Syphilis 2017

Syphilis 2017

In 2017, the national monitoring scheme, stewarded by Statens Serum Institut (SSI), recorded 545 cases of syphilis in 521 persons. 
A total of 487 (89%) of the cases occurred in 463 men and 58 (11%) in 58 women, as 24 men had two cases in the course of the year.

The median age was 41 years for men (range 18-86 years) and 30 years for women (range 19-58 years), Table 1.


A total of 326 (60%) of the cases, 284 men and 42 women, were reported to the Notification System for Infectious Diseases (NSID), the Department of Infectious Disease Epidemiology and Prevention (DIDEP). A total of 219 (40%) cases had not been notified to the NSID.

As in previous years, the majority of the patients resided in the Copenhagen area, Table 2.


The total number of cases registered in 2017 was somewhat lower than the preceding year (742), Table 2. However, the number of notified cases was in line with the previous year (317). Thus, the increase observed for a number of years has halted, Figure 1.

Congenital syphilis and syphilis in pregnant women

Among the 58 syphilis cases that were detected in women, 10 were found owing to the pregnancy screening. In one of these cases, no notification had been made to the NSID. Eight of the pregnant women were of Danish origin, one was from Romania and one from the Ivory Coast.

One of the notified pregnant women was a known IV drug user.


Among the 284 notified persons, 65 were men notified as heterosexual transmission cases (23% of all notified men), 210 were notified as men who have sex with men (MSM, 74% of the notified men); and in 9 cases, the mode of transmission was not stated (3% of the notified men). A total of 42 women were notified, all due to heterosexual transmission (13% of those notified). Figure 1 presents the number of persons notified with sexually transmitted syphilis since 2000.


Among the 326 cases in which origin was stated, 245 (75%) were of Danish origin, 72 (22%) were immigrants, seven were second-generation immigrants and two were tourists. The number of persons who had not been born in Denmark totaled 74 from 38 different countries around the globe.

The country of transmission was stated for 269 (83%) of those who had been notified, 234 men and 35 women. A total of 200 (85%) men and 29 women (83%) had become infected in Denmark. In all, 25 (86%) of the women who had become infected in Denmark were of Danish origin. Among heterosexually infected men for whom the country of transmission was stated, 30 of 37 (81%) had become infected in Denmark, while this was the case for 140 of 163 (86%) of the MSM.

Syphilis and HIV

Information about HIV status was available for 271 (95%) men and for 39 women (93%).

Among HIV-tested men, 75 (28%) were HIV positives. There were 71 HIV positives among the 202 MSM (35%), 2 (3%) among the 62 men who were notified as heterosexually infected and 2 (33%) among the six men for whom sexual orientation was not stated. Among the 75 HIV-positive men, 11 (15%) had been diagnosed with HIV and syphilis simultaneously (all MSM), whereas 64 (85%) were known HIV positives prior to their current syphilis diagnosis (60 MSM, 2 heterosexuals and in 2 cases the sexual orientation was not stated). No women were notified as being HIV positives.

This report is described in EPI-NEWS 22/18.