COVID-19 outbreaks in hospital workers during the first COVID-19 wave.

BACKGROUND: Health care workers (HCWs) are on the frontline, playing a crucial role in the prevention of infection and treatment of patients. AIMS: This study was aimed to evaluate the prevalence of hospital-acquired coronavirus disease 2019 (COVID-19) infection at work and related factors at the University Hospital of Trieste workers exposed to COVID-19 patients. METHODS: From March 1 to May 31, of 4216 employees, 963 were in contact with COVID-19 patients or colleagues and were followed up. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in nasopharyngeal swabs was determined every 3 days, by RT-PCR. RESULTS: During the follow-up period, 193 workers were positive for COVID-19 (5%), and 165 of these (86%) were symptomatic. We identified five major cluster outbreaks of COVID-19 infection in Trieste Hospitals, four of which occurred before the implementation of universal masking for HCWs and patients (1-14 March 2020). COVID-19 infection was significantly higher in high-risk ward workers (Infectious Diseases, and Geriatric and Emergency Medicine, odds ratio [OR] 13.4; 95% confidence interval [CI] 5.8-31), in subjects with symptoms (OR 5.4; 95% CI 2.9-10) and in those with contacts with COVID-19 patients and colleagues (OR 2.23; 95% CI 1.01-4.9). CONCLUSIONS: Hospital workers were commonly infected due to contact with COVID-19 patients and colleagues, mainly in the first 15 days of the pandemic, before the implementation of universal mask wearing of HCWs and patients. Repetitive testing and follow-up permitted the identification of COVID-19 cases before symptom onset, obtaining better infection prevention and control.

Preliminary data on the neurophysiological evaluation of male sexual dysfunction in patients with pelvic ring fractures: a multicenter retrospective study.

OBJECTIVE: Traumatic pelvic ring fractures include several comorbidities due to the close anatomical relationship between the skeletal system, pelvic organs, and neurovascular structures. In this retrospective multicenter study, we evaluated patients complaining of sexual dysfunction following pelvic ring fractures, assessed through different neuro-physiological examinations. PATIENTS AND METHODS: Patients were enrolled one year after the injury according to their reported ASEX scores and evaluated on the basis of the Tile's type of pelvic fracture. Lower limb and sacral somatosensory evoked potentials, pelvic floor electromyography, bulbocavernosus reflex and pelvic floor motor evoked potentials were recorded, according to the neurophysiological indications. RESULTS: A total of 14 male patients (mean age 50.4; 8 subjects Tile-type B and 6 Tile-type C) were enrolled. The ages between the Tile B group and the Tile C group of patients were not significantly different (p=0.187), while the ASEX scores were significantly different (p=0.014). In 57% of patients (n=8), no alterations in nerve conduction and/or pelvic floor neuromuscular responses were found. In 6 patients, electromyographic signs of denervation were revealed (2 patients), and alterations of the sacral efferent nerve component were detected in 4 patients. CONCLUSIONS: Sexual dysfunctions after a traumatic pelvic ring fracture are more common in Tile-type B. Our preliminary data did not reveal a significant association with neurogenic aetiology. Other causes could explain the complaining impairments.

[Approach to the assessment of occupational stress at a hospital]. / Approccio alla valutazione dello stress lavoro-correlato in un'Azienda Sanitaria.

In the health sector, the theme of work-related stress is a major issue, representing a significant risk factor on health-care providers which can also affect the quality of health services provided. It is therefore important to adopt a multidimensional evaluation system of work-related stress in order to integrate the results of the analysis of objective and subjective stress indicators. The adoption of a multidimensional validated tool as the one proposed by Inail, allows an integrated analysis of sentinel indicators, objective factors of context and content jointly to direct analysis of the subjective perception of workers through the analysis of the Management Standards developed by Health and Safety Executive. The comparison between three Healthcare Districts, three Mental Health Centers and Administrative Offices of an Healthcare Organization (652 workers involved) revealed the most critical areas which need urgent improvement intervention.

[Freedom from smoking for health care workers. A project from Trieste]. / Operatori della sanità liberi dal fumo. Attivazione di un progetto in Provincia di Trieste.

