Review article

Rift Valley fever virus (Bunyaviridae: Phlebovirus): an update on pathogenesis, molecular epidemiology, vectors, diagnostics and prevention

¹ AFSSA site de Lyon, 31 avenue Tony Garnier, F-69364 Lyon Cedex 7, France
² V et A gro S up, Campus Vétérinaire de Lyon, 1 avenue Bourgelat, F-69280 Marcy L’Etoile, France
³ Institut Pasteur, Unité de Génétique Moléculaire des Bunyavirus, 25 rue du Dr Roux, 75724 Paris Cedex, France
⁴ Centers for Disease Control and Prevention (CDC), Special Pathogens Branch, 1600 Clifton Rd, Mailstop G-14 SB, Atlanta, GA 30333, USA
⁵ Special Pathogens Unit, National Institute for Communicable Diseases, National Health Laboratory Service, Private Bag X4, Sandrigham 2131, Republic of South Africa

^* Corresponding author: m.pepin@afssa.fr or m.pepin@vetagro–sup.fr

Received: 5 February 2010
Accepted: 21 May 2010

Abstract

Rift Valley fever (RVF) virus is an arbovirus in the Bunyaviridae family that, from phylogenetic analysis, appears to have first emerged in the mid-19th century and was only identified at the begininning of the 1930s in the Rift Valley region of Kenya. Despite being an arbovirus with a relatively simple but temporally and geographically stable genome, this zoonotic virus has already demonstrated a real capacity for emerging in new territories, as exemplified by the outbreaks in Egypt (1977), Western Africa (1988) and the Arabian Peninsula (2000), or for re-emerging after long periods of silence as observed very recently in Kenya and South Africa. The presence of competent vectors in countries previously free of RVF, the high viral titres in viraemic animals and the global changes in climate, travel and trade all contribute to make this virus a threat that must not be neglected as the consequences of RVF are dramatic, both for human and animal health. In this review, we present the latest advances in RVF virus research. In spite of this renewed interest, aspects of the epidemiology of RVF virus are still not fully understood and safe, effective vaccines are still not freely available for protecting humans and livestock against the dramatic consequences of this virus.