For some, a portion of $3 billion per year would seem to be all that's required to eradicate the pandemic killing millions of Africans each year. To others, such a notion is folly. Regardless of how one views the funding, there is one thing all sides can agree on: that all the monies be focused on promoting the greatest benefit for the greatest number. But how to achieve this? A clinical laboratorian who works with resource poor nations believes that the success of this major new effort to combat HIV/AIDS must include one thing: the use of laboratory testing as both a lynchpin of the program, and a tool to measure success.
Deshratn Asthana, Ph.D., MBA, HCLD, Associate Professor of Medicine and Psychiatry, and Director of the Laboratory for Clinical and Biological Studies at University of Miami School of Medicine, Miami, FL, will discuss his recommendations during his presentation, "HIV Diagnostics and Monitoring Technologies for Resource-Poor Settings," being offered in conjunction with the 55th Annual Meeting of the American Association of Clinical Chemistry (AACC), July 20-24, 2003 at the Pennsylvania Convention Center, Philadelphia, PA. More than 16,000 attendees are expected.
Background
In the United States and other developed countries, two tests are used as primary outcome measurements for assessing the management of HIV-infected persons. The "HIV-1 RNA Viral Load Test" measures the amount of HIV-1 RNA in circulation within the body and is generally used by physicians to monitor patients who are reporting as ill. The "CD4 Cell Count" test is generally used to monitor immune status of patients. It is an important test since the HIV virus targets and destroys the CD4 cells; patients with low numbers of CD4 cells are sicker, paving the way for opportunistic infections that will affect patient outcome. CD4 cell test results also help indicate how a patient is responding to medications/therapy.
Less than four percent of the infections are in the United States and Western Europe. The majority of infections are in resource-poor countries, such as Africa, Southeast Asia and Russia. In these countries, the cost of diagnostic and monitoring technologies for patient management is of great concern. While the cost of medications has been addressed through the active involvement of the International AIDS Society, the World Health Organization's (WHO) and consent of the manufacturers of generic medications however; the problem of costs for diagnosing and monitoring patients has yet to be addressed.
The cost of diagnostic testing is significantly out of reach for those who are affected most. Viral load and CD4 cells tests are currently priced at between $100-$150 each, compared with approximately $300 for a month's supply of generic brand medication (down from $12,000 - $18,000 annually in the USA). Moreover, multiple tests are required, since patients must be tested at least quarterly to assess their response to the treatment, among other reasons.
Alternative Testing Methods
There are two ways to address the issue. One is for manufacturing companies to subsidize the cost of the tests on a country-by-country basis. Another way is to develop alternate technologies that give an approximate answer. Accordingly, there has been significant interest in alternative testing methods. Not simply because of pricing considerations, but also because of in-country conditions, such as a ready supply of electricity, availability of qualified technicians to perform the tests, maintaining quality assurance programs, and the number of qualified labs in the country to perform the tests.
Some countries are using the heat-denatured p24 antigen test, a test that was originally used in the US and Western Europe before it improved and ultimately surpassed by the viral load and CD4 assays. This test used as a viral marker and provides an indication of the amount of virus in the patient, albeit not specific viral copies. The cost of this test is approximately $10.00 per test. Another test known as the Quantitative RT-VLA. This test measures the reverse transcriptase (RT) activity in plasma samples from HIV-infected patients. The approximate cost is $20.00 per test.
Alternatives to flow cytometric quantitation of CD4 T-cells are Cyto-Spheres, Dynabeads, and PanLeucogated CD4 T-cell enumeration, which are being used in a number of countries. These assays involve the physical counting of cells and approximate cost of reagents varies $4.00 to $16.00 per test.
All of these tests allow the physician to make decisions about the patient's clinical status. While such tests may not provide the exact number of copies of the virus in a patient, they do provide the physician and patient an indication of whether treatment should be initiated or modified.
Conclusions
According to Dr. Asthana, the best way to assist those infected with HIV/AIDS in resource-poor countries, besides providing medications, is to properly diagnose and monitor patients using affordable alternative testing methods. In addition, general introduction of antiretroviral therapy in resource-poor countries have implications for the development of HIV drug resistance and which will require further investigations and resources. Without proper testing, Dr. Asthana predicts that public health officials will never really know how far-reaching and effective their best efforts really are.
The American Association for Clinical Chemistry (AACC) is the world's most prestigious professional association for clinical laboratorians, clinical and molecular pathologists, and others in related fields. AACC's members are specialists trained in the areas of laboratory testing, including genetic disorders, infectious diseases, tumor markers and DNA. Their primary professional commitment is utilizing tests to detect, treat and monitor disease.
Editor's Note: To schedule an interview with Dr. Asthana, please contact Donna Krupa at 703-527-7357 (direct dial), 703-967-2751 (cell) or djkrupa1@aol.com. Or contact the AACC Newsroom at: 215-418-2429 between 8:00 AM and 4:00 PM EST July 20-24, 2003.
AACC NEWSROOM OPEN
July 20-July 24, 2003
Pennsylvania Convention Center
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Telephone: 215-418-2429