Primate-to-Human Retroviral Transmission in Asia saliva from primates are likely mechanisms of transmis- throughout the 6-hectare temple complex and into the sur- sion (25–27). rounding rice fields and farms. Most of the macaques’ Because SFV is not known to occur naturally in caloric intake is from daily provisions provided by temple humans, detecting serologic or molecular evidence, or workers and food given to them by visitors. both, of infection in a human, along with a history of close contact with primates, constitutes strong evidence for pri- Human Participant Sampling mate-to-human transmission, i.e., a marker for cross- In July 2000, as part of a larger study on the epidemiol- species transmission (28). Existing serologic and ogy of exposure to primateborne viruses at the Sangeh molecular techniques can sensitively and specifically monkey temple, 82 workers from Sangeh agreed to partic- detect human SFV infections (29). ipate in the present study (32). After informed consent was Primates and humans come into contact in a variety of obtained, a questionnaire designed to elicit demographic contexts in Asia, including owning primate pets, observing data as well as data describing the frequency and type of performance monkeys, participating in ecotourism activi- exposure to Sangeh’s macaques was administered in ties, hunting primates for bushmeat, and visiting monkey Bahasa Indonesia, the national language of Indonesia. Sub- temples (30,31). Monkey temples are religious sites that sequently, 10 mL of blood was withdrawn from each partic- have, over time, become associated with populations of ipants antecubital vein, 6 mL was centrifuged to extract free-ranging primates. Monkey temples are common serum, and the remainder was mixed with EDTA. Serum throughout southern and Southeast Asia, where primates specimens and whole blood were then stored at –20°C. play an important role in culture. Asia’s monkey temples annually bring millions of people, including hundreds of Macaque Sampling thousands of tourists, from around the world into close In July 2000, 38 macaques within the Sangeh monkey proximity with free-ranging primates (32–34). Worldwide, temple area and surrounding forest were darted oppor- monkey temples may account for more human-primate tunistically and sedated with 3 mg/kg of Telazol (tileta- contact than any other context. mine HCl/zolazepam HCl). Following universal In Bali, ≈45 temple sites contain substantial popula- precautions, researchers withdrew 10 mL of blood from tions of free-ranging macaques (33). Those who spend the each macaque’s femoral vein. The macaques were closely most time in or around monkey temples include workers monitored during anesthesia and recovery. Six milliliters who maintain the temples; nuns, monks, and others who of blood was placed in a serum separator tube and cen- live on or around temple grounds; merchants who sell a trifuged in the field to extract the serum. The remaining variety of goods to tourists; and farmers whose fields are blood was placed in a tube containing EDTA. Sera and raided by macaques. Worshippers and tourists may also whole blood were frozen and stored at –20°C. come into contact with temple macaques. These temples are thus an important context in which to investigate cross- Western Blot Analysis species transmission of infectious agents. Western blot immunoassays were performed with a few Serologic data on free-ranging Southeast Asian modifications (21). Briefly, human foreskin fibroblast cells macaques, though incomplete, suggest that SFV is enzoot- were infected with SFVbab1 (an isolate from a baboon) ic among these macaque populations and that correspon- and maintained until notable cytopathologic changes were ding rates of SFV infection are high (80%–100%) (L. observed (19). Culture supernatant fluid containing virus Jones-Engel, unpub. data). We hypothesized that humans was harvested, and SFV was purified through a 20% who come into contact with these macaques might similar- sucrose cushion, separated by sodium dodecyl sulfate– ly show evidence of infection with SFV and investigated polyacrylamide gel electrophoresis, and the antigens were this proposition among a group of persons who worked at blotted onto nitrocellulose sheets. The nitrocellulose paper or around the Sangeh monkey temple in Bali, Indonesia. was blocked with 3% bovine serum albumin and subse- quently incubated with serum at a dilution of 1:40. Viral Methods proteins were detected with the streptavidin-biotin system (Amersham Inc., Arlington Heights, IL, USA) by using diaminobenzidine as the substrate for color development. Study Site: Sangeh Monkey Temple The Sangeh monkey temple is in central Bali, The criterion used for a positive sample was antibody reac- Indonesia, ≈20 km north of Denpasar, Bali’s most popu- tivity to both p70 and p74 gag-related proteins (19). lous city. The 17th-century Hindu temple complex at Sangeh serves the surrounding community and is a popu- PCR Detection of SFV lar domestic and international tourist destination. DNA was purified from whole blood by using the Approximately 200 free-ranging M. fascicularis roam QIAamp DNA Blood Mini Kit (Qiagen, Inc., Valencia, Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 11, No. 7, July 2005 1029