Prevalence of Chlamydia trachomatis and herpes simplex virus type 2: Results from the 2009 to 2011 Canadian Health Measures Survey.

ABSTRACT

BACKGROUND: Chlamydia, caused by Chlamydia trachomatis, and genital herpes, caused by simplex virus type 2 (HSV-2), are common sexually transmitted infections. Their prevalence has been estimated in selected populations, but overall prevalence in Canada is not known. DATA AND METHODS: Data are from the 2009 to 2011 Canadian Health Measures Survey. Socio-demographic, health and lifestyle information was obtained via a household questionnaire; blood and urine collected at a mobile examination centre were used to identify the presence of Chlamydia trachomatis and HSV-2 among 14- to 59-year-olds. RESULTS: An estimated 13.6% of Canadians (2.9 million) tested positive for HSV-2, and another 0.7% (158,000), for chlamydia. HSV-2 affects higher percentages of women than men, and individuals aged 35 to 59 versus 15 to 34. No significant differences in HSV-2 prevalence were detected by marital status, household income, education, or racial background. Nearly all individuals with laboratory-confirmed chlamydia or HSV-2 were unaware that they were infected. INTERPRETATION: This study is the first in Canada to report laboratory-confirmed prevalence of chlamydia and HSV-2 using a nationally representative sample. Results suggest that most infected people are unaware of their status.