Control and Prevention of Sexually Transmitted Infections; Chlamydia trachomatis. Dr Nathalie Broutet Department of Reproductive Health and Research

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1 Control and Prevention of Sexually Transmitted Infections; Chlamydia trachomatis Dr Nathalie Broutet Department of Reproductive Health and Research

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3 Intervention Effects Level Levels at which STI have their effects Individual Sexual partner or unborn child Population Acute symptoms Infertility Cervical cancer HIV acquisition Neurological and CV disease Recurrent HSV Counselling Condoms Vaccines Male circumcision Vaginal microbicides Diagnostic tests Syndromic management ATB / antivirals STI transmission Facilitate HIV transmission Ophthalmia neonatorum Neonatal pneumonitis Congenital syphilis Neonatal HSV encephalitis Stillbirth PRM Partner notification ANC syphilis screening Adequate Tx of STI to prevent HIV and STI trans Epidemic Continuing transmission of STI Exacerbation of HIV epidem Primary prevention programme Periodic presumptive treatment Screening opportunities to be evaluated (targeted services, SRH clinic, STI clinic?) Vaccination programme Source. Low et al. Lancet 2006

4 STI Global Burden Global estimated total of STIs, incidence per region 2005

5 STI Global Burden Global estimated total of selected STIs, incidence per STI and region 2005

6 Transmission of STIs

7 Global strategy for the prevention and control of sexually transmitted infections: Breaking the chain of transmission

8 Transmission Dynamics Model with Intervention Opportunities for the Control of STIs Transmission dynamics Strategies Intermediate outcome Ultimate impact Sex Workers Clients Targeted interventions Increased condom use in commercial sex Reduced prevalence of STIs Regular partners Enhanced STI prevention & Quality Case Management Increased condom use in general population Reduced HIV/STI incidence

9 STI Guidance to Expand Coverage

10 Prevention in General Population Promoting Healthy Sexual Behavior: Correct and Consistent use of male and female condoms Delay in onset of sexual activity Keeping to one sexual partner or reducing the number of sexual partners Abstinence Communication is crucial: - Peer educators - Opinion leaders -Schools and other arenas Identify strategies to reach the high-risk population

11 Primary prevention of infection No vaccines available against bacterial infections : progress but no products Vaccines available against viral infections: HIV clinical trials HSV 2 trials HepB vaccines available HPV vaccines available

12 STI Guidance to Expand Coverage

13 Syndromic Management STIs can be managed through consistently recognized signs and symptoms shown in flowcharts that can be accessed at the primary health clinic level *Urethral Discharge Flow Chart. Digital image. Ministry of Health Ghana, Web. 8 Mar <

14 Accurate Treatment is Necessary: Prevalence and trends of ciprofloxacinresistance in Neisseria gonorrhoeae Africa ( ) Courtesy: David Lewis Hawaii ( ) Argentina Peru Canada Uruguay Canada ( )

15 Asymptomatic STI Population with STI Have symptoms Seeking care Correct diagnosis Correct treatment Treatment completed Cure

16 Sexually Transmitted Infections Most prevalent high-risk sexual behavior populations: Adolescent and Sex workers Symptomatic Cases Asymptomatic Cases Ex.: 70-75% of all Chlamydia cases are asymptomatic!

17 Incidence Estimated New Cases of Genital Chlamydia Infections (WHO, 2005) Estimated New Cases of Genital Chlamydia Infections (WHO, 2005) AMRO EURO EMRO AFRO SEARO WPRO Regions Total Number of Cases Female Male Female Male Total

18 Age-Specific Incidence Rate (per 100,000) Age and Sex-Specific Rate of Chlamydia Infections WPRO, Mid-West Ireland, ** Male Female USA, 2006* M e n R a t e ( p e r 1 0 0, p o p u la t io n ) W o m e n A g e Age T o t a l *Chlamydia Age- and Sex-specific Rates: United States, Digital image Sexually Transmitted Diseases Surveillance. Centers for Disease Control and Prevention, 13 Nov Web. 8 Mar < **Whyte D, Powell J, Horgan M, O Connell N, FitzGerald R, Monahan R, Greally T. Trends in genital chlamydia infection in the Mid-West of Ireland, Euro Surveill. 2007;12(10):pii=741. Available online: 18

