Emergency response unit – Rift Valley fever (RVF)

Status: in progress - level 1

Last updated on 24 November 2025

Rift Valley fever : main points of the situation

Since the outbreak was declared on 25 September, Senegal and Mauritania have reported 2,443 cases (321 confirmed cases; 2,123 suspected cases), including 37 deaths, and 1 case and 1 death in Uganda (1).
Senegal’s Minister of Health has announced a vaccination campaign for livestock, particularly small ruminants, and an awareness campaign calling on people to avoid contact with sick or dead animals and to go to the nearest health centre if they develop a fever.
The ANRS MIE activated a Level 1 Emergency Unit on 16 October 2025.

Rift Valley fever (RVF) is a viral zoonosis

RVF mainly affects ruminants (sheep, cattle, goats), with transmission to humans mainly through direct contact with the blood, fluids or tissues of infected animals (slaughter, cutting, plucking, ingestion of undercooked meat or raw milk).

Transmission by mosquito bites (Aedes, Culex, including C. pipiens and A. albopictus) also contributes to viral circulation (2,3). No human-to-human transmission has yet been documented (4)

Actions taken by ANRS MIE

As part of Level 1 of the Emergence Unit, the agency has undertaken several actions:

Monthly review of scientific literature and news

The ANRS MIE compiles and publishes online a monthly review of scientific literature and news.

The scientific review, which is available for download, includes:

a summary of the epidemiological situation;
recent scientific articles published in peer-reviewed scientific journals;
recent articles and press releases;
a brief overview of epidemiology, virology, clinical practice, treatment and prevention;
an update on current research into treatments and vaccines, with an overview of ongoing clinical trials;
official recommendations from health agencies.

Organisation of a research meeting

On 7 November 2025, ANRS MIE organised a research meeting on Rift Valley fever, in conjunction with the Arbo-France network and ANRS MIE’s coordinated action on viral haemorrhagic fevers.

On the agenda:

Introduction and objectives of the meeting (5 min) – Éric D’Ortenzio & Coumba Toure Kane
Epidemiological overview (10 min)
- Senegal – Current epidemiological situation, haemorrhagic forms observed, surveillance systems and vaccination strategy (5 mins), Dr Boly Diop, Head of the Epidemiological Surveillance and Vaccination Response Division at the Ministry of Health and Social Action.
- Mauritania – Patient follow-up, surveillance organisation and national response to the epidemic (5 min), Mohamed Lamine Diakité, Epidemiological Surveillance Department/DMPLM
State of research on RVF (30 min)
- Modelling the transmission dynamics of the RVF virus (10 min), Raphaëlle Métras, researcher at INSERM (CRCN), Pierre Louis Institute of Epidemiology and Public Health (IPLESP, UMRS 1136)
- Veterinary perspectives on Rift Valley fever surveillance and prevention (10 min), Éric Cardinale, Scientific Director of Animal Health, ANSES
- Reflections on the integration of social sciences into surveillance and response strategies (10 min), Albert Gauthier Ndione, Socio-anthropologist, Cheikh Anta Diop University, Senegal
Discussion

The minutes and some of the presentations are available for download below:

Epidemiological situation of Rift Valley fever in Africa

As of 27 October, Senegal had reported 2,266 cases (277 confirmed and 1,989 suspected) and 22 deaths, mainly in the Saint-Louis region (87% of confirmed cases). The disease is present in eight of its regions.

In Mauritania, the Ministry of Health reported 176 cases (42 confirmed and 134 suspected) and 14 deaths in 11 of the 15 regions (4).

A single case has just been reported in Uganda (5) for the very first time. This death does not appear to be linked to the current epidemic in West Africa.