A tree years interventional study to modify smoking habits in health workers in Trieste province was planed in the collaboration of occupational health unit and Tobacco's Dependence Study Center. The aim of this paper is refer about preliminary data of the project started in 2007 regarding smoking habits in health workers of the Azienda per i Servizi Sanitari n.1 "Triestina" (ASS1) and the Azienda Ospedaliera Universitaria Ospedali Riuniti di Trieste (AOUTS). The project consist of several actions. i) information about risks and opportunities of project; ii) pursuance of the law 51 L 3/2003; iii) Occupational Health Unit and Tobacco's Dependence Study Center collaboration; iv) follow-up of the subjects that choose the disaccustom program. During occupational medical surveillance we collected the data related to 492 workers, 37% of the cases were smokers (180). The results of test of dependence to smoke (test di Fagestrom) showed an high dependence in 19% and an high motivation to stop smoke (test di Richmond) in 39% of the smokers. More than fifty percent of this subjects gave their adhesion to the disaccustom program.

Discrimination and study of rhythmical brain activities in the alpha band: a neuromagnetic frequency responsiveness test.

In this paper we propose a fast procedure--stimulation paradigm, data analysis, data presentation--that permits the study of frequency selective enhancements or suppressions of the cortical responses in selected frequency windows. These responses can be used to classify the underlying activity. This novel procedure combines, in one single test, multichannel detection, finely frequency scanned stimulation, a paradigm that permits to study the effect of the stimulation on the underlying activity (during the non-stimulated periods intermingled with the burst of stimuli) and a compact presentation to appreciate the whole rate/frequency/topographical dependency of the spectral responses. In particular we applied this procedure to non-invasively study for the first time the frequency responsiveness within the extended alpha band (6 Hz to 14 Hz) under separate visual and somatosensory stimulation. The test proved robust and the responses quite stationary. We discriminated the lower and higher alpha band through their different topographical and frequency responsiveness features and suggested them to be the same sub-bands recently discriminated via cognitive experiments on the basis of their functional correlates. We measured a rate dependent alpha suppression (both in the somatosensory and visual modality) that is suggested to be linked to the decoding of the stimulus rate. A slight decrease in the frequency of the spontaneous activity following stimulations at any rate is suggested to be connected to attentional load. We stressed the importance of our simple sensorial discrimination of those activities already evidenced on the basis of their functional correlates, as well as the possible clinical uses of the test: on epilepsy, Alzheimer's disease (recently described to have effects on the responsiveness of the cortex to sensory stimuli at different frequencies) as well as other disabling pathologies.

Short-term brain 'plasticity' in humans: transient finger representation changes in sensory cortex somatotopy following ischemic anesthesia.

Transient rearrangements of finger representation in primary somatosensory cortex induced by an anesthetic block of the sensory information from adjacent fingers have been shown invasively in animals. Such a phenomenon has been now replicated in seven healthy human volunteers. Somatosensory Evoked Fields (SEFs) have been recorded during separate electrical stimulation of the 1st, 3rd, or 5th finger. Recordings were obtained in control conditions (stage A), following complete ischemic anesthesia of the 4 non-stimulated fingers (stage B), and after regaining sensation (stage C). SEFs were recorded using a 28-channel DC-SQUID magnetometer; a single position of the sensor was enough to identify the source of N20m, P30m and following components using the Equivalent Current Dipole (ECD) model. The amount of afferent input during stages A through C was monitored with surface electrodes placed on the nerve at wrist and elbow. No variation of the nerve compound potential was observed during stages A through C. In stage A, the localizing algorithm was able to discriminate the individual finger representation in accordance with the somatotopic organisation of the sensory homunculus. It was observed that the ECDs responsible for the cortical responses from the unanesthetized finger were significantly changing following a relatively brief period of sensory deprivation from the adjacent fingers. Such changes of the ECDs with respect to the control conditions were characterized by an increase in strength and deepening for the middle finger, and by a shift on the coronal plane for the thumb and the little finger (medial for the former, lateral for the latter). Such changes became progressively evident in stage B, but were persisting in stage C.

Simultaneous motor output and sensory input: cortical interference site resolved in humans via neuromagnetic measurements.

Neuromagnetic measurements were carried out during median nerve stimulation at the wrist in complete relaxation (a) and during active contraction of the hand muscles (b). Firstly, activity of the generator source responsible for the major component of the sensory evoked magnetic fields (SEFs) was mapped and localized during condition (a) and (b). Then the subtraction maps ((a)-(b)) were obtained and the virtual 'dipole' responsible for the 'interference' (less than or equal to SEFs amplitude) between the afferent input and the motor output was tridimensionally localized in a position compatible with the knee and the convexity of the postcentral gyrus.

