The World Health Organisation has issued a warning over a suspected outbreak of the deadly Marburg Virus. The virus is believed to have been found in the Kagera region of the United Republic of Tanzania. On January 10, WHO received reliable reports from sources in Tanzania regarding suspected cases of Marburg Virus Disease (MVD).
Six people were reported to have been affected, five of whom had died. The cases presented with similar symptoms of headache, high fever, back pain, diarrhoea, haematemesis (vomiting with blood), malaise (body weakness) and, at a later stage of disease, external haemorrhage (bleeding from orifices).
By January 11, nine suspected cases were reported including eight deaths – a fatality ratio of 89% – in the Biharamulo and Muleba districts. Samples from two patients have been collected and tested by the National Public Health Laboratory. Contacts, including healthcare workers, are reported to have been identified and under follow-up in both districts.
The Bukoba district in Kagera region experienced its first MVD outbreak in March 2023, and animal reservoirs of the virus, such as fruit bats, remain endemic to the area. The outbreak in March 2023 lasted for nearly two months with nine cases including six deaths.
National rapid response teams have been deployed to support outbreak investigation and response; surveillance activities have been intensified with contact tracing ongoing; laboratory samples from recent cases have been sent for confirmation at the National Public Health Laboratory. A mobile laboratory is located in Kagera region and treatment units have reportedly been established.
The risk of this suspected MVD outbreak is assessed as high at the national level due to several concerning factors. Healthcare workers are included among the suspected cases affected. The source of the outbreak is currently unknown.
The reporting of suspected MVD cases from two districts suggests it is spreading.
The regional risk is considered high due to Kagera region’s strategic location as a transit hub, with significant cross-border movement of the population to Rwanda, Uganda, Burundi and the Democratic Republic of the Congo. Reportedly, some of the suspected cases are in districts near international borders, highlighting the potential for spread into neighbouring countries. It cannot be excluded that a person exposed to the virus may be travelling.
There is no confirmed international spread at this stage, although there are concerns about potential risks. Kagera region is well-connected through transportation networks, and has an airport that connects to Dar es Salaam for onward travel outside Tanzania by air.
Human-to-human transmission of Marburg virus is primarily associated with direct contact with the blood and/or other bodily fluids of infected people.