From Outbreak to Control: A Rapid, Reactive OCV Campaign in Madhesh Province, Nepal

On 22 August 2025, a cholera outbreak was detected in Birgunj, Parsa District, and rapidly spread to neighboring Bara. Within days, more than 1 700 cases were reported, underscoring how rapidly the disease can spread in densely populated communities.

In response, Nepal launched a reactive Oral Cholera Vaccine (OCV) campaign, targeting all individuals aged one year and above across Parsa and six high-risk municipalities in Bara. With support from the International Coordinating Group (ICG) on Vaccine Provision, the campaign was rolled out and completed within just two weeks—a significant operational achievement—despite taking place between the major festivals of Dashain and Tihar. 

Caption: A student receives the oral cholera vaccine during the 2025 campaign.  

Led by the Family Welfare Division, with technical support from WHO and other partners, the response involved intensive planning and orientation across all three levels of government. WHO supported microplanning, logistics, risk communication and the establishment of monitoring systems. WHO’s independent monitors were mobilized to support advocacy and rapid convenience monitoring, strengthening accountability and enabling real-time feedback. 

Engagement with professional bodies, elected representatives, media, religious leaders, and ward‑level officials played a critical role in building trust and community acceptance. Initial vaccine hesitancy—driven by misinformation, fear of side effects, and low perceived risk—was addressed through targeted risk communication and endorsements from trusted local figures.

Caption: A WHO staff (Dr Rahul Pradhan, NPO, WHO-IVD) interacts with students at a vaccination site.

Mamta Chaudari, a health worker, said she used her experience with cholera to counsel others on prevention and the importance of vaccination. “I counsel others and encourage them to get the cholera vaccine and practice safe hygiene, so they don’t have to suffer like I did.”

To maximize reach, a combination of fixed sites, outreach services, and door-to-door strategies was deployed, ensuring access even in hard-to-reach areas. Within just two weeks, the campaign reached over 912 000 people, achieving 90% coverage. 

Caption: Ms. Mamta Chaudari, a health worker, says she used her experience with cholera to counsel others on the importance of OCV.

“The most effective intervention at the time of the outbreak was to launch a mass vaccination campaign, and I think it’s amazing just how quickly the government was able to manage the vaccines and roll out the campaign,” said Jaya Mod Thakur, Immunization Officer at Parsa Health Office. 

Caption: Beneficiaries show their vaccination cards after receiving OCV during the 2025 campaign

This rapid, large-scale effort contributed significantly to controlling the outbreak and reducing the risk of further transmission in high-burden areas. Strong community engagement, combined with door-to-door delivery and multi-stakeholder collaboration, improved access, acceptance, and trust across all age groups in the affected municipalities.

Caption: Dr Abhiyan Gautam, Chief of Child Health and Immunization Service Section, Family Welfare Division, during an orientation session prior to the OCV campaign rollout.

By reaching more than 900 000 people within a two‑week period, the campaign demonstrated that vaccines can be delivered rapidly and at scale, even in complex, high‑risk settings. Expanding eligibility to everyone above one year of age widened the protection window and ensured that no group was left behind, reinforcing the principle that vaccines provide timely protection for every generation while strengthening preparedness for future outbreaks.

Caption: Women line up to receive the oral cholera vaccine during the campaign in Chainpur.