Human Participant Exposure Data Nearly two thirds of the study sample was male (62.2%), and the mean age of the study participants was 35 years (Table 2). Of participants who reported being exposed, 23 (28.0%) of 82 persons reported having been bitten by the temple’s macaques (Table 3). Five of the 23 reported being bitten more than once. Thirty-one (37.8%) of 82 reported having been scratched, including 9 persons who had been scratched more than once. In total, 37 (45.1%) of 82 reported having been either bitten or scratched. Of the 82 persons whose serum was tested for antibod- ies to SFV, 81 had negative results by Western blot. Serum from a 47-year-old farmer (BH66) was reactive to SFV gag proteins, p70/p74 (Figure 1). This man reported that he visited the monkey temple every day and had previously been bitten once and scratched on more than one occasion by macaques there. He reported that the bite and scratches, which occurred on his hands and toes, had bled and that he had washed the wounds and applied traditional medicines. He denied owning or coming into contact with a pet pri- mate. He also denied hunting primates or consuming pri- mate meat. Detection of SFV DNA in a Person from Bali To determine whether SFV was present in humans and macaques, we performed nested PCR amplification of SFV by using conserved primers designed to detect macaque SFV (29). SFV was detected in the macaques tested, as well as in the 1 human participant (BH66), whose serum contained antibodies to SFV. Blood samples from all 81 human participants that were seronegative for antibodies to SFV were also negative for SFV by PCR. The limits of sensitivity for nested PCR were 1–10 SFV DNA copies per 500 ng cellular DNA, as determined by dilution of a positive control plasmid. Quantitative PCR products of BH66, 5 of the Sangeh macaques (M. fascicularis), and 13 pet macaques (M. tonkeana, M. maura, and M. fascicularis) from Sulawesi, Indonesia, were cloned at least twice, sequenced, and com- pared with published sequences from a rhesus macaque (M. mulatta) (SFV-1mac, M55279), an African green mon- key (Cercopithecus aethiops) (SFV-3agm, M74895), and a chimpanzee (Pan troglodytes) (SFVcpz, U04327). As shown in Figure 2, SFV from BH66 was most closely related to an SFV sequence amplified from 1 of the macaques at the Sangeh Monkey Temple (BP6). To verify that the BH66 sample was of human origin and not a mis- labeled sample from an SFV-infected monkey, we ampli- fied a small fragment from the 12S ribosomal mitochondrial DNA from 2 healthy unexposed humans, BH66, several macaque species, and African green mon- keys; cloned the products; and derived DNA sequences. Primate-to-Human Retroviral Transmission in Asia Phylogenetic analysis (Figure 3) showed that the human DNA sample grouped with mitochondrial DNA sequences from humans, confirming that the BH66 sample was from a human. Lymphocytes from BH66 were not available for isolation of SFV directly. Discussion Human Infection with SFV at the Sangeh Monkey Forest This report documents the first case of SFV infection in a person with known exposure to free-ranging Asian primates. Antibodies to SFV were detected in serum, and SFV genomic segments were amplified from blood of the infected person. Because PCR is prone to contamination, which leads to false-positive results, PCR products were sequenced and compared to SFV from other macaque species. Phylogenetic analysis showed that SFV amplified from the infected human was most similar to SFV from M. fascicularis at the Sangeh monkey temple. Although ascertaining exactly how or when the person acquired his infection was not possible, he did report having been bit- ten once and scratched on a number of occasions by macaques at Sangeh. He denied other past contacts with primates. Because only 1 infected person was detected and our sample size was limited (82 persons), we cannot estimate the prevalence of SFV infection in this human sample. Previous research on naturally acquired SFV infection among bushmeat hunters in Central Africa found 10 who seroconverted in a population of 1,099 (1%), of which 3 also had positive results by PCR. Surveillance of larger Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 11, No. 7, July 2005 1031