Rapid decrease of endemic gonorrhea in Finland

The incidence of gonorrhea has decreased in several European countries while a recent epidemic has occurred in Russia and the Baltic countries. In 1990, Finland had a higher gonorrhea incidence than the other Nordic countries. Therefore we studied prospectively the epidemiology of gonorrhea with special reference to the endemic or imported source of infection.

The study included three gonorrhea patient series from STD clinics in Helsinki in 1990 to 1995. Each series covered a 12-month period. Case controls with Chlamydia trachomatis infection were included. Demographic and epidemiological findings, including source partner profiles, were analyzed.

Gonorrhea decreased rapidly during the study period. In 1990 to 1991, there were 490 patients (3.3% of all patient visits); in 1992 to 1993, 162 (1.3%); and in 1994 to 1995, only 92 patients (0.9%) with gonorrhea. The change in the prevalence was highly significant (p < 0.0001) and was entirely because of the decreased number of endemic infections. The rate of imported gonorrhea remained constant with 50 to 60 patients, although traveling had increased markedly to Russia and Estonia where the incidence of gonorrhea was very high. Thirty-one percent of the patients with endemic gonorrhea but only 14% with imported gonorrhea (p < 0.0001) had a concomitant C. trachomatis infection. The prevalence of chlamydia decreased from 10.2 to 8.1% (p < 0.001), but in contrast to gonorrhea the source of infection was mainly endemic (89% to 97%) during the whole study period. The patients with gonorrhea were older and had a higher frequency of casual source partners than those with chlamydia. Overall, from 80% to 74%) of the men and from 48% to 33% of the women had contracted infection from a casual partner.

The present study documented a rapid decrease of endemic gonorrhea in Finland, whereas the rate of imported gonorrhea remained constant. Demographic findings or source partner profiles of patients with gonorrhea or chlamydia gave no obvious explanation for the rapid decline of endemic gonorrhea, which is in sharp contrast to C. trachomatis infection.