Winning the battle against HIV and other infectious diseases is always a matter of how well diagnostics and treatment are adapted to local conditions. Particularly in low resource settings, the requirements of a prompt, efficient and reliable disease management are challenging. Since centralized diagnostic machines are cost-intensive and require considerable bench space, air conditioning and trained personnel, professional diagnostic assays are often tied to large city laboratories although most patients live outside the cities.
Accordingly, too few people living with HIV can be accessed and patients could get lost or urgent treatment decisions delayed because of long turnaround times for results. As there are many processes involved between sample collection, transportation, testing and return of the results, the chance of error with centralised testing is increased.
The real world needs decentralized testing at the point of care (POC), where the patients are seen and where prompt clinical intervention can be initiated – a system perfectly capable in even the most challenging and resource-limited conditions.
‘Proven in the field’ – the decentralisation of viral load testing has impacted positively on HIV management. Previously, with the centralised system, the number of people living with HIV who accessed viral load testing stood at 15 percent. Until today it has gone up to 70 percent, performed by nucleic acid-based molecular diagnostic assays which have become the standard of POC.
With rapid POC molecular assays currently in clinical use in Zimbabwe, Malawi, Uganda and Central African Republic, DRW has successfully established the SAMBA platform (Simple AMplification Based Assay) as a true ‘game changer’ in HIV management for acute infection and early infant diagnosis as well as antiretroviral therapy monitoring.
SAMBA is delivered through two innovative platforms offering qualitative or semi-quantitative detection of HIV-1 RNA and DNA across multiple subtypes: SAMBA I and SAMBA II. Both platforms represent a new generation of near patient and rapid POC testing enabling ‘test and treat’ capability in resource constrained areas where reliable, prompt diagnosis and monitoring would otherwise be unavailable.
Thanks to rapid turnaround-times of less than two hours, unlike in the past when results would take weeks or months, the use of this new technology can help improve treatment outcomes, survival of individuals and prevention of HIV transmission itself.
Gary Brook, Clinical Lead Sexual Health Services, North West London NHS Trust
Thanks to rapid POC molecular assays accurate testing, prompt prognosis and just-in-time response to ART have become reality. As such DRW's technology has been internationally recognized with numerous Technology Awards over the years. In 2016 the SAMBA platform received the European Patent Office Award for inventiveness applauded by clinicians for being simple to use, accurate, robust, reliable, stable and with performance characteristics similar to those of centralized PCR-based assays.
Consequently, the SAMBA technology has helped hospitals accelerate Prevention of Mother to Child Transmission (PMTCT) of HIV programmes, where fast results would help reduce transmission of the virus to the unborn baby. It also has helped keep most patients on first line treatment rather than switch them to second line treatment thanks to adequate assessment and enhanced monitoring of drug efficacy. Loss to follow up cases where patients don’t come back for their results have also been reduced.
It will remain a unique aspect of future DRW efforts to serve and service the people in real need by bringing new innovative diagnostics to the world. Assays in development for the SAMBA platform include tests for hepatitis B and C, influenza A and B, as well as a duplex test for chlamydia and gonorrhoea. And more will follow.
The SAMBA II machines will help the country achieve the third 90 target with 90 percent of all people receiving ART having viral suppression!
Dr Brian Ziki, Collin Saunders Hospital, Triangle, Zimbabwe