Blood and saliva SARS-CoV-2 antibody levels in self-collected dried spot samples.

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 and serum biomarkers in periodontitis and coronary artery disease.

AIM: Matrix metalloproteinase (MMP)-8, MMP-9, tissue inhibitor of matrix metalloproteinase (TIMP)-1 and myeloperoxidase (MPO) participate in extracellular matrix breakdown both in periodontium and atherosclerotic plaques. We investigated the diagnostic value of serum and saliva biomarkers in periodontitis and acute coronary syndrome (ACS). MATERIALS AND METHODS: The population was PAROGENE (n = 481), a random cohort of patients with an indication for coronary angiography. All patients underwent a clinical and radiographic oral examination. Groups consisting of periodontitis versus non-periodontitis, and ACS versus non-ACS patients were compared. RESULTS: Saliva MMP-8, MMP-9 and MPO provided significant area-under-curve (AUC) values for periodontitis, 0.69 (<0.001), 0.66 (<0.001) and 0.68 (<0.001), respectively. Serum MMP-8, MMP-9 and MPO levels distinguished ACS from non-ACS patients with AUCs of 0.73 (<0.001), 0.58 (0.03) and 0.68 (<0.001), respectively. Periodontitis confounded the use of serum MMP-9 in diagnostics of ACS. Cardiac status complicated the use of saliva TIMP-1 in periodontal diagnostics. Saliva biomarkers could not be used in ACS diagnosis, and serum biomarkers were not useful in diagnosis of periodontitis. CONCLUSIONS: MMP-8, MMP-9, TIMP-1and MPO are valuable biomarkers for both ACS and periodontitis, but the selection of sample material is crucial; serum is suitable for ACS and saliva for periodontal diagnostic aid.

Working conditions during the COVID-19 pandemic in primary and tertiary healthcare: a comparative cross-sectional study.

OBJECTIVES: The COVID-19 pandemic has globally affected healthcare workers' (HCWs) health and wellbeing. Most studies on COVID-19 have focused on tertiary healthcare. The aim of this study was to increase the knowledge on the effects of the pandemic on working conditions in tertiary and primary healthcare. MATERIAL AND METHODS: The comparative cross-sectional study consisted of an online questionnaire sent to HCWs of the City of Helsinki (primary healthcare) and Helsinki University Hospital (tertiary healthcare). Altogether 1580 HCWs with direct patient contact participated in the study: 895 from tertiary and 685 from primary healthcare. Statistical analysis used SPSS 25 from IBM. The tests used were the χ2 test, Fisher's exact test, and binary logistic regression analysis. RESULTS: Primary HCWs were less likely to treat COVID-19 patients (OR = 0.45, 95% CI: 0.37-0.56). However, both groups reported a similar number of COVID-19 infections, primary HCWs 4.9% and tertiary HCWs 5.0%, and workrelated quarantine was significantly more prevalent (OR = 1.96, 95% CI: 1.38-2.79) among primary HCWs. In addition, work-related wellbeing was poorer among primary HCWs than tertiary HCWs in terms of feeling more stressed at work (OR = 3.20, 95% CI: 2.55-4.02), not recovering from work (OR = 0.49, 95% CI: 0.39-0.62), reported mental wellbeing below normal levels (OR: 1.59, 95% CI: 1.26-2.00), and increased working hours (OR = 1.63, 95% CI: 1.25-2.12). CONCLUSIONS: The study demonstrates how the pandemic has affected the wellbeing and working conditions of not only tertiary but also less studied primary HCWs. The authors' findings suggest that the challenges identified during the COVID-19 pandemic in the health and wellbeing of healthcare workers are even greater in primary care than in tertiary care. Int J Occup Med Environ Health. 2023;36(1):139-50.

"As protective gear began to run low, guidance on protection became looser" - Healthcare workers' perspectives on infection prevention and control during the COVID-19 pandemic.