Magnetic source imaging and reactivity to rhythmical stimulation in tuberous sclerosis.

The present study combined functional magnetoencephalography (MEG) and anatomical magnetic resonance imaging (MRI) information in three patients affected by tuberous sclerosis and partial epilepsy. MEG recordings were performed during both spontaneous and visual evoked activity. The former showed a large variety of complexes whose spatial and temporal distribution suggested different neuronal populations acting simultaneously in the same focal district. When these data were integrated with MRI images (magnetic source imaging, MSI) there was agreement in the definition of tubers and extension of the epileptogenic area. Furthermore, cortical reactivity to rhythmical stimulation was studied with trains of visual stimuli according to a recently proposed frequency responsiveness procedure (FRP). As compared to normal controls, a large 6 Hz activity was observed during the pause after a non-resonant stimulation. This altered resonance property may indicate a disturbed primary sensory processing notwithstanding a preserved associated processing. These results show that neuronal malfunctioning in tuberous sclerosis complex patients may not be restricted to the area of cortical tubers, but can also affect functionally correlated regions.

[Magnetic fields evoked by auditory stimuli: a normative study]. / Campi magnetici evocati da stimoli uditivi: studio normativo.

After outlining the fundamentals of biomagnetism and their possible clinical applications, the authors report the results of a normative study on auditory magnetic fields performed on 18 normally hearing subjects between the ages of 25 and 30. Having presented a thorough review of the literature, they then describe the recording technique employed, the dcSQUID biomagnetic system for signal detection, the shielded room, the characteristics of the stimulus. The auditory magnetic response is characterized by three main waves (P4Om, N100m, P200m) whose latency and amplitude values were calculated. Moreover, in order to localize dipolar activity, certain parameters, such as P and T, were taken into consideration. Localizations were made using a spherical volume conductor or with MRI, which was in any case employed in all the subjects. The waves, especially the N100m recorded contralaterally to the stimulus, showed a reduced latency and an increased amplitude when compared to those recorded ipsilaterally. Moreover, a systematic posterior shift of the N100m source into the left hemisphere with respect to the right one was detected. In conclusion, the authors emphasize the need to study electric as well as magnetic responses in order to better understand auditory cortical functions.

[Respiratory symptoms and occupational sensitization in a group of trainee bakers: results of a 6-month follow up]. / Sintomi respiratori e sensibilizzazioni professionali in un gruppo di allievi panificatori: risultati di un follow-up a 6 mesi.

We investigated the prevalence of atopy by 4 different criteria (personal and family atopy, atopy by prick test and by serum IgE levels), and sensitization to wheat flour and alpha amylase in a group of trainee bakers and in a group of trainee graphic artists as controls (baseline check-up). The follow-up was performed 6 months later only among trainee bakers (90 cases), based on an updating questionnaire and on repeated skin prick test with wheat flour and alpha amylase extracts. Trainee bakers and controls were similar with respect to age, number of smokers, atopy evaluated by 4 different criteria, and detection of serum IgE (RAST) and IgG specific to wheat flour. Positive skin prick test to wheat flour (4%) and alpha amylase (1%) were found only among trainee bakers. At the baseline control 4 students (4.4%) complained of respiratory symptoms when working with wheat flour (WRS). At the six month follow up 6.6% of the trainee bakers complained of WRS: 3.3% had persistent symptoms, 3.3% were new cases and 1.1% had become asymptomatic. Five cases (5.5%) were skin positive to wheat flour or alpha amylase, but only one was unchanged, while 4.4% were new cases and 3.3% turned negative. None of these changes was statistically significant (McNemar test). The trainee bakers complaining of WRS at the baseline or at follow-up (7 cases, when compared with the non-symptomatics, showed a higher prevalence of personal atopy and skin sensitization to occupational allergens; there were no differences, however, with regard to atopy by prick test, IgE levels or the presence of wheat specific IgE and IgG. The trainee bakers skin positive to the occupational allergens (8 cases) showed prevalences of personal atopy and atopy by prick test significantly higher than trainee bakers skin negative to wheat flour or alpha amylase (p < or = 0.01). Evaluating wheat flour specific IgE and IgG in the serum of trainee bakers and controls provided us with more information about the specificity of such tests and suggests caution in attributing the presence of these immunoglobulins in the serum to specific occupational exposure or to specific occupational sensitization. A six-month follow up is likely to be too short an interval to observe significant changes in work-related symptoms and in skin sensitization to occupational allergens. The results, however, emphasize the important role of personal atopy as a predisposing factor in the development of occupational disease among trainee bakers.

