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Background: Point-of-care CD4 tests at HIV diagnosis could improve linkage to care in resource-limited settings. Our objective is to evaluate the clinical and economic impact of point-of-care CD4 tests compared to laboratory-based tests in Mozambique. Methods and Findings: We use a validated model of HIV testing, linkage, and treatment (CEPAC-International) to examine two strategies of immunological staging in Mozambique: (1) laboratory-based CD4 testing (LAB-CD4) and (2) point-of-care CD4 testing (POC-CD4). Model outcomes include 5-y survival, life expectancy, lifetime costs, and incremental cost- effectiveness ratios (ICERs). Input parameters include linkage to care (LAB-CD4, 34%; POC-CD4, 61%), probability of correctly detecting antiretroviral therapy (ART) eligibility (sensitivity: LAB-CD4, 100%; POC-CD4, 90%) or ART ineligibility (specificity: LAB-CD4, 100%; POC-CD4, 85%), and test cost (LAB-CD4, US$10; POC-CD4, US$24). In sensitivity analyses, we vary POC- CD4specific parameters, as well as cohort and setting parameters to reflect a range of scenarios in sub-Saharan Africa. We consider ICERs less than three times the per capita gross domestic product in Mozambique (US$570) to be cost-effective, and ICERs less than one times the per capita gross domestic product in Mozambique to be very cost-effective. Projected 5-y survival in HIV-infected persons with LAB-CD4 is 60.9% (95% CI, 60.9%-61.0%), increasing to 65.0% (95% CI, 64.9%-65.1%) with POC-CD4. Discounted life expectancy and per person lifetime costs with LAB-CD4 are 9.6 y (95% CI, 9.6-9.6 y) and US$2,440 (95% CI, US$2,440-US$2,450) and increase with POC-CD4 to 10.3 y (95% CI, 10.3-10.3 y) and US$2,800 (95% CI, US$2,790-US$2,800); the ICER of POC-CD4 compared to LAB-CD4 is US$500/year of life saved (YLS) (95% CI, US$480US$520/YLS). POC-CD4 improves clinical outcomes and remains near the very cost-effective threshold in sensitivity analyses, even if point-of-care CD4 tests have lower sensitivity/specificity and higher cost than published values. In other resource-limited settings with fewer opportunities to access care, POC-CD4 has a greater impact on clinical outcomes and remains cost-effective compared to LAB-CD4. Limitations of the analysis include the uncertainty around input parameters, which is examined in sensitivity analyses. The potential added benefits due to decreased transmission are excluded; their inclusion would likely further increase the value of POC-CD4 compared to LAB-CD4. Conclusions: POC-CD4 at the time of HIV diagnosis could improve survival and be cost-effective compared to LAB-CD4 in Mozambique, if it improves linkage to care. POC-CD4 could have the greatest impact on mortality in settings where resources for HIV testing and linkage are most limited. Please see later in the article for the Editors' Summary., Introduction In sub-Saharan Africa, over 50% of HIV-infected patients remain unlinked to clinical care, despite the dramatic scale-up of HIV treatment over the past decade [1]. Point-of-care technologies have been [...]

The objective of this study was to quantify the impact of a new technology to communicate the results of an infant HIV diagnostic test on test turnaround time and to quantify the association between late delivery of test results and patient loss to follow-up. We used data collected during a pilot implementation of Global Package Radio Service (GPRS) printers for communicating results in the early infant diagnosis program in Mozambique from 2008 through 2010. Our dataset comprised 1757 patient records, of which 767 were from before implementation and 990 from after implementation of expedited results delivery system. We used multivariate logistic regression model to determine the association between late result delivery (more than 30 days between sample collection and result delivery to the health facility) and the probability of result collection by the infant's caregiver. We used a sample selection model to determine the association between late result delivery to the facility and further delay in collection of results by the caregiver. The mean test turnaround time reduced from 68.13 to 41.05 days post-expedited results delivery system. Caregivers collected only 665 (37.8%) of the 1757 results. After controlling for confounders, the late delivery of results was associated with a reduction of approximately 18% (0.44 vs. 0.36; P < 0.01) in the probability of results collected by the caregivers (odds ratio = 0.67, P < 0.05). Late delivery of results was also associated with a further average increase in 20.91 days of delay in collection of results (P < 0.01). Early infant diagnosis program managers should further evaluate the cost-effectiveness of operational interventions (eg, GPRS printers) that reduce delays.

Objective: To evaluate the accuracy of a point-of-care (POC) nucleic acid-based test (NAT) for early infant HIV diagnosis (EID) in primary health clinics in Mozambique., Methods: POC and laboratory NAT EID tests were conducted on matched blood samples collected from 827 HIV-exposed infants younger than 18 months who were enrolled consecutively at 4 periurban primary health clinics and the central hospital in Maputo. Lancet heel draw blood collected by nurses was tested on site for HIV-1/-2 RNA on the Alere HIV NAT POC device and also used to create dried blood spots for later laboratory EID testing on the Roche Cobas Taqman/Ampliprep instrument. Results were used to determine the sensitivity, specificity, and agreement between the POC and laboratory NAT EID tests., Results: The sensitivity and specificity of POC NAT EID testing were 98·5% (95% confidence interval (CI): 91.7 to 99.9, n = 65) and 99·9% (95% CI: 99.3 to 100, n = 762), respectively, compared with laboratory EID tests. Overall agreement was high (Cohen kappa = 0·981; 95% CI: 0.96 to 1.00). Positive (98·5%; 95% CI: 96·3 to 100) and negative 99.9% (95% CI: 99.7 to 100) test agreement was also high., Conclusions: Primary health care nurses accurately performed POC NAT EID testing within primary health care clinics. On-site nucleic acid-based EID testing is technically feasible in clinic settings and could be used in efforts to improve access to pediatric HIV antiretroviral treatment.

Point-of-care (POC) CD4 testing was implemented at a stand-alone HIV voluntary testing and counseling centre in Harare, Zimbabwe. To validate the use of this new technology, paired blood samples were collected from 165 patients either by a nurse or a laboratory technician and tested using POC and conventional laboratory CD4 machines. Finger prick (capillary) blood was collected directly into the PIMA POC CD4 Analyzer cartridges and tested immediately, whereas venous blood collected into evacuated tubes was used for CD4 enumeration on a Becton Dickinson FACSCalibur. There was no significant difference in mean absolute CD4 counts between the POC PIMA and Becton Dickinson FACSCalibur platforms (+7.6 cells/microL; P = 0.72). Additionally, there was no significant difference in CD4 counts between the platforms when run by either a nurse (+18.0 cells/microL; P = 0.49), or a laboratory technicians (-3.1 cells/microL; P = 0.93). This study demonstrates that POC CD4 testing can be conducted in a voluntary testing and counseling setting for staging HIV-positive clients. Both nurses and laboratory technicians performed the test accurately, thereby increasing the human resources available for POC CD4 testing. By producing same-day results, POC CD4 facilitates immediate decision-making, patient management and referral and may help improve patient care and retention. POC CD4 may also alleviate testing burdens at traditional central CD4 laboratories, hence improving test access in both rural and urban environments.