Research

Seroprevalence of simian immunodeficiency virus in wild and captive born Sykes' monkeys (Cercopithecus mitis) in Kenya

Brett R Ellis¹ , Elephas Munene² , Debra Elliott³ , James Robinson³ , Moses G Otsyula² and Scott F Michael⁴

¹  Department of Tropical Medicine, Tulane University, New Orleans, LA 70112, USA

²  Institute of Primate Research, P.O Box 24481, Karen, Nairobi, Kenya

³  Division of Pediatric Infectious Diseases, Tulane University, New Orleans, LA 70112, USA

⁴  Biotechnology Program, Florida Gulf Coast University, Fort Myers, FL 33965, USA

author email corresponding author email

Retrovirology 2004, 1:34doi:10.1186/1742-4690-1-34

Published:	28 October 2004

Abstract

Background

The Sykes' monkey and related forms (Cercopithecus mitis) make up an abundant, widespread and morphologically diverse species complex in eastern Africa that naturally harbors a distinct simian immunodeficiency virus (SIVsyk). We carried out a retrospective serological survey of SIV infection from both wild and captive Sykes' monkeys from Kenya. We compared two commercially available, cross-reactive ELISA tests using HIV antigens with a novel SIVsyk antigen-specific Western blot assay and analyzed the data by origin, subspecies, age and sex.

Results

The SIVsyk antigen-specific Western blot assay detected more serum samples as positive than either of the cross-reactive ELISA assays. Using this assay, we found that seroprevalence is higher than previously reported, but extremely variable in wild populations (from 0.0 to 90.9%). Females were infected more often than males in both wild and captive populations. Seropositive infants were common. However, no seropositive juveniles were identified.

Conclusion

We have developed a specific and sensitive Western blot assay for anti-SIVsyk antibody detection. Sykes' monkeys are commonly infected with SIVsyk, but with extremely variable prevalence in the wild. Higher infection prevalence in females suggests predominantly sexual transmission. High infection prevalence in infants, but none in juveniles, suggests maternal antibodies, but little or no vertical transmission.