On Mar. 21, 2023, the Ministry of Health of the United Republic of Tanzania declared an outbreak of Marburg virus disease in the country. As of Mar. 22, a total of eight cases, including five deaths (case fatality ratio [CFR]: 62.5%) had been reported from two villages in Bukoba district, Kagera region.

The first identified case reported travel history from Goziba Island in Lake Victoria in Tanzania and developed symptoms after returning to his village in Bukoba. The case died in the community. Four additional cases were identified from the same family as this index case. Further, two cases were reported among healthcare workers who treated them, one of whom died. No information is available on the eighth case; investigations are ongoing.

Reported symptoms of the patients were fever, diarrhoea, vomiting, bleeding from various sites, and kidney failure. Samples from both deceased and live cases were taken and confirmed for Marburg virus by the National Public Health Laboratory.

This is the first Marburg virus disease outbreak reported in the country. As response measures, Rapid Response Teams have been deployed to investigate and implement interventions in the affected areas, including contact tracing and risk communication activities.

WHO assesses the risk of spread as very high at the national level, high at the subregional level, and moderate at the regional level due to cross-border movements between Kagera region and bordering countries including Uganda in the north, Rwanda and Burundi in the west. The risk at the global level is assessed to be low.