The Toscana Virus, belonging to the Phlebovirus genus of the Bunyaviridiae family, was isolated for the first time in
Italy in 1971. Since then, its presence in the mediterranean area has been established and its role as an etiological agent in human disease has been demonstrated. The disease caused by Toscana Virus is characterized by fever, strong headache and meningitis or meningoencephalitis. The infection is transmitted by hematophagous insects of the
Phlebotomus genus and is seasonal with a peak in the summer months, due to the life cycle of the vector.
Epidemiological data indicate that in areas where the Toscana Virus is endemic, many, perhaps the majority of cases of aseptic meningitis during the summer period are caused by this virus. Until now, the diagnosis of Toscana virus
infection has been mainly performed serologically. Specific antibodies of the IgM class are present during the acute
phase, while the presence of specific IgG antibodies in the absence of IgM indicates a previous infection. All the
serological methods adopted up to the present time require propagation of the virus in cell cultures; these methods can only be performed in specialized laboratories, while the infection canno tbe diagnosed in the majority of s erological laboratories. As it has been shown that the viral nucleoprotein is the chief target of the anti-Toscana virus antibodies, this has been expressed by recombinant DNA technology in E. coli and used to set up an immunoenzymatic kit for the detection of specific IgG and IgM, as an aid in the serological study of this virus.
Immunoenzymatic method for the qualitative determination of IgG and IgM-class antibodies to Toscana Virus (Sandly Fever Virus) in human serum. The test is based on the ELISA principle (Enzyme Linked ImmunoSorbent Assay) which uses the reaction between the antibodies present in the tested sample and the immobilized antigen bound to solid phases.The immunoglobulins bind to the antigen through incubation with diluted human serum. The result is expressed as an INDEX (ratio between the OD value of the sample and that of the Cut-off).