Interview

‘Bad omens’: Optimism over Israel’s child vaccine marred by COVID spike — expert

Top immunologist Cyrille Cohen reflects on the dosage, efficacy and timing of the shots being rolled out for kids

Nathan Jeffay

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

Professor Cyrille Cohen (courtesy of Professor Cyrille Cohen)
Professor Cyrille Cohen (courtesy of Professor Cyrille Cohen)

Israel started vaccinating children this week, in a move that experts hope will slam the brakes on a new rise in infection levels.

The country’s basic reproduction number, signifying the average number of people that each coronavirus patient infects, is now close to 1.1, which means cases are growing. It was below 1 — meaning cases were in decline — from early September until two weeks ago.

There has also been an increase in the proportion of tests that are returning positive, which is now around 1 percent.

“These are not good omens,” said Prof. Cyrille Cohen, head of the immunotherapy laboratory at Bar Ilan University, stressing that “things can deteriorate quickly.”

Cohen spoke with The Times of Israel on the current coronavirus situation and on the rollout of child vaccines, which he believes will “help minimize the next rise in cases.”

People in Israel are confused. On the one hand, people are feeling we’ve just beaten the fourth wave, and on the other hand, we’re being told about a rise in the reproduction number, which means that even though case numbers are still low, they seem to be on the rise. Are we on our way out of the pandemic, as many feel, or in a respite between waves, as many fear? 

I believe unfortunately that we are in a pause. COVID is not over. What exactly is in store for us right now depends on variants, the length of protection that the booster gives, and how many kids get vaccinated. In this regard, we have seen in the past months that children represent the majority of the daily infections, totaling more than 60%.

Children receive their first dose of COVID-19 vaccine, at a Clallit vaccine center in Jerusalem on November 23, 2021. (Olivier Fitoussi/Flash90)

So far, it has been very difficult to control the spread of infections among the young. With cases rising and the winter coming, I hope that vaccination may help minimize the next rise in cases. Still, I can’t say that I’m relaxed — not at all. Things can deteriorate quickly, as we learned, and we have to stay vigilant.

How concerned should we be that the reproduction number has risen above 1? What does it mean for us?

The reproduction number has steadily been going up for a week, reaching 1.08, and we see the positivity level of tests approaching 1%. These are not good omens. I don’t think this means necessarily a new wave, but even equilibrium in a pandemic involves small rises in cases — albeit, we hope, with less translation to severe cases than we’ve seen in the past thanks to the effect of booster shots.

Learning to live with COVID doesn’t mean having zero new cases a day, but rather understanding that things go up and down, and coping with the situation to minimize its impact on health and society.

The health minister, Nitzan Horowitz, The Health Minister of Israel, Nitzan Horowitz, suggested on Wednesday, amid discussions on rising cases, that Israelis may need to get a fourth COVID-19 vaccine dose. What do you think about this?  There is always a possibility that we will need further shots but it is a bit to early to tell. It really depends on several factors such as the effectiveness of the 3rd dose along time and the emergence of new variants. It could be that fourth shots, if they happen, will mainly be targeted to certain types of vulnerable populations. We still lack important information on how many times we will be able to safely use the same messenger RNA injections. So, I also think that we need to consider using other vaccines, ones that work with other types of vaccine to achieve broader immunity against SARS-CoV-2.”>suggested on Wednesday, amid discussions on rising cases, that Israelis may need to get a fourth COVID-19 vaccine dose. What do you think about this? 

There is always a possibility that we will need further shots, but it is a bit too early to tell. It really depends on several factors such as the effectiveness of the third dose over time and the emergence of new variants. It could be that fourth shots, if they happen, will mainly be targeted to certain types of vulnerable populations.

We still lack important information on how many times we will be able to safely use the same messenger RNA injections. So, I also think that we need to consider using other vaccines, ones that work with other types of technology to achieve broader immunity against SARS-CoV-2.

Health Minister Nitzan Horowitz speaks during a press conference near Tel Aviv, on November 9, 2021. (Avshalom Sassoni/Flash90)

The government pinned hopes on vaccines to deal with the fourth wave, and fared well, and now it’s looking to bolster protection via the newly launched shots for children aged 5 to 11. Do we expect different side effects for kids than adults? 

There could be some difference in side effects, but in general we don’t expect to see considerable differences as your immune system functions largely the same when you are 5 compared to when you are 14.

In biology we always have to be cautious, but that being said, most side effects are detected in a few weeks to a few months. There is no scientific basis to support the notion, or the fear, that something will pop up in a few years, for example the worry that in a few years people will have fertility issues.

People are talking a lot about possible side effects of vaccines but people aren’t talking about the ongoing effects of COVID that we already see — a range of manifestations of coronavirus, such as heart problems, lung problems and nervous system problems.

For children, a particular concern is that two to six weeks after COVID there can be PIMS — pediatric inflammatory multisystem syndrome — which is reminiscent of Kawasaki Disease. In Israel we’ve had almost 300 cases of COVID-related PIMS, including a fatality. This leads to hospitalization, gets children to a severe condition, and can be life threatening. It’s true that COVID is often asymptomatic for kids but parents should remember that it can lead to problems afterwards.

