The first shipment of a COVID-19 vaccine could be arriving in Alaska in just a few weeks, state health officials say.

The early batches of vaccine will be prioritized for essential workers in health care, assisted living and emergency medical settings, officials said Monday.

The mid-December timeline for vaccines is based on new announcements made by two drug companies — Pfizer and Moderna — who say their vaccines are more than 90 percent effective against COVID-19, a stunningly high effective rate for vaccines developed in record time, health officials say.

The high efficacy rates of these vaccines is “such a triumph,” said Joe McLaughlin, a state epidemiologist.

With these final bars left to clear, questions abound about who will get access to the vaccine and when, how safe it is, and how distribution could work in Alaska, a state with unique geographic challenges and limited health care access.

The state has not definitively decided a timetable for distributing the vaccine, but it will be done in phases, with front-line health care workers being prioritized for the first doses, said Tessa Walker Linderman, the co-lead with Alaska COVID Vaccine Task Force, during the Monday briefing.

The state does not know how much vaccine it will be receiving, and officials are currently planning for three different scenarios: one in which the state initially receives less than 5,000 doses; one around 10,000 doses; and one around 20,000.

A tight timeline for distribution — especially in the case of Pfizer vaccine, which must be stored at minus 70 degrees Celsius, and can then only be refrigerated for five days after it’s thawed — complicates things further, officials say.

“There are very few freezers in Alaska and across the country that have that capacity,” said Joe McLaughlin, an epidemiologist with the state health department.

State health officials said one of their main priorities is making sure rural Alaskans have equal and equitable access to a vaccine.

On both a federal and state level, conversations about equitable access to vaccine distribution are being had, she said.

A team of 40 people including state and Alaska Native Tribal Health Consortium representatives are working “around the clock” on plans to receive, distribute and administer the vaccine, Walker Linderman said.

Alaska has not yet decided which vaccine it will receive, but that will depend on which is ultimately determined to be safest and most effective, and which is logistically easiest for distribution in the state, McLaughlin said.

Liz Ohlsen, a physician with the state health department, said on a call late last week that although the development of a COVID-19 vaccine has moved much more quickly than is typical, neither drug companies have skipped any steps for their clinical trials.

The federal Centers for Disease Control and Prevention has also said that cost will not be an obstacle to getting the vaccine, and that supplies will be distributed by the federal government at no cost to enrolled COVID-19 vaccination providers.