Abstract
There is growing demand within the global health community to find ways to simplify and improve the efficiency of diagnostics for HIV/AIDS without diminishing the quality of patient care. At the same time, there is a need to significantly increase the level of access to robust, high-quality diagnostics in resource-limited settings in order to facilitate early detection and treatment of HIV/AIDS.
Of the various tests required for initial diagnosis, staging, and ongoing monitoring of HIV, those that present the most persistent challenges to improved access and efficiency are CD4, viral load, and early infant diagnosis(EID). This report reviews both current diagnostic platforms and pipeline technologies for these three key tests.For each, the great majority of testing options available today are laboratory-based platforms performed on sophisticated instrumentation requiring dedicated laboratory space and trained laboratory technicians. In many cases, laboratory-based testing is expensive; in almost all cases, it requires sample transport networks to enable access for patients in peri-urban and rural settings.
Given the limitations of laboratory-based testing, it is generally accepted that in order to improve access to, and reduce the cost of, CD4, viral load, and EID testing in resource-limited settings, such testing needs to be brought closer to the point of patient care. This report therefore examines the new diagnostic technologies inthe pipeline—most of which are designed for use at or near the point of patient care—and considers to what degree they meet the World Health Organization’s (WHO’s) “ASSURED” criteria, meaning that they are (or will be): Affordable, Sensitive, Specific, User-friendly, Robust/Rapid, Equipment-free, and Deliverable to those who need the test.
With respect to CD4 testing, which is used for staging and monitoring HIV patients prior to initiation onto antiretroviral therapy (ART), the general conclusion is that currently there are a number of good laboratory-based platforms using proven flow cytometry technology. These tests can be efficient and cost-effective when performed by well-trained laboratory technicians and when combined with good sample transport systems.However, in order to improve access, especially for rural patients, and to reduce patient loss to follow-up, there remains a need for high-quality, cost-effective point of care (POC) CD4 testing options. Three such options are already on the market, and several others are under development with anticipated release over the coming two years. At least one of these will be a disposable POC CD4 test. Assuming that the performance of these POC tests stands up to robust evaluation, the pipeline presents real promise.
