Simian foamy virus infections in a baboon breeding colony

The prevalence, transmission, and Variation of simian foamy viruses (SFVs) in baboons was investigated. Over 95% of adult baboons in the breeding colo ny as well as recently imported adult animals had high liters of anti-SFV s erum IgG. Maternal antibody was detectable in infants' serum up to 6 months of age. Approximately 30% of infants in breeding harems experienced SFV in fections by 1 year of age. Shedding of SFV in oral secretions was common, w ith 13% of samples from normal adult animals and 35% from immunosuppressed animals containing infectious SFV. SFV was isolated from three baboon subsp ecies (olive, yellow, and chacma baboons) and sequences from both the pol a nd the LTR regions of the provirus were amplified by PCR and sequenced. Phy logenetic analysis indicated that all baboon isolates formed a single linea ge distinct from SFVs of other African monkey species. Within the baboon SF V lineage, two distinct clades were apparent, which consisted of isolates f rom yellow and olive baboons and isolates from chacma baboons. Competition ELISAs indicated that, while SFV isolates of these two groups were very clo sely related, antigenic differences do exist between them. SFV isolates fro m a drill and a mandrill were distinct from baboon SFV isolates, both genet ically and antigenically. (C) 2000 Academic Press.