Analysis of acquired human cytomegalovirus infections by polymerase chain reaction

We used the polymerase chain reaction and primers corresponding to three regions of the human cytomegalovirus (HCMV) genome to study HCMVs isolated from 16 children attending a single day-care center and the father of two children in the same center. When we analyzed isolates with primers for the pp65 and major immediate-early genes, we observed nearly uniform amplification yielding products of predicted sizes. By contrast, primers for the a sequence demonstrated variability among HCMV strains, supporting the use of these primers as an epidemiologic tool. Analysis of a-sequence products from two isolates demonstrated 50 to 70% nucleotide homology with the a sequence of HCMV Towne strain DNA. We observed 95% nucleotide homology for the two a-sequence products derived from the father-child pair. Analysis of day-care center isolates indicated that two children excreted two distinct HCMV strains during the study interval.