False positive results in V D R L slide test following smallpox immunization

A study is conducted on the incidence of false positive results in the serological test for syphilis in 300 military recruits following smallpox immunization. It is found that 3.7% of individuals developed false reactivity in the V D R L Slide test. The false reactivity appeared two to four weeks following immunization, and disappeared from two to eight weeks later. All reactive sera were negative in the FTA-ABS test.