Chlamydia among youth in Stockholm : testing habits and evaluation of a mobile phone intervention to promote safe sexual practices

Sammanfattning: Background. The World Health Organization (WHO) estimates that 350 million new cases of curable sexually transmitted infections (STIs) occur each year. Prevention of STIs include both primary and secondary prevention strategies: sexual education, condom distribution, testing and treatment services. Sweden has a long tradition of widespread testing for Chlamydia Trachomatis (C.trachomatis), an opportunistic screening approach. Sexual education in school is mandatory and a national network of Youth Health Clinics (YHC) enables health care access for youth. Still, infection rates of C.trachomatis have increased over the past decades since opportunistic screening was introduced, and moreover continue to stay high. In addition, national surveys indicate low condom use among youth. The overall aim of this thesis was to look deeper into the screening services to understand why this approach does not seem to have the sought for effect and to compare the effectiveness of a mobile phone application to improve sexual health among youth of Stockholm County in addition to routine care offered at the YHCs. Methods and Results. Study I: Register based study performed from data obtained from three laboratories in Stockholm County. All tests for C.trachomatis done at the YHCs in Stockholm over a three year period were included in the study. The aim of the study was to describe testing behavior for genital C.trachomatis among youth in Stockholm County. Specifically to (1) study positivity rates among single and repeat testers, (2) to estimate the incidence of repeat testing and the rates of infection on repeat testing episodes and (3) to estimate time to repeat testing and factors associated with repeat testing. In total 65 951 persons underwent 119 699 tests. Repeat testing was found among 42% of all study participants included in the study (ranging from 2 to 18 tests). Higher rates of C.trachomatis among repeat testers compared to single testers were found at baseline, especially among men. Incidence of repeat testing was higher than previously reported. Study II: A qualitative study. We interviewed 15 repeat testers at the YHCs about motives behind testing repeatedly and subsequent sexual risk-taking. Data was analyzed using a constructivist grounded theory approach. We found that youth perceive repeated testing for C.trachomatis equally protective as using a condom. The testing episode, test result or encounter with the clinic personnel did not steer sexual health preferences towards more protective sexual practices. A major motivation for the retesting process was the fear of infecting a peer leading to social stigma. The results of this study provide new information that will allow the C.trachomatis screening programs to introduce more appropriate interventions for youth retesting frequently and to streamline routines. In addition, lessons learned from our study could be helpful in other screening programs with high re-testing rates. Study III: Interview study. Twelve health care providers in YHCs in Stockholm were interviewed to explore their views on the practice of youth repeatedly testing for C.trachomatis ‘to stay safe and clean’. A content analysis approach was used to analyze data. Health care providers’ expressed appreciation for the easy-access testing services, as it facilitated individual sexual health counselling. Testing without having time to interact and reflect together with the youth was not perceived as meaningful. Findings from this study could strengthen ongoing preventive work thus involving the experience and expertise of daily care youth health care provider’s. Study IV: Randomized controlled trial (RCT). We aimed to complement and strengthen primary prevention strategies using a mobile phone intervention, (mHealth) given their popularity with youth. Following focus group discussions with young people, we developed a youth friendly smart phone application. The aim was to increase condom use and promote safe sex. The effect of the intervention was evaluated in a two arm parallel group pragmatic RCT; "The MOSEXY trial” (MObile Phone intervention for SEXual health in Youth). At time of inclusion, consistent condom use was reported by 1/10 of participants. Condom use increased in both arms however with no differences between the groups. In addition, number of sexual partners, frequency of re-testing and occurrence of STIs did not differ among the groups. Conclusion. On an individual level, easy and prompt access to testing services is important in order to interrupt transmission of STIs and treat infections. At the same time secondary prevention strategies must not undermine primary prevention strategies aiming to improve sexual health in means of avoiding infections by condom use. A mHealth intervention did not increase condom use among youth in our setting. However, mHealth for sexual health has the potential to reach large group of youth effectively.