ABSTRACT
An apparently new strain of bluetongue virus was first isolated in Kenya in 1965 and since, has been obtained on 7 further occasions from diseased sheep during clinical outbreaks of disease. It proved to be serologically different from the 16 bluetongue virus strains then held at this laboratory. The virus was modified by passage in embryonated hens eggs to produce a live virus strain suitable for inclusion in a polyvalent vaccine. Recent neutralisation tests, carried out with 24 guinea pig immune sera prepared at Pirbright against the currently known World serotypes, have confirmed the earlier results and show that it is different from any of the existing serotypes.
Subject(s)
Bluetongue virus/isolation & purification , Bluetongue/microbiology , Disease Outbreaks/veterinary , Animals , Antibodies, Viral/biosynthesis , Antibodies, Viral/blood , Bluetongue/epidemiology , Bluetongue virus/classification , Bluetongue virus/immunology , Fluorescent Antibody Technique , Immune Sera/immunology , Kenya/epidemiology , Neutralization Tests , Serotyping , Sheep , Vaccines, Attenuated/immunology , Viral Vaccines/immunologyABSTRACT
The laboratory methods available for the isolation and identification of Nairobi sheep disease virus have been compared. The results show that inoculation of tissue culture (BHK 21 C 13) with suspensions of infected organs or plasma followed by fluorescent antibody tests on coverslip preparations gave the quickest means of identification. This test did not depend on the production of a cytopathic effect. Primary isolation of the virus in infant mouse brain and identification either by fluorescent antibody methods or by complement fixation with antigen prepared from the mouse brain offers a slightly more sensitive isolation system and would be recommended where no tissue culture facility exists.
Subject(s)
Nairobi Sheep Disease/diagnosis , Animals , Arboviruses/growth & development , Arboviruses/immunology , Arboviruses/isolation & purification , Cells, Cultured , Complement Fixation Tests , Cytopathogenic Effect, Viral , Fluorescent Antibody Technique , Mice , Nairobi Sheep Disease/immunology , Nairobi Sheep Disease/microbiology , SheepABSTRACT
A virus was isolated from pock-like vesicular eruptions of camels in Northern Kenya. This virus was shown to be a pox virus with many characteristics of members of the Orthopox group. It appears to be identical with camelpox strains from Iran and has similar properties to certain East African variola strains.