19 Chlamydia trachomatis Infection Long term consequences Reproductive tract sequelae: PID Tubal factor infertility Ectopic pregnancy Control programmes Reduce transmission Screening asymptomatic prevalent infection in young sexual active women Effort to treat male partners Screen women for reinfection number of adverse outcomes of infection

20 Impact at individual level Impact at population level Depends on: - Damage relative to acquisition of infection (tubal) - Mean duration of infection when screened Decrease of the mean duration of infection: -reduce nb of complications and transmission - decrese nb of new infections Benefits on tubal damage by detecting infection Susceptibility to new repeat infections And their risk of sequelae Potential increase of repeat infections if - ttt partners -screening for reinfection is low

21 Burden of Recurrent Chlamydia Infections in Adolescent Populations (Connecticut, USA ) *Recurrence rates are almost as equal as initial rates of infection Hypothesis: Do misperceptions of the risk in relationships exist? Is there consistent and correct use of condoms? Is the timing of treatment too early in age? Are partners being effectively treated? Niccolai, L. M., A. L. Hochberg, K. A. Ethier, J. B. Lewis, and J. R. Ickovics. "Burden of Recurrent Chlamydia Trachomatis Infections in Young Women: Further Uncovering the "Hidden Epidemic"" Archives of Pediatrics and Adolescent Medicine (2007): American Medical Association, Web. 9 Mar <Burden of Recurrent Chlamydia trachomatis Infections in Young Women>.

22 Inverse Relationship Between Age and Chlamydia Infection AGE Chlamydia BIOLOGICAL Cervical ectopy (present in adolescents) is linked to higher infection rates IFN-γ messenger RNA transcripts are found in older persons (provides immunity) Organism load is greater in younger persons + BEHAVIORAL and year age groups are peak intervals for having 2 sex partners Riskier sexual behaviors Source: Protective Immunity to Chlamydia trachomatis Genital Infection: Evidence from Human Studies, The Journal of Infections Diseases 2010; 201 (S2):S178-S189

23 Current Responses Treatment Based on Prevalence Among ANC, Vanuatu Treatment based on prevalence (>= 20%) ANC women Issue partner tx CT screening - BD Probe tec Low lab capacity (quality) Limited staff Low coverage Low treatment rate no drugs, long turn around time for results Drop in centre for vulnerable population Epi tx. ANC ANC CT screening Source: Pacific SGS Surveys available at:

24 Sex Workers: Targeted Interventions Outreach and peer education 100% CUP Policy Involvement of brothel/ estbalishment owners Increase condom access Monitoring STI services drop in services Initial presumptive treatment STI syndromic treatment Regular STI check-ups

25 % Prevalence % Condom Use 100% Condom Use Programme Wuhan China, Condom Use Chlamydia 0 Baseline Months 0 Chen Zhongdan et.al, 2007

26 % Prevalenc Impact of Presumptive Treatment and Condom Use in Philippines, 2001 Findings of study show that interventions are effective. Must MAINTAIN ongoing STI screening for SUSTAINED STI reductions Baseline (Mo. 0) R2 (Mo. 1) R3 (Mo. 7) All Sex Worker Groups Registered Sex Workers Street Sex Workers Brothel Sex Workers Wi, T. "STI Declines among Sex Workers and Clients following Outreach, One Time Presumptive Treatment, and Regular Screening of Sex Workers in the Philippines." Sexually Transmitted Infections 82.5 (2006): PubMed Central. BMJ Publishing Group. Web. 8 Mar <

27 Interventions for 25 Population Screening and Rescreening of Previously Infected Persons Partner treatment Health education and Outreach Education Access to male and female condoms Partner treatment efforts Behavioral Modifications Access to Services One-stop shops, multi-purpose youth health centers, age-appropriate school-based services Mobile clinics? Strengthened Surveillance Data stratified by age and sex

28 Main issue Sustainability of the interventions to maintain impact If: Screening and treatment + Invest in preventing reinfection Partners treatment Condom use

29 Acknowledgments Research needs: - POC screening tools - Infection clearance and persistence - Pathogenesis - Protective immunity against infection Guest Editor: Sami L. Gottlieb Intern: Melody Maarouf The JID, vol. 201, suppl. 2, 15 June 2010