Employees in health care and other high-risk environments face long-standing infectious disease hazards such as tuberculosis (TB), varicella disease (chickenpox, shingles), and measles, as well as new and emerging infectious disease threats, such as Severe Acute Respiratory Syndrome (SARS), the 2019 Novel Coronavirus (COVID-19), and pandemic influenza. Health care workers and workers in related occupations, or who are exposed in other high-risk environments, are at increased risk of contracting TB, SARS, Methicillin-Resistant Staphylococcus Aureus (MRSA), COVID-19, and other infectious diseases that can be transmitted through a variety of exposure routes. OSHA is examining regulatory alternatives for control measures to protect employees from infectious disease exposures to pathogens that can cause significant disease. Workplaces where such control measures might be necessary include: health care, emergency response, correctional facilities, homeless shelters, drug treatment programs, and other occupational settings where employees can be at increased risk of exposure to potentially infectious people. A standard could also apply to laboratories, which handle materials that may be a source of pathogens, and to pathologists, coroners' offices, medical examiners, and mortuaries.