Acting Secretary of Defense Christopher Miller visited Tripler Army Medical Center Wednesday for a briefing on the upcoming COVID-19 vaccination process for the military in Hawaii, including the hospital’s cold storage capabilities for the Pfizer vaccine.

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Miller was on a trip to Indonesia, the Philippines and Hawaii with a scheduled stop at U.S. Indo-Pacific Command headquarters at Camp H.M. Smith.

A Food and Drug Administration advisory panel today recommended widespread use of the first coronavirus vaccine in the United States made by Pfizer Inc. and BioNTech SE. Emergency use authorization from the FDA could come Friday.

Tripler was selected as one of 16 sites for a “controlled pilot” program for the first vaccinations within what the Defense Department is calling a phased approach.

“In the coming days, we expect the department to receive its first allotment of the vaccine,” Thomas McCaffery, assistant secretary of defense for health affairs, said at a press briefing Wednesday.

The Defense Department is expected to receive just under 44,000 doses of the Pfizer vaccine as early as next week for immediate use, McCaffery said.

“Our deliberate and phased approach to distribute and administer this first allotment and future allocations of the COVID-19 vaccine will focus on vaccinating priority populations quickly and safely,” he said.

The distribution of about 44,000 doses spread among 16 sites represents the first of two injections needed, officials said.

As soon as the FDA issues an emergency use authorization, the Defense Department’s allocation “will be pre-positioned at our initial locations,” McCaffery said. Upon issuance of the EUA, the Center for Disease Control and Prevention’s Advisory Committee on Immunization Practices will meet, review the EUA and then vote to recommend the vaccine, McCaffery said.

“We expect to have shots in arms of DOD personnel within 24 to 48 hours from the time” the advisory committee issues its final recommendation, he said.

Because the approval will be emergency use authorization, and not a fully-licensed FDA vaccination, the Defense Department’s policy initially will be the vaccine is voluntary.

“The department is strongly encouraging everyone to take it,” Lt. Gen. Ronald Place, director of the Defense Health Agency, said at Wednesday’s news conference.

Assuming the vaccine becomes fully licensed, the Pentagon at that point would make a determination whether the vaccine will be mandatory, McCaffery said.

The pilot vaccination at 12 continental and 4 off-continental sites — Hawaii included — “is to demonstrate that the process that we’ve developed actually works,” Place said. “Once we validate it, this controlled pilot, we have really scores of sites, hundreds of sites across the country and across the world” that will receive the vaccine.

The vaccine goes out in batches of 975 doses. Tripler, servicing a larger population, will get a larger allotment than some smaller sites.

The “very, very top priority” in the initial phase is going to be health care workers, McCaffery said. Also at the top will be emergency responders and public security.

Beyond uniformed military members, the criteria for dependents and some contractors and civilian employees will be related to “how do they match up in terms of the prioritization tiers,” McCaffery said. For dependents, the Defense Department will look at whether a person is a high-risk individual or part of the regular healthy population.

McCaffery said the Pentagon plans as part of the initial vaccination of health care workers and others to have “a very small set of visible senior leaders that will volunteer to take the vaccine” and do it in a public way to promote a message of safety and efficacy.

Pentagon spokesman Jonathan Rath Hoffman said although Miller, the acting secretary of defense, was visiting Tripler, he would not be getting vaccinated there.

Miller was appointed in the acting role Nov. 9 after President Donald Trump fired Defense Secretary Mark Esper.

In a visit to the Philippines on Tuesday, Miller met with Philippine Secretary of National Defense Delfin Lorenzana and Secretary of Foreign Affairs Teodoro Locsin.

While in Manila, Miller announced the recent transfer of $29.3 million in defense articles, including sniper and anti-improvised explosive device equipment, to senior Philippine military officials.

“This visit demonstrates the longstanding and steadfast U.S. military commitment to the Philippines, the oldest U.S. treaty ally in Asia,” the U.S. Embassy in the Philippines said.