Cost-outcome analysis of HIV testing and counseling, linkage, and defaulter tracing services in Bukoba, Tanzania

Effective services along the HIV continuum of care from HIV testing and counseling to linkage, and from linkage to antiretroviral therapy (ART) initiation and retention, are key to improved health outcomes of persons living with HIV. A comprehensive analysis of the costs and outcomes of cascade services is needed to help allocate and prioritize resources to achieve UNAIDS targets. We evaluated the costs and population-level impact of a community-wide, integrated scale-up of testing, linkage, and defaulter-tracing programs implemented in Bukoba Municipal Council, Tanzania. Costs per identified HIV-positive client for provider-initiated, and home- and venue-based testing and counseling were $92.64 United States dollars (USD), $256.33 USD, and $281.57 USD, respectively. Costs per patient linked to HIV care and ART were $47.69 USD and $74.12 USD, respectively, during all ART-eligibility periods combined. Costs per defaulter traced and returned to HIV care were $47.56 USD and $206.77 USD, respectively. The provider-initiated testing and counseling was the most cost-effective modality. Testing approaches targeted to populations groups and geographic location with high testing positivity rates may improve the overall efficiency of testing services. The expansion of ART eligibility criteria and high linkage rate also result in efficiency gains and economies of scale of linkage services.

Social network strategy (SNS) for HIV testing: a new approach for identifying individuals with undiagnosed HIV infection in Tanzania

Social network strategy (SNS) testing uses network connections to refer individuals at high risk to HIV testing services (HTS). In Tanzania, SNS testing is offered in communities and health facilities. In communities, SNS testing targets key and vulnerable populations (KVP), while in health facilities it complements index testing by reaching unelicited index contacts. Routine data were used to assess performance and trends over time in PEPFAR-supported sites between October 2021 and March 2023. Key indicators included SNS social contacts tested, and new HIV-positives individuals identified. Descriptive and statistical analysis were conducted. Univariable and multivariable analysis were applied, and variables with P-values <0.2 at univariable analysis were considered for multivariable analysis. Overall, 121,739 SNS contacts were tested, and 7731 (6.4%) previously undiagnosed individuals living with HIV were identified. Tested contacts and identified HIV-positives were mostly aged ≥15 years (>99.7%) and females (80.6% of tests, 79.4% of HIV-positives). Most SNS contacts were tested (78,363; 64.7%) and diagnosed (6376; 82.5%) in communities. SNS tests and HIV-positives grew 11.5 and 6.1-fold respectively, from October-December 2021 to January-March 2023, with majority of clients reached in communities vs. facilities (78,763 vs. 42,976). These results indicate that SNS testing is a promising HIV case-finding approach in Tanzania.

Community-wide HIV testing, linkage case management, and defaulter tracing in Bukoba, Tanzania: pre-intervention and post-intervention, population-based survey evaluation

BACKGROUND

Community randomised trials have had mixed success in implementing combination prevention strategies that diagnose 90% of people living with HIV, initiate and retain on antiretroviral therapy (ART) 90% of those diagnosed, and achieve viral load suppression in 90% of those on ART (90-90-90). The Bukoba Combination Prevention Evaluation (BCPE) aimed to achieve 90-90-90 in Bukoba Municipal Council, Tanzania, by scaling up new HIV testing, linkage, and retention interventions.

METHOD

We did population-based, cross-sectional surveys before and after our community-wide intervention in Bukoba-a mixed urban and rural council of approximately 150 000 residents located on the western shore of Lake Victoria in Tanzania. BCPE interventions were implemented in 11 government-supported health-care facilities throughout Bukoba from Oct 1, 2014, to March 31, 2017, when national ART-eligibility guidelines expanded from CD4 counts of less than 350 cells per μL (Oct 1, 2014-Dec 31, 2015) and 500 or less cells per μL (Jan 1, 2016-Sept 30, 2016) to any CD4 cell count (test and treat, Oct 1, 2016-March 31, 2017). We used pre-intervention (Nov 4, 2013-Jan 25, 2014) and post-intervention (June 21, 2017-Sept 20, 2017) population-based household surveys to assess population prevalence of undiagnosed HIV infection and ART coverage, and progress towards 90-90-90, among residents aged 18-49 years.

FINDINGS

During the 2·5-year intervention, BCPE did 133 695 HIV tests, diagnosed and linked 3918 people living with HIV to HIV care at 11 Bukoba facilities, and returned to HIV care 604 patients who had stopped care. 4795 and 5067 residents aged 18-49 years participated in pre-intervention and post-intervention surveys. HIV prevalence before and after the intervention was similar: pre-intervention 8·9% (95% CI 7·5-10·4); post-intervention 8·4% (6·9-9·9). Prevalence of undiagnosed HIV infection decreased from 4·7% to 2·0% (prevalence ratio 0·42, 95% CI 0·31-0·57), and current ART use among all people living with HIV increased from 32·2% to 70·9% (2·20, 1·82-2·66) overall, 23·0% to 62·1% among men (2·70, 1·84-3·96), and 16·7% to 64·4% among people aged 18-29 years (3·87, 2·54-5·89). Of 436 and 435 people living with HIV aged 18-49 years who participated in pre-intervention and post-intervention surveys, previous HIV diagnosis increased from 47·4% (41·3-53·4) to 76·2% (71·8-80·6), ART use among diagnosed people living with HIV increased from 68·0% (60·9-75·2) to 93·1% (90·2-96·0), and viral load suppression of those on ART increased from 88·7% (83·6-93·8) to 91·3% (88·6-94·1).

