Those who received the second dose did not have any neutralization ability against the variant, while they continued to have some ability against Delta and even the original Wuhan strain.
“There was no neutralization ability whatsoever, and that is very worrisome,” said Dr. Gili Regev-Yochay, director of the Infectious Disease Epidemiology Unit at the hospital, in a briefing on Saturday night, adding that these people might also be exposed to serious disease. ...
On the other hand, the Sheba study found that the booster dose does increase the ability of the vaccine to work against Omicron by about 100-fold, meaning that there is “significant protection,” Regev Yochay said. “It is lower than the neutralizing ability against the Delta – about four times lower. But it is very optimistic.”
