JERUSALEM -- The effectiveness of the Pfizer vaccine against the coronavirus has dropped to just 64 percent in Israel, the country's Ministry of Health said in a statement on Monday.

The new figure refers to the period between June 6 and July 3, and it is significantly lower than the effectiveness rate of 94.3 percent in protection against infection, measured between May 2 and June 5.

The ministry noted that the decline was observed along with the spread of the Delta COVID-19 variant in Israel.

However, the effectiveness of the vaccine in preventing hospitalizations and severe coronavirus disease is currently estimated at 93 percent in Israel, it added.

The ministry currently promotes the administration of a third vaccine dose to those who have suffered a functional decline in the immune system, but there is currently no decision to launch a third dose campaign for the entire population.

Since the start of the vaccination campaign in Israel on Dec 20, 2020, over 5.65 million people in Israel, or 60.6 percent of the population, have received the first dose of the vaccine, while 5.18 million have received the second dose.