Covid-19 vaccinations for Islanders 75 and over are set to begin Monday, Feb. 1, hospital officials confirmed Wednesday, although widespread questions and confusion remain regarding the logistics, signup process and timeline for the state’s slow-moving phase two vaccination rollout.

Phase two includes people over the age of 75, those with two or more underlying health conditions, then people over the age of 65.

At a press briefing Wednesday morning, hospital CEO Denise Schepici and operations chief Claire Seguin said the hospital had received 370 doses of the Pfizer vaccine from the state that they will administer in three clinics, beginning Monday and running through Wednesday and Thursday of next week.

The clinics will mark the beginning of the second phase of the state’s vaccination rollout on the Island.

But because the hospital has identified approximately 5,000 Islanders who fit in the first three categories of phase two and are eligible for the vaccine, officials said they would be prioritizing vaccinations for those over 75 with serious health risks, such as recent transplant and dialysis patients.

“It’s all based on medical condition,” Ms. Seguin said. “So we are prioritizing based on those categories that we talked about: over 75, and with co-morbidities.”

The hospital has scheduled 20 such patients for vaccinations on Monday, according to Ms. Seguin, and plan to schedule more in the upcoming days. No timeline was provided for a broader phase two vaccination rollout or a plan to get the other approximately 4,500 eligible patients — most of whom are healthy — vaccinated.

“There are all kinds of downward pressures trying to get vaccines into the state,” Ms. Schepici explained. “There is a production issue right now just coming from suppliers . . . I wish I had a timeline, but I just don’t.”

The current 5,000 eligibility estimate was derived from pulling hospital medical records for patients on the Island over the past three years, officials said.

To schedule an appointment for a vaccine, all patients, whether currently eligible or not, must follow registration protocol through either the hospital’s online portal, or the state Department of Public Health website.

Hospital patients and others who use Patient Gateway — the online scheduling portal used by the Mass General-Brigham hospital system — will be contacted directly by email to schedule a vaccine if they are eligible, according to Wednesday’s briefing.

All other Islanders are eligible to register for the vaccine and fill out an “attestation form” describing their health conditions, occupation and age through the state Department of Public Health website. Islanders should then forward that form's confirmation email to mvhinnovations@partners.org.

Hospital officials said they would pool those forms with current patient information to schedule the most high-risk patients.

The phase two attestation form went live late Wednesday morning, although news reports from around the commonwealth described a backlogged and challenging registration process. Hospital officials said the remaining 370 vaccines that arrived this week would be scheduled within the next couple of days, according to Ms. Seguin.

“Patients who meet those high-risk categories will be notified, either by phone or by Gateway, or as they tell us through that alternative process for nonpatients at the hospital,” Ms. Seguin said. “So they’ll hear soon.”

Ms. Schepici further explained the prioritization process.

“There are behind the scenes algorithms,” she said. “When Claire says it’s stratified by risk, there are things like cancer patients, immunosuppressed patients, transplant patients, dialysis patients, they kind of hit the top of the list, whether they were hospital patients or not. That’s how they get sort of generated and stratified. We wish we could do all 5,000 as quickly as possible, but like Claire said, we’re limited by the amount of [vaccine supplies] we’re getting.”

An infographic provided by the hospital Wednesday outlines the steps necessary for Islanders to sign up for the vaccine, either through Patient Gateway or the state website at mass.gov. The cost of the vaccine is covered for all recipients regardless of whether they have insurance.

Ms. Schepici said the hospital is prepared to administer 500 vaccinations a day through clinics when more supply becomes available, but is waiting on larger shipments from the state.

“Here at Martha’s Vineyard Hospital, we’ve kind of got this down now,” she said. “The clinic at the hospital has been very, very active.”

Ms. Seguin said the hospital’s phase one vaccination process went smoothly. Since mid-December, the hospital has vaccinated approximately 1,000 high-priority individuals. They include 432 health care workers at the hospital, all Windemere nursing home residents and staff, and 298 first responders in all six Island departments. Edgartown jail inmates have also been vaccinated, as well as courthouse safety officials and 100 additional community health providers scheduled for Wednesday.

Ms. Schepici estimated that there were approximately 1,200 total Island residents eligible in the first phase of the state’s vaccine rollout, of which almost all had received vaccines. They also said that more than 200 hospital staff have received the second dose of the vaccine.

But for the rest of the Island, Ms. Schepici urged calm as the hospital awaits more information — and vaccine shipments — from the state. She said the hospital had been inundated with phone calls and emails inquiring about the signup process.

“We are urging patience,” Ms. Schepici said. “I know everybody wants this as soon as possible. We do too. That’s why we are urging people just to check the website. We’re trying to make the instructions as simple as possible.”

Meanwhile, the Covid-19 virus continues to spread at an alarming rate on the Island. Hospital officials said there are currently two patients hospitalized, including a new admission. The patients are in good to fair condition, according to Ms. Seguin.

According to a New York Times county-by-county analysis published on its website Wednesday morning, Dukes County is at extremely high risk for Covid-19 — the highest possible rate in the country.

Ms. Schepici noted that a highly contagious variant of the virus had been detected in the commonwealth.

“As the vaccine rollout continues, which does give us hope and light at the end of this awfully dark tunnel, we can’t become complacent in our efforts to stop the spread,” she said.