Pandemic printing: a novel 3D‐printed swab for detecting SARS‐CoV‐2

Williams, Eloise; Bond, Katherine; Isles, Nicole; Chong, Brian; Johnson, Douglas; Druce, Julian; Hoang, Tuyet; Ballard, Susan A; Hall, Victoria; Muhi, Stephen; Buising, Kirsty L; Lim, Seok; Strugnell, Dick; Catton, Mike; Irving, Louis B; Howden, Benjamin P; Bert, Eric; Williamson, Deborah A

OBJECTIVES: To design and evaluate 3D‐printed nasal swabs for collection of samples for SARS‐CoV‐2 testing. DESIGN: An iterative design process was employed. Laboratory evaluation included in vitro assessment of mock nasopharyngeal samples spiked with two different concentrations of gamma‐irradiated SARS‐CoV‐2. A prospective clinical study compared SARS‐CoV‐2 and human cellular material recovery by 3D‐printed swabs and standard nasopharyngeal swabs. SETTING, PARTICIPANTS: Royal Melbourne Hospital, May 2020. Participants in the clinical evaluation were 50 hospital staff members attending a COVID‐19 screening clinic and two inpatients with laboratory‐confirmed COVID‐19. INTERVENTION: In the clinical evaluation, a flocked nasopharyngeal swab sample was collected with the Copan ESwab and a mid‐nasal sample from the other nostril was collected with the 3D‐printed swab. RESULTS: In the laboratory evaluation, qualitative agreement with regard to SARS‐CoV‐2 detection in mock samples collected with 3D‐printed swabs and two standard swabs was complete. In the clinical evaluation, qualitative agreement with regard to RNase P detection (a surrogate measure of adequate collection of human cellular material) in samples collected from 50 hospital staff members with standard and 3D‐printed swabs was complete. Qualitative agreement with regard to SARS‐CoV‐2 detection in three pairs of 3D‐printed mid‐nasal and standard swab samples from two inpatients with laboratory‐confirmed SARS‐CoV‐2 was also complete. CONCLUSIONS: Using 3D‐printed swabs to collect nasal samples for SARS‐CoV‐2 testing is feasible, acceptable to patients and health carers, and convenient.