RESUMEN
The experience with ELISA technique utilized at serological screening for orthopoxviruses in the Republic of Ivory Coast revealed factors reducing the sensitivity and the specificity of the test. It was found out that routine controls such as "positive" and "negative" sera as well as the accepted reading of the results by two-fold or higher increase of OD values as compared to the "negative" control may be not sufficient. A significantly enhanced sensitivity and specificity of reaction was achieved by simultaneous examination of each serum under study with a control antigen. Selection of optimal dilutions of each test component followed by spectrophotometric assay and calculation of results according to the given formula contributed to the same aim. As a result of these improvements the rate of antibody detection among revaccinees was enhanced from 19 to 78.8% and the titres of ELISA and virus neutralization tests correlated in 88% of cases.
Asunto(s)
Anticuerpos Antivirales/análisis , Poxviridae/inmunología , Antígenos Virales/inmunología , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Humanos , Pulmón/embriología , Viruela/inmunologíaRESUMEN
The Kuwait-5-67 strain of variola virus, although indistinguishable from variola virus in its other properties, behaved atypically in immuno-diffusion tests with antivaccinia serum. The precipitation line pattern produced was similar to that of cowpox virus but lacked one of the main precipitation bands given by all other strains of variola, alastrim and vaccinia viruses tested. Trypsin treatment of cowpox virus preparations revealed the missing precipitation line but did not do so with the Kuwait-5-67 strain. The antivaccinia serum absorbed by Kuwait-5-67 strain lost its ability to interact with this strain, but still gave precipitation lines with variola, vaccinia and cowpox viruses.