Healthcare workers (HCW) are defined as university employees working a healthcare setting who have the potential for direct or indirect exposure to patients, human research subjects or infectious materials including body substance, contaminated medical supplies, devices and equipment, surfaces, or air. HCW have specific health requirements that must be met prior to starting work, including MMR vaccine or immunity, varicella (chickenpox) vaccine or immunity, TB screening, COVID vaccine according to University policy, hepatitis B vaccine or immunity, and annual flu vaccination.