Objectives: The COVID-19 pandemic has posed several risk factors to healthcare workers' (HCWs') emotional distress. The purpose of the study was to enhance understanding of the experiences and feelings of HCWs during the COVID-19 pandemic, with specific reference to infection prevention and control (IPC) practices and guidance, focusing on the quality and availability of personal protective equipment (PPE), guidelines, and management. With a qualitative approach, we aimed to enable a wider narrative; to gain a more detailed understanding related to PPE use and identify experiences that can be overlooked in forced-choice questionnaires. Methods: An online questionnaire was conducted among HCWs of the City of Helsinki and Helsinki University Hospital between 12.6.2020 and 5.4.2021. Altogether 1,580 HCWs participated in the study, from whom 579 shared 1,666 free-text responses. These responses were analyzed qualitatively, and the results were combined with statistical data on the participants' working conditions and backgrounds. Results: We identified problems in PPE availability and changing guidelines as factors causing the most distress in the participants. Regarding availability, running out of masks and respirators emerged as the most worrying issue, and inadequate PPE was associated with the excessive workload (OR 1.51, CI 95% 1.01-2.25). The results also highlight the importance of transparent and clear communication regarding IPC instructions and guidance, and clear IPC guidance was associated with better levels of reported recovery from work (OR 1.51, CI 95% 1.06-2.14). Conclusions: Our study highlights the importance of adequate PPE provision, transparent communication, clear guidance, and supportive supervisory work in this ongoing pandemic and potential new ones. We suggest more rigorous preparation, with crisis communication planning and emergency storage of PPE.

Effect of RNA quality to SARS-CoV-2 RT-qPCR detection from saliva.

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.

Aerosol concentrations and size distributions during clinical dental procedures.

Background: Suspected aerosol-generating dental instruments may cause risks for operators by transmitting pathogens, such as the SARS-CoV-2 virus. The aim of our study was to measure aerosol generation in various dental procedures in clinical settings. Methods: The study population comprised of 84 patients who underwent 253 different dental procedures measured with Optical Particle Sizer in a dental office setting. Aerosol particles from 0.3 to 10 µm in diameter were measured. Dental procedures included oral examinations (N = 52), restorative procedures with air turbine handpiece (N = 8), high-speed (N = 6) and low-speed (N = 30) handpieces, ultrasonic scaling (N = 31), periodontal treatment using hand instruments (N = 60), endodontic treatment (N = 12), intraoral radiographs (N = 24), and dental local anesthesia (N = 31). Results: Air turbine handpieces significantly elevated <1 µm particle median (p = 0.013) and maximum (p = 0.016) aerosol number concentrations as well as aerosol particle mass concentrations (p = 0.046 and p = 0.006) compared to the background aerosol levels preceding the operation. Low-speed dental handpieces elevated >5 µm median (p = 0.023), maximum (p = 0.013) particle number concentrations,> 5 µm particle mass concentrations (p = 0.021) and maximum total particle mass concentrations (p = 0.022). High-speed dental handpieces elevated aerosol concentration levels compared to the levels produced during oral examination. Conclusions: Air turbine handpieces produced the highest levels of <1 µm aerosols and total particle number concentrations when compared to the other commonly used instruments. In addition, high- and low-speed dental handpieces and ultrasonic scalers elevated the aerosol concentration levels compared to the aerosol levels measured during oral examination. These aerosol-generating procedures, involving air turbine, high- and low-speed handpiece, and ultrasonic scaler, should be performed with caution. Clinical significance: Aerosol generating dental instruments, especially air turbine, should be used with adequate precautions (rubber dam, high-volume evacuation, FFP-respirators), because aerosols can cause a potential risk for operators and substitution of air turbine for high-speed dental handpiece in poor epidemic situations should be considered to reduce the risk of aerosol transmission.

A machine learning approach to predict resilience and sickness absence in the healthcare workforce during the COVID-19 pandemic.

