African Swine Fever in Sub-Saharan African Countries
Abstract
African swine fever (ASF) is a dreadful hemorrhagic disease of domestic pig and European wild boars that causes up to 100% mortality in a naive population with a wide range of clinical symptoms and lesions depending upon the virulence of the virus strain involved and host factors. It is due to a unique double-stranded DNA virus, ASF virus (ASFV), an arbovirus harbored by soft ticks of the Ornithodoros spp. as vector and maintained in a sylvatic cycle between the soft ticks and the natural hosts, warthog, and bush pigs. However, there is also a domestic cycle for the persistence of the virus involving pig to pig transmission mainly observed in West and Central Africa where soft ticks do not exist and the disease is endemic. From Africa the disease had spread to West Europe, South America, and the Caribbean. The disease had been eradicated from these countries, except Sardinia in Italy. Nowadays the disease is reported in several countries of Eastern Europe including the Caucasus region and the Federation of Russia.
The control of ASF requires some prerequisites such as a laboratory able to diagnose quickly the disease and the veterinary services with adequate capacity to react. Furthermore, the control requires to prevent contact between domestic pigs and any sources of the virus and soft ticks where it exists. In addition, the effective cooperation of all stakeholders in a control and eradication plan is highly needed. Since free-ranging farm system with low biosecurity is common in Africa, approximately 80% of the domestic population, and that contributes to the maintenance of the virus, upgrading the farming system including an improved biosecurity level will effectively help to control the disease.
Keywords
African swine fever Virus Arbovirus Africa DNA Arthropod PigReferences
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