title: Increasing sexually transmitted infection rates in young men having sex with men in the Netherlands, 2006-2012.
abstract: BACKGROUND
  Men having sex with men (MSM) remain the largest high-risk group involved in on-going transmission of sexually transmitted infections (STI), including HIV, in the Netherlands. As risk behaviour may change with age, it is important to explore potential heterogeneity in risks by age. To improve our understanding of this epidemic, we analysed the prevalence of and risk factors for selected STI in MSM attending STI clinics in the Netherlands by age group.
  
  
  METHODS
  Analysis of data from the national STI surveillance system for the period 2006-2012. Selected STI were chlamydia, gonorrhoea, infectious syphilis and/or a new HIV infection. Logistic regression was used to identify factors associated with these selected STI and with overall STI positivity. Analyses were done separately for MSM aged younger than 25 years and MSM aged 25 years and older.
  
  
  RESULTS
  In young MSM a significant increase in positivity rate was seen over time (p < 0.01), mainly driven by increasing gonorrhoea diagnoses, while in MSM aged 25 and older a significant decrease was observed (p < 0.01). In multivariate analyses for young MSM, those who were involved in commercial sex were at higher risk (OR: 1.5, 95% CI: 1.2-1.9). For MSM aged 25 years and older this was not the case. Having a previous negative HIV test was protective among older MSM compared to those not tested for HIV before (OR: 0.8, 95% CI: 0.8-0.8), but not among younger MSM.
  
  
  CONCLUSIONS
  MSM visiting STI clinics remain a high-risk group for STI infections and transmission, but are not a homogenous group. While in MSM aged older than 25 years, STI positivity rate is decreasing, positivity rate in young MSM increased over time. Therefore specific attention needs to be paid towards targeted counselling and reaching particular MSM sub-groups, taken into account different behavioural profiles.
authors.affiliation: Centre for Infectious Disease Control, RIVM National Institute of Public Health and the Environment, P.O. Box 1, 3720 BA Bilthoven, Utrecht, The Netherlands ; Municipal Health Service Twente, Enschede, The Netherlands.
authors.forename: Femke Dh
authors.initials: FD
authors.lastname: Koedijk
authors.affiliation: Centre for Infectious Disease Control, RIVM National Institute of Public Health and the Environment, P.O. Box 1, 3720 BA Bilthoven, Utrecht, The Netherlands.
authors.forename: Birgit Hb
authors.initials: BH
authors.lastname: van Benthem
authors.affiliation: STI AIDS Netherlands, Amsterdam, The Netherlands.
authors.forename: Eliane Mdc
authors.initials: EM
authors.lastname: Vrolings
authors.affiliation: STI AIDS Netherlands, Amsterdam, The Netherlands.
authors.forename: Wim
authors.initials: W
authors.lastname: Zuilhof
authors.affiliation: Centre for Infectious Disease Control, RIVM National Institute of Public Health and the Environment, P.O. Box 1, 3720 BA Bilthoven, Utrecht, The Netherlands ; Julius Center for Health Sciences and Primary Care, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: Marianne Ab
authors.initials: MA
authors.lastname: van der Sande
keywords: Adolescents; Commercial sex; Epidemiology; Ethnicity; Gay men; Surveillance