Social-, age- and gender differences in testing and positive rates for Chlamydia trachomatis urogenital infection – a register-based study

Background: Chlamydia Trachomatis (CT) is suspected of causing female infertility. It is the most widespread STD with an estimated general prevalence of about 5-10 % with a peak in younger individuals.CT infection is more prevalent among lower social classes.
Objective: In this study the association between age, gender, social status, and testing and positive rates is investigated in the age group 15-24 years.
Design: Case-control study linked to data from Statistics Denmark.
Methods: Data from the Department of Microbiology, Hvidovre University Hospital, Copenhagen was used and included 21,887 people tested by general practitioners (GPs) and 3,177 people tested at a venereological clinic (VC). The age range was 15-24 years in 2011. These data were linked with the parental educational status delivered by Statistics Denmark, which also delivered a matched control group. The data were analyzed using a case-control design.
Results: Testing was more frequent in the following groups: age range 20-24 years, females and patients with higher parental educational status. 87.3% of patient had been tested by GPs. Positive rates were highest among males at the GP: 17.1% vs. 10.6%, younger individuals and patients with lower parental educational status.
Conclusions: The pattern CT testing and positive rates highlights a need for a greater focus on males, younger patients and individuals with a lower social status.