Research and analysis
Outbreaks under monitoring: week 47 (week ending 23 November 2025)
Updated 31 December 2025
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| Disease or pathogen | Marburg disease |
|---|---|
| Location | Ethiopia |
| Status | New incident |
| Reporting date | 12 to 23 November 2025 |
| Summary | On 14 November 2025, the World Health Organization (WHO) confirmed the country’s , following laboratory testing of samples from the cluster of . As of , 10 confirmed cases and 5 confirmed deaths have been reported. 57 persons are under laboratory investigation. that the Marburg virus detected in this outbreak is of the same strain as the virus reported in previous outbreaks in East African countries. The source of the infection has not yet been identified although initial investigations show the presence of (a reservoir of Marburg virus). National health authorities are measures including screening, testing, contact tracing and public sensitization to control the outbreak. The WHO and other partners are supporting Ethiopia’s health authorities through with expertise in responding to VHF outbreaks, as well as providing other medical supplies and equipment. On 23 November 2025, reported that the Kenyan Government has enhanced cross-border surveillance at airports and all other points of entry from Ethiopia. No known human Marburg cases have been reported in the UK. The risk of this outbreak to the UK public is currently considered very low. |
| Further information |
Marburg virus disease: origins, reservoirs, transmission and guidelines Viral haemorrhagic fever: ACDP algorithm and guidance on management of patients Marburg contact tracing (collection page) Ebola and Marburg: returning workers scheme NaTHNaC country information page: |
| Disease or pathogen | Rift Valley fever |
|---|---|
| Location | Mauritania and Senegal |
| Status | Situation update |
| Reporting date | 26 September to 23 November 2025 |
| Summary | On 26 September 2025, Senegal’s Ministry of Health and Public Hygiene of Rift Valley fever (RVF) in the Saint-Louis region. As of 22 November 2025, , including 31 deaths, have been reported. Most cases have been reported in Saint-Louis region (351 cases). This is an increase of 35 cases since the .  suggests that the current outbreak is directly linked to the previous detections in Senegal (Fatick in 2020 and Matam in 2022) and Mauritania (2020). Between 1 January and 21 November 2025, , have been reported across 14 regions of Mauritania. This is an increase of 6 confirmed cases and one death since the last report with data up to . The WHO currently assesses the in Mauritania and Senegal as high at the national levels, moderate at the regional level and low at the global level. No known human RVF cases have been reported in the UK. |
| Further information |
Viral haemorrhagic fevers: origins, reservoirs, transmission and guidelines NaTHNaC country information page: and |