New test could cut costs in developing world

A new scientific breakthrough promises to make treatment more affordable in developing countries.

A South African doctor has discovered a cheaper and more accurate method of CD4 testing, which cuts the cost of CD4 tests by almost a third. "With the new test, state hospitals can monitor three times as many patients," Dr Debbie Glencross of South Africa's National Health Laboratory Service (NHLS), told PlusNews on Monday.

According to Glencross, the haemotologist who discovered the new method, the new test is much quicker and easier to use. "The conception was that because it is so simple, the quality would be poorer, but it is actually of a much better quality," she said.

The new technique, called PanLeucogate CD4 T cell enumeration, measures all white blood cells - not just certain types - and then works out the number of CD4 cells in each millionth of a litre of blood. "It was a shot in the dark, but it really worked," she said.

CD4 cell testing is used to determine the efficacy of antiretroviral therapy (ART). By keeping track of the number of CD4 cells in the bloodstream, doctors can tell how far HIV infection has progressed. The prohibitive cost of the test has prevented it from being conducted in most public hospitals.

The NHLS has patented the technique to prevent multinational and private companies from selling the tests at an exorbitant price. "The patent was a protection because we wanted it to get to the people who needed it most," Glencross added.

Earlier this year, African physicians attending a meeting on "monitoring and diagnostic tools for the management of antiretroviral therapy in resource-poor settings", called for faster and cheaper HIV/AIDS monitoring techniques, as most tests used for managing the virus were out of their reach.

According to a report in the American Foundation for AIDS Research (AMFAR) Treatment newsletter, the cheapest equipment for measuring CD4 counts cost US $75,000 to US $100,000, and added to this expense is money needed to train and hire technical staff, maintain and repair broken equipment and ship and store samples, the report said.

Existing guidelines for managing patients on antiretroviral therapy (ART) use viral load and CD4 count testing to measure the impact of ART on the patient's health.

The response to the new technique had been "unbelievable", Glencross said. The United States' Centre for Disease Prevention has expressed an interest in collaborating in a study. The World Health Organisation has also invited Glencross to be part of a working group on monitoring ART in resource poor settings.

Despite the interest shown, implementing the technique in developing countries was still "slow to get going", she said.

The overwhelming positive response from laymen, however, showed how people were "starved for information and new hope", Glencross said. "As scientists, we just thought it was one small contribution for the HIV/AIDS struggle," she added.