Article Text
Abstract
Introduction Self vaginal sampling is a new collection approach for detection of Sexually Transmitted Infections and is able to guarantee privacy and comfort during the collection. The aim of the study was to evaluate usability, vaginal cells collection efficiency and ability to preserve nucleic acids stability of a new self vaginal flocked swab (FLOQSwabTM, Copan) developed for home collection.
Methods 80 donors (age 18 to 45) performed a double self-vaginal sampling (n=160) using: a certified flocked self-vaginal point of care collection (POC) device as a reference method (Copan); a new home-based self-vaginal flocked swab by following the kit instructions. Patients received a questionnaire to assess the usability of the new device. Home-based and POC self-vaginal swabs have been processed using Xpert CT/NG assay (Cepheid). The threshold cycle value (Ct) of a human genomic target (sample adequacy control), Ct of pathogens (Chlamydia trachomatis CT and Neisseria gonorrhoeae GC2 and GC4) and extraction and amplification control (Bacillus globigii spores) were considered to compare performance between the two devices. To evaluate the stability of the nucleic acids at time 0 and after 4 weeks of storage at +4 ° C and +30 ° C, 54 negative home collected self vaginal flocked samples have been inoculated with a suspension of CT and GC ATCC (VR880-43069) at 1 and 10xLOD of molecular assay.
Results 100% of overall agreement was obtained comparing the results between the two devices: 77/80 negative and 3/80 Chlamydia trachomatis positive patients were detected. No failure results have been observed. The survey reported a better appreciated home-based self vaginal collection (80%) with respect to the POC sampling. After 4 weeks of storage at 4°C and at 30°C all 54 spiked samples have been correctly detected.
Conclusion the new home-based self vaginal device has shown the same performance of the reference swab, demonstrating an efficient recovery of vaginal cells, stability of CT and GC nucleic acids up to 4 weeks at 4°C and +30°C and excellent acceptability by women.