Can Missouri employers require their employees get a COVID-19 vaccine? Instead of a mandate, they might find more success with incentivizing the vaccination. Doctor giving a senior woman a vaccination. Virus protection. COVID-2019. Missouriâs COVID-19 vaccine rollout has been slowly unfolding, with vulnerable populations and essential workers only beginning to get inoculated. So far, registration has been voluntary, but the more people who are vaccinated, the safer it will be for workers and those with whom they interact. Itâs in the best interest of employers to make sure as many o...