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Tom Oluoch, on behalf of the KAIS TWG March 2 nd , 2009 Bangkok, Thailand. Utility of additional biologic tests in a nationally representative HIV survey. History of HIV Surveillance in Kenya. Antenatal sentinel surveillance 1990-2006 (currently 43 sites)
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Tom Oluoch, on behalf of the KAIS TWGMarch 2nd, 2009Bangkok, Thailand Utility of additional biologic tests in a nationally representative HIV survey
History of HIV Surveillance in Kenya • Antenatal sentinel surveillance 1990-2006 (currently 43 sites) • STI patient sentinel surveillance 1990-2006 • National Demographic and Health Surveys 1998, 2003 with HIV finger stick testing • AIDS Indicator Survey 2007 with venous blood draw • 1st AIS • 2nd pop-based HIV sero-survey, in Kenya
KAIS Design • Stratified two-stage cluster sample design • 8 provinces, urban and rural areas • Eligibility: • HH sample: usual residents/visitors night before survey • Individual sample: Men and women age 15-64 from participating households • Reported estimates weighted to account for sampling • Informed consent for interview, blood draw, sample storage
Utility of HSV-2 and Syphilis Data • Monitor known risk factors for acquisition and transmission of HIV infection • Syphilis (associated with 2.5 times increase in HIV prevalence) • HSV-2 (associated with 8 times increase in HIV prevalence) • Results imminent on the effects of treatment of people with HIV/HSV-2 co-infection to prevent HIV transmission– Kenya is a trial country. • Inform upcoming revisions to STI clinical management guidelines
Utility of CD4 data • In this era of prevention, care & Rx scale-up, HIV status, knowledge of status, ART use and CD4 are necessary to interpret the epidemic • Guiding policy decisions on treatment • Estimating current and future need for care and treatment. • Additional information on new and old HIV infections. • Planning resources for care and Rx.
National Repository for Future Testing • DBS, serum and clot specimens stored at -80oC • >99.9% of participants consenting to blood draw, also consented to storage • Resources and policies required upfront to guide ownership, access and use. • Potential Utilization: • Monitoring drug resistance over time • Looking at HIV incidence • System strengthening for the country (other infectious and non-infectious diseases).
New Questions on Status and Behavior • Knowledge of HIV status - self and sexual partners • 98% of those ever tested for HIV agreed to disclose result of last HIV test • Partner specific behavior, including partner status and disclosure between partners. • When used with other indicators (condom use, lab confirmed HIV status), these new questions help to identify important gaps in services and patterns of acquisition and transmission • History of use of Cotrimoxazole and ART
Sample Results KAIS 2007
Overall Response Rates Households interview: 97% Individuals interview: 91% Blood draw: 80% (88% of those interviewed vs. 77% in DHS 2003) Sample size for analysis: • 9,691 – households • 17,940 – individual interview • 15,853 – blood draw
HIV Prevalence by Gender 2007 KAIS indicates that 7.1%, or about 1.3 million Kenyans age 15-64 are infected with HIV.
HSV-2 Prevalence & Co-infection • National prevalence: 35.1%(6.7 million adults, 15-64) • HIV was 8 times more common in HSV-2 infected than HSV-2 uninfected persons (16.4% vs. 2.1%) • 80.7% of HIV-infected persons were infected with HSV-2, 2.5 times the prevalence in HIV-uninfected persons (31.6%)
Syphilis Prevalence & Co-infection • National prevalence: 1.8%(342,000 adults, 15-64) • Women: 1.7% Men: 1.9% • Syphilis was 2.5 more common in those with HIV-infection than HIV-unifected persons (4.2% vs. 1.6%) • 16.9% of HIV-infected persons were infected with syphilis, 2.5 times the prevalence in HIV un-infected persons (6.9%)
Knowledge of HIV Status among HIV-infected KAIS Participants 16% knew they were positive 56% never tested for HIV 28% reported last HIV-test negative 84% of HIV-infected adults did not know their status. Denominator: Lab-confirmed HIV infected participants (2% missing data on HIV testing history or known HIV status; 1% chose not to disclose status)
Coverage of Cotrimoxazole 12% Know status, on CTX Among those who knew their status, 75% on cotrimoxazole 4% Know status, not on CTX 84% Unaware of status*, not on CTX Denominator: Lab-confirmed HIV infected participants * Never tested for HIV, reported uninfected based on last HIV test
Coverage of ART among Eligible HIV-infected Persons Among those who knew status and were eligible, 92% on ART 39% Know status, on ART 57% Unaware of status*, not on ART 4% Know status, not on ART Denominator: Lab-confirmed HIV-infected persons with CD4<250 and not on treatment plus those who reported ART use * Never tested for HIV, reported uninfected based on last HIV test
CD4 Cell Count Distribution among HIV-infected Adults not on ART
Challenges • Syphilis: Interpretation of results presents challenge. Visual interpretation is subjective. • Developing counseling messages on HSV-2 used for returning results to participants. • Careful planning for logistics: sample transportation and short turn-around time for CD4 testing (7 days). • Timely return of results to participants
Conclusions • HSV-2 and syphilis remain major risk factors in HIV acquisition among Kenyan adults • Biologic indicators, used together with behavioral data are necessary for interpreting the epidemic. • Critical for policy and program planning • Its feasible in diverse geographic region • Additional biological indicators did not negatively impact participation rates