Measurement of nitric oxide in exhaled air in primary school children in Ružomberok.

Nowadays, there are a number of respiratory illnesses that directly affect children. Exhaled nitric oxide measurement (FeNO) is one of the modern methods of investigation used for diagnosing and controlling allergic eosinophilic airway inflammation. It is a simple, painless and time-saving method for the patient. Because of its non-invasiveness and simplicity, it is a valuable diagnostic method, especially in younger children. Measurement of FeNO is a recognized biomarker and an accurate quantitative indicator in the detection, assessment and monitoring of airway inflammation, including asthma. However, only a few studies assess the relationship between FeNO and level of air pollution. The aim of our study is to determine the relationship between FeNO in third-grade students of primary schools and the level of air pollution in Ruzomberok. 146 children aged 8-10 years were included in the research. This is the first stage of a wider research project involving FeNO measurements in children at different times of the year. The goal of the research is to determine the concentration of FeNO in the studied group of children in the autumn when air pollution is lower than in second stage which is observed in winter. The study showed elevated values of FeNO>20 ppb in 11% of the tested children and correct values <20 ppb in 89% of them. Level of average air pollution in survey days for PM10 ranged from 23 to 40 μg/m3 and for NO2 – from 28 to 44 μg/m3. The study shows that the significant majority of children have normal levels of nitric oxide in the exhaled air when air pollution is low. Analysis of the second phase of FeNO measurements in winter, when air pollution was higher, will allow to compare the results and assess the correlation between the FeNO value and air pollution

SARS-CoV-2 Breakthrough Infections: Incidence and Risk Factors in a Large European Multicentric Cohort of Health Workers.

Background: The research aimed to investigate the incidence of SARS-CoV-2 breakthrough infections and their determinants in a large European cohort of more than 60,000 health workers. Methods: A multicentric retrospective cohort study, involving 12 European centers, was carried out within the ORCHESTRA project, collecting data up to 18 November 2021 on fully vaccinated health workers. The cumulative incidence of SARS-CoV-2 breakthrough infections was investigated with its association with occupational and social-demographic characteristics (age, sex, job title, previous SARS-CoV-2 infection, antibody titer levels, and time from the vaccination course completion). Results: Among 64,172 health workers from 12 European health centers, 797 breakthrough infections were observed (cumulative incidence of 1.2%). The primary analysis using individual data on 8 out of 12 centers showed that age and previous infection significantly modified breakthrough infection rates. In the meta-analysis of aggregated data from all centers, previous SARS-CoV-2 infection and the standardized antibody titer were inversely related to the risk of breakthrough infection (p = 0.008 and p = 0.007, respectively). Conclusion: The inverse correlation of antibody titer with the risk of breakthrough infection supports the evidence that vaccination plays a primary role in infection prevention, especially in health workers. Cellular immunity, previous clinical conditions, and vaccination timing should be further investigated