Background/Objectives: Healthcare workers (HCWs) were the most exposed job category to SARS-CoV-2, due to patient care, HCW-to-HCW transmission, and community exposure. However, the relative relevance of each source is still debated. To address this issue, this study investigated the dynamics of the professional and extra-professional determinants of infection across the pandemic among a large, multicenter cohort of HCWs. Methods: The study included 5576 HCWs from four Italian University Hospitals within a European Project, called ORCHESTRA. Socio-demographic and clinical data were collected retrospectively via online surveys from March 2020 to September 2022. Factors associated with SARS-CoV-2 infection during different pandemic periods were evaluated by a multinomial logistic regression model. Results were expressed as Relative Risk Ratios (RRR). Results: The cumulative incidence was 46.2%. The highest incidence period was the Omicron phase (OVP) (69.7%). The extra-professional source was the most reported (34.3%), followed by the occupational (26.8%). However, in almost 40%, the source was undetected. The RRR for occupational exposures was 0.39 (95% CI 0.25-0.61) during the Pre-Omicron variant Period (POP) and even lower (0.22, 95% CI 0.16-0.29) in the OVP, as compared to extra-professional exposures, using the Pre-Vaccination Period (PVP) as reference. Conclusions: The dominant source of infection among HCWs changed over time. While occupational contacts were more frequent during PVP, it significantly waned over the subsequent pandemic phases. Implementing procedures and guidelines to prevent infection, even outside the workplace during pandemics, would reduce the spread of infection among HCWs and patients.

Background and Objective:Fractional exhaled nitric oxide (FeNO) is a biomarker of type-2 lung inflammation. Standardized measurement is essential for accurate diagnosis and monitoring. We assess seasonality and environmental determinants of FeNO in individuals with and without chronic respiratory diseases in the general population. Methods:This is a cross-sectional study on 412 individuals with chronic respiratory diseases (asthma, chronic bronchitis/chronic obstructive pulmonary disease, rhinitis) and 605 individuals without these conditions. Participants, aged 20-65 years, were recruited in the Gene-Environment Interactions in Respiratory Diseases study in Verona, Italy (2008-2014). Geocoded residential addresses were linked to daily PM10 and air temperature at the time of the clinical examination using previously developed spatiotemporal models. Associations with log-FeNO were analyzed using adjusted linear regression, accounting for seasonality and disease status. Results:FeNO levels were higher in subjects with respiratory diseases during the warm season, even after adjusting for pollen exposures; a milder seasonal pattern was observed in subjects without chronic respiratory diseases (P for interaction = 0.001). A 10 μg/m3 increase in mean PM10 concentration at lag 0-1 (day of FeNO measurement and day before) was associated with a 3% higher FeNO concentration (Ratio of Geometric Means, RGM: 1.03, 95% confidence interval: 1.00, 1.06) after adjusting for seasonality. Conclusion:FeNO is a sensitive biomarker of environmental exposures. Overlooking seasonality and environmental factors might impact clinical decision-making in chronic respiratory diseases.

Obstructive sleep apnea (OSA) is a very common but underdiagnosed health disorder. OSA-derived cognitive disorders could increase the risk of work-related injuries among healthcare workers (HW), representing a major threat both to them and their patients. This study aimed to conduct a systematic review and meta-analysis to assess the relevance of OSA in the healthcare sector. Studies reporting the prevalence of either high risk of OSA (HRO) or diagnosed OSA, assessed respectively by structured questionnaires or validated diagnostic tools among healthcare workers, published between 2000 and 2026 in PubMed and Scopus were included. A meta-analysis of the included papers was performed using random-effects models to estimate the pooled prevalence. Variability was evaluated by the heterogeneity test and the I² statistic. Statistical significance was set at p < 5%. Of the 211 articles identified, 9 with 8473 participants were included in the meta-analysis. OSA risk was assessed by the Berlin (BQ) and STOP-BANG questionnaires (SBQ) in 6 and 3 studies, respectively. Prevalence estimates for HRO were highly heterogeneous (I-squared = 99.1%), ranging from 7 to 37%. The pooled estimate was 23% (95% CI 13-33%). Prevalence estimates were significantly affected by geographic area, being higher in Europe and the Middle East than in South-East Asia and the US (p < 0.01), but neither by response rate nor by the questionnaire used. The prevalence of OSA diagnosis was instrumentally obtained only in two studies and ranged from 9.3 to 21.9%. Data on HRO prevalence among HW are sparse, including a few studies with limited sample sizes and variable response rates. Larger studies, based on home sleep tests or new validated digital tools, such as smartwatches, smart pillows, and microphones, are warranted.

