Vaccine vs. variant: promising data in Israel’s race to defeat the pandemic

JERUSALEM (Reuters) – Israel’s rapid roll-out of vaccination has made it the largest real-world study of Pfizer Inc.’s COVID-19 vaccine. The results are pouring in and they are promising.

More than half of eligible Israelis – around 3.5 million people – have now been fully or partially vaccinated. Older and at-risk groups, the first to be vaccinated, are seeing a dramatic drop in disease.

Among the first fully vaccinated group, there was a 53% reduction in new cases, a 39% drop in hospitalizations and a 31% drop in serious illness from mid-January to February 6, Eran Segal said, data scientist at the Weizmann Institute. of Science in Rehovot, Israel.

(Graphic: Trends in COVID-19 infections and hospitalizations in Israel after vaccination -)

During the same period, among people under the age of 60 who later became eligible for the vaccine, new cases fell 20%, but hospitalizations and serious illness increased by 15% and 29%, respectively .

Reuters asked leading scientists in Israel and abroad, Israeli health officials, hospital heads and two of the country’s largest healthcare providers about what new data shows of the deployment of most effective vaccine in the world.

The vaccination campaign provided a database offering information on the effectiveness of vaccines outside of controlled clinical trials and how countries could achieve sought-after but elusive herd immunity.

More will be known in two weeks, as teams analyze vaccine effectiveness in younger groups of Israelis, as well as target populations such as people with diabetes, cancer and pregnant women, among a base. patients at least 10 times greater than those in clinical studies.

“We need to have enough people in this subgroup and enough follow-up time for you to draw the right conclusions, and we’re getting to this point,” said Ran Balicer, Chief Innovation Officer of HMO Clalit, who covers more than half of the Israeli population.

Pfizer monitors the Israeli deployment on a weekly basis for information that can be used around the world.

As a small country with universal healthcare, advanced data capabilities and the promise of rapid deployment, Israel has provided Pfizer with a unique opportunity to study the real impact of the vaccine developed with BioNTech in Germany.

But the company said it remained “difficult to predict exactly when herd protection might start to kick in” because of many variables at play, including social distancing measures and the number of new infections generated by the herd. each case, known as the reproduction rate.

Even Israel, at the forefront of the global immunization campaign, has lowered expectations of a quick exit from the pandemic due to the surge in cases.

A third nationwide lockdown has struggled to contain transmission, attributed to the rapidly spreading UK variant of the virus. On a positive note, the Pfizer / BioNTech shot appears to be working against him.

“We have so far identified the same 90% to 95% effectiveness against the British strain,” said Hezi Levi, director general of Israel’s Ministry of Health.

“It is still too early, because we only finished the first week after the second dose,” he said, adding: “It is too early to say anything about the South African variant. “

WHICH ARM?

Israel began its vaccination program on December 19 – the day after Hanukkah – after paying a premium for the supply of the Pfizer / BioNTech vaccine.

Four days later, the most contagious British variant was detected in four people. While the vaccine prevents illness in the elderly, the variant now accounts for around 80% of new cases.

Finding itself in a race between the vaccine and the new variant, Israel began giving vaccines to those over 60 and gradually opened up the program to the rest of the population.

Every detail was digitally tracked, up to which arm the patient was pricked and which vial it came from.

A week after receiving the second dose of Pfizer – the time at which full protection should kick in – 254 out of 416,900 people were infected, according to Maccabi, a major Israeli health care provider.

(Graphic: COVID-19 infections in vaccinated people -)

Comparison with an unvaccinated group found a vaccine efficacy of 91%, Maccabi said.

22 days after complete vaccination, no infection was recorded.

Israeli experts believe vaccines rather than lockdowns have driven the numbers down, based on studying different cities, age groups and pre-vaccine lockdowns.

The comparisons were “compelling in telling us that’s the effect of the vaccination,” said Segal of the Weizmann Institute.

With 80% of seniors partially or fully vaccinated, a more complete picture will begin to emerge this week.

“And we expect a further decline in overall cases and cases of severe morbidity,” said Balicer, of HMO Clalit.

VACCINES AND TRANSMISSION

There may be early signs that vaccinations reduce the transmission of the virus in addition to the disease

At Israel’s largest COVID-19 testing center, run by MyHeritage, researchers tracked a significant decrease in the amount of people infected with the virus, known as the cT value, among the most aged age groups. more vaccinated.

This suggests that even if vaccinated people are infected, they are less likely to infect others, said Yaniv Erlich, scientific director of MyHeritage.

“The data so far is probably the clearest in Israel. I believe these vaccines will reduce future transmission, ”said Stefan Baral, of the Johns Hopkins School of Public Health in Maryland.

DECREASING RETURNS

It is not known whether Israel will be able to maintain its world-leading vaccination rate.

“When you vaccinate quickly and a lot, you end up getting into hardcore – those who are less willing or harder to reach,” said Boaz Lev, head of the Department of Health’s advisory committee.

The timing of vaccination is even more crucial with the rapid transmission of the British variant.

“In the race between the spread of the UK variant and the vaccinations, the end result is that we are seeing a kind of plateau when it comes to those who are seriously ill,” Segal said.

The big question is whether vaccines can eradicate the pandemic.

Michal Linial, professor of molecular biology and bioinformatics at the Hebrew University of Jerusalem, said data from decades past suggests viruses are becoming endemic and seasonal.

She predicted that this coronavirus would become much less aggressive, possibly requiring a booster within three years.

“The virus is not going anywhere,” she concluded.