Top immunologist: Douse Israel’s Delta ‘fire’ before it needs lake-full of water

Cyrille Cohen talks Delta dynamics and booster shots, raises concerns and sounds warning alarm while also suggesting variant may further immunize some people for uncertain future

Nathan Jeffay is The Times of Israel's health and science correspondent

Family members wearing safety gear visit a family member at the coronavirus ward of Shaare Zedek hospital in Jerusalem on February 3, 2021. (Yonatan Sindel/Flash90)
Family members wearing safety gear visit a family member at the coronavirus ward of Shaare Zedek hospital in Jerusalem on February 3, 2021. (Yonatan Sindel/Flash90)

Israel can still rein in the Delta variant of the coronavirus, but if it doesn’t act decisively it will need “a lake-full of water instead of a bucket to put out the fire,” according to a leading immunologist.

“The numbers of infections are not going down, so we will eventually have a few hundred people in critical care if we don’t stop the spread,” Professor Cyrille Cohen of Bar Ilan University told The Times of Israel. “That’s the trajectory. But it can be stopped.”

He made his comments after Israel recorded 855 new cases of the coronavirus Thursday, and as the number of active cases reached 5,800, the highest figure since April. The number of Israelis seriously ill stood at 52.

Also on Thursday, Nachman Ash, the new director-general of the Health Ministry, warned that a lockdown may be on the cards for the High Holiday season in September. “I’m worried we might get there… in a few weeks,” Ash said.

Cohen said lockdown shouldn’t be needed and that Israel just needs to cut transmission rates (known as the R-value, the number of people each virus carrier infects on average), which can be done with the right efforts. “You don’t need a lockdown, you just need to get the R under 1 and it’s not too much effort,” he said.

Cohen, head of Bar Ilan University’s immunology lab and part of a Health Ministry advisory committee on coronavirus vaccines, made the comments in a wide-ranging interview, discussing immunizations, booster shots and the concept of “living with the virus.”

He probed the complexity of Delta dynamics and suggested that despite his concerns, among those who catch the ultra-infectious strain and don’t experience bad symptoms, the infection may leave them stronger for an uncertain future.

While no one should catch COVID-19 on purpose, if vaccinated people are infected and fight Delta, it “can serve as something akin to a third dose, helping to protect against future variants that could be worse,” said Cohen.

He criticized Prime Minister Naftali Bennett’s speech on Wednesday, in which he said that Israel could beat the Delta variant within five weeks but didn’t introduce significant new measures.

However, Cohen is hopeful about the “Revelry Pass,” announced Thursday, which will limit large gatherings to only those who are vaccinated, recovered or present a negative COVID test.

People wear protective face masks against COVID-19 as they shop inside the Azrieli mall in Tel Aviv, on July 13, 2021. (Miriam Alster/FLASH90)

Times of Israel: Cases are rising, and there is some increase in serious cases. Are you concerned?

Prof. Cyrille Cohen: “I am concerned to some extent because we are seeing the numbers going up slowly but surely. Vaccines are working and slowing the pace — this should be emphasized — but vaccines alone are not able to stop the spread of the Delta variant.

“On a personal level vaccinated people are mostly protected, but the virus is spreading in society and we need to get back to an R value of 1 at a maximum, meaning that each person with the virus passes it to an average of just one other, or less [it is currently 1.31]. I think we have been wasting precious time and should have already taken measures like limiting gatherings indoors, implementing fast testing and making it easily accessible.

“The newly announced ‘revelry pass’ is a step in the right direction, but we need to enforce such regulations also in other places of gatherings such as prayer places and cinemas for example. Fighting Delta is like trying to put out a fire, and if we wait, we’ll need a lake-full of water instead of a bucket to put out the flames.”

Professor Cyrille Cohen (Courtesy)

What is the current trajectory?

