Background:Secondary transmission of Lassa fever (LF) occurs in the community and in health-care facilities, and is associated with high fatality in Nigeria. We investigated the role of oral ribavirin postexposure prophylaxis (orPEP) in preventing LF among the primary contacts of confirmed cases from December 2015 to March 2016.Materials and Methods:Epidemiological and clinical data of LF contacts were prospectively collected. However, information regarding ribavirin adverse effects (AEs) were collected retrospectively through a telephone interview. High-risk contacts were clinically monitored ΁ orPEP.Results:Thirty-five (94.6%) out of the 37 individuals enrolled in the study were contacts of confirmed LF cases, and friends and family members (54%) constituted the largest group. However, only 29 (83%) individuals were classified as high-risk contacts. Twenty-one (60%) of contacts were prescribed ribavirin with 6 (28.6%) of them reporting AEs. Body weakness (33%) was the most frequent AE, but there was no incidence of treatment discontinuation due to AE. Furthermore, there were no reported cases of LF among all respondents (0%), whether they had orPEP or not.Conclusion:Secondary transmission of LF seems uncommon and the benefit of orPEP is uncertain. Although AEs of ribavirin may not be uncommon, they are rarely serious enough to cause treatment interruption. More emphasis should be on supporting persons looking after LF cases adopt measures that minimize the risks of exposure.