Emmanuel Mfitundinda, Daniel Wenani, Hannington Katumba, Gertrude Abbo, Janet Lubega Kobusinge, Charity Mutesi, Patrick Kwizera, Emmanuel Okiror Okello, Annet Mary Namusisi, Joanita Nalwanga, Bridget Ainembabazi, Olive Loryndah Namakula, Joyce Owens Kobusingye, Vianney John Kigongo, Deborah Aujo, Denise Aman Kyomugisha, Martha Dorcas Nalweyiso, Pauline Achom, Nasif Matovu, Michael Mutegeki, Winfred Nakaweesi, Sharon Namasambi, Maria Nakabuye, Justine Wobusobozi, Amina Namwabira, Anne Loy Alupo, Esther Nabatta, Winnie Agwang, Samuel Lugwana, Tracy Rutogire, Ritah Namusoosa, Wilfred Opeli, Robert Namisi Masaba, Martha Nakaye, Florence Nambaziira, Caroline Musubiika, Vivian Nakaweesa, Samuel Gidudu, Rebecca Akunzirwe, Jane Frances Zalwango, Mackline Ninsiima, Daniel Eurien, Aggrey Byaruhanga, Sunday Kithula Haggai, Bernard Lubwama, Godfrey Bwire, Moses Ebong, Dansan Atim, Patricia Eyu, Hildah Tendo Nansikombi, Irene Byakatonda Kyamwine, Job Morukileng, Richard Migisha, Benon Kwesiga, Paul Edward Okello, Lilian Bulage, Kami L Smith, Joseph Ojwang, Sam Wasike, Stephen Balinandi, Luke Nyakarahuka, Julius Julian Lutwama, Pontiano Kaleebu, Sandra Nabatanzi, Brittany Gianetti, Daniel Kadobera, Allan N Muruta, Mary A Boyd, Alex Riolexus Ario
The outbreak had a low CFR and a low Rt, possibly due to early detection and swift identification, quarantine, and close monitoring of contacts.
BACKGROUND: On January 30, 2025, the Ministry of Health, Uganda (MoH), announced an outbreak of Sudan ebolavirus disease (SVD). We describe the epidemiological characteristics and transmission dynamics of the SVD outbreak in Uganda during January-April, 2025.
METHODS: SVD cases were identified using MoH case definitions and were classified as confirmed if positive on RT-qPCR or probable if an SVD-related death was reported with epidemiological linkage but without laboratory confirmation. Cases were identified through contact tracing, community and health facility alerts, and active search. Data were collected using a standard SVD case investigation form, including demographics, exposures and outcome. The effective reproductive number (Rt) was estimated using the EpiEstim package in R.
RESULTS: Fourteen cases were identified between January 30 and April 25, 2025: 12 (86%) were confirmed and 2 (14%) were probable; and 5 (36%) were health workers. The mean (range) age was 27 (0-50) years. Four cases died, a case fatality rate (CFR) of 29% (4/14). Most exposures were household (9[64%]) followed by healthcare-associated exposures (3[21%]). The index case was a health worker who died of a febrile illness 11 days after symptom onset, and postmortem samples returned positive for SUDV on the same day. A total of 534 contacts were monitored; of these, 454 (85%) were quarantined. Ten cases were known contacts; no secondary transmission occurred among these cases. The estimated Rt (interquartile range) was 1.1 (0.83-1.35).
CONCLUSION: The outbreak had a low CFR and a low Rt, possibly due to early detection and swift identification, quarantine, and close monitoring of contacts.