BACKGROUND: Since 1995, the incidence of Chlamydia trachomatis infection has been increasing in Finland, although there have been no major changes in public sexually transmitted disease (STD) services or screening practice. OBJECTIVES: The objective was to study whether the change in C. trachomatis incidence is significant and to identify specific risk groups. METHODS: The incidence rates for all C. trachomatis cases notified by laboratories to the National Infectious Disease Register (NIDR) in Finland in 1995-2000 were calculated by gender, age, and domicile. Data from a sentinel STD surveillance network was used to analyze changes of risk-taking behavior in age groups with the highest C. trachomatis rates. RESULTS: During the 6-year study period, laboratory surveillance data documented an increase in the incidence rate from 23.4 per 10,000 to 29.2 per 10,000. The increase was most evident among people living in nonurban densely populated areas. Highest increase, 1.37-fold (95% confidence interval [CI], 1.29-1.46) in women and 1.69-fold (CI, 1.47-1.92) in men, occurred in the youngest age group (10-19 years old). In 2000, more women, but not men, in the age group of 10-29 years reported 5 or more annual sex partners (18.8%; CI, 16.3-21.6) than in 1995 (8.3%; CI, 5.7-11.5). CONCLUSION: National surveillance of C. trachomatis infection based on laboratory notification documented increasing incidence rates, especially among adolescents and young people. This risk group should be a target for screening and educational programs to control the epidemic of C. trachomatis infections.
BACKGROUND: Since 1995, the incidence of Chlamydia trachomatis infection has been increasing in Finland, although there have been no major changes in public sexually transmitted disease (STD) services or screening practice. OBJECTIVES: The objective was to study whether the change in C. trachomatis incidence is significant and to identify specific risk groups. METHODS: The incidence rates for all C. trachomatis cases notified by laboratories to the National Infectious Disease Register (NIDR) in Finland in 1995-2000 were calculated by gender, age, and domicile. Data from a sentinel STD surveillance network was used to analyze changes of risk-taking behavior in age groups with the highest C. trachomatis rates. RESULTS: During the 6-year study period, laboratory surveillance data documented an increase in the incidence rate from 23.4 per 10,000 to 29.2 per 10,000. The increase was most evident among people living in nonurban densely populated areas. Highest increase, 1.37-fold (95% confidence interval [CI], 1.29-1.46) in women and 1.69-fold (CI, 1.47-1.92) in men, occurred in the youngest age group (10-19 years old). In 2000, more women, but not men, in the age group of 10-29 years reported 5 or more annual sex partners (18.8%; CI, 16.3-21.6) than in 1995 (8.3%; CI, 5.7-11.5). CONCLUSION: National surveillance of C. trachomatis infection based on laboratory notification documented increasing incidence rates, especially among adolescents and young people. This risk group should be a target for screening and educational programs to control the epidemic of C. trachomatis infections.
Authors: Elena Regushevskaya; Tatiana Dubikaytis; Made Laanpere; Minna Nikula; Olga Kuznetsova; Hele Karro; Elina Haavio-Mannila; Elina Hemminki Journal: Int J Public Health Date: 2010-06-30 Impact factor: 3.380