“The numbers of infections are not going down so we will eventually have a few hundred people in critical care, if we don’t stop the spread. That’s the trajectory. But it can be stopped — we’re still at the point we can stop it with relatively light measures. You don’t need a lockdown, you just need to get the R under 1 and it’s not too much effort.”

Prime Minister Naftali Bennett said that Delta can be beaten in five weeks. Is he right?

“It’s doable, but only if we take stronger measures. Leaving it to the public won’t do the trick. But his speech didn’t change anything to help hit this target. I was hoping for more. Almost nothing was decided. And the language brought back memories of when Prof. Ronni Gamzu, soon after his appointment a year ago as the first coronavirus czar, gave a speech asking the public for trust and spoke of a ‘contract’ and an alliance, appealing to a more personal and sentimental feeling. We know it didn’t work then.”

Prime Minister Naftali Bennett holds a press conference at the Prime Minister’s office in Jerusalem on July 14, 2021. (Noam Revkin Fenton/FLASH90)

One decision taken was to shorten quarantine to seven days from the 10 to 14 range. Was this a good move?

“Medically speaking it’s not a bad idea. In some respect it makes sense. But think of the consequences. More people are tempted to go abroad, traveling with unvaccinated children, if the quarantine they will face is shorter. And if more people travel it’s not just a matter of people bringing back the Delta variant but potentially other variants too.”

We’re all wondering this week if our vaccine protection is waning. On Sunday, in what seemed like a bombshell report, Israeli media carried items saying that there is a correlation between infection by the Delta variant and how early people were infected. Should we be concerned?

“Not necessarily. The report suggests that you’re more likely to have COVID-19 if you were among the first to be vaccinated, which could mean that protection wanes after a few months. But I would treat this report with caution.

“There may be a correlation between infection rates and the timing of vaccination, but we need context. Let’s remember that those who rushed most to get vaccinated are those who are the oldest and often those who were most concerned about the effect of the coronavirus because they have co-morbidities. We may be seeing more the effect of who was vaccinated early than a timescale for waning immunity.”

Also disconcerting for many, as well as the report on supposedly waning protection, is talk of possible needs for a third dose. People are confused. Pfizer is seeking approval from regulators for boosters. Meanwhile, Israel has introduced them for the immunocompromised. Do we all need boosters?

“Boosters make sense for the elderly and immunocompromised, to boost their protection. But the rest of us should not worry or assume that we need them. We need more solid data regarding the efficacy of a third shot for healthy and low-risk people. We need to draw our conclusions from data, and not jump to conclusions just because Pfizer has put out a press release.

“We’re not injecting orange juice; this is a vaccine and we need to know whether it will really boost immunity and whether it’s needed. With all due respect, even after vaccine effectiveness has apparently decreased with the Delta variant, protection against severe illness is still at 93 percent, which is a wonderful number. Booster shots may be needed in due course, and if so, most likely in a differential way depending on the type of population, but we don’t have conclusions yet.”

Vials of the Pfizer-BioNTech COVID-19 vaccine are prepared for packaging at the company’s facility in Puurs, Belgium, March 2021. (Pfizer via AP)

In an interview a year ago you told me: “If we’re lucky, we’ll get a vaccine that’s effective at 90%, but if we’re less lucky, it could be 30%, and if we’re unlucky, we could get no vaccine at all. We really don’t know.” Have we perhaps formed unrealistic expectations of the vaccine because of the near-disappearance of the virus for a while?

“Maybe. People tend to forget the vaccine is not 100% effective, and it was never said that it would be. I’m not talking just about the Delta variant, but originally, before Delta arose, 5% of people were still susceptible to infection. It’s unsurprising that people are getting infected and that some reach a serious condition. People should remember COVID-19 is not unique in this respect — it’s the case with other diseases like flu, even after vaccination.”

If we do have booster shots for widespread distribution, do you think they will be adjusted to give extra protection against new variants?

