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Objective To assess whether aerosol generation occurs during otologic surgery, to define which instruments are aerosol generating, and to identify factors that enhance safety in protection against airborne pathogens, such as severe acute respiratory syndrome coronavirus 2. Study Design An observational prospective study on aerosol measurements during otologic operations recorded between August and December 2020. Setting Aerosol generation was measured with an Optical Particle Sizer as part of otologic operations with anesthesia. Particles with a size range of 0.3 to 10 mu m were quantified. Aerosol generation was measured during otologic operations to analyze aerosols during drilling in transcanal and transmastoid operations and when using the following instruments: bipolar electrocautery, laser, suction, and cold instruments. Coughing is known to produce significant concentration of aerosols and is commonly used as a reference for high-risk aerosol generation. Thus, the operating room background concentration and coughing were chosen as reference values. Patients Thirteen otologic operations were included. The average drilling time per surgery was 27.00 minutes (range, 2.00-71.80 min). Intervention Different rotation speeds during drilling and other instruments were used. Main Outcome Measures Aerosol concentrations during operations were recorded and compared with background and cough aerosol concentrations. Results Total aerosol concentrations during drilling were significantly higher than background (p < 0.0001, d = 2.02) or coughing (p < 0.0001, d = 0.50). A higher drilling rotation speed was associated with higher particle concentration (p = 0.037, eta(2) = 0.01). Aerosol generation during bipolar electrocautery, drilling, and laser was significantly higher than with cold instruments or suction (p < 0.0001, eta(2) = 0.04). Conclusion High aerosol generation is observed during otologic surgery when drill, laser, or bipolar electrocautery is used. Aerosol generation can be reduced by using cold instruments instead of electric and keeping the suction on during aerosol-generating procedures. If drilling is required, lower rotation speeds are recommended. These measures may help reduce the spread of airborne pathogens during otologic surgery.

Funding Information: Open Access funding provided by University of Helsinki. The study has been supported by The Finnish Dental Society Apollonia (grant for MP and LL), the Helsinki and Uusimaa Hospital District (HUS, grant for LL). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The data of this study has not been presented elsewhere. Publisher Copyright: © 2022, The Author(s). We examined the usefulness of dried spot blood and saliva samples in SARS-CoV-2 antibody analyses. We analyzed 1231 self-collected dried spot blood and saliva samples from healthcare workers. Participants filled in a questionnaire on their COVID-19 exposures, infections, and vaccinations. Anti-SARS-CoV-2 IgG, IgA, and IgM levels were determined from both samples using the GSP/DELFIA method. The level of exposure was the strongest determinant of all blood antibody classes and saliva IgG, increasing as follows: (1) no exposure (healthy, non-vaccinated), (2) exposed, (3) former COVID-19 infection, (4) one vaccination, (5) two vaccinations, and (6) vaccination and former infection. While the blood IgG assay had a 99.5% sensitivity and 75.3% specificity to distinguish participants with two vaccinations from all other types of exposure, the corresponding percentages for saliva IgG were 85.3% and 65.7%. Both blood and saliva IgG-seropositivity proportions followed similar trends to the exposures reported in the questionnaires. Self-collected dry blood and saliva spot samples combined with the GSP/DELFIA technique comprise a valuable tool to investigate an individual’s immune response to SARS-CoV-2 exposure or vaccination. Saliva IgG has high potential to monitor vaccination response wane, since the sample is non-invasive and easy to collect.

Saliva is an alternative sample material to nasopharyngeal swab in SARS-CoV-2 diagnostics. We investigated possible aspects to improve the reliability of SARS-CoV-2 detection from saliva. Saliva was collected from asymptomatic healthy subjects (n=133) and COVID-19 patients (n=9). SARS-CoV-2 detection was performed with quantitative reverse-transcriptase PCR (RT-qPCR) with two viral and one host target serving as an internal control. The use of internal control revealed that in the first RT-qPCR run 25–30 % of assays failed. The failure is associated with poor RNA quality. When the amount of RNA was cut down to half from the original amount, the performance of RT-qPCR was greatly enhanced (95 % of the assays succeeded). The quality of RNA was not affected by the use of different nucleic acid stabilizing buffers. Our study showed that saliva is suitable material for RT-qPCR based SARS-CoV-2 diagnostics, but the use of internal control is essential to distinguish the true negative samples from failed assays.

COVID-19 has highlighted the need for indoor risk-reduction strategies. Our aim is to provide information about the virus dispersion and attempts to reduce the infection risk. Indoor transmission was studied simulating a dining situation in a restaurant. Aerosolized Phi6 viruses were detected with several methods. The aerosol dispersion was modeled by using the Large-Eddy Simulation (LES) technique. Three risk-reduction strategies were studied: (1) augmenting ventilation with air purifiers, (2) spatial partitioning with dividers, and (3) combination of 1 and 2. In all simulations infectious viruses were detected throughout the space proving the existence long-distance aerosol transmission indoors. Experimental cumulative virus numbers and LES dispersion results were qualitatively similar. The LES results were further utilized to derive the evolution of infection probability. Air purifiers augmenting the effective ventilation rate by 65% reduced the spatially averaged infection probability by 30%-32%. This relative reduction manifests with approximately 15 min lag as aerosol dispersion only gradually reaches the purifier units. Both viral findings and LES results confirm that spatial partitioning has a negligible effect on the mean infection-probability indoors, but may affect the local levels adversely. Exploitation of high-resolution LES jointly with microbiological measurements enables an informative interpretation of the experimental results and facilitates a more complete risk assessment.

Our aim was to validate a Finnish version of the Eating Assessment Tool (F-EAT-10) for clinical use and to test its reliability and validity in a multicenter nationwide study. Normative data were acquired from 180 non-dysphagic participants (median age 57.0 years, 62.2% female). Dysphagia patients (n = 117, median age 69.7 years, 53.0% female) referred to fiberoptic endoscopic evaluation of swallowing (FEES) completed F-EAT-10 before the examination and after 2 weeks. Patients underwent the 100-ml water swallow test (WST) and FEES was evaluated using the following three scales: the Yale Pharyngeal Residue Severity Rating Scale, Penetration-Aspiration Scale, and the Dysphagia Outcome Severity Scale. An operative cohort of 19 patients (median age 75.8 years, 57.9% female) underwent an endoscopic operation on Zenker's diverticulum, tight cricopharyngeal muscle diagnosed in videofluorography, or both. Patients completed the F-EAT-10 preoperatively and 3 months postoperatively. The cut-off score for controls was 3 (sensitivity 94.0%, specificity 96.1%) suggesting that ≥ 3 is abnormal. Re-questionnaires for test-retest reliability analysis were available from 92 FEES patients and 123 controls. The intraclass correlation coefficient was excellent for the total F-EAT-10 score (0.93, 95% confidence interval 0.91-0.95). Pearson correlation coefficients were strong (p 0.001) for each of the questions and the total score. Internal consistency as assessed by Cronbach's alpha was excellent (0.95). Some correlations between findings in FEES and 100-ml WST with F-EAT-10 were observed. The change in subjective symptoms of operative patients paralleled the change in F-EAT-10. F-EAT-10 is a reliable, valid, and symptom-specific patient-reported outcome measure for assessing dysphagia among Finnish speakers.