Background Enhanced HIV surveillance using demographic, behavioral, and biologic data from national surveys can provide information to evaluate and respond to HIV epidemics efficiently. Methods From October 2012 to February 2013, we conducted a 2-stage cluster sampling survey of persons aged 18 months to 64 years in 9 geographic regions in Kenya. Participants answered questionnaires and provided blood for HIV testing. We estimated HIV prevalence, HIV incidence, described trends in HIV prevalence over the past 5 years, and identified factors associated with HIV infection. This analysis was restricted to persons aged 15–64 years. Results HIV prevalence was 5.6% [95% confidence interval (CI): 4.9 to 6.3] in 2012, a significant decrease from 2007, when HIV prevalence, excluding the North Eastern region, was 7.2% (95% CI: 6.6 to 7.9). HIV incidence was 0.5% (95% CI: 0.2 to 0.9) in 2012. Among women, factors associated with undiagnosed HIV infection included being aged 35–39 years, divorced or separated, from urban residences and Nyanza region, self-perceiving a moderate risk of HIV infection, condom use with the last partner in the previous 12 months, and reporting 4 or more lifetime number of partners. Among men, widowhood, condom use with the last partner in the previous 12 months, and lack of circumcision were associated with undiagnosed HIV infection. Conclusions HIV prevalence has declined in Kenya since 2007. With improved access to treatment, HIV prevalence has become more challenging to interpret without data on new infections and mortality. Correlates of undiagnosed HIV infection provide important information on where to prioritize prevention interventions to reduce transmission of HIV in the broader population.

Background HIV testing and counseling (HTC) is essential for successful HIV prevention and treatment programs. The national target for HTC is 80% of the adult population in Kenya. Population-based data to measure progress towards this HTC target are needed to assess the country’s changing needs for HIV prevention and treatment. Methods In 2012–2013, we conducted a national HIV survey among Kenyans aged 18 months to 64 years. Respondents aged 15–64 years were administered a questionnaire that collected information on demographics, HIV testing behavior, and self-reported HIV status. Blood samples were collected for HIV testing in a central laboratory. Participants were offered home-based testing and counseling to learn their HIV status in the home and point-of-care CD4 testing if they tested HIV-positive. Results Of 13,720 adults who were interviewed, 71.6% [95% confidence interval (CI): 70.2 to 73.1] had been tested for HIV. Among those, 56.1% (95% CI: 52.8 to 59.4) had been tested in the past year, 69.4% (95% CI: 68.0 to 70.8) had been tested more than once, and 37.2% (95% CI: 35.7 to 38.8) had been tested with a partner. Fifty-three percent (95% CI: 47.6 to 58.7) of HIV-infected persons were unaware of their infection. Overall 9874 (72.0%) of participants accepted home-based HIV testing and counseling; 4.1% (95% CI: 3.3 to 4.9) tested HIV-positive, and of those, 42.5% (95% CI 31.4 to 53.6) were in need of immediate treatment for their HIV infection but not receiving it. Conclusions HIV testing rates have nearly reached the national target for HTC in Kenya. However, knowledge of HIV status among HIV-infected persons remains low. HTC needs to be expanded to reach more men and couples, and strategies are needed to increase repeat testing for persons at risk for HIV infection.

Background Cross-sectional population-based surveys are essential surveillance tools for tracking changes in HIV epidemics. In 2007, Kenya implemented the first AIDS Indicator Survey [Kenya AIDS Indicator Survey (KAIS) 2007)], a nationally representative, population-based survey that collected demographic and behavioral data and blood specimens from individuals aged 15–64 years. Kenya’s second AIDS Indicator Survey (KAIS 2012) was conducted to monitor changes in the epidemic, evaluate HIV prevention, care, and treatment initiatives, and plan for an efficient and effective response to the HIV epidemic. Methods KAIS 2012 was a cross-sectional 2-stage cluster sampling design, household-based HIV serologic survey that collected information on households as well as demographic and behavioral data from Kenyans aged 18 months to 64 years. Participants also provided blood samples for HIV serology and other related tests at the National HIV Reference Laboratory. Results Among 9300 households sampled, 9189 (98.8%) were eligible for the survey. Of the eligible households, 8035 (87.4%) completed household-level questionnaires. Of 16,383 eligible individuals aged 15–64 years and emancipated minors aged less than 15 years in these households, 13,720 (83.7%) completed interviews; 11,626 (84.7%) of the interviewees provided a blood specimen. Of 6302 eligible children aged 18 months to 14 years, 4340 (68.9%) provided a blood specimen. Of the 2094 eligible children aged 10–14 years, 1661 (79.3%) completed interviews. Conclusions KAIS 2012 provided representative data to inform a strategic response to the HIV epidemic in the country.

