Pandemic printing: a novel 3D-printed swab for detectingSARS-CoV-2

Objectives To design and evaluate 3D-printed nasal swabs for collection of samples forSARS-CoV-2 testing. Design An iterative design process was employed. Laboratory evaluation includedin vitroassessment of mock nasopharyngeal samples spiked with two different concentrations of gamma-irradiatedSARS-CoV-2. A prospective clinical study comparedSARS-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 aCOVID-19 screening clinic and two inpatients with laboratory-confirmedCOVID-19. Intervention In the clinical evaluation, a flocked nasopharyngeal swab sample was collected with the CopanESwab 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 toSARS-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 toRNase 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 toSARS-CoV-2 detection in three pairs of 3D-printed mid-nasal and standard swab samples from two inpatients with laboratory-confirmedSARS-CoV-2 was also complete. Conclusions Using 3D-printed swabs to collect nasal samples forSARS-CoV-2 testing is feasible, acceptable to patients and health carers, and convenient.