The most common screening test is the RPR, rapid plasma reagin. The antibody response will begin to show in the test just a few weeks after the exposure, but it is recommended to wait 3 months from the last exposure for more accurate test results. The tests will first show a positive result during primary syphilis and will remain positive unless a person receives treatment. About 12 months after treatment, the test results will usually return to normal. Although syphilis may not be the most common STD, the potential complications of untreated syphilis should be enough to initiate testing. All reactive RPRs are confirmed by an FTA-ABS test.
