South Sudan Faces Growing Ebola Risk as Outbreak Spreads in Eastern DRC

South Sudan faces a growing risk of Ebola transmission from neighboring Democratic Republic of Congo as the outbreak expands toward border areas, according to a rapid analysis by Mercy Corps.

The report, released in August 2026, says the outbreak in eastern DRC has moved closer to South Sudan, with confirmed cases reported in Haut-Uélé province and other health zones near the two countries’ borders.

As of Aug. 11, the outbreak had recorded 4,381 confirmed cases and 2,011 confirmed deaths, according to the analysis. Transmission continues to increase, with no clear indication that the outbreak has reached a plateau.

Mercy Corps said South Sudan is considered at high risk of Ebola importation because of extensive cross-border movement, weak surveillance systems and limited public health capacity.

The report identified four major travel corridors through which Ebola could reach South Sudan. It said health zones in Haut-Uélé, including Wamba, Isiro, Rungu, Pawa and Boma-Mangbetu, as well as northern Ituri areas including Aru, Ariwara, Adja and Mahagi, have reported confirmed cases since early July.

Isiro and Wamba, which anchor important routes toward South Sudan, have developed into clusters, raising concerns that continued transmission could spread along established travel and trade routes.

Population movement remains the main driver of the risk, the report said. Western and Central Equatoria states have regular cross-border movement with northeastern DRC through both formal and informal routes, many of which have little or no health screening.

Conflict-related displacement, economic pressures and the movement of refugees, returnees, traders and other travelers further complicate surveillance and contact tracing.

Mercy Corps warned that South Sudan has a limited window to strengthen preparedness before the virus reaches its borders. Gaps remain in surveillance, community engagement, staffing, logistics and funding.

The analysis also found that Ebola preparedness has received less attention from many humanitarian organizations than other emergencies, including conflict, displacement, food insecurity, cholera and flooding.

It said dedicated funding for Ebola preparedness remains limited, with preparedness activities often being implemented through existing health programs rather than through dedicated Ebola funding.

South Sudan’s porous borders with DRC and Uganda present another major challenge. Although screening is conducted at major entry points such as Nimule, Kaya, Lasu and Juba International Airport, travelers also use unofficial crossings where surveillance is limited or absent.

The report said local traders, farmers, students, patients, internally displaced people, refugees and returnees frequently cross the border through informal routes, making it difficult to rely solely on screening at official entry points.

Community awareness is also uneven in some border areas. Stakeholders told Mercy Corps that fear, uncertainty and limited knowledge about Ebola remain common, making sustained community engagement critical for early detection and reporting.

The report cited an estimated 70% probability of Ebola spreading into South Sudan from the current outbreak, while noting that the greatest concern is delayed detection after an imported case arrives.

The Government of South Sudan has activated preparedness mechanisms and strengthened surveillance in border counties, but many activities continue to depend on external partners for technical expertise, logistics, training and operational support.

Mercy Corps recommended increased investment in surveillance, risk communication, frontline health worker preparedness, rapid response teams and cross-border coordination, particularly in high-risk areas of Central and Western Equatoria.

The organization said early investment in preparedness would be significantly less costly than responding to an outbreak after Ebola enters South Sudan.

The report concluded that the Ebola threat could increase suddenly rather than gradually. It noted that the outbreak has moved in sharp geographical jumps, including a significant advance in mid-July toward areas near the Uganda and South Sudan borders.

Mercy Corps warned that population mobility, porous borders and weaknesses in the health system could create conditions for rapid cross-border transmission. It called for increased attention from the government, humanitarian organizations and donors before an imported case occurs.