SHEDDING AND TRANSMISSION OF BABOON HERPESVIRUS-PAPIO-2 (HVP2) IN A BREEDING COLONY

Baboons in a captive breeding colony were monitored twice a year, and new additions were screened on arrival for shedding of Herpesvirus pap io 2 (HVP2) and serologic reactivity to the agent, For 128 individual animals tested over a period of 1.5 years, shedding of infective virus was detected in 13 of 342 swab specimens (3.8%), each of these incide nts representing shedding by a different animal, Among long-term colon y animals, infective virus was recovered on only two occasions (5 of 2 36 swab specimens from five individuals), In all but one instance, ani mals shedding virus were infants, not adults, and all animals were she dding virus in the oral cavity. One of these five instances was an iso lated case, but four (three infants and one adult) were clustered with in a single breeding group, Molecular analyses of the HVP2 isolates fr om this cluster indicated that they likely arose from a single common source, probably the mother of one of the infants, None of 31 wild-cau ght baboons added to the colony during this period were found to be sh edding infective virus, despite 93.5% of them being seropositive for H VP2, In contrast, 6 of 18 adult baboons (all seropositive) transferred into the colony from another breeding colony were found to be sheddin g HVP2 either orally (3 of 6) or genitally (3 of 6), In addition, 2 of 8 juvenile baboons in this shipment were found to be shedding virus i n the oropharynx, Overall, 10 of 13 instances of HVP2 isolation were f rom the oropharynx rather than the genital tract, and 6 of 13 baboons shedding virus were infants or juveniles rather than adults, These res ults suggest that, although venereal transmission of HVP2 occurs among adult animals, oral infection of young, sexually immature baboons is not uncommon.