Mapping the high burden areas of cholera in Nepal for potential use of oral cholera vaccine: An analysis of data from publications and routine surveillance systems

ABSTRACT

Objective: To assess the extent of existing published evidence on cholera and to characterize the epidemiologic data of cholera in Nepal. Methods: We conducted a literature scoping review by summarizing published literature reporting on cholera in Nepal from January 1946 to March 2019 in online databases: MEDLINE, Embase, Cochrane, and Global Health. Additionally, we reviewed national surveillance data on clinically diagnosed and laboratory confirmed cholera reported by the Ministry of Health and Population. Results: Most of the published studies were conducted predominantly in Kathmandu Valley during the rainy season; however, outbreaks have been reported in other parts of Nepal including Terai, Hilly and Mountain regions. Our literature review exhibited that all age groups were affected by cholera, but particularly children and young adults were at-risk age groups in Nepal. Vibrio cholerae serogroup O1, biotype El Tor, serotype Ogawa has been predominantly isolated with an emergence of resistant strains since 1996. Two mass vaccination campaigns using oral cholera vaccines were conducted: Rautahat district in 2014 and Banke district in 2017. Conclusions: Capacity building for a nation wide systematic cholera surveillance with rapid and reliable diagnosis is needed to better estimate the burden of cholera and identify geographically at-risk areas associated with the disease in Nepal. It is essential for developing an adequate policy on oral cholera vaccine introduction and effective water, sanitation and hygiene interventions.