Validation, performance under field conditions, and cost-effectiveness of Capillus HIV-1/HIV-2 and determine HIV-1/2 rapid human immunodeficiency virus antibody assays using sequential and parallel testing algorithms in Tanzania.

Rapid human immunodeficiency virus (HIV) antibody tests support the effort to expand access to HIV testing and counseling services in remote, rural, and poor parts of the world. We validated the Capillus HIV-1/HIV-2 (Trinity Biotech PLC, Bray, County Wicklow, Ireland) and Determine HIV-1/2 (Abbott Laboratories, Abbott Park, IL) rapid tests in a reference laboratory using patient samples from Tanzania and evaluated the performance of the tests under field conditions in northern Tanzania. We used the resulting data to study sequential and parallel testing algorithms. In the validation study, sensitivity, specificity, the predictive value of a positive test (PV(+)), and the predictive value of a negative test (PV(-)) were all 100% for Capillus and Determine. In the field evaluation among 12,737 clients, sensitivity, specificity, PV(+), and PV(-) were 99.7%, 99.8%, 98.7%, and 99.9%, respectively, for Capillus and 99.6%, 99.9%, 99.5%, and 99.9%, respectively, for Determine. A sequential testing algorithm that did not confirm a negative initial Capillus result with a Determine result cost $7.77 per HIV diagnosis but missed 0.3% of HIV infections. A sequential testing algorithm that did not confirm a negative initial Determine result with a Capillus result cost $7.64 per HIV diagnosis but missed 0.4% of HIV infections. A parallel testing algorithm cost $13.46 per HIV diagnosis but detected more HIV-infected clients.

Predictors of incomplete adherence, virologic failure, and antiviral drug resistance among HIV-infected adults receiving antiretroviral therapy in Tanzania.

BACKGROUND: Access to antiretroviral therapy is rapidly expanding in sub-Saharan Africa. Identifying the predictors of incomplete adherence, virologic failure, and antiviral drug resistance is essential to achieving long-term success. METHODS: A total of 150 subjects who had received antiretroviral therapy for at least 6 months completed a structured questionnaire and adherence assessment, and plasma human immunodeficiency virus (HIV) RNA levels were measured. Virologic failure was defined as an HIV RNA level >400 copies/mL; for patients with an HIV RNA level >1000 copies/mL, genotypic antiviral drug resistance testing was performed. Predictors were analyzed using bivariable and multivariable logistic regression models. RESULTS: A total of 23 (16%) of 150 subjects reported incomplete adherence. Sacrificing health care for other necessities (adjusted odds ratio [AOR], 19.8; P<.01) and the proportion of months receiving self-funded treatment (AOR, 23.5; P=.04) were associated with incomplete adherence. Virologic failure was identified in 48 (32%) of 150 subjects and was associated with incomplete adherence (AOR, 3.6; P=.03) and the proportion of months receiving self-funded antiretroviral therapy (AOR, 13.0; P=.02). Disclosure of HIV infection status to family members or others was protective against virologic failure (AOR, 0.10; P=.04). CONCLUSIONS: Self-funded treatment was associated with incomplete adherence and virologic failure, and disclosure of HIV infection status was protective against virologic failure. Efforts to provide free antiretroviral therapy and to promote social coping may enhance adherence and reduce rates of virologic failure.

Capacity of health-care facilities to deliver HIV treatment and care services, Northern Tanzania, 2004.

Few data exist on the current capacity of Tanzanian health-care facilities to deliver antiretroviral therapy (ART). We evaluated this capacity among Northern Zone facilities in 2004 using a questionnaire that addressed human resources, clinical facilities and services, and laboratory capacity. Of 19 facilities surveyed, nine (47%) had staff trained to manage ART and three (16%) prescribed ART. Two (11%) offered CD4 counts, five (26%) offered liver function tests, 16 (84%) offered chest radiography, and 18 (95%) offered acid-fast sputum staining. Of 12 (67%) facilities offering outpatient HIV/AIDS services, 12 (100%) provided co-trimoxazole to outpatients and six (50%) provided isoniazid (INH). All 19 (100%) facilities offered rapid HIV tests and full blood pictures. Overall in 2004, facilities needed strengthening to increase staff training in ART management and to implement INH for treatment of latent tuberculosis. Laboratory facilities for ART monitoring were inadequate, and outpatient ART was limited.

Cost-effectiveness of free HIV voluntary counseling and testing through a community-based AIDS service organization in Northern Tanzania.

OBJECTIVES: We evaluated the cost-effectiveness of fee-based and free testing strategies at an HIV voluntary counseling and testing (VCT) program integrated into a community-based AIDS service organization in Moshi, Tanzania. METHODS: We waived the usual fee schedule during a 2-week free, advertised VCT campaign; analyzed the number of clients testing per day during prefree, free, and postfree testing periods; and estimated the cost-effectiveness of limited and sustained free testing strategies. RESULTS: The number of clients testing per day increased from 4.1 during the prefree testing interval to 15.0 during the free testing campaign (P<.0001) and remained significantly increased at 7.1 (P<.0001) after resumption of the standard fees. HIV seroprevalence (16.7%) and risk behaviors were unchanged over these intervals. Modeled over 1 year, the costs per infection averted with the standard fee schedule, with a 2-week free VCT campaign, and with sustained free VCT year-round were $170, $105, and $92, respectively, and the costs per disability-adjusted life year gained were $8.72, $5.40, and $4.72, respectively. CONCLUSIONS: The provision of free VCT enhances both the number of clients testing per day and its cost-effectiveness in resource-limited settings.