| Abstrakt: |
Nairobi sheep disease (NSD), is a serious tick-borne viral disease of sheep and goats. The virus belongs to the genus Nairovirus within family Bunyaviridae. In Africa, the principal vector for NSDV is the brown ear tick (Rhipicephalus appendiculatus), in which the virus can survive up to 800 days. Transovarial and transstadial transmission occurs via this tick. Nairobi sheep disease is characterized by fatal hemorrhagic gastroenteritis, starting with high fever, depression, respiration problems, myocarditis and tubular nephritis, often pulmonary edema, and very high mortality rate, up to 30–90%. Affected animals may die within a few days, and pregnant females abort. Subclinical infections also occur, and recovered animals are immune. NSDV is shed in urine and feces; however, the disease is not transmitted via contact between animals. Indirect fluorescent antibody tests are recommended for detecting antibodies in the infected or recovered animals. For laboratory diagnosis immunodiffusion, hemagglutination, ELISA, complement fixation test and also RT-PCR may also be used. There is no commercial vaccine for NSD. However, in endemic areas experimental vaccines have been developed for use in naïve animals entering enzootic areas, or to protect animals when tick vectors expand their geographical range. Control depends primarily on dipping small ruminants to control the tick vector. [ABSTRACT FROM AUTHOR] |
