All U.S. service members, even if they are fully vaccinated, are now required to wear masks indoors if they work at a military installation in an area where the novel coronavirus (COVID-19) is raging, the Defense Department announced on Wednesday.

For U.S. troops – many of whom thought the COVID-19 pandemic was over – that means wearing a mask while working again – and just in time for the hottest month of the year.

Service members can check on the CDC’s Covid Data Tracker website to see if they work at a military installation in an area where the risk of getting COVID-19 is high enough that they are required to wear masks while indoors, Deputy Defense Secretary Kathleen Hicks wrote in a memo on Wednesday.

This latest move also applies to federal employees, contractors, and visitors on Defense Department installations, Hicks wrote. All Defense Department facilities and other workplaces must post signs as quickly as possible to let people know what the local mask policy is.

US military COVID-19 Vaccine
Airmen from Team Fairchild’s 384th Air Refueling Squadron pose for a photo after receiving the Pfizer-BioNTech COVID-19 vaccine at Fairchild Air Force Base, Washington, Jan. 21, 2021. The first batch of the vaccine arrived to the 92nd Medical Group Jan. 15 to be distributed to Airmen and retirees. (U.S. Air Force photo by Airman 1st Class Kiaundra Miller)

Back in May, the Pentagon announced that troops would no longer be required to wear masks indoors on Defense Department installations if they had been fully vaccinated. But since then, the highly transmissible Delta variant of COVID-19 has exploded in areas where few Americans are vaccinated – and it even poses a threat to people who are fully vaccinated.

That prompted the U.S. Centers for Disease Control and Prevention to recommend on Tuesday that fully vaccinated Americans wear masks while indoors again if they live in a part of the country with a “substantial or high community transmission” of COVID-19.

Troops, Defense Department employees, and others who are not yet vaccinated must continue to practice social distancing, Hicks wrote in her memo.

United States photo

As of July 28, a total of 1,027,730 active-duty, National Guard, and reserve service members had been fully vaccinated: 363,626 soldiers, 106,754 Marines, 280,447 sailors, and 276,903 airmen and Guardians, according to the Defense Department. That is roughly 48% of all 2,139,669 active-duty, National Guard, and Reserve service members.

Another 233,565 troops have been partially vaccinated: 169,737 soldiers, 14,696 Marines, 21,588 sailors, and 27,544 airmen and Guardians.

Also, a total of 34,471 active-duty and reserve Coast Guardsmen have been fully vaccinated and that represents 70.4% of the total force, said Coast Guard spokeswoman Lt. Cmdr. Brittany Panetta.

News of the renewed mask requirement came on the same day that the Navy announced two sailors had died of COVID-19: Capt. Corby Ropp, 48, the department head of ophthalmology and refractive surgery at Navy Medicine Readiness and Training Command in Camp Lejeune, North Carolina; and Master-at-Arms First Class Allen Hillman, 47, who was assigned to Navy Reserve Volunteer Training Unit in Boise, Idaho.

CORRECTION: This story was corrected on July 29 to include the most recent numbers of all active-duty, National Guard, and Reserve service members.

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