BACKGROUND:Variant-adapted vaccines are recommended in vulnerable populations to address the waning immunity and the emergence of immune-escaping SARS-CoV-2 variants, yet data about immune responses to such vaccines in people living with HIV (PLWH) are limited. We therefore aimed to assess long-term immune responses to an original-BA.4/5 mRNA booster in this population. METHODS:In this prospective longitudinal study, PLWH receiving either an original-BA.4/5 bivalent booster or an original monovalent booster and HIV-negative healthcare workers (HCWs) receiving a bivalent booster were enrolled and sampled before (T0), 1 month (T1), and 4-9 months (T2) after the vaccine administration. SARS-CoV-2-specific T and B cells, RBD-binding antibodies, and RBD-blocking antibodies against both wild type (WT) and omicron BA.4/5 virus were determined. RESULTS:The bivalent booster is able to transiently increase both humoral and polyfunctional T cell responses in PLWH, with humoral responses comparable to those observed in HCWs. While T cell responses are cross-reactive against viral variants and stable over time, humoral immunity is imprinted to the ancestral virus and wanes quickly. Furthermore, whilst previous SARS-CoV-2 infection does not affect the trajectory of vaccine-elicited immune responses, markers of HIV-related T cell dysfunction are associated with lower antibody peak responses and higher antibody waning. Lastly, the bivalent booster was superior to the monovalent one in inducing BA.4/5-reactive RBD-blocking antibodies. CONCLUSIONS:The original-BA.4/5 bivalent booster is highly immunogenic in PLWH and superior to the monovalent one in inducing humoral responses against the BA.4/5 virus, although HIV-related T cell dysfunction markers are associated with blunted and less durable antibody immunity.

Background/Objectives: This retrospective multicenter study, conducted within the ORCHESTRA Project, investigated SARS-CoV-2 reinfections among 5777 healthcare workers (HCWs) from four University Hospitals (Modena, Verona, Padova and Trieste) in northern Italy, aiming to assess the risk of reinfection and its determinants, comparing the clinical characteristics of reinfections with those of first infections, and examining the impact of preventive measures and vaccination strategies. Methods: HCWs completed an online questionnaire between June and August 2022. The survey collected demographic, occupational, and clinical data, including information on first infections and reinfections. Statistical analyses were performed using SPSS 28.0, through bivariate and multivariate approaches. Results: Response rates were 41.8% for Modena, 39.5% for Verona, 17.9% for Padova, and 17.4% for Trieste. Among the respondents, 4.8% (n = 276) experienced 2 infections and 0.5% (n = 27) reported 3 infections, out of a total of 330 reinfection cases. Additionally, 43.0% (n = 2787) reported only one infection, while 51.5% were never infected. Reinfection rates increased across five study phases (based on the epidemiological context), likely due to the emergence of new SARS-CoV-2 variants. A booster vaccine dose significantly reduced reinfection risk. Higher reinfection risk was found among HCWs aged ≤30 years, those with chronic respiratory diseases, and those working in COVID-19 wards, particularly nurses and allied health professionals. Reinfections were associated with a lower frequency of symptoms both during the period of swab positivity and after a negative swab, as well as with a shorter duration of swab positivity. No significant differences in symptom duration were found between first infections and reinfections. Conclusions: Despite its limitations, the online questionnaire proved a useful tool. Natural infection and vaccination reduced both reinfection risk and symptom severity. Prior infections should be considered in planning vaccination schedules and prioritizing HCWs.

