A Northern Illinois University professor of industrial and systems engineering says the country is facing many obstacles as it attempts to get Americans vaccinated.

Illinois is currently in Phase 1B of its vaccination plan, as frontline essential workers like police and fire personnel, teachers and child care workers, and manufacturing workers among others are able to get vaccinated. But everyone included in Phase 1A has not been vaccinated, as Walgreens and CVS Health attempt to get to residents in the state’s long-term care facilities. At this rate, it could be months before the average citizen gets a shot.