According to a nationwide serological survey conducted by the Israeli Health Ministry, SARS-CoV-2 antibodies are present in only 5.5 percent of the country’s population, far from the number required for “herd immunity” from the virus, the ministry announced on Thursday.
The survey, which was carried out between July and September in collaboration with Israel’s four health funds, examined 55,000 samples taken from across the country, according to a statement from the ministry. The study found antibodies present in 3.8 percent of those sampled (5.5 percent after equalizing variables to their values among the general population).
According to Health Minister Yuli Edelstein, “Israel is one of the first countries in the world to conduct serological coverage on a national scale and with such a wide range of subjects.”
The survey found that early 30 percent more men than women had antibodies present in their blood (4.9 percent vs. 3.1 percent), while the rate among children aged 10-18 was found to be 8.1 percent—the highest figure of all the groups sampled.
The geographical distribution of antibodies was also found to be uneven, with 9.5 percent of samples from the Jerusalem district testing positive, as opposed to 1.1 percent for the Haifa district. In the Tel Aviv region, the figure was 2.2 percent.
In “large” towns and cities (with more than 50,000 inhabitants) 4.3 percent of samples tested positive, while for medium and small towns the figures were 3.2 percent and 3.4 percent respectively.
In non-Jewish areas, antibodies were found in 2.1 percent of samples, as opposed to 3.6 percent for Jewish areas, while the rate in mixed-population areas was higher, at 5.5 percent. In haredi (ultra-Orthodox) towns and cities, the number of positive results was five times higher than in other areas.
The ministry statement stressed that the presence of antibodies does not necessarily indicate long-term immunity and reiterated the importance of wearing masks and adhering to social distancing directives, even for those with antibodies.
According to ministry data, of the 46,350 COVID-19 tests conducted on Wednesday, 8.9 percent were positive, marking this the first time the figure has dropped under 10 percent since the beginning of the nationwide lockdown on the eve of Rosh Hashanah. (The lockdown, the country’s second since April, was imposed on Sept. 18 but tightened significantly the following week as morbidity continued to rise.)
There has been cautious optimism in the country in recent days as the number of daily cases has continued to drop, indicating that the lockdown is beginning to have an effect. However, Coronavirus Project Coordinator Ronni Gamzu warned during an interview with Ynet on Wednesday that, paradoxically, the falling morbidity numbers themselves posed a risk.
“When the morbidity rate drops, even slightly,” said Gamzu, “there is less of a tendency [among the public] to get tested.”
He stressed that COVID-19 is largely asymptomatic, and that most of those with the disease are not aware of it, yet are still highly contagious. Anyone with even the slightest suspicion of having been exposed to the virus, he said, should get tested immediately, regardless of whether or not he feels sick.
The overall number of COVID-19 tests being carried out, he said, was still not high enough.
“I need [all of] Israel to go and get tested,” he said.
Prime Minister Benjamin Netanyahu said during a press conference on Tuesday that while there was cause for “cautious optimism,” he would not be rushing to lift the lockdown.
Also on Tuesday, the Israeli government extended by a week a law heavily restricting demonstrations and indoor prayers during the lockdown. The legislation, approved by the Constitution, Law and Justice Committee of the Knesset last week, will now remain in effect until at least Oct. 14.