Israel will add more countries, including the U.S., to its quarantine list.

Israel will add 18 countries, including the United States, to a list of locations from which travelers will need to quarantine after reaching Israeli soil, the Health Ministry said Tuesday. The requirement will come into force on Aug. 11.

Those affected include people who were vaccinated in Israel, or who have recovered from the coronavirus — none of whom were previously required to quarantine when traveling from the 18 countries.

The countries added to the list also include Germany, France, Italy and Greece.

Most studies indicate that immunity resulting from the vaccines made by Pfizer-BioNTech and Moderna is long-lasting, and researchers are still trying to interpret recent Israeli data suggesting a decline in efficacy of the Pfizer-BioNTech vaccine months after inoculation.

The additions to the list mean that travelers from more than 40 countries will now have to quarantine for up to 10 days after arriving in Israel, whether or not they were vaccinated.

Israel has been a greenhouse for antivirus measures since the start of the year, when the country became one of the fastest to fully vaccinate a majority of its population against the coronavirus.

Israeli society also returned far faster to normal life: By mid-June, the number of daily coronavirus infections had fallen to single figures and indoor mask mandates were lifted, as well as restrictions on gatherings and public events.

But an easing on inbound travel restrictions and the arrival of the Delta variant to Israel have contributed to a spike in infections since late June. In the past week, the average number of new infections each day rose beyond 2,400 — up from 300 at the start of July..