For viral load testing to prevent treatment failure, drug resistance and onward transmission, treatment programmes will need to invest in better record-keeping and clinic procedures, human resources, demand creation and decentralisation of second-line treatment provision, a large pilot study of viral load provision in southern Africa has found.
Findings from the study, funded by UNITAID, the international drug and diagnostic purchase fund and carried out in seven countries by Médecins Sans Frontières (MSF), were presented this week at the 21st International AIDS Conference (AIDS 2016) in Durban, South Africa.
Routine implementation of viral load testing in treatment programmes is essential for identifying viral load rebound and treatment failure. Early identification of viral load rebound minimises the risk of developing drug resistance, so preserves future treatment options.
Maintaining viral suppression also minimises the risk of onward transmission and the monitoring of viral suppression rates gives some idea of the potential for HIV incidence in the population. Measurement of viral load is essential at a programmatic level in order to measure facility, district and national performance in achieving the last of the 90-90-90 targets - 90% of people on treatment virally suppressed.
Until recently viral load testing was largely unavailable outside large urban hospitals or research settings in low- and middle-income countries, but recent reductions in the cost of viral load testing, coupled with World Health Organization guidance recommending the use of viral load in preference to CD4 counts as the primary laboratory monitoring test for HIV treatment, are leading to the rapid expansion of viral load testing in sub-Saharan Africa and other settings where it was once considered unsuitable for use.
PEPFAR (The US President’s Emergency Plan for AIDS Relief) has already funded rapid scale-up of viral load testing in six countries and plans to use the lessons learned to support `Test and Start` activities in other PEPFAR focus countries, using routine viral load testing. At the same time, the cost of viral load testing is falling: following negotiations between manufacturer Roche and the Diagnostic Access Initiative, the company announced a price reduction to $9.40 per test for lower- and middle-income countries.
Further price reductions are plausible: speaking at the UN 90-90-90 Target Workshop preceding the conference, Trevor Peter of the Diagnostic Access Initiative said that demand for viral load tests is forecast to rise from 5-10 million tests to at least 22 million by 2020. The 2015 price reduction enabled 1.5 million extra tests in the past year, he added.
Despite the rapid progress towards availability of viral load testing, there is still little information available on how viral load is being implemented in practice, and on what challenges implementers face as they adopt viral load testing.