Protective role of SARS-CoV-2 anti-S IgG against breakthrough infections among European healthcare workers during pre and post-Omicron surge-ORCHESTRA project

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.

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.

Anti-severe acute respiratory syndrome coronavirus-2 adenoviral-vector vaccines trigger subclinical antiplatelet autoimmunity and increase of soluble platelet activation markers

To slow down the coronavirus disease 2019 (COVID-19) pandemic an unequalled vaccination campaign was initiated. Despite proven efficacy and safety, a rare but potentially fatal complication of adenoviral-vector vaccines, called vaccine-induced immune thrombotic thrombocytopenia (VITT), has emerged the pathogenesis of which seems to be related to the development of platelet-activating anti-platelet factor 4 (PF4) antibodies. While a few studies have evaluated the incidence of anti-PF4 positivity in anti-severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccine recipients, to date no studies have assessed whether an antiplatelet immunological response develops and if this associates with platelet and blood clotting activation. We carried out a prospective study in healthy subjects who received the first dose of ChAdOx1 or Ad26.COV2.S or BNT162b2 vaccines to evaluate platelet-specific and non-specific immune response and in vivo platelet activation and blood clotting activation. Individuals receiving ChAdOx1 and, less so, Ad26.COV2.S developed with high frequency auto- or alloantiplatelet antibodies, increased circulating platelet-derived microvesicles and soluble P-selectin associated with mild blood clotting activation. Our study shows that an immunological reaction involving platelets is not uncommon in individuals receiving anti-SARS-CoV-2 vaccination, especially after ChAdOx1 and Ad26.COV2.S, and that it associates with in vivo platelet and blood clotting activation.

[Effects of inorganic lead exposure on the autonomic nervous system and on the variability of heart rate among workers at a battery plant]

Inorganic Lead can cause a toxic effect on Central Nervous System, Peripheral Nervous System and Autonomic Nervous System (ANS). A damage of the ANS can determine an heart rate variability (HRV) reduction. In this study 43 battery workers exposed to inorganic lead with mean PbB = 31.63 microg/dl (DS 14.77 microg/dl) and 35 not exposed subjects underwent to an evaluation of heart rate variability by specific tests. Heart rate variability in the exposed group was, for some tests (lying to standing, lying to standing-standing to lying) reduced compared with not exposed subjects and for other tests (Valsalva manouvre, lying to standing-standing to lying) correlated with PbB and Zinc Protoporphyrin (ZPP), but not with BMI, age and smoking habits. This study, like others conducted on similar populations, suggest an effect of occupational inorganic lead exposure on Autonomic Nervous System and heart rate variability

Blood cadmium concentrations in the general population of Umbria, central Italy

The aims of this study were (a) to assess blood cadmium (B-Cd) concentrations and to establish a tentative reference interval; (b) to identify significant determinants of B-Cd, in a population from Umbria, Central Italy, which was not occupationally exposed to cadmium (Cd). Four hundred and thirty-four healthy blood-donors volunteered to answer a questionnaire and provide a blood sample for B-Cd analysis, which was performed by graphite furnace atomic absorption spectrophotometry. Blood Cd concentrations ranged from non-detectable values, i.e. below 0.1 microgram/l up to 3.4 micrograms/l and were not normally distributed. The median values and the 95th percentiles were 0.7 and 2.0 micrograms/l, respectively. Concentrations of B-Cd were more than double in smokers than in non-smokers, median values being 1.1 micrograms/l and 0.5 microgram/l, respectively. In current smokers, B-Cd values correlated with the number of cigarettes smoked daily (rs = 0.40, P = 0.0001) and with the cumulative exposure to cigarette smoke (rs = 0.35, P = 0.0001). Concentrations of B-Cd correlated with age in the non-smokers, but not in the smokers and were significantly higher in women than in men only in the non-smokers. Both in smokers and non-smokers, B-Cd concentrations were similar in subjects living in urban or in rural areas. In the whole study population the lower and the upper tentative reference limit were < 0.1 and 2.2 micrograms/l, respectively, as computed by a non-parametric rank-based method. The upper limit was approximately double in smokers than in non-smokers (3.1 micrograms/l and 1.6 micrograms/l, respectively). Our results show that B-Cd concentrations in a general population from Umbria are in the range reported for general populations in Northern Italy and other European Countries. Smoking was the strongest determinant of B-Cd concentrations and age had a lesser effect.

