Appointment scheduling has opened up for Connecticut residents ages 75 and older to receive the COVID-19 vaccine starting Monday — though they may have to wait for availability, and state officials are urging patience.

This kicks off Phase 1b of the vaccine rollout, which Gov. Ned Lamont announced Thursday also will include the groups that the allocation subcommittee of the state's COVID-19 Vaccine Advisory Group recommended Tuesday: people ages 65-74, those under 65 with underlying health conditions, residents and staff of congregate settings and front-line essential workers.

Deidre Gifford, acting commissioner of the state Department of Public Health, said Thursday that she started to see a drop-off in demand in Phase 1a, "and the governor's direction to us has been no appointments left unfilled, no shots left ungiven, so we quickly pivoted and started doing Phase 1b earlier than we thought."

There are three ways for those over 75 to schedule an appointment: online, over the phone, or directly through a provider.

"Don't just show up. That doesn't work. None of this Florida stuff," Lamont said in his briefing Thursday afternoon, as he was recovering at home from a hip replacement surgery Wednesday.

People can visit ct.gov/covidvaccine to access a form and schedule a time through the Vaccine Administration Management System. But the website cautioned Thursday, "Due to high traffic volume at websites and phone lines, eligible residents in Phase 1B may encounter delays scheduling appointments to receive the COVID-19 vaccine. Please try back later. Appointment availability is limited but we will continue to open up slots as they become available."

Those who don't have internet or face other barriers to self-scheduling can call Connecticut's COVID Vaccine Appointment Assistance Line, (877) 918-2224. Gifford said there's an option to hang up but get a call back, though she said DPH may not make all the calls back Thursday. She encouraged people running into technical issues to try back in a couple of hours.

Health care providers conducting vaccine clinics are in the process of reaching out to eligible residents, though the state urges people not to contact their physician or health care provider to set up an appointment.

Hartford HealthCare, the parent company of Backus Hospital in Norwich, noted on Facebook that it was experiencing heavy traffic on its website, and those eligible for the vaccine could schedule an appointment at mychartplus.org.

Those over 75 are among the estimated 1.3 million people eligible to receive the vaccine in Phase 1b. But the state currently expects to receive only 46,000 first doses per week. Lamont said coordination with the federal government has gotten a lot better in recent weeks, and he expects more clarity and a better sense of priorities after President-elect Joe Biden takes office.

Lamont has directed the Connecticut Department of Public Health to prioritize people over 75 within Phase 1b, the governor's office said in a news release.

The Lamont administration said as supply increases and a significant portion of those over 75 have received the vaccine, Phase 1b will open up to more people "with a focus on addressing issues of equity and risk of poor outcomes from COVID-19." Further guidance on when and how others eligible for vaccination in Phase 1b can schedule appointments is forthcoming.

The phase includes front-line essential workers in food and agriculture, education, manufacturing, corrections, public transit, grocery stores and the U.S. Postal Service. It also includes people in congregate settings, such as homeless shelters and correctional facilities, and those ages 65-74.

Gifford said vaccinations of people in congregate settings are happening parallel to the individual appointments, and they will be scheduled soon.

Lastly, it includes people with at least one of the conditions the Centers for Disease Control and Prevention lists as putting someone at increased risk of severe illness from the coronavirus.

Gifford said she couldn't give an answer yet to who, specifically, within Phase 1b would be phased in after those over 75. She also clarified that uncompensated caregivers aren't in Phase 1b unless they fit into another eligible category.

Nichelle Mullins, co-chair of the state's allocation subcommittee, said later that she believes uncompensated caregivers will be addressed at the group's next meeting. She also said the subcommittee will work with DPH to review the front-line essential worker list and will work on Phase 1c recommendations.

Latest case and vaccine numbers

From Wednesday to Thursday, 968 positive COVID-19 cases were reported from 22,171 tests, a 4.37% positivity rate, according to data from Lamont's office. To date, more than 4.8 million tests have been reported.

In those 24 hours, hospitalizations decreased by 30, bringing the total to 1,118, and 17 more people died, bringing total deaths from COVID-19 to 6,553. Locally, Lawrence + Memorial Hospital in New London said it was caring for 35 COVID-19 patients Thursday, while Westerly Hospital had seven.

Lamont said Connecticut is ranked fifth nationally in the number of people vaccinated per capita, and the state is getting an additional 50,000 doses next week from the federal government as a reward for its performance.

So far, 171,035 vaccine doses have been administered, including 16,041 second doses.

Benjamin Bechtolsheim, director of the COVID-19 vaccination program for DPH, provided more information in Thursday night's meeting of the state's COVID-19 Vaccine Advisory Group. He expects a "relatively large shipment" in the coming week that includes 100,000 first doses of vaccine but expects this to level off, though he hopes to be pleasantly surprised.

Bechtolsheim said if supply holds at the current rate of about 50,000 doses per week and the uptake rate is 75%, the state will be in Phase 1b through May. Gifford had noted in Lamont's briefing that her department has been saying all along that the general population can start getting vaccinated around early summer, and she doesn't think recent phase announcements and changes will impact that forecast much.

Bechtolsheim said of the doses that Connecticut had as of Sunday, 73% have been administered.

Day Staff Writer Brian Hallenbeck contributed to this report.

e.moser@theday.com