Rift Valley fever: Real or perceived threat for Zambia?

doi:10.4102/ojvr.v79i2.466 http://www.ojvr.org Rift Valley fever: Real or perceived threat for Zambia? Authors: George Dautu1 Calvin Sindato2 Aaron S. Mweene1 Kenny L. Samui1 Polly Roy3 Robert Noad4 Janusz Paweska5 Phelix A.O. Majiwa6 Antony J. Musoke6 Affiliations: 1Department of Disease Control, University of Zambia, Zambia 2National Institute for Medical Research, Tabora, Tanzania 3London School of Hygiene and Tropical Medicine, London, United Kingdom 4Royal Veterinary College, Hatfield, United Kingdom 5National Institute for Communicable Diseases, Johannesburg, South Africa 6Onderstepoort Veterinary Institute, Onderstepoort, South Africa Correspondence to: George Dautu Email: [email protected] Postal address: PO Box 32379, Lusaka, Zambia How to cite this abstract: Dautu, G., Sindato, C., Mweene, A.S., Samui, K.L., Roy, P., Noad, R. et al., 2012, ‘Rift Valley fever: Real or perceived threat for Zambia?’, Onderstepoort Journal of Veterinary Research 79(2), Art. #466, 6 pages. http://dx.doi. org/10.4102/ojvr.v79i2.466 Note: Proceedings of the Conference of the Southern African Centre for Infectious Disease Surveillance ‘One Health’ held at the National Institute for Communicable Diseases, Johannesburg, July 2011. Rift Valley fever (RVF) in Zambia was first reported in 1974 during an epizootic of cattle and sheep that occurred in parts of Central, Southern and Copperbelt Provinces. In 1990, the disease was documented in nine districts of the provinces of Zambia. In the last two decades, there have been no reports of RVF. This long period without reported clinical disease raises questions as to whether RVF is a current or just a perceived threat. To address this question, World Organisation for Animal Health (OIE) disease occurrence data on RVF for the period 2005−2010 in the Southern Africa Development Community (SADC) was analysed. From the analysis, it was evident that most countries that share a common border with Zambia had reported at least one occurrence of the disease during the period under review. Due to the absence of natural physical barriers between Zambia and most of her neighbours, informal livestock trade and movements is a ubiquitous reality. Analysis of the rainfall patterns also showed that Zambia received rains sufficient to support a mosquito population large enough for high risk of RVF transmission. The evidence of disease occurrence in nearby countries coupled with animal movement, and environmental risk suggests that RVF is a serious threat to Zambia. In conclusion, the current occurrence of RVF in Zambia is unclear, but there are sufficient indications that the magnitude of the circulating infection is such that capacity building in disease surveillance and courses on recognition of the disease for field staff is recommended. Given the zoonotic potential of RVF, these measures are also a prerequisite for accurate assessment of the disease burden in humans.