JMIR Publications

ABSTRACT

Background:

Cholera poses a significant global health burden. In Bangladesh, cholera is endemic and causes more than 100,000 cases each year. Established environmental reservoirs leave millions at risk of infection through the consumption of contaminated water. The Global Task Force for Cholera Control has called for increased environmental surveillance to detect contaminated water sources prior to human infection in an effort to reduce cases and deaths. The OmniVis rapid cholera detection devices utilize loop-mediated isothermal amplification and particle diffusometry detection methods integrated into a handheld hardware device that attaches to an iPhone 6 to identify and map contaminated water sources.

Objective:

The aim of this study was to evaluate the usability of the OmniVis device with targeted end-users in order to advance the iterative prototyping process and ultimately design a device that easily integrates into users’ workflow.

Methods:

Water quality workers were trained to use the device and subsequently completed an independent device trial and usability questionnaire. Pre- and post-training knowledge assessments were administered to ensure training quality did not confound trial and questionnaire results.

Results:

Device trials identified common user errors and device malfunctions, including incorrect test kit insertion and device powering issues. We did not observe meaningful differences in user errors or device malfunction accumulated per participant across demographic groups. Over 25 trials, the mean time to complete a test was 47 minutes, a significant reduction compared to gold standard laboratory protocols, which takes around 3 days. Overall, participants found the device easy-to-use and expressed confidence and comfort in using the device independently.

Conclusions:

These results are used to advance the iterative prototyping process of the OmniVis rapid cholera detection device so that it can achieve user uptake, workflow integration, and scale to ultimately impact cholera control and elimination strategies. We hope that this methodology will promote robust usability evaluations of rapid pathogen detection technologies in device development.