Staff photo by Troy Stolt / LPN Adrian Price prepares a dose of the Moderna COVID-19 vaccine at the Hamilton County Health Department's COVID Vaccination POD at the CARTA Bus Terminal on Thursday, Jan. 28, 2021, in Chattanooga, Tenn.

Note: This story was updated at 1:25 p.m. on Feb. 14 to reflect new information from Hamilton County about whether it gives second vaccine doses to people who received a first dose elsewhere.

The continued high demand for COVID-19 vaccines in Hamilton County is a sign the area will not soon be expanding eligibility, despite calls from some area workers to include them in the line.

Bill Christian, associate director in the Tennessee Department of Health's Office of Communications, confirmed Friday the state determines when to change phases based on expected supply of vaccine and local demand.

"When there are vaccines available and no one is coming to receive them, it's time to move to the next phase," Christian said in an email.

Appointments for first doses of the two available COVID-19 vaccines continue to be filled in Hamilton County, even as the county is receiving more doses each week and announced an additional vaccination site Wednesday.

The high demand locally is also due, in part, to the county's decision last week to expand the age eligibility from age 75 and older to age 70 and older last week. The move, which county officials said better puts Hamilton in line with the eligibility of surrounding counties, added around 16,200 people to the approximately 26,500 people ages 75 and older in the county. This is in addition to the thousands of people eligible for the vaccine because of their employment.

As of Wednesday, the county had given doses to 39,092 county residents and 10,133 people living outside the county, which may include people who work inside Hamilton County and would therefore be eligible to receive a dose here.

Becky Barnes, administrator for the county health department, said her organization will continue to follow guidance from the state on changing phases. Tennessee's metro counties were granted permission to determine their own phases but Barnes said moving together decreases misunderstandings or confusion among residents.

(READ MORE: Hamilton County's COVID-19 vaccine demographics may not match census data, but experts say there are ways to ensure equity)

Local teachers are voicing concerns about not being eligible to receive doses in the county as local schools expand in-person learning after months of mixing online and in-person instruction.

Local educators announced a petition this week for the county to include them in vaccinations. The president of the local teachers union told the Times Free Press she started it when teachers told her they were taking sick days and traveling to other counties and Georgia to be vaccinated.

Teachers are included in phase 1b under Tennessee's vaccination plan and are expected to begin receiving doses later in February or in March, according to projections from the state. As of Friday, none of the counties immediately surrounding Hamilton County were in phase 1b, according to the state's phase chart.

The varied phases across the state have prompted some residents to seek vaccines elsewhere.

The Hamilton County Health Department does not provide second doses to people who jump phases and receive their first dose in another county or state because they are eligible there.

However, the department will provide second doses to people who move into the county or whose employment changed between their shots. In these instances, individuals must have their immunization card or be in Tennessee's registration system so the health department can verify they are receiving the second dose on the correct day. 

Dr. Lisa Piercey, commissioner of the Tennessee Department of Health, cautioned people from being frustrated when nearby counties announce new eligibility for groups or age brackets.

Moving slower with the current phases is a sign for a county that there is high local demand and a greater percentage of the people in each phase or age bracket are receiving a vaccine, Piercey said during a Wednesday news conference.

Contact Wyatt Massey at or 423-757-6249. Follow him on Twitter @news4mass.