Recorded gonorrhoea rates in Denmark, 1900–2010: the impact of clinical testing activity and laboratory diagnostic procedures

摘要

Objectives Assessment of the relations between recorded gonorrhoea rates and clinical testing activity and disposable diagnostic tests. Methods In Denmark, two sources of information on the epidemiology of gonorrhoea are available: (1) a mandatory clinical notification system (since 1867) comprising summary information about geographic distribution, season, age group and gender; in 1994, more detailed anonymous individualised epidemiological information was included; (2) a voluntary countrywide laboratory surveillance system for culture-confirmed cases (since 1957) comprising information about patient's age and gender, infected anatomical sites and medical setting attended. Results Both surveillance systems showed marked simultaneous changes in gonorrhoea rates, although periodically considerable under-reporting or under-diagnosing was demonstrated. The annual incidence of notified cases peaked in 1919 (474/100?000), in 1944 (583/100?000) and in 1972 (344/100?000). Since 1995, the incidence has been at a low endemic level (1.5–10/100?000) and the total male/female incidence ratios were from 3 to 7 times higher than previously recorded. Among approximately 2 million persons tested during 1974–1988 78?213 men and 63?143 women with culture-confirmed gonorrhoea were identified. During this period, pharyngeal sampling was performed in 36% of men and 25% of women with gonorrhoea; pharyngeal gonorrhoea was found in 10% and 16%, respectively; 40% and 30% of these patients had no concomitant urogenital gonorrhoea. Among men with gonorrhoea, 34% were sampled from the rectum; 9% had rectal gonorrhoea, among whom the rectum was the only infected site in 67%. Conclusions Crucial factors for case finding are clinical sampling tradition and appropriate laboratory diagnostic facilities. When case finding is insufficient, a reservoir of asymptomatic rectal or pharyngeal gonorrhoea remains unrecognised.