Rolling out the technologies
Soon after the three disease areas were in place, it became apparent that it would be possible to develop integrated molecular platforms across diseases. This has enabled a more patient-centred approach to be adopted at FIND with technologies such as: liquid culture for drug susceptibility testing, line-probe assay, automated molecular detection and manual DNA amplification. This integrated molecular platform approach is expected to have the potential to host tests for Tuberculosis, Malaria, Human African Trypanosomiasis, Leishmaniasis and Early Infant Diagnosis for HIV. Some of these technologies make it possible for FIND to consider simple diagnostic tests at the community level nearer to where people live, making if possible for them to be more easily followed in their treatment.
For example, there are two technology platforms currently undergoing evaluation for application to human African trypanosomiasis (HAT).
a) A light emitting device (LED) -based fluorescence microscope developed for TB by FIND and Carl Zeiss which has become an excellent tool for parasite demonstration in HAT. The LED microscope is robust, affordable, can be operated with solar power and is perfectly suited to the rural settings where HAT occurs. Another advantage is the acridine orange staining procedure which delivers a result within 3 minutes of incubation as against 45 minutes for Giemsa. The commercial viability of this product is sustained by the TB market, so a reasonable manufacturing lifespan is guaranteed.
b) Loop-mediated isothermal amplification (LAMP) of DNA, is a simple molecular method developed by Eiken Chemical Co. in Japan. Since LAMP is carried out under isothermal conditions, a simple incubator such as a water bath or heat block is sufficient for DNA amplification. The reaction shows high tolerance to biological products, so that DNA extraction is not necessary. The technique uses a set of six primers that recognise eight sections of target DNA. Simultaneous synthesis of DNA by multiple primers makes LAMP highly sensitive and increases specificity, efficiency and rapidity. The product can be inspected visually by the addition of the fluorescent dye SYBR Green 1 or calcein, and measurement of turbidity derived from a precipitate of magnesium pyrophosphate in the reaction mixture.
By investing in platforms which apply to commercial markets and then piggy-backing neglected infectious diseases on them, FIND has moved closer to delivering on its promise of affordable and easy to use point of care diagnostics. Making this technology accessible at community level through appropriate healthcare strategies is the next challenge.