No Evidence of SARS-CoV-2 on Endoscopes

  • An Italian pilot study investigated how effectively SARS-CoV-2 is eliminated by reprocessing endoscopes [1].

  • Swabs were taken from 13 endoscopes at three different points in time, and the samples were analyzed using a real-time polymerase chain reaction (RT-PCR) test.

  • SARS-CoV-2 material could not be detected on any of the endoscopes examined.

Do reprocessed endoscopes pose a risk of transmission of SARS-CoV-2? An Italian pilot study provides important insights in this matter [1]. The study investigated how effectively SARS-CoV-2 is eliminated by reprocessing endoscopes using peracetic acid during the disinfection stage [1]. Swabs taken from 13 endoscopes were analyzed after these had been used in 12 SARS-CoV-2-positive or critically ill COVID-19 patients. Different types of endoscopes were examined in this study, including six gastroscopes, three colonoscopes, two bronchoscopes, one duodenoscope, and one ultrasound endoscope [1].

Genetic analysis yields surprising results

The swabs taken from several endoscope sites were taken at three different points in time: once immediately before use on patients, then immediately after use, and finally after the endoscopes had been reprocessed. In order to detect genetic fragments of SARS-CoV-2, the swabs were immediately analyzed in the hospital’s virology laboratory using an RT-PCR test.

The results of the analyses were surprising. As anticipated, the swabs taken immediately before examination were negative. As expected, the swabs taken after the endoscopes were reprocessed were also negative in the analysis. However, it is worth noting that the swabs taken immediately after the endoscopic procedure also produced negative results. This is despite the fact that the threshold value for detecting SARS-CoV-2 was chosen such that even a minimal viral load would have been identified in the analyses.

The authors currently have no explanation for this result [1]. However, it can be concluded from the study that the risk of transmission of SARS-CoV-2 through correctly prepared endoscopes is very low [1].

Sources and further readings

  1. Boškoski I et al. Endoscopes used in positive and critically ill patients are SARS-CoV-2 negative at virological assessment, Gut 2021;0:1-3.