Laboratory Diagnosis of Virus Infections

Virus Diagnosis Direct demonstration of the virus, its antigens or nucleic acid Virus Isolation: Chick embryo Cell culture (cell line) Animal inoculation Serology

Direct Demonstration of virus, antigens or nucleic acid Cytology (CPE: cell lysis, vacuolation, syncytia, changes in cell morphology, inclusion bodies) Electron microscope (number of virus particles) Genetic Probing using tagged probes specific for a unique target sequence in the viral genome Direct Immunofluorescence, ELISA, RIA, latex agglutination

Virus Isolation (cell line) Primary cell line Diploid cell line Continuous cell lines (HeLa)

Virus Isolation (cell line) Virus growth is detected in cell line by CPE, interference, hemadsorption, hemagglutination)

Serology Detection of antibodies to the virus Has limitations IgM, 4-fold or more increase in IgG or high fixed titre Neutralization, hemagglutination inhibition, ELISA, indirect fluorescent test, RIA, latex agglutination