Safety and Efficacy Oral Cholera Vaccine (OCV) in Hodeidah, Yemen

Background : A national Oral Cholera Vaccine (OCV) campaign was launched in Hodeidah, in response to the first outbreak in Hodeidah ,Yemen , May 2017. Objectives: Therefore. the study aimed to monitor the efficacy and determine the incidence of adverse events following immunization (AEFI) with OCV among the Hali District , Hodeidah peoples of Yemen. . Methodology: The study was designed in two phases, the phase I, a cross sectional survey was designed to monitor the safety (AEFI) of OCV where the study was carried out between 6th May 2018 and 30th August 2018. The study included 210 participants that were administrated the vaccine orally. The adverse events were reported after 24 – 72 hours from administration of vaccine. The phase II , a cohort study was designed after three months of OCV vaccination campaign that included 151 cholera patients in diarrhea treatment center (DTC) with reporting of vaccination status and vaccine efficacy (VE) of OCV was measured based on two methods , the first was rapid measurement method and the second was cohort study . Results: A total of 210, 40 % of males and 60 % of females, aged from 10 years to 60 years. 50 % of participants was children , 30 % of young and 20 % of elderly. The incidence of AEFI of OCV among participants was reported in 20 participants (9.52 %). While, non-serious were reported in 190 participants (90.48 %). The major adverse events were reported as the following: loss appetite (9.52%), vomiting (7.14%), diarrhea (4.29%), abdominal pain (1.92%), and fever (0%). On the other hand, the VE of OCV was 96.72% according to rapid estimation method and 98.65 % based on cohort study. Conclusion: Our findings concluded that OCV was highly safe and effective. Additionally, monitoring AEFIs during emergency cholera outbreak campaigns supports the favorable safety profile of OCV.