In response to a Yellow Fever outbreak in December 2023, the Ministry of Health, supported by the World Health Organization (WHO), UNICEF and other partners, conducted a yellow fever vaccination campaign in Western Equatoria State. The campaign targeted Yambio, Nzara, Ibba, Ezzo, and Tambura Counties, reaching 465 798 persons with the lifesaving vaccine.

The outbreak, confirmed on 24 December 2023, marked the region's second major outbreak in over three years, following a previous episode in the neighboring county of Kajo Keji in 2020. The campaign aimed to vaccinate approximately 608 268 individuals aged nine months to 65 years. Despite logistical challenges and the complexities of operating in a conflict-affected area, the initiative achieved a 77% coverage rate, highlighting the difficulties in reaching all targeted individuals.