Integrated ultrasonic biosensing for point-of-care diagnostics

Context Nearly 260 million people are infected with schistosomiasis with >90% of infections found in sub-Saharan Africa. There is a need to develop new highly sensitive diagnostic methods that enable to monitor treatment outcomes, with the specific aims of (i) preventing re-emergence of infections following local treatment; and (ii) reducing resistance by ensuring effective and appropriate treatment.
Aims: We will develop a new low-cost, rapid (<30 min), point-of-care, highly sensitive stool-based test which the ability to detect S. mansoni (eggs), and Schistosoma hybrids using a paper based (low cost) DNA assay based upon isothermal amplification (e.g. LAMP). The device will separate the eggs, lyse the sample and detect species specific DNA. We aim to obtain initial proof-of-concept data of the performance of the device in the field in Uganda on patients' samples. To our knowledge, this will be the first instance of these low cost methods for looking at stool based samples and has the future potential applications in a range of other helminth infections.

The schistosoma live in the hepatic portal vein and shed cells into the blood. In parallel with the stool test, we will therefore also develop a blood based assay, where DNA will be detected from a fingerpick of blood. The assay will again be configured as a low cost, paper based assay and will be developed as a duplex, enabling both malaria and bliharzia (schistosomiasis) to be detected at the same time. This will guide appropriate treatment for febrile patients

Through enabling low-cost, point-of-care genomic diagnostics, the project aligns specifically with EPSRC's Healthcare Technology theme, including optimising treatment by monitoring efficacy, developing capabilities in priority research areas such as Engineering and Sensors. This research is based on fundamental developments in SAW made in EPSRC-funded activity (Cooper fellowship, Proxomics project).

Benefits: This project is aligned with the Health priority of the Global Challenge Fund, which aims 'to tackle diseases, strengthen health systems and reach the worlds' most vulnerable'. Inded, according to the latest WHO estimates, at least 258 million people have required treatment for Schistosomiasis in 2014, with 61.6 million people reported to be treated. 90% of those requiring treatment live in Africa. In children, Schistosomiasis causes anaemia, stunted growth and reduced ability to learn. Treatment usually reverses these effects, but its efficacy need to be monitored to establish cure and adapt therapy. If untreated, chronic disease affects people's ability to work and can result in death. The disease burden has been estimated to account for 4.5 million DALYs (disability affected life years).

Mass drug administration of praziquantel has been delivered through National Control Programmes in Uganda for over a decade. Hotspots of infection have been detected, where prevalence, intensity and associated morbidity are now higher than they were at baseline. Emergence of praziquantel resistance through over-use or in appropriate use is seen as a major threat. Field based diagnosis, with local communities, is key to ensure that appropriate administration of the drug is carried out until treatment is complete, without over exposure.

Collaborators. Dr. Edridah Muheki Tukahebwe, Ministry of Health, Uganda; Track record in research: Dr Poppy Lamberton (MVLS) will help with field studies and has a long established collaboration with Dr Tukahebwe.