Quynh Tran, a clinical pharmacist from The Public Health Commission Corps, prepares a vial of Moderna vaccine on Tuesday, April 13, 2021, at a mobile vaccination unit currently stationed at the Oxford Casino in Oxford. Credit: Andree Kehn / Sun Journal via AP

Maine public health officials on Thursday floated the possibility of offering coronavirus vaccines without appointments, which would make the vaccination effort more flexible but would pose logistical hurdles.

Appointments have been the only guaranteed way to get a shot in Maine so far, as supply has remained constrained despite increasing availability in recent weeks. State officials allowed providers to give doses to people outside the eligibility parameters when doses were limited to certain age ranges, but those were in rare cases where appointments were canceled or doses were left over.

Maine has given final doses to 36 percent of its population and nearly half have had their first doses, according to state data. But some are still struggling with accessing vaccines, particularly those in the newly-eligible under 50 category, who have been able to get doses since last Wednesday. Readers reported in a Bangor Daily News survey that finding appointments locally was among their biggest challenges in getting vaccinated.

Maine Center for Disease Control and Prevention Director Nirav Shah said the state is looking for ways to expand the availability of vaccines by discussing the possibility of adding early- and late-day appointments with providers. It is also in the “very preliminary” stage of exploring walk-up vaccine appointments, a process that would likely be shaped by the future of one-shot vaccines and providers’ flexibility.

“It’s not going to be for everyone, it’s not going to be everywhere, but there might be some locations in the state where there’s a higher degree of walkability, where having some degree of unscheduled hours is what makes it easier to get vaccinated,” Shah said.

In a tweet to a reporter after the briefing, Shah said morning walk-up appointments would likely reduce the chance of wasted doses. Unscheduled vaccine shots would almost certainly rely on the use of the Johnson & Johnson vaccine because of less strict storage and shipping requirements compared to the Pfizer and Moderna vaccines. Those two-doses require ultra-cold storage prior to use and cannot be re-stored if they are thawed.

However, the one-shot Johnson & Johnson option is currently not available after federal health agencies called for a pause on its use after six women among the millions to get the vaccine so far developed a rare blood clot after getting a dose. An advisory panel declined to make a decision on the vaccine’s future Wednesday, saying it needed to study the clots further.

Those kinds of walk-up clinics could also challenge providers. Many have diverted staff from various departments to support mass vaccination efforts. Walk-ups could be tricky to schedule for providers with two-shot vaccines since a person would still need to schedule a second dose within two to three weeks to get maximum immunity, said Charles Ouellette, who runs the St. John Valley Pharmacy in Fort Kent and co-owns Bangor Drug.

Because those doses need to be used once they are open, Ouellette said he would probably need to rely on a waitlist of people looking for doses to prevent waste. That could also be a challenge if demand begins to wane. But Shah’s idea sounded feasible, Ouellette said.

“If the state’s goal is to focus on inequity, then it could be a good solution — to just be able to get it whenever you want,” he said.