Rift Valley fever

Rift Valley fever (RVF) is a zoonotic viral disease caused by Rift Valley fever virus (RVFV) ^[1]. The virus is an arthropod-borne virus and is reported to infect domestic and wild ruminants, including cattle, sheep, goats, camels, and buffaloes, as well as humans ^[1]. Source-backed detail on taxonomic lineage beyond its arboviral classification is not yet available in the provided material ^[1].

In humans, Rift Valley fever may cause moderate to severe illness, and the available abstracts describe a spectrum that includes febrile illness, ocular disease, hemorrhagic fever, and encephalitis ^[2]. The source material does not provide a standardized description of symptom timing, duration, or progression, so those details are not yet available from the evidence supplied ^[2]. In livestock, RVF is described as a severe veterinary disease ^[2].

RVFV was first isolated and characterized in the Rift Valley of Kenya in 1931 ^[1]. The disease is reported as endemic throughout sub-Saharan Africa, including Comoros and Madagascar, and also in the Arabian Peninsula, specifically Saudi Arabia and Yemen, as well as Mayotte ^[1]. The supplied literature emphasizes a complex ecological cycle involving mosquitoes, livestock, people, and the environment, and notes a significant risk of emergence into new locations ^[2]. Source-backed detail on current case counts or routine surveillance burden is not yet available ^[2].

RVFV is primarily spread through the bites of infected mosquitoes or exposure to infected blood ^[1]. Another source states that transmission to humans can occur from mosquitoes or farm animals, and that person-to-person transmission is generally not observed ^[2]. No further exposure-specific transmission details are supported by the provided sources ^[1][2].

The provided sources identify domestic and wild ruminants, including cattle, sheep, goats, camels, and buffaloes, as affected animal hosts ^[1]. Human exposure risk is linked to contact with infected mosquitoes and infected blood, including exposure associated with farm animals ^[1][2]. More specific occupational or demographic risk groups are not stated in the source material and are therefore not yet available from the evidence supplied ^[1][2].

The provided sources do not specify a formal prevention schedule or intervention package, so source-backed detail on vaccines, chemoprophylaxis, or other specific preventive measures is not yet available. The evidence does indicate that exposure control should be framed around mosquito-bite avoidance and avoiding contact with infected blood or animal sources, because these are the documented transmission pathways ^[1][2]. Preventive interpretation should also consider the virus’s livestock–mosquito–environment ecology ^[2].

In surveillance settings, Rift Valley fever should be interpreted as a zoonotic arboviral infection with both human and animal health implications ^[1][2]. The available evidence supports attention to febrile illness, ocular disease, hemorrhagic fever, and encephalitis in humans, alongside livestock disease and mosquito-associated exposure contexts ^[2]. Because the disease may emerge in new regions and is linked to animal and environmental interfaces, monitoring should integrate human, veterinary, and vector information where available ^[2].

1. 1 Kimble JB et al. Rift Valley Fever. Vet Clin North Am Food Anim Pract. 2024 Jul. PMID: 38453549. doi: 10.1016/j.cvfa.2024.01.004. PubMed: https://pubmed.ncbi.nlm.nih.gov/38453549/
2. 2 Hartman A et al. Rift Valley Fever. Clin Lab Med. 2017 Jun. PMID: 28457351. doi: 10.1016/j.cll.2017.01.004. PubMed: https://pubmed.ncbi.nlm.nih.gov/28457351/
3. 3 Chala B et al. Emerging and Re-emerging Vector-Borne Infectious Diseases and the Challenges for Control: A Review. Front Public Health. 2021. PMID: 34676194. doi: 10.3389/fpubh.2021.715759. PubMed: https://pubmed.ncbi.nlm.nih.gov/34676194/
4. 4 Pathogenesis of Viral Hemorrhagic Fevers: Rift Valley Fever and Lassa Fever Contrasted. Clinical Infectious Diseases. 1989. doi: 10.1093/clinids/11.supplement_4.s743. DOI: https://doi.org/10.1093/clinids/11.supplement_4.s743
5. 5 Bunyaviral Fevers: Rift Valley Fever and Crimean-Congo Hemorrhagic Fever. Tropical Infectious Diseases. 2006. doi: 10.1016/b978-0-443-06668-9.50072-7. DOI: https://doi.org/10.1016/b978-0-443-06668-9.50072-7
6. 6 Rift Valley fever. Nature. 1978. doi: 10.1038/271308a0. DOI: https://doi.org/10.1038/271308a0

ICD-10

A92.4

ICD-11

1D47

Total cases

0

Peak month

2005-01

Coverage

1 reporting countries · 2005-01-01 → 2026-06-01