Country: Nigeria Sources: Health Cluster, World Health Organization Please refer to the attached file. This Situation Report provides an update on the cholera outbreak response in Borno State, Nigeria, covering the period from 1 to 20 May 2026. As of 20 May 2026, a cumulative 2,081 cholera cases and 23 associated deaths had been reported across five LGAs, with a case fatality rate (CFR) of 1.1%. The report notes the geographic expansion of the outbreak, including newly affected Monguno LGA, and summarizes ongoing surveillance, laboratory testing, case management, WASH, risk communication, and multisectoral coordination activities.