Woodruff noted that she and her colleagues were using Excel spreadsheets to fashion together bookings for different agencies, made more complicated by the tiered system of priority for those eligible for the vaccines over the winter.

"What we really needed and what this portal has done is given us the capability to have a non-restrictive appointing platform that can be accessed from any network for patients to schedule," she said. "They don't have to have a (Common Access Card), they don't have to be on a military network. They can do it from their personal computers, their personal Wi-Fi. It has allowed us to maximize patient appointments - getting as many people through the door as we can.

Navy Master Chief Petty Officer Kenneth Puckett, senior enlisted leader at Naval Medical Readiness Training Unit in Groton, Connecticut, said his command was only in the initial weeks of the rollout of DAP, transitioning from the U.S. Fleet Forces mid-Atlantic region's Vaccine Tasking Order process. April 12 was Groton's first full day of use for the portal.

"On our end we did not have any bugs or issues with it," Puckett said. "Any first day jitters were based on communications, like instructions on the greeting page that weren't followed, but nothing inherent to the web site."

Groton capped its doses per day to 100 to start.

The sites are all centrally hosted on servers at Madigan.

"Nobody has to load anything at their hospital, or locally - we have it all here for them," Barnhill said.

The sites have unique landing pages that detail eligible patient groups and which vaccine is being used. These vary and are subject to change daily. The Dunham Army Health Clinic in Pennsylvania, for example, recently showed a week-by-week dose eligibility breakdown for April and May. Meanwhile, at seven sites on Okinawa, Japan, vaccines were already available for anyone 18 and over, with no medical condition required.

But the sites are otherwise uniform in their intuitive step-by-step list of pages, which lead the user to a calendar that outlines days with appointments. Once you click on an appointment time, a short questionnaire is filled out and one's request for an appointment is sent to the MTF.

As with any new software platform, the sites have not been without bugs from the admin side. Issues are brought to DHA's attention to work with the developers to make corrections, Woodruff said, adding that she's confident hurdles can be overcome quickly. Even with a few bugs, the portal is an invaluable tool where none existed before, she said.

Since last month, hundreds more sites have been fielded. Use of the system is not mandatory, but if a site chooses not to use DAP, it must use another DHA-approved documentation method. The DHA offers weekly DAP training sessions to demonstrate system functionality and to educate MTFs about system capabilities.

"It's pretty simple, pretty straightforward, easy to get into, easy to book," said Puckett.

The sites will be adaptable for other future uses.

"You can modify this for any immunization or appointment type, so, say for next fall and flu season, you could certainly (schedule) your flu shots through this (portal)," Barnhill explained. "Boosters for COVID vaccinations, we could add that in. School physicals...there's a lot of different things you can do with a web tool like this as far as setting people up for events and care."

The DAP is just one of the available paths to make a vaccine appointment. The Military Health System has several tools to help TRICARE beneficiaries and DOD community members schedule a COVID-19 vaccine appointment.