RAPID SCREENING FOR RESISTANCE TO GANCICLOVIR AND FOSCARNET OF PRIMARY ISOLATES OF HUMAN CYTOMEGALOVIRUS FROM CULTURE-POSITIVE BLOOD-SAMPLES

A rapid screening assay for the detection of resistance to ganciclovir and foscarnet of primary isolates of human cytomegalovirus from cultu re-positive blood samples was developed by using single doses of both drugs and an immediate-early antigen plaque reduction assay. Results o f the rapid assay with peripheral blood leukocytes as the viral inocul um were compared with those of a conventional assay with cell-free vir us from the relevant viral isolates. Both assays gave overlapping resu lts. The rapid assay offers the following major advantages: (i) it pro vides results within 4 to 6 days, (ii) it can be performed with periph eral blood leukocytes, and (iii) it reliably detects drug-resistant hu man cytomegalovirus strains.