Acute respiratory infections (ARIs) are the leading cause of death in children under five throughout the world . Both vaccination and early diagnosis are critical to appropriate treatments and preventing transmission. However, infants too young to be fully immunized are most at risk of contracting ARIs. Whooping cough alone, an infection due to Bordetella pertussis (B. pertussis), causes more than 300,000 deaths per year;90% of which occur in developing countries [2, 3]. While easily treated with first-line antibiotics more than half of all infants infected with B. pertussis require hospitalization, even in the US [2 4]. Because the initial symptoms of this bacterial infection are indistinguishable from viral ARIs, diagnosis based solely on clinical symptoms is impossible and many infants are not treated until it is too late. PCR-based molecular diagnostics performed on nasopharyngeal samples are the gold standard in B. pertussis detection. However, resource intensive equipment and technical training requirements prevent their use at the point-of-care (POC), especially in low- resource settings. A low-cost POC test for pertussis would enhance detection coverage and enable early detection resulting in improved treatment outcomes and prevention of further transmission. We hypothesize that capillary flow in ultra-low-cost paper modules can be used as a novel molecular diagnostic platform. We will develop both the individual modules for nucleic acid extraction, amplification, and detection, and their integration into a single POC device. The resulting paper-based molecular diagnostic test for B. pertussis will detect this deadly respiratory infection at the POC. The test will be hand-held, disposable, and instrument-free. This project will yield a validated proof-of-concept device suitable for future development activities including clinical testing. Ultimately, this work will develop a rapid molecular diagnosic platform that can be adapted to other diseases by simply altering the primer and probe targets in the isothermal amplification module.
Due to their exquisite sensitivity, molecular diagnostics are ideal vehicles for early detection of respiratory infections, such as pertussis, at the point-of-cae. Here we propose to develop a rapid molecular diagnostic that integrates modular nucleic acid extraction, amplification, and detection technologies into a single instrument-free device. Early detection provided by this point-of-care device would enable both improved clinical management and mediation of person-to-person transmission.
|Linnes, J C; Rodriguez, N M; Liu, L et al. (2016) Polyethersulfone improves isothermal nucleic acid amplification compared to current paper-based diagnostics. Biomed Microdevices 18:30|