A woman brings her daughter to receive a coronavirus vaccine at Clalit Health services, at a makeshift vaccination center in the Cinema City complex in Jerusalem, on Nov. 23, 2021. (AP Photo/Maya Alleruzzo)

What have we learned from data or information coming from America about vaccination of under-12s that may be useful for Israeli parents to know? 

We don’t have precise data beyond the fact there were no reports of severe side effects like myocarditis [a condition that was seen in some adults and teenagers after vaccination], yet it takes time to process everything and establish clear links between vaccinations and any possible side effects, so it’s too early to draw detailed conclusions. It’ll be a few weeks before we have detailed data from the US.

Some parents will read what you said about it taking a few more weeks for detailed American data and wonder whether they should wait until then to vaccinate their kids. What do you say? 

This is understandable, especially as children are not considered a population at risk when it comes to the coronavirus. I understand the hesitation of parents and the desire to see more results. It’s not for me to say what anyone should do in this regard. Psychologically, a parent may think, “If I immunize my kid it may harm him or her so I won’t do it now.” But on the other hand, if there’s a surge in cases and you haven’t vaccinated, you may be putting your child at risk. Each parent should decide based on reliable information, and if relevant consult a pediatrician.

Should parents who do vaccinate expect their children to feel unwell after COVID vaccines?

Sometimes, though most of the side effects noted for children so far are things we knew about from adults: muscle pain, some fever and other things that are not serious.

A health worker prepares a COVID-19 vaccine in Jerusalem, on October 3, 2021. (Yonatan Sindel/Flash90)

How will the best interval between shots be decided for Israeli kids? What appears to be the optimum?

It will be three weeks after the initial shot, which was the timeframe in the trial, though there is an interesting discussion about the timing of follow-up shots.

We have seen studies around the world which indicate three weeks may not be best in terms of vaccine effectiveness and waiting eight weeks may be better. This was discovered by accident as some countries couldn’t deliver the second shot on time, and they started to see that eight weeks is the sweet spot in terms of vaccine effectiveness. This is great for times when there is a very low level of infection, but there are two reasons it’s unlikely Israel will adopt this.

Firstly, Israel is likely to want to go with the dosing protocol that was used in the trial, and in the trial of 5- to 11-year-olds it was three weeks. Secondly, in three weeks we expect cases to still be relatively low but we don’t know exactly what the level of cases will be and if numbers increase significantly we would wish we had administered follow-up shots more quickly.

Illustrative: Shaare Zedek hospital staff wear safety gear as they work in a coronavirus ward, in Jerusalem on September 23, 2021. (Yonatan Sindel/Flash90)

The new child doses are a third the size of adult doses. Some parents are bemused that on a child’s 12th birthday the size of the shot becomes much bigger. They wonder if the smaller shots are enough for a large 10-year-old or if the adult shots may be too big for a small 12-year-old.

There’s nothing unusual here, in the realm of medicine, in having a cutoff that means that a child born one day gets a smaller dose and a child born the next day gets a bigger dose. It’s very standard and very safe. In terms of this vaccine, the dosing is based on research. For 5- to 11-year-olds in Phase I clinical trial they tested three doses — 10, 20 and 30 micrograms, and they got a good response with 10 micrograms, which is the dose size being used.

A child of 12 and a day would also be fine with 10 micrograms, but as children get older they benefit from more. But parents of larger children aged just under 12 or smaller children in their early teens don’t need to worry — dosing has been calculated to be both effective and safe.

Let’s talk about misinformation. Michael Yeadon, a former VP at Pfizer, posted on Instagram, saying: “Children are 50 times more likely to be killed by the COVID vaccines than the virus itself.” Is there truth in this? 

He seems opposed to vaccination and has been making unfounded claims; I honestly don’t understand why he is making such claims and based on what. He’s the same person who said last October that the second wave in the UK would “fizzle out.” He also made claims that vaccines would cause infertility, which I think were based on incorrect understanding of the science behind vaccines. We have several studies showing there is no basis to these claims.

Microscopic view of a coronavirus variant, known as B.1.617.2 (iStock via Getty Images)

Returning to general COVID news, we’re hearing about several different variants that are on the rise, including AY.4.2 which is said to be more infectious and less symptomatic. What is on the horizon in terms of variants? 

AY.4.2 is on the rise, especially in the UK, accounting for 20% of the new cases in certain parts of England. It is a descendent of Delta and seems to be a little more infectious. The good news is that vaccines are effective in stopping it as it doesn’t evade antibodies, and that it doesn’t look like it will become dominant in Israel. Today, Delta remains the dominant strain. For now at least, it’s the devil we know.

We’ll soon enter 2022, which will be the fourth year tainted by COVID-19. Have you any reflections heading into the new year?

We are running a marathon against this disease. If 2019 was the year of its emergence, 2020 was the year of lockdowns and 2021 was the year of vaccines, I hope that 2022 will be the year of treatments, as these are needed to complement immunizations. This is especially important as we do not know yet how long booster shots will be effective and how many times we will be able to get them.

We might also need different types of vaccines such as nasal vaccines to better mimic COVID infection and provide a more effective long-lasting immunity. While several open questions remain and it is not over yet, I remain optimistic that we’ll learn how to live with COVID.

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