For Surveillance in study CTCs  Inclusion Criteria:  All patients presenting at the time of the study to any selected Cholera Treatment Center/Cholera Treatment Unit (CTC/CTU), matching the case definition and giving his/her consent (or assent for children 8 to 17 years old) to participate in the study will be eligible.  Exclusion Criteria:  Patients who decline to participate will be excluded from the study.  Follow up of individuals with active cholera shedding:  Inclusion Criteria:  present to any selected CTC/CTU, match the case definition, participate to the clinical surveillance activity and test positive to RDT OR Be a household member of a person respecting inclusion criteria 1. AND for whom the head of the household has provided verbal consent to participate AND giving his/her consent (or assent for children 8 to 17 years old) to participate in the study will be eligible.  Exclusion Criteria:  - Individuals who decline to participate will be excluded from the study, as well as households for whom the head of the household (and his or her representative) decline the participation of his/her household.