NAPLES, Italy — A team of Navy Seabees wrapping up its mission in Ebola-affected areas of West Africa will travel to the U.S. for a mandatory 21-day quarantine instead of returning to their base in Djibouti, according to several defense officials.

The 15-member engineering detail from Naval Mobile Construction Battalion 133 will most likely head to Langley Air Force Base in Virginia, according to the officials, who were aware of discussions but not authorized to speak about them. The Seabee team deployed from the Navy base at Camp Lemonnier, Djibouti, in September, to do surveying work for a series of Ebola treatment centers in Liberia.

Team members have not been in contact with anyone infected by Ebola and are not believed to be ill, officials said.

The Defense Department has mandated all servicemembers returning from Ebola zones under the military’s Operation United Assistance undergo a quarantine, which it calls a “monitoring regimen.” Military leaders are still hashing out details of the quarantine but have said troops will generally return to the bases from where they deployed. That poses a challenge for those deployed from overseas U.S. bases, with several host nations restricting entry to anyone coming from the region, including military personnel.

In addition to Langley, the Army base at Fort Bliss, Texas, is available for quarantine, according to one of the officials. Navy administrators will be on hand for the quarantine, with Army or Air Force medical personnel available if needed, depending on the base, the official said.

Twenty-one days is the maximum amount of time that can pass before someone infected with Ebola becomes symptomatic. The disease is spread only when a victim is symptomatic.

The group is the first from the Navy to return to the U.S. After the quarantine, members of the team will go where needed, including back to the base in Djibouti, the official said.

The same bases will be used for other naval personnel returning from the region, the official said. Among those deployed are members of a Navy mobile medical lab and medical personnel assigned to members of a Marine task force deployed out of Spain.

The military operation in West Africa is built around construction of 17 Ebola treatment centers with 100 beds each, as well as the creation of a logistical hub for medical supplies coming into the region and a training program for volunteer medical personnel.

Soldiers with the 101st Airborne Division are scheduled to deploy to the region as part of the operation, which military planners have said could last six months or longer.

A Pentagon spokesman said Tuesday that those plans remain in place despite a sharp decline in new infections in Liberia in recent weeks. The spokesman, Rear Adm. John Kirby, said Ebola infection rates have been known to rise and fall abruptly.

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