People who haven't been able to secure appointments for a coronavirus vaccine are turning to Facebook groups and other online forums to find cancelled slots, figure out where to go, or simply to find information local health authorities have not provided.

Why it matters: These ad-hoc online communities have helped people get vaccinated and helped keep doses of the vaccine from going to waste. But they also underscore the confusion and frustration of the U.S. vaccine rollout, and the risk of misinformation is real.

The big picture: "We're a very entrepreneurial country, and using social media to advertise opportunities for vaccination is a good thing. It picks up where our government is not doing an adequate job," said Karl Minges, a professor in the school of health sciences at the University of New Haven.

• "Word of mouth has an important role, but you have to tread lightly with what kind of information you're putting out there," he said.

What's happening: Facebook pages and Reddit threads are emerging all over the country, filled with posts from people seeking vaccines or who have information about vaccine appointments.

• Los Angeles Covid Vaccine Hunters, a private page modeled after a similar one in New Orleans, has about 2,000 members, and aims to connect young people to vaccine doses set to be thrown out or expire.
• Maryland Vaccine Hunters, with 16,200 members, also helps people find unused doses. And it connects tech-savvy younger people with seniors, to help them schedule appointments.
• The Getting Pittsburgh Vaccinated group has more than 18,000 members, who have recently been discussing how to transfer appointments and lamenting the fact that some people are charging for their help.
• A Florida nurse and elementary school principal started South Florida Covid Vaccination Info, which now has 27,200 members and helps seniors with appointment booking.
• VaccineHunter.org organizes the dozens of "vaccine hunting" pages into one spot. On Reddit, r/VaccineHunters, along with related groups across the country, are highly active forums.

Yes, but: The potential for scams and misinformation is high, despite people's best intentions to help one another.

• This is particularly worrisome for high-risk populations, such as elderly people, who are not as savvy about identifying misinformation online and are more likely to fall for scams, Minges said.
• Facebook recently announced new moves to fight misinformation about theCOVID-19 vaccines. And it enforces its content moderation rules in private groups, though that can be tricky at scale.
• There is also criticism that such "vaccine hunters" are gaming the system or skipping the line ahead of people who are higher priority for the shots.

"I think these groups have been incredibly useful," said Jennifer Golbeck, a professor in the College of Information Studies at the University of Maryland. "There's always a risk of mis- or disinformation getting in there, but in these community groups, that tends to get shut down pretty quickly; the self-policing has been good."

• Still, she said, it's "really sad that you have to go to a social media forum to figure out this process."

The bottom line: "If there had been a good official system, there would not have been a need for this," said Awi Federgruen, a professor and supply chain expert at Columbia Business School. "It's an unfortunate development."