"Eleven months after scientists the world over got their hands on the genetic sequence of the virus, we are seeing the beginning of the end of this pandemic," Gov. JB Pritzker said.
The vaccine arrived as Illinois public health officials reported 7,214 COVID-19 cases and 103 related deaths Monday. The total number of cases in Illinois now stands at 856,118, with a total of 14,394 deaths.
RAW VIDEO: First COVID-19 vaccines arrive in Illinois
The state's vaccination rollout began deliberately but very cautiously as Illinois received about half of its allotted 109,000 doses. The rest is expected to come later this week.
"Today is a very special day that should instill us all with optimism and hope," Gov. JB Pritzker said. "As of this morning the first shipment of the first FDA approved COVID-19 vaccine have arrived in Illinois."
WATCH: Gov. Pritzker discusses vaccine's arrival in Illinois
The governor himself was on hand to see the first shipments as they were unpacked from the dry ice shipping boxes and put into ultra-cold storage freezers at the state's undisclosed Strategic National Stockpile warehouse. From there, they will be shipped out to 10 regional hospitals around the state in Tuesday and Wednesday.
"As we speak, our vaccine distribution teams are putting into action. What they have prepared and drilled for over the past several weeks," Gov. Pritzker said.
CHICAGOLAND VACCINE GUIDE: See COVID-19 vaccine distribution plans for your area
Four counties are getting their own direct shipments of the vaccine from Pfizer: Lake, Cook, St. Clair and Madison counties, as well as the City of Chicago. Mayor Lori Lightfoot tweeted photos of the vaccine's arrival in Chicago late Monday night.
Tomorrow the first Chicagoans will be vaccinated. This is a moment for history and a moment of hope. pic.twitter.com/85TaTdpBwQ— Mayor Lori Lightfoot (@chicagosmayor) December 15, 2020
"We've focused on the 50 counties with the highest death per capita and the hospitals that are nearby, some of those counties, to make sure that we're covering them as best we can with this first shipment," Gov. Pritzker said.
On Tuesday, the first health care workers in the city of Chicago will get vaccinated at Loretto Hospital in the Austin neighborhood, a West Side community hit hard by the virus.
RELATED: Will a COVID vaccine prevent you from infecting others?
Vaccinations will be staggered to frontline workers over a period of several days to ensure that any of the mild side effects don't adversely impact critical health care workers.
"So maybe you wouldn't take everybody on the COVID floor and do them all at that same time in case you had a significant number of people that do need to take a day off and you wouldn't be without a workforce," said Illinois Director of Public Health Dr. Ngozi Ezike. "So that calculation has been done and I'm appreciating that that has been done."
Hospitals say they have carefully developed rollout plans to ensure operations are not disrupted.
"And we're committed to doing this right, the stakes are too high to rush through it," said A.J. Wilhelmi, president, Illinois Health and Hospital Association. "So hospitals will approach the vaccination process in a planned and orderly way."
The governor's office said the vaccine will be administered to healthcare workers at OSF St. Francis Medical Center in Peoria Tuesday morning.
RELATED: Illinois coronavirus testing: Where to get tested for COVID-19 in Illinois, Chicago area
Over a 24-hour period, officials said the state processed 92,256 specimens. In total there have been 11,869,088 specimens tested since the start of the pandemic in Illinois.
The preliminary seven-day statewide test positivity from Dec. 6-12 is 10.6%.
The test positivity rate is a metric the state began providing in late October. It is calculated by using the total number of positive tests over the total number of tests. This is the metric being used to by state health officials to make decisions about mitigations.
As of Sunday night, 4,951 people in Illinois were reported to be hospitalized with COVID-19. Of those, 1,070 patients were in the ICU with COVID-19 and 621 patients with COVID-19 were on ventilators.
Deaths reported Monday:
Boone County: 1 male 80s
- Cook County: 1 male 20s, 1 female 40s, 2 males 40s, 3 females 50s, 3 males 50s, 11 females 60s, 14 males 60s, 9 females 70s, 7 males 70s, 5 females 80s, 12 males 80s, 11 females 90s, 9 males 90s
- Fayette County: 1 female 80s
- Jackson County: 1 male 60s
- Kane County: 1 female 80s, 1 female 90s
- Lake County: 1 male 50s, 1 female 70s, 1 male 80s
- LaSalle County: 1 female 80s
- Mason County: 1 male 60s
- McHenry County: 1 female 90s
- Monroe County: 1 male 70s
- St. Clair County: 1 male 70s
- Wabash County: 1 female 80s
- Will County: 1 female 70s