“Yes, I believe this is possible. It’s conceivable and the companies are working on it, working on making a comprehensive vaccine. It’s possible that boosters will be adjusted to cover a broader part of the spike protein than current shots. The great thing about messenger RNA vaccines is that the technology allows adjustments to be made fast. It’s also possible that a booster could use a different type of vaccine than mRNA based shot.”

Much of the recent contagion in Israel has been among under 12s, who can’t be vaccinated. Is it time to start vaccinating them?

“No. We will not vaccinate kids without the results of clinical trials, which are currently underway with 4,600 children. But even then, you have to make a risk-benefit calculation, which is very different with kids, who don’t tend to get seriously sick within COVID-19, than with teens and adults. Mortality for kids has been very low and you don’t want to take risks with vaccines if the disease poses very little risk.

“We don’t have enough understanding on these vaccines for kids and to base our decisions only on a 4,600-child trial, especially as half of these will receive a placebo. This is particularly true, especially knowing about myocarditis, a heart condition that appears to be a rare side effect of the vaccine, and is most common among young males. I’d be very cautious and say at this point vaccinating young children with the main objective of protecting adults is not really warranted yet.”

Should we be worried about contagion among kids?

“I’m not overly concerned about the contagion among kids per se. But we have to take into account that they could infect their surroundings and people at risk. We can’t dismiss the idea that kids can be affected by long COVID and PIMS, which is a transient multi-inflammatory syndrome due to COVID-19 leading to persistent high fever, inflammation and sometimes organ failure. But based on what we know now, a lot are asymptomatic and don’t suffer. And while I am certainly not saying that anyone should expose their kids on purpose to the virus, there may be a positive side to infection of kids by a variant that isn’t causing them harm. Because in a sense this boosts their immunity against possible future variants that could be worse.

“For adults also, while I stress again that no one should get infected on purpose, if people are vaccinated and catch a variant that doesn’t harm them, it can serve as something akin to a third dose, helping to protect against future variants that could be worse.”

Medical personnel test Israeli children the coronavirus at a basketball court turned into a coronavirus testing center, in Binyamina, June 29, 2021. (AP Photo/Ariel Schalit)

Many in Israel say they thought ‘COVID was over.’ Is this a realistic expectation anytime soon?

“No. I think we are still understanding the dynamics of the virus. We’ve just added SARS-COV-2 to the list of viruses we need to learn to live with, like the flu. Only in a year or two hopefully will we start talking about an endemic situation, but COVID-19 is here to stay.”

Tell me more about the phrase you just used – that we need to “learn to live with” the virus. We hear it a lot. What exactly do you mean?

“Israel has done a lot, and much more than any other country, in terms of vaccination and protection. Yet we are hitting a glass ceiling. Close to 50% of teenagers are vaccinated, and if you convince other teens and some of the 10% of adults who aren’t vaccinated, I don’t think it’s going to make a dramatic effect on our experience with COVID, especially when dealing with a highly-contagious variant like the Delta strain.

“We don’t have treatments that are effective enough yet. We should be better at wearing masks indoors and at observing social distancing, but aside from that there isn’t much more we can do. We can’t go back to lockdown, this would be terrible for the economy, and we need to live with the virus. More and more people will be exposed to the virus, and hopefully with immunity building up, it will become an illness closer to how we think of flu. Our state of mind right now needs to be to learn to live with COVID-19 while keeping the spreading of the virus under control.”

An Israeli teenager receiving a COVID-19 vaccine in Jerusalem on July 8, 2021. (Olivier Fitoussi/Flash90)

Since the moment Israel started vaccinating, we’ve been discussing the relevance of the Israeli experience to the world. What is the relevance of Israel’s encounter with Delta to the rest of the world?

“What we are seeing is a lot of countries dealing with the Delta variant and cases are rising but we’re seeing a small rise in serious cases here by comparison. And for others, having a country to observe — Israel — where the majority of the population is covered with two doses of the vaccine, makes us more than interesting. It makes Israel the most appropriate country to study the effect of vaccines on the unfolding reality of COVID variants.”

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