INTERPRETATION

BCPE findings suggest scaling up recommended HIV testing, linkage, and retention interventions can help reduce prevalence of undiagnosed HIV infection, increase ART use among all people living with HIV, and make substantial progress towards achieving 90-90-90 in a relatively short period. BCPE facility-based testing and linkage interventions are undergoing national scale up to help achieve 90-90-90 in Tanzania.

FUNDING

US Presidents' Emergency Plan for AIDS Relief.

Methods, outcomes, and costs of a 2.5 year comprehensive facility-and community-based HIV testing intervention in Bukoba Municipal Council, Tanzania, 2014-2017

To diagnose ≥90% HIV-infected residents (diagnostic coverage), the Bukoba Combination Prevention Evaluation (BCPE) implemented provider-initiated (PITC), home- (HBHTC), and venue-based (VBHTC) HIV testing and counseling (HTC) intervention in Bukoba Municipal Council, a mixed urban and rural lake zone community of 150,000 residents in Tanzania. This paper describes the methods, outcomes, and incremental costs of these HTC interventions. PITC was implemented in outpatient department clinics in all eight public and three faith-based health facilities. In clinics, lay counselors routinely screened and referred eligible patients for HIV testing conducted by HTC-dedicated healthcare workers. In all 14 wards, community teams offered HTC to eligible persons encountered at 31,293 home visits and at 79 male- and youth-frequented venues. HTC was recommended for persons who were not in HIV care or had not tested in the prior 90 days. BCPE conducted 133,695 HIV tests during the 2.5 year intervention (PITC: 88,813, 66%; HBHTC: 27,407, 21%; VBHTC: 17,475, 13%). Compared with other strategies, PITC conducted proportionally more tests among females (65%), and VBHTC conducted proportionally more tests among males (69%) and young-adults aged 15-24 years (42%). Of 5,550 (4.2% of all tests) HIV-positive tests, 4,143 (75%) clients were newly HIV diagnosed, including 1,583 males and 881 young adults aged 15-24 years. Of HIV tests conducted 3.7%, 1.8%, and 2.1% of PITC, HBHTC, and VBHTC clients, respectively, were newly HIV diagnosed; PITC accounted for 79% of all new diagnoses. Cost per test (per new diagnosis) was $4.55 ($123.66), $6.45 ($354.44), and $7.98 ($372.67) for PITC, HBHTC, and VBHTC, respectively. In a task-shifting analysis in which lay counselors replaced healthcare workers, estimated costs per test (per new diagnosis) would have been $3.06 ($83.15), $ 4.81 ($264.04), and $5.45 ($254.52), for PITC, HBHTC, and VBHTC, respectively. BCPE models reached different target groups, including men and young adults, two groups with consistently low coverage. Implementation of multiple models is likely necessary to achieve ≥90% diagnostic coverage.

Implementing the package of CDC and WHO recommended linkage services: Methods, outcomes, and costs of the Bukoba Tanzania Combination Prevention Evaluation peer-delivered, linkage case management program, 2014-2017

Although several studies have evaluated one or more linkage services to improve early enrollment in HIV care in Tanzania, none have evaluated the package of linkage services recommended by the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO). We describe the uptake of each component of the CDC/WHO recommended package of linkage services, and early enrollment in HIV care and antiretroviral therapy (ART) initiation among persons with HIV who participated in a peer-delivered, linkage case management (LCM) program implemented in Bukoba, Tanzania, October 2014 –May 2017. Of 4206 participants (88% newly HIV diagnosed), most received recommended services including counseling on the importance of early enrollment in care and ART (100%); escort by foot or car to an HIV care and treatment clinic (CTC) (83%); treatment navigation at a CTC (94%); telephone support and appointment reminders (77% among clients with cellphones); and counseling on HIV-status disclosure and partner/family testing (77%), and on barriers to care (69%). During three periods with different ART-eligibility thresholds [CD4<350 (Oct 2014 –Dec 2015, n = 2233), CD4≤500 (Jan 2016 –Sept 2016, n = 1221), and Test & Start (Oct 2016 –May 2017, n = 752)], 90%, 96%, and 97% of clients enrolled in HIV care, and 47%, 67%, and 86% of clients initiated ART, respectively, within three months of diagnosis. Of 463 LCM clients who participated in the last three months of the rollout of Test & Start, 91% initiated ART. Estimated per-client cost was $44 United States dollars (USD) for delivering LCM services in communities and facilities overall, and $18 USD for a facility-only model with task shifting. Well accepted by persons with HIV, peer-delivered LCM services recommended by CDC and WHO can achieve near universal early ART initiation in the Test & Start era at modest cost and should be considered for implementation in facilities and communities experiencing <90% early enrollment in ART care.