New Low-Cost Technologies Offer Practical Solutions for Developing World
CDC Research Indicates New CD4 and Viral Load Tests Could Dramatically Improve Management of Disease in Africa
Several African Studies Illustrate Innovative Solutions to Prevention Challenges
BARCELONA, Spain - New study data from several African countries reveal progress in identifying practical solutions for improving HIV testing, prevention and treatment in highly affected countries. The study results, summarized today at a press briefing convened by the Centers for Disease Control and Prevention (CDC) at the XIV International AIDS Conference, highlight significant advances that allow for disease monitoring at much lower costs than currently available. These include a new method of monitoring CD4+ cell levels in blood at one-fourth the cost of current CD4+ tests, and a new technology for monitoring viral load at one-fifth the cost of existing tests. In addition, other CDC studies highlight innovative strategies some African governments are using to successfully increase HIV testing in their countries.
"These study results point to realistic solutions for today's challenges in fighting HIV in Africa," said Harold Jaffe, M.D., acting director of CDC's HIV, STD, and TB prevention programs. "Making progress against HIV infection and AIDS in these highly affected countries requires simpler, affordable treatment and prevention strategies that work in real-world settings."
Low-Cost Technologies Prove Effective for Use in Developing Countries
CDC researchers in Uganda, working in collaboration with the Ugandan Ministry of Public Health, found that the significantly cheaper CD4+ test and viral load monitoring technology performed effectively, comparable to standard tests in use today.
New CD4+ test is effective at one-fourth the cost of existing tests. Researchers in Uganda, led by Wilja Mandy, found that a new technology for measuring CD4+ cell levels in blood performed comparably to the standard technology used today - a finding that could have broad implications for HIV disease management in developing countries because of the new test's dramatically lower price. The new technology, known as panleucogating (PLG), looks for CD4+ markers on white blood cells. Researchers compared PLG results with those obtained using standard CD4+ monitoring (FACSCount), as well as with another alternative approach known as lymphocyte gating. Because blood samples from remote clinics must often travel for days to reach a central laboratory, researchers also compared the three monitoring processes using three-day-old, stabilized blood samples.
With fresh blood samples, PLG obtained results that correlated closely with FACSCount, while superior results were obtained when analyzing stabilized blood. Lymphocyte gating showed much poorer results in both fresh and stabilized blood analysis. The potential cost of the PLG test is less than US$5.00 per test, compared with the current market cost of US$20.00 for the standard CD4+ test. The PLG test is used routinely in South Africa, and the World Health Organization has provisionally accepted it as an alternative for affordable CD4+ testing in resource-poor settings. Abstract MoPeB3104, "Less expensive CD4+ T cell monitoring using panleucogating," Poster, Monday, 8 July 2002, 8:00 (2:00 AM EDT)
At one-fifth the cost, new viral load test rivals standard test in monitoring HAART. A new test for measuring viral load, costing one-fifth the price of existing technology, showed significant promise for effectively monitoring HIV treatment in developing countries, according to research by CDC's Robert Downing, Ph.D., and colleagues in Uganda. The test measures the blood's level of reverse transcriptase, an enzyme unique to retroviruses that correlates with the amount of HIV present in the blood. Results from the test, known as reverse transcriptase viral load assay (RT-VLA), were compared against those obtained using an RNA viral load test, the international standard test for monitoring viral load in HIV-infected patients. The technology, which costs US$30.00 (compared to US$150 for the standard viral load test), performed as well as the RNA test in measuring trends in viral load over time for patients on highly active antiretroviral therapy (HAART). Measurements of viral load provide valuable information on treatment efficacy in these patients and are used to guide treatment decisions. While the RT-VLA proved effective in measuring trends in viral load for most patients, it did not detect virus for two of 13 specimens in which the RNA test reported a high RNA viral load (between 10,000 and 100,000 copies per milliliter). The study authors stress that the implications of this and other variations are unclear, and further comparisons of the tests in patients receiving HAART are required to resolve these differences. Abstract MoPeB3105, "Evaluating the Cavidi reverse transcriptase assay to monitor response to anti-retroviral therapy," Poster, Monday, 8 July 2002, 8:00 (2:00 AM EDT)
African Countries Implement Innovative HIV Testing Programs
A number of countries across Africa are successfully increasing the number of people with access to HIV testing using a variety of innovative strategies, according to CDC studies discussed today. Research showed that techniques from social marketing campaigns to community-based testing have helped some countries to significantly increase HIV testing.
"This research shows that effective, creative responses are working even in countries with very limited resources," Eugene McCray, M.D., director of CDC's global AIDS programs, stated at today's press conference where he highlighted several African programs. "Such innovative strategies are essential to combating HIV in Africa."
Botswana. In a new effort to address the country's high HIV prevalence and shortage of voluntary testing services, CDC and the government of Botswana have partnered to stage a broad campaign to increase the proportion of people in Botswana who know their HIV status. The effort includes a new network of voluntary counseling and testing centers called "Tebelopele" ("looking into the future"), and a social marketing campaign with radio promotions, billboards, and print advertisements. In addition to the campaign, one of the country's most popular radio series now includes an HIV sub-plot that encourages HIV counseling and testing. High-level government leaders have helped promote the campaign by getting tested and helping unveil new testing centers. The number of persons undergoing voluntary counseling and testing have since increased by more than 250 percent, from 3,782 clients served in 2000 to 13,729 in 2001. Abstract MoPeF3994, "Social marketing: a strategy for creating acceptability and increasing utilization of voluntary HIV counseling and testing services in Botswana," Oral Presentation, Monday, 8 July 2002, 14:00 (8:00 AM EDT); Abstract MoPeG4283, "Involving political leadership to establish and enhance acceptance of voluntary HIV counseling and testing (VCT) networks, Botswana," Poster, Monday, 8 July 2002, 8:00 (2:00 AM EDT)
Kenya. By moving HIV testing into the community, a pilot program in the Nairobi area of Kibera has greatly increased utilization of voluntary testing and counseling, which has traditionally been offered in a limited range of clinical settings. Since March 2001, counselors have offered pre- and post-test counseling and rapid, whole blood HIV tests in non-traditional sites including churches, a youth center, and a chief's compound. Clients receive confirmed test results within 20 minutes, and are shown their own test strips, which increases their confidence in the reliability of results. All clients receive prevention counseling, as well as follow-up care and support for those who are HIV positive. Use of the program has increased rapidly, from 76 clients in March to more than 1,000 per month from July to December. Abstract MoOrF1077, "Rapid increase in utilization of voluntary counseling and testing through a community-based model in Kibera slum, Nairobi, Kenya," Oral Presentation, Monday, 8 July 2002, 14:00 (8:00 AM EDT).