It’s the best way to ensure antiretroviral treatment is working for those getting it, protecting their immune systems and preventing illness and transmission — and the alternative is more costly. Yet a World Health Organization published study of how frequently antiretroviral treatment programs in seven countries across the Americas check their patients’ viral loads and immune cell counts found many were doing those checks less often than recommended.
The study looked at data collected from 2000 to 2011 from programs in Haiti, where HIV prevalence is the highest in the region and Honduras, which also has an epidemic that affects the general population, as well as Argentina, Brazil, Chile, Mexico and Peru, where the impact of HIV is considered concentrated among men who have sex with men and people who inject drugs.
Guidelines in the region recommend checking immune cell, or CD4, counts and viral loads every two to six months for people starting treatment, and every three to six months once their virus levels are suppressed. In the meantime, WHO has updated guidelines to emphasize the importance of viral load testing.
Across the programs, researchers found that immune cell counts and viral load testing was carried out at least every six months, on average, for just 62 percent of those in care for whom data was collected. During the time studied, the site in Haiti did not monitor viral loads at all. Monitoring of CD4 counts ranged from an average of 2.6 times a year in Argentina and Mexico to once a year in Haiti. Monitoring of viral loads ranged from about 2.6 times a year in Argentina and Mexico to less than once a year in Honduras. Across the sites, older patients and those who had started antiretroviral treatment more recently were checked more often.
Researchers also found the cost of monitoring per patient varied greatly between countries, with the yearly cost of CD4 count monitoring in Mexico per patient about four times the median cost of the region and nearly nine times the cost in Honduras. Researchers also say, however that the range was likely due to a range of factors related to patients, care providers, and structural issues affecting service provision and access, that they recommend be studied further. They also conjecture that viral load testing in Haiti, where emergency responses to a series of natural disasters has diverted resources from HIV-related care efforts, would increase if the Global Fund to Fight AIDS, Tuberculosis and Malaria updates its policy on funding treatment monitoring.