Detection of enterotropic mouse hepatitis virus fecal excretion by polymerase chain reaction

A reverse transcription and polymerase chain reaction method was developed and used to detect fecal excretion of enterotropic mouse hepatitis virus (MHV). A nested set of primers for polymerase chain reaction was located in the polymerase region of the MHV genome. The assay was used to follow the time course of enterotropic MHV excretion in mice after oronasal inoculation with the virus. The assay detected MHV genome excretion in all mice beginning on day 3 through day 21 after inoculation. No MHV genome was detected in inoculated mice on or after day 27 following inoculation. This time course of detection of excreted virus corresponded to the period of infectivity of this isolate in a previous study. These results indicate that reverse transcription and polymerase chain reaction are useful for enterotropic MHV detection in specimens that are easily and noninvasively obtained and are clinically relevant.