In Jesse McKittrick's line of work, the danger is usually pretty obvious.
But since the coronavirus pandemic began in March, that hasn't really been the case.
On every call for Frederick County Fire and Rescue, McKittrick and his colleagues have been wearing extra layers of personal protective equipment to shield themselves from an invisible, life-threatening enemy.
On Tuesday afternoon, McKittrick received yet another one, along with the peace of mind that it brings.
McKittrick, a 16-year veteran with Frederick County Fire and Rescue Services, was among the Frederick County first responders to receive the first injection of the two-dose COVID-19 vaccine from drug manufacturer Moderna.
The vaccinations were among the first to be administered by the Frederick County Health Department at one of its primary COVID-response sites, the Scott Key Center on Rocky Springs Road.
McKittrick's job brings him into potential contact with the virus on just about every shift, and he has been worried about bringing it home and spreading it around.
"For me personally, I have been stressing over it for sure," he said.
So, being among the first to receive the vaccine brought him "a lot of relief."
He figured that he and his colleagues would be near the front of the line, but guessed that it might be mid-January before they received it given the limited supply at the onset of the rollout.
The county health department was planning on running the first of its vaccine clinics for first responders — in this case for Frederick County Fire and Rescue personnel and for those administering the shots — from 1-3 p.m. on Wednesday. But after receiving the shipment of Moderna vaccine a day earlier than expected, they moved the timeline up by 24 hours and notified the fire department.
"People need it," Dr. Randall Culpepper, the deputy health officer for Frederick County, said on a day the county's seven-day, rolling positivity rate surpassed 10 percent for the first time since May 28 (10.44 percent).
It now stands at 10.74 percent after jumping nearly a full percentage point from the previous day (9.79 percent).
Culpepper said the health department is monitoring more than 30 "outbreaks" in the county and can't afford to wait to distribute the vaccine if there is enough supply.
There have been 10,891 confirmed cases of COVID-19 in Frederick County after another 103 were reported Tuesday. So far, 174 Frederick County residents have died from COVID-related health issues.
Culpepper said the county health department has received 1,500 doses of the vaccine thus far, a small number of which were used last week for a test run of Tuesday's clinic and then roughly 50 more at the clinic itself.
The county is being conservative in administering its initial doses of vaccine because it has to ensure it has enough when people come in for their second shot in a month, Culpepper said.
All of the vaccine the county health department has received so far has been from Moderna, which received emergency-use authorization from the Food and Drug Administration on Dec. 18. The vaccine was shown to have 94 percent efficacy and doesn't have to be stored at ultra-cold temperatures like the COVID-19 vaccine from Pfizer.
Frederick Health Hospital, which was treating more coronavirus patients Sunday (63) than at any other point of the pandemic, has been administering the Pfizer vaccine to its front-line health care workers since Dec. 17.
The Pfizer vaccine, which received FDA approval Dec. 11 after demonstrating 95 percent efficacy, requires two doses that are spaced three weeks apart, while the timeline stretches to four weeks for the Moderna vaccine.
First responders who received their first dose Tuesday from the county health department made their appointment for the second dose before they left.
It's unclear when the county health department will run another clinic for first responders because it depends on the size and timing of the vaccine shipments. But health department officials said there will likely be multiple clinics next week, with Monday being a probable date for the next one.
Culpepper estimated the vaccine will become available to the general public by the middle of March, but he cautioned that timeline could be a bit optimistic.
"I hope I am wrong," he said. "I am hoping it is sooner."