Introduction: syphilis rapid test results may be influenced by numerous environmental and genetic factors.

Methods: the proportion of false positive syphilis non-treponemal (NT) and treponemal (T) test results using immuno-chromatographic dual syphilis rapid test on serum from Cameroonian blacks (n=103) versus French blacks (n=104) or French caucasians (n=51), all HIV-negative and free of clinical syphilis, was examined.

Results: black individuals in Cameroon had a significantly higher frequency of false positive NT or T tests than black individuals in France. black individuals in France had a higher frequency of indeterminate NT tests as compared to caucasians in France.

Conclusion: both racial and environmental factors may affect immuno-chromatographic dual syphilis rapid testing.