IntroductionSurveillance of recent HIV infections in national testing services has the potential to inform primary prevention programming activities. Focusing on procedures required to accurately determine recent infection, and the potential for recent infection surveillance to inform prevention efforts, we present the results of three independent but linked pilots of recency testing.MethodsTo distinguish recently acquired HIV infection from long‐standing infection, in 2018 we applied a Recent Infection Testing Algorithm that combined a laboratory‐based Limiting Antigen Avidity Enzyme Immunoassay with clinical information (viral‐load; history of prior HIV diagnosis; antiretroviral therapy‐exposure). We explored potential misclassification of test results and analysed the characteristics of participants with recent infection. We applied the algorithm in antenatal clinics providing prevention of mother‐to‐child transmission services in Siaya County, Kenya, outreach sites serving female sex workers in Zimbabwe, and routine HIV testing and counselling facilities in Nairobi, Kenya. In Nairobi, we also conducted recency testing among partners of HIV‐positive participants.ResultsIn Siaya County, 2.3% (10/426) of HIV‐positive pregnant women were classified as recent. A risk factor analysis comparing women testing recent with those testing HIV‐negative found women in their first trimester were significantly more likely to test recent than those in their second or third trimester. In Zimbabwe, 10.5% (33/313) of female sex workers testing HIV‐positive through the outreach programme were classified recent. A risk factor analysis of women testing recent versus those testing HIV‐negative, found no strong evidence of an association with recent infection. In Nairobi, among 532 HIV‐positive women and men, 8.6% (46) were classified recent. Among partners of participants, almost a quarter of those who tested HIV‐positive were classified as recent (23.8%; 5/21). In all three settings, the inclusion of clinical information helped improve the positive predictive value of recent infection testing by removing cases that were likely misclassified.ConclusionsWe successfully identified recently acquired infections among persons testing HIV‐positive in routine testing settings and highlight the importance of incorporating additional information to accurately classify recent infection. We identified a number of groups with a significantly higher proportion of recent infection, suggesting recent infection surveillance, when rolled‐out nationally, may help in further targeting primary prevention efforts.

Background: Serological tests can distinguish recent (in the prior 12 months) from long-term HIV infection. Integrating recency testing into routine HIV testing services (HTS) can provide important information on transmission clusters and prioritize clients for partner testing. This study assessed the feasibility and use of integrating HIV recency into routine testing. Methods: We conducted a multi-method study at 14 facilities in Kenya, and key informant interviews with health care providers. We abstracted clinical record data, collected specimens, tested specimens for recent infection, returned results to participants, and conducted a follow-up survey for those recently infected. Results: From March to October 2018, we enrolled 532 clients who were diagnosed HIV-positive for the first time. Of these, 46 (8.6%) were recently infected. Women aged 15–24 years had 2.9 (95% confidence interval: 1.46 to 5.78) times higher adjusted odds of recent infection compared with 15–24-year-old men and those tested within the past 12 months having 2.55 (95% confidence interval: 0.38 to 4.70) times higher adjusted odds compared with those tested ≥12 months previously. Fourteen of 17 providers interviewed found the integration of recency testing into routine HTS services acceptable and feasible. Among clients who completed the follow-up interview, most (92%) felt that the recency results were useful. Conclusions: Integrating recent infection testing into routine HTS services in Kenya is feasible and largely acceptable to clients and providers. More studies should be done on possible physical and social harms related to returning results, and the best uses of the recent infection data at an individual and population level.