Higher HIV viral loads are linked to a faster depletion of CD4 cells among South Africans not taking antiretrovirals (ARVs), aidsmap reports. Publishing their findings in PLOS ONE, researchers studied 1,106 people with subtype C of HIV whose CD4s were above 200 and who were treatment naive at the outset and who had positive tuberculosis skin tests. (The participants had been recruited to a study testing a preventive TB treatment.)

With recruitment starting in 2003, the investigators followed the participants for a median 44 months, regularly monitoring their CD4s and viral loads. The participants had a median CD4 count of 490 and a median viral load of 16,050 upon starting the study.

The average CD4 drop was 38.4 cells per year, which is a less steep decline than is typically found among those with subtype B of HIV, the most common in the United States. Those whose viral loads were above 10,000 had an average annual decline of 11 percent, compared with 14 percent for those with viral loads above 100,000.

Twenty-two percent of the participants had a baseline viral load above 100,000, which put them at high risk of transmitting the virus; yet they were still ineligible to receive ARVs under current South African guidelines. The study suggested that a significant proportion of people in South Africa may thus spend a good deal of time living with highly infectious virus before receiving the benefits of treatment as prevention (TasP), considering that ARVs greatly reduce their likelihood of passing on the virus.

To read the aidsmap story, click here.

To read the study, click here.