Application of the fluorescent antibodies method for rapid diagnosis caused of diseases by pox viruses

The results of application of the fluorescent antibodies method (MFA) with the diagnostic purpose of detecting pox antigen in specimens from smallpox patients are presented. The method was found highly effective for the examination of material taken directly from the patients (smears) in the early stages of disease (maculo-papular and vesicular). The results of examination of smears from pustular fluid and scabs were not reliable in 44% of cases due to the presence of nonspecific fluorescence of tissue fragments and leukocytes. The technique of preliminary accumulation of the virus in a sensitive cell culture made the MFA suitable for the examination of material taken at any stage of disease. Results of the assessment of sensitivity of MFA in comparison with other methods of rapid diagnosis of smallpox are presented.