Background/Objectives: This study examines the longitudinal dynamics of anti-nucleocapsid (anti-N) and anti-spike (anti-S) antibody responses to SARS-CoV-2 infection and mRNA vaccination based on 81,878 serum samples from 23,616 healthcare workers (HCWs) across five European countries. It includes data across four scheduled vaccine doses-predominantly BNT162b2-with 25% of samples originating from individuals with confirmed prior infection, as evidenced by elevated anti-S levels, positive Anti-N antibodies, or PCR results. Methods: The study employed a shifted transformation method for data normalization and utilized the Bass diffusion model to predict antibody titer dynamics influenced by both internal factors-such as immune activation contextualized through sociodemographic issues-and external factors, including infection and vaccination. Despite the absence of direct measurements for some internal variables, the model effectively inferred their impact, enabling a rigorous and nuanced delineation of immune response profiles. Results: The Bass diffusion model rigorously captured variations in antibody titers, analyzed through demographic factors such as gender, age, and job role, while thoroughly accounting for pre-infection status. The results indicate that Anti-N antibodies, exclusively produced post-infection, exhibited a rapid decline, while anti-S antibodies, generated from both infection and vaccination, demonstrated prolonged persistence. A significant decline in anti-S levels was observed 3-5 months post-vaccination, with adaptive immunity-characterized by the dominance of internal factors effects relative to external ones-achieved in most groups after the fourth dose. However, adaptive immunity post second dose was limited to specific demographics. Conclusions: These findings emphasize the significance of the Bass Method in predicting vaccine-induced, hybrid immune responses and detecting adaptive immunity by overcoming limitations in internal factor data, thereby advancing effective vaccination and infection control strategies during public health crises. These findings highlight the Bass Method's value in predicting vaccine-induced and hybrid immunity, effectively addressing internal factor data gaps to enhance vaccination and infection control strategies.

IntroductionThe long-term dynamics of T-cell immunity following SARS-CoV-2 vaccination, essential for durable protection, remain incompletely understood. This study, therefore, aimed to investigate the kinetics and persistence of spike-specific T-cell responses in vaccinated healthcare workers.MethodsWithin the framework of the ORCHESTRA Project, we conducted a longitudinal study on the kinetics and persistence of CD4+ and CD8+ T cell immunity in healthcare workers (n=305) from four hospitals and public health centers across two European countries who received either 2 or 3 doses of an mRNA vaccine, with or without prior SARS-CoV-2 infection. Specifically, the anti-spike adaptive immune cellular response was evaluated, focusing on its crosstalk with the B cell response as measured by serology. Circulating cellular adaptive immune cells were extensively analyzed using flow cytometry to assess pro-inflammatory cytokine production (TNF-α, IFN-γ, IL-2), functional activation (CD154), and memory differentiation (CD45RO).ResultsOur findings show that anti-spike T cell reactivity is not influenced by age, with the only exception of a weak positive correlation with spike-specific CD8+CD45RO+ T lymphocytes (Spearman’s rho = 0.34, p<0.001), and an equally weak negative correlation with CD8+TNF+ (Spearman’s rho = -0.23, p<0.01). Other variables, such as gender and job category, did not significantly impact the vaccine-induced, anti-spike T cell immune response.DiscussionNo distinct relationship between CD4+ and CD8+ T cell subsets was observed post-vaccination. However, specific dynamic changes in vaccine-induced T cells were identified showing clear dose- and time-dependence. Finally, the median level of CD8+CD154+ lymphocytes, indicative of activated T cells, was significantly associated with infection incidence and may represent a reliable predictive biomarker. This study provides evidence that the vaccine-induced anti-spike cellular immune response should be considered when making vaccination decisions, as it has predictive value for infection risk.

Background The prevalence of obesity is increasing all over the world, resulting in a global health emergency. The impact of obesity on the risk of SARS-CoV-2 infection and symptom severity, especially among high-risk working populations such as health workers, deserves further studies. Methods A multicentric retrospective cohort study was conducted among health workers at four Italian University Hospitals belonging to the ORCHESTRA Project. Data were collected through an online survey, investigating sociodemographic and clinical data, until September 2022. Results The questionnaire was filled out by 5777 health workers. The median age was 46 years old (I-III quartile 20-72) and 75.5% were females. Data on BMI was available for 5470 participants. Overweight and obese subjects amounted to 23.4% and 9.8%, respectively. Naïve health workers were the majority (57.4%). Overweight and obese subjects were at a higher risk of infection only before vaccination with respect to normoweight subjects (RRR = 1.28 (IC 95% 1.01-1.62, p = 0.039) and 1.36 (1.00-1.86, p = 0.047), respectively). Major acute and post-acute COVID-19 symptoms were more common among obese subjects, as compared to those with a normal weight (35.2% vs. 23.5%, and 14.2% vs. 9.3%). BMI did not reduce antibody levels after vaccination. On the contrary, overweight and obese health workers had a significantly higher RGM after the third dose (1.12 and 1.48, respectively; normal weight as reference). Conclusions Overweight and obese subjects are at a higher risk of SARS-CoV-2 infection. However, SARS-CoV-2 vaccination fosters a high antibody response even in these individuals. Vaccination against SARS-CoV-2 should be prioritized in subjects with a high BMI, especially in highly exposed workers, such as health workers.

