Characterization of Severe Acute Respiratory Syndrome Coronavirus 2 Omicron Variant Shedding and Predictors of Viral Culture Positivity on Vaccinated Healthcare Workers With Mild Coronavirus Disease 2019.

In this prospective cohort of 30 vaccinated healthcare workers with mild Omicron variant infection, we evaluated viral culture, rapid antigen test (RAT), and real-time reverse-transcription polymerase chain reaction (RT-PCR) of respiratory samples at days 5, 7, 10, and 14. Viral culture was positive in 46% (11/24) and 20% (6/30) of samples at days 5 and 7, respectively. RAT and RT-PCR (Ct ≤35) showed 100% negative predictive value (NPV), with positive predictive values (PPVs) of 32% and 17%, respectively, for predicting viral culture positivity. A lower RT-PCR threshold (Ct ≤24) improved culture prediction (PPV = 39%; NPV = 100%). Vaccinated persons with mild Omicron infection are potentially transmissible up to day 7. RAT and RT-PCR might be useful tools for shortening the isolation period.

Performance of at-home self-collected saliva and nasal-oropharyngeal swabs in the surveillance of COVID-19.

Background: SARS-CoV-2 quickly spreads in the worldwide population, imposing social restrictions to control the infection, being the massive testing another essential strategy to break the chain of transmission. Aim: To compare the performance of at-home self-collected samples - saliva and combined nasal-oropharyngeal swabs (NOP) - for SARS-CoV-2 detection in a telemedicine platform for COVID-19 surveillance. Material and methods: We analyzed 201 patients who met the criteria of suspected COVID-19. NOP sampling was combined (nostrils and oropharynx) and saliva collected using a cotton pad device. Detection of SARS-COV-2 was performed by using the Altona RealStar® SARS-CoV-2 RT-PCR Kit 1.0.  Results: There was an overall significant agreement (κ coefficient value of 0.58) between saliva and NOP. Considering results in either sample, 70 patients positive for SARS-CoV-2 were identified, with 52/70 being positive in NOP and 55/70 in saliva. This corresponds to sensitivities of 74.2% (95% CI; 63.7% to 83.1%) for NOP and 78.6% (95% CI; 67.6% to 86.6%) for saliva. Conclusion: Our data show the feasibility of using at-home self-collected samples (especially saliva), as an adequate alternative for SARS-CoV-2 detection. This new approach of testing can be useful to develop strategies for COVID-19 surveillance and for guiding public health decisions.

SARS-CoV-2 aerosol generation during respiratory equipment reprocessing.

Aerosolization may occur during reprocessing of medical devices. With the current coronavirus disease 2019 pandemic, it is important to understand the necessity of using respirators in the cleaning area of the sterile processing department. To evaluate the presence of severe acute respiratory syndrome coronavirus (SARS-CoV-2) in the air of the sterile processing department during the reprocessing of contaminated medical devices. Air and surface samples were collected from the sterile processing department of two teaching tertiary hospitals during the reprocessing of respiratory equipment used in patients diagnosed with coronavirus disease 2019 and from intensive care units during treatment of these patients. SARS-CoV-2 was detected only in 1 air sample before the beginning of decontamination process. Viable severe acute respiratory syndrome coronavirus 2 RNA was not detected in any sample collected from around symptomatic patients or in sterile processing department samples. The cleaning of respiratory equipment does not cause aerosolization of SARS-CoV-2. We believe that the use of medical masks is sufficient while reprocessing medical devices during the coronavirus disease 2019 pandemic.