Cross-Border Dynamics Between Burundi and Tanzania in the Context of Viral Haemorrhagic Fever Outbreaks, 2025

This brief summarises key considerations regarding cross-border dynamics between the Republic of Burundi and the United Republic of Tanzania in the context of viral haemorrhagic fever (VHF) outbreaks in Tanzania and the Republic of Uganda.

On 13 January 2025, the World Health Organization reported a suspected outbreak of Marburg virus disease (MVD) in Kagera Region of north-west Tanzania.¹ On 20 January 2025, the government of Tanzania officially declared an outbreak.² As of 26 February 2025, there have been 10 deaths from two confirmed and eight probable cases in Kagera’s Biharamulo and Muleba Districts. This is the second MVD outbreak in Kagera Region. In 2023, there were eight confirmed cases and one probable case, with six deaths, in Bukoba District.^3,4 The origin of these outbreaks is yet to be confirmed.

On 30 January 2025, the government of Uganda declared a Sudan virus disease (SVD) outbreak in Kampala, the capital city. SVD is one of six known viruses within the genus Ebolavirus and one of four that capable of causing Ebola virus disease (EVD) in humans and other primates; it is the sole member of the species Sudan Ebolavirus. As of 5 March 2025, 14 cases have been confirmed, with four deaths.⁵ This is Uganda’s sixth Sudan virus disease outbreak. The previous outbreak, in 2022, resulted in 164 cases and 55 deaths.⁶

MVD and SVD are VHFs. Both can spread between humans through direct contact with infected bodily fluids or via contaminated surfaces and materials.^7,8 The potential for VHFs to spread into neighbouring countries makes understanding the dynamics at the Burundi-Tanzania border crucial.

This brief is based on a rapid review of existing published and grey literature, programmatic documents, previous ethnographic research in Tanzania and informal discussions with in-country colleagues.