[Allergic sensitization and latex-associated symptoms in a group of health workers]. / Sensibilizzazione allergica e sintomi associati al lattice in un gruppo di lavoratori della sanità.

The presence of symptoms connected with the use of latex rubber gloves and sensitization to this allergen was studied in a group of 660 hospital workers who regularly used gloves as a means of protection. Symptoms connected with the use of gloves were reported by 153 subjects (23.2%) and were significantly associated with female subjects length of use and type of medical care. The majority of cases reported irritative symptoms (13.2%) whereas contact dermatitis and rash were reported by 3.6% and 5.5% of cases respectively. Systemic reactions (asthma and/or rhinitis) were reported by 5 subjects. Prick tests for latex were positive in 23 cases (3.5%), 15 of which were symptomatic. Positive skin reaction to latex was significantly associated with family atopy, personal case history and prick test. It is concluded that the presence of symptoms and sensitization to latex requires the implementation of preventive measures in order to reduce the risk of sensitization to a minimum, in addition to removal from exposure of those subjects who are already symptomatic or at risk.

Evidence for a 7- to 9-Hz "sigma" rhythm in the human SII cortex.

Electrical activity of the human brain features several rhythmical components which can be readily studied with whole-scalp neuromagnetometers. We describe a new 7- to 9-Hz "sigma" rhythm in the human second somatosensory cortex, distinct from both the mu rhythm of the primary sensorimotor cortex and the tau rhythm of the supratemporal auditory cortex. Sigma shows rate-selective responsiveness to rhythmical median nerve stimulation and is enhanced by stimulation at the rhythm's dominant frequency. Single stimuli may trigger several periods of the rhythm. The functional significance of the sigma rhythm remains to be investigated.

Sensitization to green coffee beans and work-related allergic symptoms in coffee workers.

BACKGROUND: Occupational respiratory allergy to green coffee beans (GCB) and to castor beans (CB) was studied in 112 workers in a modern coffee manufacturing plant of Trieste (Italy), where the process is completely automatic, the environmental conditions are good and where exposure to CB can be considered absent because since 1970, only new sacks have been used for coffee transportation. METHODS: All subjects were interviewed by a trained doctor using a questionnaire to investigate allergic symptoms and predisposing factors. Sensitization to GCB and to common allergens (pollens, molds, house dust mites) were evaluated by the skin-prick test. The serum of subjects with a positive skin-prick test to CGB or who had symptoms at work was tested for specific IgE (RAST) for GCB and CB. Lung function was evaluated by a Ponigraph spirometer. RESULTS: Sensitization to GCB was found in 25.8% of green coffee workers (31 cases), in 2.7% of roasted coffee workers (37 cases) and in 4.5% of the clerks (44 cases), p < 0.01. The evaluation of IgE specific for CB gave positive results only in 3 of 10 subjects sensitized to GCB. A total of 20% of GCB workers (6 cases) complained of work-related respiratory symptoms (asthma and/or rhinitis) compared with only one subject in the roasted coffee group and one in the control group (p < 0.01). Asthma was reported by 2/31 of the green coffee workers and by 1/44 of roasted coffee workers. CONCLUSIONS: There was a significant correlation between sensitization to GCB and work related symptoms (p < 0.01), common allergic symptoms (p < 0.05) and atopy by prick test (< 0.01). These results point to the need to evaluate atopic status in workers and identify the most susceptible subjects, with the aim of informing them of their at-risk status and monitoring their progress. This makes it possible to diagnose sooner those symptoms possibly indicative of a work-related disease, because even in presence of good environmental conditions and even when symptoms are mild, it is almost always the atopic subjects who are affected.

Analysis of interhemispheric asymmetries of somatosensory evoked magnetic fields to right and left median nerve stimulation.

This paper represents the first neuromagnetic systematic investigation of the asymmetries between the sources activated in the right and left hemispheres after electric median nerve stimulation. We focused our attention on the location and strength of the equivalent sources activated in the primary somatosensory cortex contralateral to the stimulated nerve in the 50 msec post-stimulus epoch. The spatial coordinates of the equivalent sources did not differ statistically significantly in the two hemispheres. Minor individual asymmetries are shown to be related to the interhemispheric differences in the position of the central sulcus as revealed by MRI investigation. The equivalent sources were significantly stronger in the left hemisphere. When comparing the location of the generators across individuals, we show that interhemispheric differences fluctuate less than absolute values. A quantitative evaluation of these findings is also given. Based on these results, a normative data set has been established, to be used as a baseline in following up changes of interhemispheric asymmetries due to hemispheric lesions and subsequent cortical reorganization.

