Mbala-Kingebeni P, Pratt C, Mutafali-Ruffin M, et al. - Diagnosis of EVD was made in a patient during the 2018–2020 Ebola virus disease (EVD) outbreak in North Kivu province in the Democratic Republic of Congo; this patient had received the recombinant vesicular stomatitis virus–based vaccine expressing a ZEBOV glycoprotein (rVSV-ZEBOV) (Merck). Ebola virus (EBOV)–specific monoclonal antibody (mAb114) was provided to treat him, and his recovery was recorded within 14 days. However, the patient revisited with severe EVD-like illness and EBOV viremia after 6 months, and died. In epidemiologic and genomic investigations, it was identified that the patient had had a relapse of acute EVD that resulted in a transmission chain leading to 91 cases across six health zones over 4 months. Findings highlight the necessity for more data to ascertain the mechanism and risk factors of EVD relapse in order to avert future transmission events and protect patients as well as their families and communities.