Purpose Anti SARS-CoV-2 vaccination initially showed high effectiveness in preventing COVID-19. However, after the surge of variants of concern, the effectiveness dropped. Several studies investigated if this was related to the decrease of the humoral response over time; however, this issue is still unclear. The aim of this study was to understand whether SARS-CoV-2 anti-S IgG levels can be used to predict breakthrough infection risk and define the timing for further booster doses administration. Method Within the framework of the ORCHESTRA Project, over 20,000 health workers from 11 European centers were enrolled since December 2020. We performed two Cox proportional hazards survival analyses regarding pre-Omicron (from January to July 2021) and Omicron (December 2021–May 2022) periods. The serological response was classified as high (above the 75th percentile), medium (25th-75th), or low (< 25th). Results Seventy-four (0.33%) and 2122 (20%) health workers were infected during the first and second periods, respectively. Both Cox analyses showed that having high anti-S titer was linked to a significantly lower risk of infection as compared to having medium serological response [HR of high vs medium anti-S titer = 0.27 (95% CI 0.11–0.66) during the first phase, HR = 0.76 (95% CI 0.62–0.93) during the second phase]. Conclusion Vaccine effectiveness wanes significantly after new variants surge, making anti-S titer unsuitable to predict optimal timing for further booster dose administration. Studies on other immunological indicators, such as cellular immunity, are therefore needed to better understand the mechanisms and duration of protection against breakthrough infection risk.

Abstract Introduction Vaccination is effective against SARS-CoV-2 infection. However, the role of anti-S IgG (AS) in preventing infection is still unclear. Aim of this study was to understand whether health workers (HW) with high AS titers sustained a lower risk of infection across the Omicron variant (OV) period. Methods Within the framework of the ORCHESTRA European project, 3,565 HW from Padova and Verona cohorts, who had at least one AS titration after booster dose, were included. A stratified survival analysis was performed, considering as infected by OV those HW with a positive RT-PCR test between December 2021 and June 2022. Results Older age groups (40-49 Hazard Ratio=0.76; CI: 0.64-0.91; p=0.003; 50-59 HR=0.79; CI: 0.67-0.95; p=0.009; >60 HR=0.75; CI: 0.59-0.96, p=0.02) had a lower risk of infection. Previous infected HW had a diminished risk too, although only infections before the first dose reached significance (HR=0.70; CI: 0.54-0.89; p=0.004). The risk reduction was about 18% among HW who had antibody titer above the 80th percentile (HR=0.82; CI 0.71-0.95; p=0.007). Discussion Our data showed that older and previously infected HW sustained lower risk of infection during the OV wave. The scant research on AS titer role against OV shows that higher AS levels ensure stronger protection. Our study seems to support these findings. However, this effect is limited and not usable to exclude from further booster doses the HW with high antibody titers. Conclusion High AS titer against SARS-CoV-2 showed a protective, albeit mild, role against infection across OV period.

Abstract Introduction The stoma creation is often a life-saving procedure but also a life-changing experience, with potential negative impact on the workability. This review aimed to summarise current literature about the impact of enterostomy on working life, attempting to provide benchmarks for clinical practice. Methods According to WHO and PRISMA guidelines, original articles between January 2012 and April 2023 were searched in PubMed, Scopus, and Web of Science, using the following keywords: work performance, work-ability, working capacity, capacity to work, fitness for work, enterostomy, surgical stomas. Results Starting from 3,954 titles, 13 articles were finally included. The main findings are related to aspect concerning ostomy awareness and related complications, limitations at workplace and restriction in daily working activities, and job resumption. Work and social function of these were influenced by gender, education, hope, and skills. Some interesting reported aspect are sex-related. Discussion Workers needing an ostomy are increasing with an improving of associated problems related to three main aspects: inability to do “heavy” work; need to change the aid during working hours; change the toilets. No studies are available that have investigated the definition of possible contraindications in work tasks for enterostomy users, or, more generally, reasonable accommodation of the workplace for the individual with an enterostomy. Conclusion This review attempted to comprehensively summarise the current information on the impact of ostomy on work-ability, trying to give some practal implication on the topic. Further exploration of these aspects is necessary to facilitate the reintegration of individuals with enterostomies into work, and reduce social inequalities.

