the vaccine with AstraZeneca, said that based on the results of other vaccine trials, they were optimistic that their shot would provide protection from severe Kovid-19. Will do.

“This study confirms that the epidemic will continue to spread in the coronavirus vaccine population as expected,” Andrew Pollard, director of the Oxford Vaccine Group at the University of Oxford, said in a news release on the test results. “But, taken with promising results from other studies in South Africa using a similar viral vector, vaccines may continue to reduce the toll on health care systems by preventing critical illness.”

A spokesperson for AstraZeneca said the company believes “our vaccine can protect against serious illness.” Like other vaccine manufacturers, AstraZeneca says that it is working on updating its shots to target new variants of the virus. It hopes to have a new vaccine prepared by fall.

The South African strain, known as B.1.351, is already responsible for most infections in South Africa and has been blamed for a sharp increase in Kovid-19 cases in countries such as Mozambique and Zambia in recent weeks is.

Researchers in the US, Canada, Israel, and several European and African countries have also detected it in samples from people without recent travel history in positive coronavirus tests, suggesting that it is spreading in the community. In total, it has been identified in 32 countries, and virologists say that it is likely to be present in others that do not perform systematic sequencing of samples tested positive.

Scientists in South Africa and the UK believe that the strain of B.1.351 is about 50% more infectious than earlier versions of the virus, compared to South Africa’s first and biological studies of Kovid during the second wave of South Africa -19 is based on a very rapid increase in infection. Changes in the structure of viruses.

South African researchers have stated that the B.1.351 variant does not appear for more deaths or more severe cases of Kovid-19.

Ravi Gupta, a professor of clinical microbiology at the University of Cambridge who was not involved in the South African AstraZeneca vaccine trial, said Sunday’s results underscore the need to update the current crop of Kovid-19 vaccine against new variants. Nevertheless, he said, he hopes the AstraZeneca shot will still provide some protection against the new strain. “We certainly still need to use vaccines to protect people from serious illness,” he said.

Concern over the South African version and its effect on vaccine efficacy focuses on a mutation called E484K. Researchers believe that this mutation makes it harder for antibodies to get a grip and neutralize the virus.

The same mutation has also been found in a different variant discovered in Brazil. Researchers in the UK said earlier this month that they had found the E484K mutation in a small number of patients infected with another rapidly spreading coronavirus variant that is driving infections there.

-Jenny Strasberg contributed to this article.

Improvement and amplification
In a South African trial of AstraZeneca’s Kovid-19 vaccine, the average age of volunteers was 31 years. An earlier version of this article incorrectly stated that his average age was 32 years.

write to Gabrielle Steinhauser at [email protected]