[Lead absorption in an Umbrian population from 1982 to 1992]

This report assessed lead absorption in community samples of the general population in Umbria, central Italy, in 1982 and in 1992. Each participant (128 subjects in 1982 and 479 in 1992) answered a questionnaire providing details of personal information and life style. Blood lead levels were determined by atomic absorption spectrophotometry. In 1992 hematocrit and glutamyltranspeptidase (gamma-GT) levels were also measured. In 1982 the mean blood lead level was 226 micrograms/l in males and 167 micrograms/l in females, and in 1992 it was still higher in males than in females (98 micrograms/l vs 61 micrograms/l) as were hematocrit and gamma-GT levels. Multiple regression analysis showed sex and age were the main factors accounting for 42% of the total variation in blood lead levels. They were followed by alcohol consumption, gamma-GT levels and smoking in this order. In conclusion, blood lead levels decreased significantly in central Italy in the decade 1982-92 and persistent lead absorption seems to be due to individual characteristics such as male sex, advanced age and a personal life style which includes alcohol consumption and smoking.

Troleandomycin in the treatment of difficult asthma

BACKGROUND

For difficult asthma, treatment is aimed at improving airway obstruction and minimizing adverse effects of systemic corticosteroids. The combination of troleandomycin (TAO) with methylprednisolone (MP) reportedly has a beneficial steroid-sparing effect on difficult asthma.

METHODS

To test the steroid-sparing effect of TAO, 14 subjects with severe corticosteroid-dependent asthma were studied before and during treatment with MP and TAO.

RESULTS

Treatment with MP and TAO resulted in a clear reduction in respiratory symptoms, asthmatic attacks, corticosteroid and hospitalization requirements, improvement in pulmonary function tests, and a remarkable decrease in peak expiratory flow rate circadian variability when compared with the period before TAO treatment (with corticosteroids). Treatment with MP and TAO was fairly well tolerated. Only a reduction (-5.2%, p < 0.01) in bone mineral content and an increase in plasma glucose levels (from 81.7 to 94.3 mg/dl, p < 0.05) were found, in comparison with pre-TAO values. One subject discontinued MP-TAO treatment because of a mild but persistent increase in serum alanine aminotransferase. In an evaluation of the clinical and pulmonary function test results, eight of the 14 subjects were responders and six were nonresponders. During follow-up three subjects discontinued TAO and consequently had an asthmatic attack after 4, 7, or 15 days, respectively.

CONCLUSIONS

This study confirms that treatment with MP and TAO has a beneficial effect in a subgroup of severely steroid-dependent asthma patients.

Increased lead absorption in children living in an area with high concentration of ceramic workshops

