Characterization of blood-borne transmission of simian foamy virus.
BACKGROUND
Simian foamy virus (SFV) is an endemic, nonhuman primate (NHP) retrovirus that is transmitted to individuals who work with or hunt NHPs. The cross-species transmission of simian retroviruses is believed to be the etiology of human immunodeficiency virus and human T-lymphotropic virus infections in humans. Although SFV is not pathogenic in the native host, the shared ancestry with other simian retroviruses has brought into question the potential for acquired pathogenicity after cross-species transmission. This study examines whether SFV also shares the traits of transmissibility through the blood supply.


METHODS
Within a controlled environment, blood from an SFV-infected monkey was transfused into an SFV-uninfected monkey. Evidence of infection, pathogenic effects, immune correlates, and viral shedding were followed for 6 months after transfusion.


RESULTS
Molecular evidence of SFV infection manifested 8 weeks after transfusion followed by seroconversion 1 week later. Quantitative analysis demonstrated that the highest level of detectable virus was concomitant with seroconversion followed by establishment of a viral "set-point." Analysis of circulating lymphocytes revealed changes early in infection. Potential routes of transmission of SFV and roles of site-specific immune response are suggested by the late appearance of SFV shedding in the saliva of the transfused animal.


CONCLUSIONS
The blood supply has historically provided a portal through which novel, occult viruses can become disseminated among humans. The demonstration of transmissibility of SFV through whole-blood transfusion, in an NHP model, contributes to the understanding of potential risks associated with blood donation by SFV-infected humans.
Brooks
James I
JI
National HIV & Retrovirology Laboratories, Center for Infectious Disease Prevention and Control, Public Health Agency of Canada, Ottawa, Ontario, Canada. James_Brooks@phac-aspc.gc.ca
Merks
Harriet W
HW
Fournier
Jocelyn
J
Boneva
Roumiana S
RS
Sandstrom
Paul A
PA
D000818:Animals; D001769:Blood / Q000821:virology*; D016516:CD4-CD8 Ratio; D003199:Computer Systems; D004279:DNA, Viral / Q000097:blood / Q000378:metabolism; D005434:Flow Cytometry; D008198:Lymph Nodes / Q000821:virology; D018655:Lymphocyte Count; D008252:Macaca fascicularis; D012192:Retroviridae Infections / Q000097:blood / Q000635:transmission* / Q000821:virology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012463:Saliva / Q000821:virology; D016092:Spumavirus / Q000302:isolation & purification*; D013997:Time Factors; D065227:Transfusion Reaction; D019562:Viral Load; D017201:Virus Shedding
D004279:DNA, Viral