Abstract Introduction The increasing number of healthcare workers (HCWs) occupationally exposed to ionizing radiation (IR) and the growing number of cancer disease survivors in the working age, require adopting shared and sustainable management models to protect workers’ health and safety. Methods We performed a retrospective analysis of health surveillance activities carried out in the last six years on HCWs working at the University Hospital of Verona. All cancer cases were collected and evaluated, as well as information on the characteristics of the worker and job task. The cases were then appraised and compared with the most recent evidence in the literature. Results Ten cancer cases were recognised: four breast cancer, one gastric lymphoma, two papillary thyroid carcinomas, one melanoma, two leukemia cases and one colon cancer. For eight workers, it was necessary to appraise the probability of causation regarding occupational IR exposure and the onset of the disease, as well as fitness for work, which in more than 50% of the cases led to restrictions. Discussion The case series analysis enabled to identify a tailor-made health surveillance protocol for these IR- exposed workers and to facilitate the support of a team of referral physicians so that the worker was quickly taken care of. The literature review revealed insufficient scientific evidence to support the occupational physician in managing these cases. Conclusion The management of cancer workers exposed to IR requires a close multidisciplinary collaboration, in order to take care of both their health and safety protection needs and their professionalism at work.

Abstract Introduction Health promotion (HP) is an important goal of Occupational Medicine. Workplace interventions showed their effectiveness in improving employees’ health. However, studies on health workers (HW) are few and limited, involving small groups. The aim of this research was to evaluate the usefulness of HP programs (HPP) in a large University Hospital. Methods In 2020, two online screening questionnaires were addressed to the over 4,900 HW belonging to the University Hospital of Verona. Salt consumption (SC) was assessed through MINISAL questionnaire, while the risk of sleep apnea (SA) was evaluated through STOP-BANG. HW at high risk for high SC were invited to an individual counseling session and a 6-month follow-up, while polygraphy was offered to HW at high risk for SA. Results MINISAL and STOP-BANG were filled out by 34% and 31% of the study population. In particular, 350 were included in the high SC category and 212 in the high risk for SA. Follow-up examinations were performed in 95 HW; 83% showed a reduction in SC. Polygraphy was performed in 64 HW; 69% were diagnosed with SA and a pulmonological examination was therefore recommended. Discussion The prevalence of HW at high risk for high SC or SA was low, as compared to the general population. The percentage of HW participating in HP programs and the adherence to counseling recommendations were good, showing a high awareness among HW. Conclusion Our studies confirmed the effectiveness of HPP among HW. Screening questionnaires are low-cost and easy-to-perform tools, very useful in involving large working populations.

We compared SARS-CoV-2 positivity between the foreign-born adult working population and Italians living in the Verona area to investigate whether being a foreign-born adult could confer an increased risk of infection or lead to a diagnostic delay. The present study included 105,774 subjects, aged 18–65 years, tested for SARS-CoV-2 by nasopharyngeal swabs and analyzed at the University Hospital of Verona between January 2020 and September 2022. A logistic regression model was used, controlling for gender, age, time of sampling, and source of referral. A higher proportion of SARS-CoV-2 positivity in Italian (30.09%) than in foreign-born (25.61%) adults was reported, with a higher proportion of SARS-CoV-2 positivity in men than women in both cohorts analyzed. The difference in swab positivity among Italian and foreign-born adults was the highest in people aged 18–29 years (31.5% vs. 23.3%) and tended to disappear thereafter. Swab positivity became comparable between Italian and foreign-born adults during the vaccination campaign. Multivariable analysis confirmed the lower risk of swab positivity among foreign-born adults (OR = 0.85, 95% CI 0.82–0.89). In the Verona area, foreign-born adults showed a lower rate of SARS-CoV-2 positivity than the native population, likely because of underdiagnosis. Hence, public health should increase attention toward these particularly vulnerable populations.

