Epidemiological investigation of a cholera outbreak in Nepal–India border communities: Public health implications

•Cholera cases confirmed as Vibrio cholerae O1 Ogawa, all resistant to cotrimoxazole, accounted for 39% of the total.•In cholera-affected areas, 59% of household water samples were contaminated with fecal coliforms.•Antimicrobial resistance may worsen future cholera outbreaks, leading to drug-resistant strains.•Strengthening cross-border disease surveillance is critical for effective cholera outbreak control.•Urgent international collaboration is needed to meet the goal of ending cholera by 2030. On October 4, 2021, a cholera outbreak was reported in Kapilvastu District, one of Nepal's 26 districts bordering India. This study examined the outbreak's characteristics, response efforts, and the challenges faced. A descriptive cross-sectional design was applied for the outbreak investigation. Data were gathered through a review of cases registered in three local health facilities and community-based active case searching. A descriptive analysis was performed on the collected data. Between October 4 and December 2, 2021, 1570 cases were reported across 10 municipalities in Kapilvastu, with 88.6% of cases occurring in communities bordering India. Most affected were female patients (55%) and children aged 5-14 years (32%). A total of 39% cases were confirmed to have the Vibrio cholerae O1 Ogawa serotype, which showed resistance to cotrimoxazole. Additionally, 453 cases of acute watery diarrhea were identified in the community, with 23% showing signs of dehydration. Of 29 water samples, 17 (59%) were contaminated with fecal coliform. Communities along the Nepal–India border are highly vulnerable to cholera outbreaks, highlighting the urgent need for improved water, sanitation, and hygiene practices. A coordinated approach to cholera surveillance and preparedness is crucial to prevent future outbreaks.