Keywords: Chlamydia trachomatis, load, STD, STD testing, symptoms

"The Chlamydia trachomatis bacterial load"

Chlamydia trachomatis (CT) is the most common cause of bacterial sexually transmitted disease (STD) worldwide. Although CT may be asymptomatic, it may also cause infertility. In other STDs such as HIV and gonorrhoea, the load, i.e. the number of microorganisms, is associated with symptoms and complications. Therefore, we studied whether this association also exists in CT. In women, a high load was not associated with symptoms. In men, a high load was only associated with penile discharge. We also studied the load during the diagnosis-to-treatment interval to explore its natural course. During this interval, a stable or decreasing load was found instead of an increasing load, which may indicate the onset of an infection. These results suggest that people can be tested for CT soon after having unsafe sex, probably within the usual two weeks. Finally, we studied the CT load in genital and anal samples of the same woman. We compared this to the CT load in anal samples of men who have sex with men (msm). The load in anal samples of msm is the same as the load in anal samples of women reporting anal sex. The load in anal samples of women who do not have anal sex is slightly lower, yet still in the same range. In these women, self-contamination with a genital infection could not be demonstrated, nor excluded.