The government of Israel says its analysis has shown that Pfizer-BioNTech’s coronavirus vaccine appears to be less effective against infections caused by the delta variant compared to other covid-19 strains.
In a brief statement issued Monday, the government said that as of June 6, the vaccine provided 64% protection against infection. In May, when the alpha variant was dominating in Israel and the delta strain had not yet spread widely, he found that the vaccine was 95.3% effective against all infections.
The government added that the vaccine was now 93% effective in preventing serious illness and hospitalizations, compared with 97% reported in The Lancet medical journal in May.
The statement cites top-line figures, but did not disclose underlying data or other details about its analysis. A team from the Hebrew University said in a separate statement that it was too early to know how much the delta variant affected the vaccine’s efficacy.
Dr. Ashish Jha, dean of the Brown University School of Public Health, was also cautious in drawing conclusions.
“The best data still suggests that mRNA vaccines offer a high degree of protection against infection and excellent protection against serious diseases. Let’s wait for more data, but for now if you are vaccinated, I would not worry,” he tweeted.
In another statement on Tuesday, Israel’s Health Ministry released some facts about the disease caused by covid-19 and offered an expanded explanation of the vaccine’s protection.
Despite an apparent decline in the vaccine’s ability to prevent all infections during the spread of the delta variant, the statement underscored its continued benefit in preventing severe cases.
Israel has rolled out the Pfizer vaccine for everyone over the age of 12, and its early and rapid application gave scientists one of the first real-world snapshots of its effectiveness.
The government said the drop in efficiency is likely due to the spread of the delta variant in Israel. This most infectious strain of the virus was first identified in India earlier this year and is also known as B.1,617.2.
Pfizer said it could not comment on unpublished data, but a recently published laboratory study it conducted with the University of Texas Medical Branch found that its vaccine was effective against laboratory versions of the delta variant and others.
The study found that full vaccination elicits an immune response that should protect people well against infection with the new variants.
Israel is one of the most vaccinated countries in the world, with more than 60% of the population completely inoculated and two-thirds having received at least one dose.
The statement highlights a great risk in the future: the appearance of new variants that could evade some of the protection provided by vaccines.
Public health officials stress that current vaccines offer good protection against the delta variant.
A study by Public Health England found this month that the Pfizer-BioNTech and Oxford-AstraZeneca vaccines were each highly effective, 96% and 92% respectively, against hospitalizations for the delta variant after two doses.
Separately, preliminary findings from a Scottish study published in The Lancet last month found that Pfizer’s vaccine provided 79% protection against all delta variant infections, compared to 92% against the alpha variant.
The same study, which analyzed data from 5.4 million people in Scotland, found that the Oxford-AstraZeneca vaccine offered 60% protection against infection with the delta variant compared to 73% for the alpha variant.
In laboratory experiments, Moderna’s vaccine was found to work against newer variants such as delta, the company said.
Johnson & Johnson said laboratory tests of its single-dose coronavirus vaccine suggest it provides protection against the delta variant.
However, this can change if the virus mutates further. That is why doctors and public health authorities want more people to get vaccinated. “The more we allow the virus to spread, the more opportunities the virus has to change,” the World Health Organization (WHO) warned last month.
Israel lifted most of its coronavirus restrictions in early June. However, the government later reinstated an indoor mask use mandate after an increase in cases caused by the delta variant.
He also appointed a “special manager” to prevent the entry of the coronavirus and its variants into Israel and approved a plan to build a permanent facility for testing at Ben Gurion Airport.
The country has reported a slight increase in daily cases in recent weeks, but only a handful of people have died from the disease in Israel in the past month.
Meanwhile, England, where the delta variant has become the dominant strain, is pushing ahead with its plan to remove most of the remaining restrictions in just two weeks, despite strong warnings from many scientists.
Speaking at a news conference on Monday, UK Prime Minister Boris Johnson said that the effectiveness of the death vaccine was allowing the government to lose focus, although the number of cases is increasing rapidly.
He said the government needed to balance the risk of the virus and the impact of the restrictions on people, adding that the country “must find a new way to live with the virus.”
“I want to emphasize from the beginning that this pandemic is far from over, we are seeing the cases increase quite rapidly. There could be 50,000 cases detected per day and again as we predicted we are seeing an increase in hospital admissions, and we must sadly acknowledge that there will be more deaths from covid,” added Johnson.
The WHO has warned against this approach. “Many countries seem to be completely abandoning the idea that we have some control over this virus,” Dr. Mike Ryan, WHO’s executive director for health emergencies, said Monday during a question-and-answer session.
He warned against any “premature rush” to reopen at a time when cases are increasing.
“We seem to be very caught up in the headlines that there is nothing we can do, it is inevitable that we will see these waves and it is inevitable that hospitals will fill up and inevitable that cemeteries will fill up,” he said. “It is not inevitable, it can be stopped, but it will require one more effort from communities that are already exhausted.”