Silver staining of DNA restriction fragments for the rapid identification of adenovirus isolates: application during nosocomial outbreaks.

The ultrasensitive photochemical silver stain for nucleic acids, described by Beidler et al. (1982), has been applied to the detection of adenovirus restriction fragments as a relatively rapid technique for the identification of virus isolates. In this study, restriction enzyme cleavage analysis was used to characterize adenovirus isolates from what appeared to be two nosocomial outbreaks. The first outbreak was thus shown to include two clusters of patients, and involved two serotypes Ad7c and Ad40. The second outbreak was unrelated and involved Ad35. Although restriction analysis does not replace serum neutralization as a routine method for typing adenoviruses, it is a much more rapid means of discriminating between different patient isolates, providing a current rather than retrospective analysis of a nosocomial outbreak. During the first outbreak, restriction analysis identified two distinct adenovirus serotypes from one patient--Ad7c from a nasopharyngeal aspirate and Ad41 from a stool specimen. Restriction analysis is also valuable for the sub-typing of virus isolates. In this study, the Ad40 and Ad41 isolates were shown to be variants of the respective prototype strains.