During the COVID-19 pandemic, healthcare workers (HCWs) have faced unprecedented workloads and personal health risks leading to mental disorders and surges in sickness absence. Previous work has shown that interindividual differences in psychological resilience might explain why only some individuals are vulnerable to these consequences. However, no prognostic tools to predict individual HCW resilience during the pandemic have been developed. We deployed machine learning (ML) to predict psychological resilience during the pandemic. The models were trained in HCWs of the largest Finnish hospital, Helsinki University Hospital (HUS, N = 487), with a six-month follow-up, and prognostic generalizability was evaluated in two independent HCW validation samples (Social and Health Services in Kymenlaakso: Kymsote, N = 77 and the City of Helsinki, N = 322) with similar follow-ups never used for training the models. Using the most predictive items to predict future psychological resilience resulted in a balanced accuracy (BAC) of 72.7-74.3% in the HUS sample. Similar performances (BAC = 67-77%) were observed in the two independent validation samples. The models' predictions translated to a high probability of sickness absence during the pandemic. Our results provide the first evidence that ML techniques could be harnessed for the early detection of COVID-19-related distress among HCWs, thereby providing an avenue for potential targeted interventions.

Systemic Antibiotics Influence Periodontal Parameters and Oral Microbiota, But Not Serological Markers.

The use of systemic antibiotics may influence the oral microbiota composition. Our aim was to investigate in this retrospective study whether the use of prescribed antibiotics associate with periodontal status, oral microbiota, and antibodies against the periodontal pathogens. The Social Insurance Institution of Finland Data provided the data on the use of systemic antibiotics by record linkage to purchased medications and entitled reimbursements up to 1 year before the oral examination and sampling. Six different classes of antibiotics were considered. The Parogene cohort included 505 subjects undergoing coronary angiography with the mean (SD) age of 63.4 (9.2) years and 65% of males. Subgingival plaque samples were analysed using the checkerboard DNA-DNA hybridisation. Serum and saliva antibody levels to periodontal pathogens were analysed with immunoassays and lipopolysaccharide (LPS) activity with the LAL assay. Systemic antibiotics were prescribed for 261 (51.7%) patients during the preceding year. The mean number of prescriptions among them was 2.13 (range 1-12), and 29.4% of the prescriptions were cephalosporins, 25.7% penicillins, 14.3% quinolones, 12.7% macrolides or lincomycin, 12.0% tetracycline, and 5.8% trimethoprim or sulphonamides. In linear regression models adjusted for age, sex, current smoking, and diabetes, number of antibiotic courses associated significantly with low periodontal inflammation burden index (PIBI, p < 0.001), bleeding on probing (BOP, p = 0.006), and alveolar bone loss (ABL, p = 0.042). Cephalosporins associated with all the parameters. The phyla mainly affected by the antibiotics were Bacteroidetes and Spirochaetes. Their levels were inversely associated with the number of prescriptions (p = 0.010 and p < 0.001) and directly associated with the time since the last prescription (p = 0.019 and p < 0.001). Significant inverse associations were observed between the number of prescriptions and saliva concentrations of Prevotella intermedia, Tannerella forsythia, and Treponema denticola and subgingival bacterial amounts of Porphyromonas gingivalis, P. intermedia, T. forsythia, and T. denticola. Saliva or serum antibody levels did not present an association with the use of antibiotics. Both serum (p = 0.031) and saliva (p = 0.032) LPS activity was lower in patients having any antibiotic course less than 1 month before sampling. Systemic antibiotics have effects on periodontal inflammation and oral microbiota composition, whereas the effects on host immune responses against the periodontal biomarker species seem unchanged.

Smoking confounds the periodontal diagnostics using saliva biomarkers.

