ATLANTA, Ga – By the time the vast majority of people who have HIV reach testing and treatment for the virus, they have had it long enough, Greg Greene of the U.S. Centers for Disease Control and Prevention said here today, that they are vulnerable to deadly fungal infections.
One, cryptococcal meningitis, causes 11 percent of HIV-related deaths globally, alone, he said. In sub- Saharan Africa where 500,000 cases occur annually, the toll is much higher, and in South Africa, the fungal infection causes 29 percent of HIV-related deaths. And even with efforts to meet UNAIDS targets of diagnosing 90 percent of all people with HIV, ensuring treatment access to 90 percent of them, and ensuring that treatment is effective in suppressing the virus in 90 percent of them, without the use of existing tools against the fungal infection, it will continue to take an unnecessary toll, he said.
Tools to control the toll of the infection include an inexpensive point-of-care cryptococcal meningitis diagnostic test and World Health Organization guidelines to screen for the infection in all individuals with a CD4, or immune cell, count less that 100 per milliliter of blood. Both are important because early intervention can be life-saving. The antigen for cryptococcal meningitis is detectable in the blood three weeks prior to the development of meningitis and the antifungal drug fluconazole can prevent the infection from disseminating throughout the body.
Research trials conducted in Zambia have demonstrated that screening and prompt treatment reduce the risk of death, while cost-effectiveness studies in South Africa have shown the intervention is cost effective even in regions with a low burden of disease, Greene said. South Africa is one of the first countries to implement the so called “reflex screening” strategy where when a CD4 test shows a count is below 100, the cryptococcal antigen test is automatically performed in the laboratory at the same time.
Médecins Sans Frontières is piloting an effort to take screening to areas with less infrastructure by training lay counselors to administer the screening test, Greene said, with encouraging first results showing 86 percent of patients returning for care and treatment.
Greene spoke at a session that also highlighted another fungal infection, histoplasmosis, as a threat to persons living with HIV in Central and South America. In that region an estimated 9,600 people a year die from that disease, which is frequently mistaken for tuberculosis, according to an analysis presentated at the session by Dr. Antoine Adenis from French Guyana.
This death toll, according to Adenis, is equivalent to tuberculosis as an HIV-related cause of death in half of the countries in Central and South America. He called histoplasmosis a “neglected killer” because of poor lab capacity, the failure of clinicians to diagnose the infection, and the absence of a point-of-care test. Adenis called on country leaders to modify their HIV strategic plans to make visible and address histoplasmosis.
“We need to work on advocacy, and we need numbers to do that,” he said.