People living with HIV (PLWH) despite having an appreciable depletion of CD4+ T-cells show a good severe acute respiratory syndrome coronavirus 2 vaccination response. The underlying mechanism(s) are currently not understood. We studied serological and polyfunctional T-cell responses in PLWH receiving anti-retroviral therapy stratified on CD4+ counts as PLWH-high (CD4 ≥ 500 cells/mm3) and PLWH-low (<500 cells/mm3). Responses were assessed longitudinally before the first vaccination (T0), 1-month after the first dose (T1), 3-months (T2), and 6-months (T3) after the second dose. Expectedly, both PLWH-high and -low groups developed similar serological responses after T2, which were also non-significantly different from age and vaccination-matched HIV-negative controls at T3. The immunoglobulin G titers were also protective showing a good correlation with angiotensin-converting enzyme 2-neutralizations (R = 0.628, p = 0.005). While surface and intracellular activation analysis showed no significant difference at T3 between PLWH and controls in activated CD4+CD154+ and CD4+ memory T-cells, spike-specific CD4+ polyfunctional cytokine expression analysis showed that PLWH preferentially express interleukin (IL)-2 (p < 0.001) and controls, interferon-γ (p = 0.017). CD4+ T-cell counts negatively correlated with IL-2-expressing CD4+ T-cells including CD4+ memory T-cells (Spearman ρ: -0.85 and -0.80, respectively; p < 0.001). Our results suggest that the durable serological and CD4+ T-cell responses developing in vaccinated PLWH are associated with IL-2-mediated CD4+ T-cell activation that likely compensates for CD4+ T-cell depletion in PLWH.

Abstract Introduction The impact of long-COVID-19 syndrome is still debated, being potentially influenced by residual confounders. This study investigated prevalence of long-COVID-19 symptoms among health care workers (HCWS) of four university hospitals from North-Eastern Italy: Trieste, Padua, Verona and Modena-Reggio Emilia. Methods During June 2022- August 2022, HCWs were surveyed on past COVID-19 infections, medical history and any persisting symptoms. Presence of any post-covid-19 symptoms at 30-60 days or 60+ days since recovery from acute COVID-19 was investigated by multivariable logistic regression. Results were expressed as adjusted odds ratio (aOR) with 95% confidence interval (95%CI). Results 5,432 HCWs returned the questionnaire; 2,387 were SARS-CoV-2 infected at least once, 230 two and 8 three times. Prevalence of long-COVID-19 after the first COVID-19 infection was 24.0% at 30-60 days versus 16.3% at 60+ days, and 10.5% against 5.5% after the second SARS-CoV-2 event, respectively. The most frequent post-COVID-19 symptoms were general (35.1%), ENT (21.8%) or pulmonary (21.0%), whereas symptoms persisting after recovery from acute disease were predominantly neurological (50.3%), general (40.9%) and psychological (40.9%). The main determinants of long-COVID-19 syndrome at 30-60 days were Alpha predominant transmission period (aOR=4.34; 3.25-5.79)), COVID-19 associated hospitalization (aOR= 3.14; 2.17-4.54)) or female sex (aOR=1.88; 1.18-2.98), followed by age>40, non-Caucasian race or BMI>25 or <18. Discussion Prevalence of long-COVID-19 was higher during the initial stages of the pandemic, when more virulent viral strains were circulating and vaccination were not available. Conclusions The risk of long-COVID-19 likely decreased inversely with herd immunity level. The high prevalence of persisting psychological/neurological symptoms questions possible predisposing factors to Long-COVID-19.

