Vaccination against cholera in crisis: Coverage and cost efficiency in Sudan (2023-2024)

Cholera remains a persistent public health challenge, particularly in resource-limited and conflict-affected settings where inadequate water, sanitation, and hygiene infrastructure exacerbate disease transmission. Sudan has experienced recurrent cholera outbreaks, with two major waves occurring between April 2023 and November 2024, affecting 63,112 individuals and resulting in 1377 fatalities. Given the ongoing armed conflict and humanitarian crisis, traditional cholera prevention measures are often insufficient, necessitating the rapid deployment of Oral Cholera Vaccine (OCV) as a key outbreak response strategy.

This study evaluates the administrative coverage, operational performance, and economic efficiency of Sudan's OCV campaigns during this period. A cross-sectional analysis was conducted on Sudan's nationwide OCV campaigns from November 2023 to November 2024. The study assessed vaccination strategies, cold chain resilience, social mobilization efforts, and operational costs per dose.

A total of 8,584,190 doses were administered to a target population of 8,654,546, achieving an administrative coverage rate of 99%. Coverage varied across implementation sites. The campaign was conducted under extreme conflict conditions, requiring innovative strategies such as house-to-house vaccination, mobile teams, and integration with novel Oral Polio Vaccine (nOPV) campaigns. Vaccine wastage was minimal (<0.0001 %), and the average operational cost per dose was $0.65. Despite logistical challenges, Sudan reduced the lead time from outbreak confirmation to vaccine request submission to just three days, though vaccine arrival delays of 2-4 weeks remained a bottleneck.

Sudan's experience demonstrates the feasibility and cost-effectiveness of OCV campaigns in conflict-affected and resource-limited settings. The high coverage rate, efficient vaccine utilization, and successful adaptation of vaccination strategies highlight the resilience of Sudan's health system in responding to outbreaks amid ongoing conflict and provide critical insights for future cholera control efforts in fragile settings, using partnerships, agile vaccine deployment mechanisms, and innovative implementation approaches.