Uncertainty surrounding vaccine shipments from the federal government is disrupting distribution of the COVID-19 vaccine at a time when the virus is surging in Maine and across the country, according to Maine’s top infectious disease expert and other officials around the nation.

Maine Center for Disease Control Director Dr. Nirav Shah said the Trump administration’s last-minute reduction in vaccine doses expected to arrive next week has delayed plans to begin vaccinating staff and residents in the state’s assisted-living facilities.

“We’d like to know if there are these types of expected shifts to be coming,” Shah said during a media briefing Friday. “That sadly and regrettably had implications for us. The state had to opt not to activate another phase” of its vaccine program.

It wasn’t clear Friday night how the U.S. Food and Drug Administration’s approval of an emergency use authorization for a second vaccine developed by Moderna Inc. and the National Institutes of Health would affect the delivery of vaccines to the state.

Along with confusion among state officials, there is currently no way for the public to track vaccine distribution by Operation Warp Speed, the Trump administration program tasked with expediting the development and distribution of COVID-19 vaccines. Neither the state nor the federal government has posted regular updates online with details about the numbers of doses delivered and administered. The state has issued media updates and Shah has provided some of that information in briefings this week. Maine’s CDC said Friday that an online dashboard with updates on the vaccine rollout is being developed but did not provide a time line.

Meanwhile, little information was made public this week about plans to begin vaccinations in Maine nursing homes, an effort that could begin as soon as Monday.

Frustration about the nation’s week-old vaccine rollout emerged around the country late this week when Operation Warp Speed informed states that vaccine shipments due next week would contain roughly 40 percent fewer doses than they had been told to expect. While Shah called for more stability in the vaccine rollout, some officials in other states were more outspoken.

“This is disruptive and frustrating,” Washington Gov. Jay Inslee, a Democrat, wrote on Twitter Thursday.

“To slash allocations for states – without any explanation whatsoever – is disruptive and baffling,” Nevada’s Democratic Gov. Steve Sisolak, said in a statement, The Associated Press reported.

In recent days, governors and health leaders in more than a dozen states have said the federal government told them that next week’s shipment of the Pfizer-BioNTech vaccine will be smaller than originally projected, AP said.

The cause of the reductions remained unclear Friday with federal officials saying the earlier numbers were projections and not promises, and that the states will eventually get their full allotments. Pfizer, the vaccine manufacturer, has said it has plenty of vaccine ready to be shipped.

Maine received its first allotment of the vaccine this week and doses were quickly administered to thousands of front-line health care workers at seven large hospitals.

As of 8:15 a.m. Friday, 2,264  people had received their initial dose of the vaccine, and hospitals were continuing to inoculate hundreds of people a day, Shah said. Those health care workers will get a second dose of the vaccine 21 days after the first.

Of the initial allotment of 12,675 doses, 5,850 were targeted for health care workers and 6,825 for residents and staff of nursing homes around the state. Maine and other states got an unexpected bonus in the first shipment because each vial contains an extra dose, translating to a 20 percent increase in doses and enough to vaccinate about 2,500 additional  people.

Maine has about 75,000 health care workers who have direct contact with patients and about 6,200 residents in skilled nursing homes.

Vaccinations of nursing home residents could begin as soon as Monday, but it was not clear Friday which facilities, if any, were prepared to start the program. Nursing homes were busy this week trying to get signed consent forms from patients or their families.

The federal government is working with commercial pharmacies to send teams into nursing homes to administer the vaccines.

A spokesperson for CVS Health confirmed teams for their pharmacies will begin holding clinics in skilled nursing facilities beginning Monday, but declined to provide details about which facilities they would be visiting or disclose how many doses they were planning to administer. The spokesperson also declined to answer whether CVS already had the doses or was awaiting their delivery.

“A handful of stores in Maine have been selected to store the vaccine for long-term care facility vaccinations based on their geographic proximity to those facilities,” said Mary Gattuso, senior manager of corporate communications. “Our pharmacy teams performing the vaccinations will pick up the vaccines from these stores on Monday on the way to their initial vaccination visits occurring that day. We are not disclosing specific quantities of vaccine being stored at these pharmacies.”

Gattuso said CVS would use a combination of dry ice and special storage containers developed by Pfizer to store the vaccine, which must be kept at minus 70 degrees Celsius (minus 94 degrees Fahrenheit). She referred a reporter to state officials for details about the amount of vaccines being allocated.

A spokesperson for the Maine Department of Health and Human Services said pharmacies are working directly with the U.S. Centers for Disease Control and Prevention so the state does not know where the vaccines were being stored and where they would be distributed.

A spokesperson for Walgreens said they would begin vaccinations at about 800 long-term care facilities in Maine and 11 other states starting on Monday, “including many in rural and urban medically underserved areas,” but also did not provide specifics.

Maine was planning to expand vaccinations to assisted-living facilities and other long-term care facilities beginning the week of Dec. 28, Shah said.

But  the state had to scale back those plans after being told Thursday it would only receive 8,775 doses next week, instead of the original estimate of 13,650, he said. Shah was unsure whether the state would receive additional vaccines during the next shipment, or whether the reduced amount would carry over to subsequent weeks.

“As a result in the reduction by Operation Warp Speed, we are delaying that start, which means some individuals and staff who live in assisted-living and other long-term care facilities may not start their vaccine clinics for another week,” Shah said. “We are hoping the subsequent week we will be able to activate it, although I can’t promise that, because we have not been given an estimate.”