BACKGROUND: Smoking is a risk factor for periodontal disease because of its complex impact on the inflammatory response in the periodontium. We investigated the effect of smoking on salivary periodontal biomarkers, matrix metalloproteinase (MMP)-8, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-1 and myeloperoxidase (MPO). METHODS: Saliva biomarkers were analyzed in the Parogene population (n = 480) comprising a random cohort of patients that have undergone coronary angiography and oral examination. The effect of time since cessation and pack years of smoking on biomarkers were investigated. RESULTS: Saliva MMP-8, MMP-9, TIMP-1, and MPO concentrations distinguished periodontitis patients significantly from patients without periodontitis. When the time since cessation was considered, the area-under-the-curve values (p-value) for periodontitis were 0.76 (<0.001), 0.74 (<0.001), 0.70 (<0.001), and 0.76 (<0.001), respectively. Adding information about smoking habits in the models improved slightly the sensitivities of all biomarkers. In logistic regression model saliva, MMP-8 was mainly affected by pack years of smoking, whereas saliva MMP-9, TIMP-1, and MPO were mostly affected by time since cessation, especially if smoking currently or quit recently (<1 year ago). CONCLUSION: Smoking confounds the salivary diagnostics of periodontitis and should be considered when interpreting the results obtained by potential diagnostic tests.

Serum MMP-9 Diagnostics, Prognostics, and Activation in Acute Coronary Syndrome and Its Recurrence.

Matrix metalloproteinase (MMP)-9 is crucial in atherosclerotic plaque rupture and tissue remodeling after a cardiac event. The balance between MMP-9 and endogenous inhibitor, tissue inhibitors of matrix metalloproteinase 1 (TIMP-1), is important in acute coronary syndrome (ACS). This is an age- and gender-matched case-control study of ACS (N = 669). Patients (45.7%) were resampled after recovery, and all were followed up for 6 years. The molecular forms of MMP-9 were investigated by gelatin zymography. Diagnostically, MMP-9 and the MMP-9/TIMP-1 molar ratio were associated with ACS (OR 5.81, 95% CI 2.65-12.76, and 4.96, 2.37-10.38). The MMP-9 concentrations decreased 49% during recovery (p < 0.001). The largest decrease of these biomarkers between acute and recovery phase (ΔMMP-9) protected the patients from major adverse cardiac events, especially the non-fatal events. The fatal events were associated with in vitro activatable MMP-9 levels (p = 0.028). Serum MMP-9 and the MMP-9/TIMP-1 molar ratio may be valuable in ACS diagnosis and prognosis. High serum MMP-9 activation potential is associated with poor cardiovascular outcome.

Biomarkers of periodontitis and inflammation in ischemic stroke: A case-control study.

Periodontitis is a common infectious disease associated with increased risk for ischemic stroke though presently unclear mechanisms. In a case-control study, we investigated salivary levels of four periodontal pathogens, as well as systemic and local inflammatory markers. The population comprised 98 patients with acute ischemic stroke (mean ± SD, 68.2 ± 9.7 yrs; 45.9% women) and 100 healthy controls (69.1 ± 5.2 yrs; 47.0% women). Patients were more often edentulous and had fewer teeth than controls (13.8 ± 10.8 versus 16.6 ± 10.1). After adjusting for stroke risk factors and number of teeth, controls had higher saliva matrix metalloproteinase-8 (MMP-8), myeloperoxidase (MPO), IL-1ß, Aggregatibacter actinomycetemcomitans, and serum LPS activity levels. Patients had higher serum MMP-8 and MPO, and they were more often qPCR-positive for A. actinomycetemcomitans (37.9% versus 19.0%) and for ≥3 periodontopathic species combined (50.0% versus 33.0%). We conclude that controls more often had evidence of current periodontal infection with higher periodontal pathogen amount, endotoxemia, local inflammation and tissue destruction. Stroke patients more often had evidence of end-stage periodontitis with edentulism and missing teeth. They were more often carriers of several periodontopathic pathogens in saliva, especially A. actinomycetemcomitans. Additionally, inflammatory burden may contribute to high systemic inflammation associated with elevated stroke susceptibility.