More than 1,000 people lined up at the health district’s COVID-19 vaccination clinic this week after they were mistakenly allowed to book appointments for their first dose of vaccine.

Most of the people who booked appointments Wednesday were not supposed to be eligible yet for vaccination under the Blue Ridge Health District’s priority schedule — and when they arrived, many were turned away.

The issue was a technical one that remains unresolved.

The online appointment scheduling program available to Virginia health districts, called PrepMod, “does not have secure registration links,” said Ruth Morrison, the Phase 1B vaccine lead for the Richmond-Henrico Health District. “By that, I mean, if I send you a link to register, that link is shareable. So, it can traffic the entire internet.”

And anyone who gets that link can make an appointment.

Since the Virginia Health Department launched the new online registration system at the end of January, health districts across the state have reported similar problems of non-priority people getting a shared link and booking appointments.

On Feb. 4, a vaccination clinic in Norfolk was inundated with hundreds of people who had registered using a “leaked” PrepMod link. Health officials turned them away. A week later, there was a similar scene in the Chesapeake Health Department, after a PrepMod link was posted to the social media site Nextdoor.

“This has been such an area of frustration for so many of our providers, so many of our health departments that are trying to get vaccination events off the ground,” Dr. Danny TK Avula, the state’s vaccine coordinator, said at a news conference Friday. “I think this specific issue of links that can be shared and signed up by people they’re not intended for has been highly problematic for security issues at certain events.”

The state is working with PrepMod on a way to “fix” the link sharing issue, Avula said, adding that the issue will likely be resolved by the “end of next week.”

In the meantime, it’s up to individual health districts to manage vaccination clinics with the existing software.

Following the overrun on Wednesday’s BRHD vaccination clinic in the old Kmart parking lot off Hydraulic Road, health department’s “leadership team participated in a two-hour mediated After Action Review meeting … to discuss [the] clinic, how to avoid repeating mistakes, and how to improve our operations moving forward,” the district said in a statement.

Until the issue is resolved, the district may simply stop sending registration links altogether, and instead schedule appointments directly with eligible people over the phone or via email, a district spokeswoman said in an email.

Other districts have opted for similar workarounds. In Richmond, health officials are directly scheduling some appointments, and using a different online scheduling software system that can send private links for others. The problem with that is it requires staff to manually re-enter all the data collected from that software system into PrepMod, Morrison said.

Both methods are hugely time consuming, she said.

“This is what happens when you hand your health department butter knives and tell them to do surgery,” Morrison said. “This isn’t that hard if we were just handed the right tools, and these tools exist. But Blue Ridge Health District has not been given those tools. Richmond Health District has not been given those tools. The reality is, on the ground, until solutions are delivered, this is what it looks like. It looks like a lot of manual effort, a lot of confusion and unscalable systems.”