Morbidity and Mortality Weekly Report 290 MMWR / February 25, 2022 / Vol. 71 / No. 8 US Department of Health and Human Services/Centers for Disease Control and Prevention Use of Ebola Vaccine: Expansion of Recommendations of the Advisory Committee on Immunization Practices To Include Two Additional Populations — United States, 2021 Jason H. Malenfant, MD1,2; Allison Joyce, MSc2; Mary J. Choi, MD2; Caitlin M. Cossaboom, DVM, PhD2; Amy N. Whitesell, MPH2; Brian H. Harcourt, PhD2; Robert L. Atmar, MD3; Julie M. Villanueva, PhD2; Beth P. Bell, MD4; Christine Hahn, MD5; Jamie Loehr, MD6; Richard T. Davey, MD7; Armand Sprecher, MD8; Colleen S. Kraft, MD9; Trevor Shoemaker, PhD2; Joel M. Montgomery, PhD2; Rita Helfand, MD2; Inger K. Damon, MD, PhD2; Sharon E. Frey, MD10; Wilbur H. Chen, MD11 Introduction On December 19, 2019, the Food and Drug Administration (FDA) approved rVSVΔG-ZEBOV-GP Ebola vaccine (ERVEBO, Merck) for the prevention of Ebola virus disease (EVD) caused by infection with Ebola virus, species Zaire ebolavirus, in adults aged ≥18 years. In February 2020, the Advisory Committee on Immunization Practices (ACIP) recommended preexposure vaccination with ERVEBO for adults aged ≥18 years in the United States who are at highest risk for potential occupational exposure to Ebola virus because they are responding to an outbreak of EVD, work as health care personnel at federally designated Ebola treatment centers in the United States, or work as laboratorians or other staff members at biosafety level 4 facilities in the United States (1). This policy note reviews the expansion of these recommendations to include two additional populations: 1) health care personnel* involved in the care and transport of patients with suspected or confirmed EVD at special pathogens treatment centers (SPTCs) and 2) laboratorians and support staff members at Laboratory Response Network (LRN) facilities that handle specimens that might contain replication-competent Ebola virus (species Zaire ebolavirus) in the United States. Background Ebola virus, species Zaire ebolavirus, is the most lethal of the four viruses that cause EVD in humans, with case fatality rates of 70%–90% when untreated (2). The virus is highly transmissible and can be found in all body fluids of an infected * Health care personnel refers to all paid and unpaid persons serving in health care settings who have the potential for direct or indirect exposure to patients or infectious materials, including body substances (e.g., blood, tissue, and specific body fluids); contaminated medical supplies, devices, and equipment; contaminated environmental surfaces; or contaminated air. These health care personnel include, but are not limited to, emergency medical service personnel, nurses, nursing assistants, physicians, technicians, clinical laboratory personnel, autopsy personnel, therapists, phlebotomists, pharmacists, students and trainees, contractual staff members not employed by the health care facility, and persons not directly involved in patient care, but who could be exposed to infectious agents that can be transmitted in the health