The federal COVID-19 vaccine-finding website President Joe Biden promised last week will be an expansion of VaccineFinder, a website first created during the 2009 swine flu outbreaks to help people locate vaccine providers. On or before May 1st, the website should include information on every COVID-19 vaccine administration site in the country.

“It’s going to be an improved, federal version of VaccineFinder,” says John Brownstein, chief innovation officer at Boston Children’s Hospital and founder of VaccineFinder.

Over the past decade, VaccineFinder compiled information from around the country, showing people where they could find flu shots and other routine vaccines. It runs out of Boston Children’s Hospital in partnership with the Centers for Disease Control and Prevention (CDC).

It has been a part of the CDC’s COVID-19 vaccination plans since last fall. The back-end system is how the agency tracks the number of doses available at every pharmacy, clinic, hospital, or pop-up site administering vaccines. “Every COVID vaccine provider has had to register with us,” Brownstein says. Sites are asked to report the doses on hand every day.

“The platform itself is collecting data on daily inventory, all the different providers, and then feeding that information back to CDC,” he says. “This is one node in that whole flow of information.”

At the end of February, it launched a public-facing map showing vaccine stock at just under 30,000 providers across the country. It covers every pharmacy in the country giving vaccinations as part of the federal retail pharmacy program and additional locations in a handful of states, including Alaska, Indiana, Iowa, and Tennessee. Features directing people to non-COVID-19 vaccines are now offline.

Information from VaccineFinder is also now integrated into Apple Maps and Facebook’s COVID Information Center.

Over the next few weeks, more providers in more states will flip their vaccine supply information over to the public side of VaccineFinder. “That’s a state decision, of when they want to go public. You want to make sure the timing is right,” Brownstein says.

The team is also working to integrate appointment availability, not just vaccine supply, into the tool. Right now, visitors to the site will see if a location has vaccines in stock and which type of vaccine it has. That doesn’t necessarily mean a site has available appointments for those in-stock doses — people have to click out to the location’s own website to check that.

It’s not clear yet if and how people will be able to make appointments directly on the site, instead of having to click out to a site’s own scheduler. “We’re still working through exactly what that would look like,” Brownstein says. “Even right now, the feedback we’re getting has been overwhelmingly positive because it gives people a navigation tool, and a jumping-off point to book an appointment.”

The team is also working to improve the site’s accessibility, Brownstein says. They recently partnered with Univision to make it available in Spanish.

The absence of centralized resources to help people track COVID-19 vaccine availability has been a clear gap through the first few months of the US vaccination campaign. In most states, people eligible for vaccination have to bounce around between multiple registration websites for various sites to find open slots. Volunteers built makeshift aggregators in places like New York City to fill the gap. It has been great to see that innovation, and those tools have been useful solutions, Brownstein says. One benefit to VaccineFinder, he says, is that it has direct access to supply data from vaccination sites. “But we’re happy that there’s an ecosystem.”

Over the past year, state and federal governments have announced multiple tech solutions to various pandemic-related challenges. Many didn’t live up to the promises. In March 2020, former President Donald Trump announced plans for a nationwide testing website that didn’t exist. The website never materialized. A data system to help the states schedule and administer vaccine appointments was abandoned by many after it proved to be unreliable and buggy.

When launching a new tool, there’s always the worry that something might go wrong, Brownstein says. But because VaccineFinder has existed for years and is scaling gradually; he’s confident that it’ll work out. “We’ve already been rolling out this tool, it’s growing its user base, and the feedback has been positive — so we’re optimistic.”