Children who live in contaminated areas or whose cohabitants are occupationally exposed to lead are at a higher risk of lead absorption. The present study examined the blood lead levels of 539 nursery and primary school children living in three towns in the Umbria region (central Italy): Deruta, Corciano and Perugia. Deruta is a small town with a high number of ceramic workshops; Corciano is a mainly agricultural centre; Perugia is the largest town in Umbria. The lead concentrations of house dust, soil, air and water ducts of Deruta and Corciano were also examined. The blood lead levels were significantly increased in children in Deruta (9.7 S.D. = 3.6 micrograms/dL, p < 0.05) and Perugia (9.6 S.D. = 4.0 micrograms/dL, p < 0.05) compared to Corciano (8.3 S.D. = 1.9 micrograms/dL). In Deruta the blood lead levels were higher in children whose cohabitants worked in small ceramic factories or workshops near or in the homes (10.7 S.D. = 4.1 vs 9.0 S.D. = 3.0 micrograms/dL, p < 0.05). The mean concentration of lead in the house dust in Deruta was higher than in Corciano (2.8 S.D. = 2.5 vs 0.8 S.D. = 3.8 micrograms/m2, p < 0.01); the highest values were found in the house dust of the homes of children whose cohabitants worked in small ceramic factories either near or in the same building. There was no significant difference between the concentrations of lead in street dust or tap water of Deruta and Corciano. We conclude that the production of handworked ceramics could lead to an increased risk of lead absorption in children, particularly those who live with workers from this sector.

Monitoring of peak expiratory flow rates during occupational asthma treatment

The purpose of this study was to evaluate the effect of anti-inflammatory drug treatment on respiratory symptoms and lung function in twelve subjects with occupational asthma while at work. PEFR was monitored for four weeks and antiasthmatic drugs (salbutamol, chromolyn sodium and beclomethasone dipropionate) were administered for three weeks, starting after the first week of PEFR monitoring, in an unchanged working environment. After treatment five subjects became asymptomatic, six improved and one continued to have unchanged work-related asthmatic symptoms. There were only minor increases in forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and mean forced expiratory flow during the middle half of FVC (FEF25-75). Bronchial reactivity was studied in eleven subjects: six worsened and five improved. PEFR at 0600 h increased by 9.4% in nine responders and decreased by 5.8% in three non-responders. After treatment diurnal variation (DV) in PEFR decreased by 28.4% in responders and 30.8% in non-responders, even if at the fourth week it was 1.75 higher in non-responders compared to responders. In conclusion, in this study a continuous treatment of occupational asthma with anti-inflammatory drugs minimized respiratory symptoms, slightly increased PEFR and greatly reduced DV in PEFR.

High prevalence of sick building syndrome in a new air-conditioned building in Italy

This study, which was conducted in central Italy, included (a) 525 office workers employed in an air-conditioned building that had fan coil units in every room (building B) and (b) 281 subjects who worked in three naturally ventilated buildings (building A) that were operated by the same public administration. The prevalence of work-related symptoms was assessed by a questionnaire that was administered by an occupational medicine specialist. The most frequent complaints of employees in building B were dry air, strong lighting, and high temperature. Employees who worked in this building experienced a statistically higher prevalence of symptoms that were characteristic of the sick building syndrome. This is the first time that this syndrome has been reported in Italy. Excessive illumination, a low relative humidity, and fiberglass on floors and furniture might have contributed to the symptoms. Inadequate maintenance of the building's air-conditioning plant and the employees' lack of information regarding self-regulation of the fan coil units may also have contributed to the prevalence of symptoms.

An 11-year longitudinal study of the occupational dust exposure and lung function of polyvinyl chloride, cement and asbestos cement factory workers

Standardized questionnaires and lung function tests were administered in 1973, 1980, and 1984 to 126 workers occupationally exposed to polyvinyl chloride (PVC) dust, to cement dust, or to asbestos cement dust until 1974-1978 and to PVC thereafter. The workers in the last group were assigned to two asbestos exposure categories (heavy and slight). The decline in forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1.0) was analyzed with regard to the length of time since the data of first employment. After adjustment for age, height, and smoking status at the date of first employment, the decline in FVC and FEV1.0 among the nonsmokers-light smokers was slightly accelerated with length of employment in the PVC and slight asbestos exposure groups and markedly accelerated with time since first employment in the heavy asbestos exposure group. The heavy smokers in all the exposure groups had FVC and FEV1.0 predicted values that were lower than those of the nonsmokers-light smokers; these differences remained constant with length of employment. Cessation of asbestos exposure for about 10 years did not seem to change lung function decline.