The report, published by the healthcare provider Leumit, comes on the heels of other Israeli studies that suggest a decreasing vaccine effectiveness, partly as a result of the Delta variant and partly because of the passage of time. However, British data indicates the Israeli studies may be overstating the case.

Data released by the Health Ministry on Thursday suggested that people vaccinated in January were said to have just 16% protection against infection now, while in those vaccinated in April the effectiveness was at 75%.
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"In a previous analysis we showed that as time passes since the vaccine, the level of antibodies drops at a rate of about 40% per month. This new study builds a clearer picture of the effect seen in the months after vaccination," said Shenhar.