COMPARISON OF ENZYME-IMMUNOASSAY, PCR, AND TYPE-SPECIFIC CDNA PROBE TECHNIQUES FOR IDENTIFICATION OF GROUP-A ROTAVIRUS GENE 4 TYPES (P-TYPE)

This study was designed to evaluate three techniques most commonly use d to identify the VP4 (P) types of human group A fecal rotaviruses, Th e techniques included PCR with nested primers and hybridization with P CR-generated probes (to determine the P genotypes). The results obtain ed by these genetic techniques were evaluated against those obtained b y an enzyme immunoassay (EIA) incorporating neutralizing monoclonal an tibodies (N-MAbs) reacting with three major human P serotypes (serotyp es pes PIA, PIE, and P2A). The P types of the rotaviruses present in 1 02 fecal specimens were determined under code by each of the three ass ays, The specificity of each assay was evaluated against a ''gold stan dard'' putative P type (P serotype and genotype) deduced from knowledg e of the VP7 (G) type and the origin of the fecal specimen. Overall co mparison of the results showed respective sensitivities and specificit ies of 92 and 92% for reverse transcription-PCR, 80 and 99% for hybrid ization, and 73 and 91% for EIA with N-MAbs. The hybridization assay r etained high sensitivity with specimens stored for greater than or equ al to 10 years, Hybridization assays with nonradioactive probes are re latively inexpensive and are suited for use in developing countries. I n summary, both genetic assays showed high sensitivities and specifici ties in assigning a P type to human fecal rotavirus strains. Further e valuation of the EIA with N-MAbs is required, together with incorporat ion of new N-MAbs for the detection of the additional P types detected in developing countries.