Abstract Introduction SARS-CoV-2 had enormous impact on occupational health, particularly in healthcare. In Italy, nearly 500,000 health workers (HW) were infected. Key questions to be addressed by occupational medicine, e.g. relationship between humoral and cellular immunity, impact of breakthrough infections, comorbidities, variants of concerns (VoC), long COVID, compensation, targeted risk assessment and health surveillance. Methods Considerations from literature and data from the European ORCHESTRA multicentric study involving about 63,500 HW from 14 European countries with > 50 papers published. Results Vaccines contained the pandemic, even though breakthrough infections (cumulative incidence < 1.5% in fully vaccinated HW, 20.6% in boosted) and reinfections occurred, mainly due to VoC and to some determinants, including comorbidity and immunological status. At least 65 million individuals worldwide are estimated to have long COVID, occurring in at least 10% of SARS-CoV-2 infections, with >200 symptoms/signs. The study of immune response is still crucial. Humoral response is relevant in > 99.3% of vaccinated HW, with decreasing temporal trends related to age, previous infections, and vaccine type. Little is known about cellular immunity and its interaction with humoral response, currently under study on about 300 HW. Conclusions In occupational settings, risk assessment and health surveillance protocols should consider the risk factors for breakthrough and reinfections and risk profiles for vulnerable workers with comorbidities and predisposing factors for long COVID. Vaccine campaigns should be concurrent with ‘flu vaccine; health surveillance program should consider return-to-work policies; compensation criteria for occupationally infected workers should be harmonized.

OBJECTIVES:occupational exposure to vapours, gases, dusts and fumes (VGDF) plays an important role in the development and exacerbation of respiratory diseases. The aim of this study is to evaluate the possible association of occupational exposure to airborne pollutants and chronic respiratory diseases. DESIGN:multicase-control study. SETTING AND PARTICIPANTS:cases of chronic respiratory diseases and controls from the Italian multicentric study Gene Environment Interaction in Respiratory Diseases (GEIRD). MAIN OUTCOME MEASURES:the occurrence of rhinitis, asthma, chronic bronchitis/chronic obstructive pulmonary disease (COPD), asthma severity, spirometry data, exhaled nitric oxide (FeNO) were examined in relation to chronic and acute occupational exposures to airborne pollutants using multiple regression models. RESULTS:2,943 subjects were enrolled in the study. Regularm exposure to VGDF was associated with a higher prevalence of chronic bronchitis/COPD (OR 1.40, 95%CI 0.98-1.99), especially in those also having asthma (OR 1.80, 95%CI 1.14-2.85), a lower prevalence of remittent asthma (OR 0.53, 95%CI 0.29-0.96) and, in those with asthma, an increased activity of the disease (severity score) (OR 1.77, 95%CI 1.20-2.60). No associations were observed between occupational exposure and prevalence of rhinitis, spirometry and FeNO data. Finally, an association was found between acute exposure to airborne pollutants (occupational and non-occupational) and the respiratory diseases investigated, in particular active asthma and asthma associated chronic bronchitis/BPCO. CONCLUSIONS:these data confirm a significant role of occupational exposure to airborne pollutants on respiratory health, underlying the importance of workplace exposure prevention, in particular for more susceptible subjects, as those with respiratory diseases.

Background: Fractional exhaled nitric oxide (FeNO) is a biomarker of type-2 lung inflammation. Previous studies reported an association between particulate matter (PM) exposure and FeNO, while the association with ambient air temperature is unclear. Aim: To evaluate the short-term association of PM10 concentrations and air temperature with FeNO among subjects with/without chronic respiratory diseases. Methods: 605 healthy controls and 412 cases (rhinitis, asthma, chronic bronchitis) aged 20-70 years, who participated in the GEIRD multicenter case-control study on respiratory health in Verona between 2008 and 2014 were involved. Residential addresses collected during clinical interviews were geocoded, and daily PM10 concentrations and air temperature were assigned at each location in the frame of the BIGEPI project. Mean PM10 concentrations and air temperature were calculated for lag 0-1 days before FeNO measurement and considered short-term exposure indicators in the analysis. Associations were assessed using multiple linear regression of FeNO adjusted for sex, age, case-control status, BMI, smoking, atopy, and seasonality (quadratic function of day of the year). Results: Mean±SD PM10 concentration and temperature were 38.5±18.6 μg/m3 and 14.0±7.7 °C, respectively. FeNO levels were higher for both cases and controls during spring/summer (p<0.001). A 10 μg/m3 increase in PM10 concentrations was associated with a 3% increase in FeNO at lag 0-1 (RR: 1.03, 95%CI:1.00-1.06); no significant association was found with air temperature (RR: 0.88, 95%CI: 0.76-1.02 per 10 °C). Conclusion: Seasonality and PM10 concentrations at the time of measurement seem to influence FeNO levels.