Traditionally, laboratory-based serological tests such as Treponema pallidum particle agglutination (TPPA) and rapid plasma reagin (RPR) are widely used to diagnose treponemal infections (for example, syphilis and yaws). These tests cannot distinguish yaws from syphilis however, and the interpretation of results from these tests in adults who live in yaws endemic areas needs careful clinical assessment because of syphillis.

Rapid point-of-care tests that can be used in the field are widely available.
However, most of them are treponemal-based and cannot distinguish between past and current infection. Recently dual treponemal and nontreponemal rapid tests have become available, thus simplifying diagnosis in the field. These tests are able to detect both present and past infections to guide treatment of people with active infection.