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Every year infectious diseases are among the top major causes of death worldwide. Infectious diseases disproportionately impact resource-poor areas. While most developed countries have the ability to screen and quickly detect infectious diseases in humans, animals, and plants, developing countries lack this ability. In such areas, access to medical treatment and testing facilities is severely limited. Additionally, developing countries are more densely populated, which makes infectious disease surveillance exceedingly more difficult. As a result of this, infectious diseases tend to spread more quickly and outbreaks tend to occur more often in developing countries. Additionally, the increasing rate of antimicrobial resistant infections and emergence of novel infectious diseases increase the likelihood of global pandemic occurrence. It is evident that developing novel devices for detection of infectious diseases would be greatly beneficial to global health. It is important to note that developed countries would benefit equally from such a device. Pandemics tend to burden the economy and put strain on resources even in developed countries. The impact of such a device is determined by a set of criteria put forth by the World Health Organization (WHO). Based on the ASSURED criteria, an ideal device for point-of-care (POC) diagnostics must be affordable, sensitive, specific; and yet it must also be user-friendly, rapid and robust, equipment free, and deliverable to end-users. Additionally, this device must be easily adaptable for detection of novel pathogens. The nucleic acid amplification test (NAAT) meets many of these criteria. However, NAAT’s current workflow involves many user liquid handling steps as well as a thermocycler. This thesis aims to address these issues by first automating isothermal nucleic acid amplification, followed by coupling the amplification step with the lateral-flow immunoassay (LFA), which is a paper-based diagnostic device. Thus, taking advantage of the affordability and POC features of the LFA. The aim of these efforts is to work toward the ultimate goal of developing a device that receives the patient sample, then carries out all the steps in NAAT in an automated manner and produces results with just a push of a single button.

Trichomonas vaginalis is a prevalent sexually transmitted infection (STI). Diagnosis has historically relied on either microscopic analysis or culture, the latter being the previous gold standard. However, these tests are not readily available for male diagnosis, generally only perform well for symptomatic women, and are not as sensitive as nucleic acid amplification tests (NAATs). Men are largely asymptomatic but carry the organism and transmit to their sexual partners. This multicenter, prospective study evaluated the performance of the cobas T. vaginalis/Mycoplasma genitalium (TV/MG) assay for detection of T. vaginalis DNA compared with patient infection status (PIS) defined by a combination of commercially available NAATs and culture using urogenital specimens. A total of 2,064 subjects (984 men and 1,080 women, 940 [45.5%] symptomatic, 1,124 [54.5%] asymptomatic) were evaluable. In women, sensitivity ranged from 99.4% (95% confidence interval [CI] 96.8 to 99.9%) using vaginal samples to 94.7% (95% CI 90.2 to 97.2%) in PreservCyt samples. Specificity ranged from 98.9 to 96.8% (95% CI 95.4 to 97.8%). In men, the cobas TV/MG assay was 100% sensitive for the detection of T. vaginalis in both male urine samples and meatal swabs, with specificity of 98.4% in urine samples and 92.5% in meatal swabs. The cobas TV/MG is a suitable diagnostic test for the detection of T. vaginalis, which could support public health efforts toward infection control and complement existing STI programs.