Innovative way to target HIV infections
A KWAZULU-NATAL research institute has developed a new method to predict where the highest rate of new HIV infections will likely occur, allowing for targeted treatment and interventions.
Using cutting-edge data analytical methods, Africa Health Research Institute (AHRI) scientists show that population viral load measures, which have previously been used to try to predict the intensity of new HIV infections in a particular area, do not accurately predict HIV incidence in a rural South African setting.
The researchers were led by AHRI faculty scientist Professor Frank Tanser, who is also the UKZN Professor of Epidemiology and Honorary Professor at University College London.
“As countries gear up to meet the UNAids 90-90-90 HIV treatment targets, accurately measuring progress and providing evidence of the impact of widespread treatment on life expectancy as well as the rate of new HIV infections is critical,” he said.
One of the accepted ways of doing this is using this measurement. HIV viral load level – or the amount of virus present in a person’s semen or blood – is the single most important biological factor when it comes to HIV transmission.
This means the higher a person’s viral load, the more infectious they are.
Based on this, calculating an average viral load for every HIV infected person living in a community over a given period could predict the potential for transmission and thus the future rate of new HIV infections.
In this AHRI study in partnership with the University of KwaZulu-Natal and University College London, 8 732 research participants living in the programme area between 2011 and 2015 were involved.
The researchers found that many of the methods currently used do not accurately predict HIV incidence in a particular community. Once they adjusted the metrics to take into account spatial variations in viral load patterns as well as proportion of HIV infections within a community, the measures became highly predictive.
The authors have also cautioned against using routine health facility-based viral load data only to predict the transmission potential of similar rural settings, as they found this data doesn’t give an accurate prediction of rate of new HIV infections.
They also found high viral loads were 40% more prevalent in men compared with women. Tanser said this reflects observations throughout Africa showing that men are less likely to be tested for HIV and successfully link to HIV care, as well as being less likely to successfully adhere to treatment.
“In this era of decreasing HIV funding, it’s critical that we make the best use of the resources available.
“One way we can do this is to target areas of high transmission.
“Using these indices we can now identify vulnerable communities where future rates of new HIV infections will be highest – which will be useful in guiding prevention intervention strategies.
“One of the reasons that the rate of new infections is so high among women is because their male partners have high viral loads as a consequence of them not accessing HIV care and treatment.
“At AHRI we are looking at innovative solutions including financial incentives for men to test and treat, as well as gender sensitive mobile and technology options,” said Tanser.