ByMAAYAN JAFFE-HOFFMAN

Israel has likely achieved herd immunity, health officials told The Jerusalem Post, after a summary of a new study by the Health Ministry revealed that 21% of children aged up to 16 have antibodies against the novel coronavirus.

Now, some health officials are questioning whether children really need to get the jab.

Herd immunity is achieved when, instead of spreading, a disease continually declines. Health officials believe that for a country to reach herd immunity, between 70% and 80% of the population would have to be vaccinated or have contracted the virus and developed antibodies.

“If you look at the reality in Israel, we have achieved actual herd immunity,” according to Prof. Dror Mevorach, a senior physician from Hadassah-University Medical Center.

Back in February, top Health Ministry officials believed that Israel would not reach herd immunity until the majority of its children were vaccinated against the virus.

“The moment we have 2.5 million children that can’t be vaccinated, we probably won’t reach herd immunity, even if the entire population that can be vaccinated, will be vaccinated,” said Head of Public Health Services Sharon Alroy-Preis at a Knesset hearing in February.

As such, when the government voted to allow youth to return to their classrooms in full after Passover, there was widespread belief by health experts that Israel would see a spike in infection.

“This did not happen. The only explanation is the achievement of herd immunity,” Mevorach said.

The Health Ministry study – a summary of which was viewed by the Post – was conducted in collaboration with the National Center for Disease Control and the Central Virology Laboratory. It showed that the prevalence of antibodies against the coronavirus was 21% in children 0-16 at the end of March 2021. It also found that the 12-15 age group had the highest rate of antibodies – 30%.

To conduct the test, some 2,700 serum samples from the appropriate age group were collected countrywide between January 2020 and March 2021.

With herd immunity achieved, the question arises as to whether or not the Health Ministry should backtrack on opening vaccination to children ages 12-15, especially given the vaccine’s potential link to heart inflammation in some young people.

“I am convinced that somewhere between one in 3,000 and one in 6,000 young adolescents – mainly males – will experience myocarditis,” Mevorach said. 
 
He stressed that “at the moment there is no clear need for vaccination,” but added that in the future there may be – especially for children who plan to leave Israel.
 
But Arnon Afek, associate director-general of Sheba Medical Center, disagrees.
 
“I personally think that we should vaccinate the kids,” he told the Post.
 
Cyrille Cohen, head of the immunotherapy laboratory at Bar-Ilan University, told the Post that just as adults who contracted coronavirus were encouraged to get vaccinated, it would not be a problem to inoculate children who had asymptomatic cases about which they did not know. He added, however, that because infection is low, parents who are hesitant to vaccinate their children could first request a serological test to evaluate if they already have immunity. He also pointed out that it is still unclear how long antibodies formed by somebody who had coronavirus last.
 
Cohen said while for most children coronavirus does not cause serious disease, “COVID-19 is not an easy disease for some kids.”
 
He noted that while the Health Ministry opened vaccination to children 12-15, it did not “recommend” it – except for those children who themselves are at high risk for serious disease, live with someone who is high risk or who plan to travel. Others, he said, should consider it with the advice of their doctors.
 
Finally, Mevorach said that even as Israelis remove their masks, they should stay alert for variants that could enter Israel and “start it all again.”
 
“Herd immunity is not necessarily forever,” he said.