Molecular epidemiology of syphilis in Scotland

Abstract

OBJECTIVE: To examine the molecular epidemiology of syphilis in Scotland. METHODS: Ulcer specimens were collected from 85 patients with infectious syphilis. Typing of Treponema pallidum was performed using a method that examines variation in two loci; the number of 60-basepair repeats within the arp gene and sequence variation in the tpr genes. RESULTS: Patients were predominately white men who have sex with men (MSM). Treponemal DNA was detected in 75 specimens and a total of six subtypes were identified from 58 typeable specimens (77%). The most common subtypes were 14d (44/58, 76%), followed by 14e (7/58, 12%), 14j (3/58, 5%), 14b (2/58, 3%), 14p and 14k (1/58, 2%). CONCLUSIONS: This study shows that subtype 14d is the predominant subtype circulating in Scotland and there is a surprising level of genetic diversity within the Scottish MSM community.