Study of focal epilepsy by multichannel neuromagnetic measurements.

A systematic investigation of several cases of focal epilepsy has been performed in an unshielded environment using a 4-channel neuromagnetic sensor. The localizations provided by the magnetic measurements have been compared with clinical evidence and confirmed by X-ray findings, and in one case also by intracranial surgery. The results show the importance of simultaneous detection of magnetic fields at different sites of the scalp in order to get a dynamic view of the epileptic activity and to detect multifocal activity unsuspected on the basis of the EEG investigation.

Source model and scalp topography of pattern reversal visual evoked potentials to altitudinal stimuli suggest that infoldings of calcarine fissure are not part of VEP generators.

Visual evoked potentials (VEPs) to pattern reversal vertical bar stimuli were recorded from 19 scalp, 2 zygomatic and 3 inion derivations referenced to digitally linked earlobes in 50 controls. 1, 2 and 4 cycles per degree (cpd) patterns were presented as full field (FF) stimuli, on upper and lower hemifields (UHF-LHF), upper and lower quadrants and with the occlusion of central and peripheral UHF and LHF. VEPs to octant stimuli were also recorded with 2 cpd patterns. N1, P1 and N2 components were recorded from posterior and inion derivations with FF stimuli, from posterior derivations with LHF stimuli, only from inion leads with UHF stimuli, from derivations ipsilateral to stimuli with quadrants and octants, and from midline derivations only with lower quadrants. Polarity inverted sequences (iP1-iN1-iP2) were recorded from the other scalp derivations, with similar latency and spatial frequency sensitivity as N1-P1-N2. The orientation of Equivalent Dipoles (ED) was orthogonal with surface coordinates of mesial and occipito-polar calcarine cortex, measured on Magnetic Resonance Imaging. A model of VEP generators is proposed, suggesting that the VEP sequence is elicited only in mesial and occipito-polar surfaces of calcarine cortex.

Visual evoked potentials generator model derived from different spatial frequency stimuli of visual field regions and magnetic resonance imaging coordinates of V1, V2, V3 areas in man.

Visual evoked potentials (VEPs) to pattern reversal vertical bar stimuli were recorded from 24 scalp derivations (including zygomatic and inion) referenced to digitally linked earlobes in 50 controls. 1, 2 and 4 cpd patterns were presented as full field (FF) stimuli, on Upper Hemifields (UHF) and Lower Hemifields (LHF), upper and lower quadrants and with the occlusion of central and peripheral UHF and LHF. VEPs to octant stimuli were also recorded with 2 cpd patterns. N1, P1 and N2 components were recorded from posterior and inion derivations with FF stimuli, from posterior derivations with LHF stimuli, only from inion leads with UHF stimuli, from derivations ipsilateral to stimuli with quadrants and octants, and consistently from midline derivations only with lower quadrants. Polarity inverted sequences (iN1-iP1-iN2) were recorded from the other scalp derivations, with similar latency and spatial frequency sensitivity as N1-P1-N2. Single Equivalent Dipole (ED) calculations were performed on N1 and P1 recorded in the different stimulus conditions. Our findings contradict previous hypotheses on VEP generators and contradict the predictions of VEPs polarity and distribution based on the "cruciform model" of VEPs generators. In order to explain the distribution of VEPs to upper and lower half fields and to quadrant and octants, we propose a model based on the position of the medial and occipito-polar surface of visual cortex in man.

Neuromagnetic topography of photoconvulsive response in man.

The neuromagnetic method was applied to the study of photoconvulsive responses. The identification of specific magnetic field distributions over the scalp was achieved by; (a) a stimulation paradigm consisting of series of trains of flicker stimuli randomly presented to the epileptic patient, after eye closure, to get epileptic responses while avoiding seizures; (b) a novel procedure for data analysis, to select consistent responses. These patterns, when sufficiently stable in time and dipolar in shape, were used for source localization in the usual biomagnetic framework of the equivalent current dipole source representation. The results of this approach suggest that different specific cortical areas are repeatedly and randomly activated, involving mainly the frontal, occipital and temporal areas, often with a hemispheric prevalence.