Characteristics and outcomes of vaccinated and nonvaccinated patients hospitalized in a single Italian hub for COVID-19 during the Delta and Omicron waves in Northern Italy.

OBJECTIVE: We compared the characteristics and outcomes of vaccinated and nonvaccinated patients hospitalized with COVID-19. DESIGN: We analyzed patients hospitalized in a COVID hub during three one-month periods: (i) October 15, 2020-November 15, 2020 (prevaccination peak); (ii) October 15, 2021-November 15, 2021 (Delta wave); (iii) December 15, 2021-January 15, 2022 (Omicron wave). To define the epidemiologic context, SARS-CoV-2 infection in healthcare workers was analyzed. RESULTS: SARS-CoV-2 infection incidence in healthcare workers was 146 cases per 1000 persons in 2020 (prevaccination) and 67 in 2021 (postvaccination, when the Omicron variant caused most infections). There were 420 hospitalized patients in the prevaccination period, 51 during the Delta wave (52.1% vaccinated) and 165 during the Omicron wave (52.9% vaccinated). During the Delta wave, a significantly higher number of nonvaccinated (29.2%) than vaccinated patients (3.7%) were admitted to the intensive care unit (ICU) (p = 0.019). Nonvaccinated patients were younger and had a lower rate of concomitant medical conditions (53.2% vs 83.7%; p < 0.001) during the Omicron wave when 80% of patients admitted to ICU and all those who died were still infected by the Delta variant. CONCLUSIONS: Vaccine effectiveness in fragile individuals appears to be lower because of a faster immunity decline. However, the Omicron variant seems to cause less severe COVID-19.

SARS-CoV-2 vaccine breakthrough infections with the alpha variant are asymptomatic or mildly symptomatic among health care workers.

Vaccine breakthrough SARS-CoV-2 infection has been monitored in 3720 healthcare workers receiving 2 doses of BNT162b2. SARS-CoV-2 infection is detected in 33 subjects, with a 100-day cumulative incidence of 0.93%. Vaccine protection against acquisition of SARS-CoV-2 infection is 83% (95%CI: 58-93%) in the overall population and 93% (95%CI: 69-99%) in SARS-CoV-2-experienced subjects, when compared with a non-vaccinated control group from the same Institution, in which SARS-CoV-2 infection occurs in 20/346 subjects (100-day cumulative incidence: 5.78%). The infection is symptomatic in 16 (48%) vaccinated subjects vs 17 (85%) controls (p = 0.01). All analyzed patients, in whom the amount of viral RNA was sufficient for genome sequencing, results infected by the alpha variant. Antibody and T-cell responses are not reduced in subjects with breakthrough infection. Evidence of virus transmission, determined by contact tracing, is observed in two (6.1%) cases. This real-world data support the protective effect of BNT162b2 vaccine. A triple antigenic exposure, such as two-dose vaccine schedule in experienced subjects, may confer a higher protection.

[Update on the subject of epidemiology of blood-transmitted occupational infections]. / Aggiornamenti in tema di epidemiologia delle malattie infettive occupazionali trasmesse per via ematica.

Healthcare workers (HCW) are exposed to many different pathogens, and cases of occupational infection have been reported involving the vast majority of known and emerging agents. The risk is present during all the phases of patient care and manipulation of biologic materials, and the implementation of Standard Precautions--and biosafety level 2 measures in the laboratory--and Transmission-Based Precautions in all health settings represents the necessary preventive intervention required by law. Percutaneous exposures represent an extremely frequent event in healthcare facilities; among the many pathogens acquired through this type of exposure, those of highest concern due to the frequency of exposure are HIV, HBV and HCV. Over the last 10 years, though the risk of exposure is still not negligible, occupational infection with HBV has become a rare event; conversely, the incidence of acute C hepatitis became significantly higher among HCW (1,6 per 100.000 inhabitants) with respect to the general population (0,6), with a seroconversion rate following an occupational exposure between 0,5% and 1,8%; finally, reports of occupational HIV infection have decreased, probably also as a secondary beneficial effect of antiretroviral treatment in patients and post-exposure prophylaxis in HCW. The Studio Italiano Rischio Occupazionale da HIV (SIROH) documented from 1986 to 2009 one occupational HBV case, 6 HIV cases (the last one in 2007) and 32 HCV cases. In Europe, the Directive 2010/32/EU approved on May 10 2010 requires Member State to implement within three years a global strategy to prevent occupational exposures in the healthcare setting, particularly with respect to needlestick and sharp injuries, including the adoption, based on risk assessment, of devices incorporating safety features. In Italy the introduction of these devices, according to data collected by the SIROH, showed the possibility to decrease percutaneous exposures by 75%, an effect sustained over time if supported by information, education and training.

[Tuberculosis risk assessment in Italian healthcare centres]. / La valutazione del rischio tubercolosi nelle strutture sanitarie.

BACKGROUND: Tuberculosis transmission is a significant hazard in healthcare settings. METHODS: Risk factors suggested by CDC guidelines in 1994, which were adopted by the Italian Ministry of Health, were assessed in 29 centres via questionnaires in 2005. RESULTS: Few centers were equipped with negative pressure, respiratory isolation rooms. Half of the centres had high or ongoing risk. CONCLUSIONS: The hazard is underestimated mostly because of a high number of initially undiagnosed TB patients.

[Accidents with risk of blood-borne infections in obstetricians: analysis of a hospital case records]. / Infortuni a rischio di malattie a trasmissione ematica nel personale ostetrico: analisi di una casistica ospedaliera.

BACKGROUND: Health care workers (HCW) are at high risk of accidental contact with biological fluids. In spite of extensive recom mendations concerning HCW accidents continue to be frequent and seem to be related to specific factors. OBJECTIVES: To evaluate the factors influencing risk of blood-borne infections in a particular category of HCW--obstetricians, and obtain information useful for prevention guidelines. METHODS: Data were obtained from the exposure registers of nursing and of the Emergency Ward staff where HCWfirst report after accidental contact with biological fluids. RESULTS: Accidents with risk of blood-borne diseases were more frequent in obstetricians with lower job seniority. They usually occurred between 8 a.m. and 4p. m., in the patient's room. The hands and face (particularly the eyes) were the body parts more often involved In almost half of the accidents, the worker was not wearing any personal protective device. Although some contacts were with infected blood, no seroconversion occurred. CONCLUSIONS: Obstetricians are at high risk of contact with biologicalfluids. Prevention requires a global strategy including the availability of protective and safety devices, as well as worker education, especially concerning the use of such devices, the application of the universal rules of prevention and the improvement of risk awareness. An adequate post-exposure management of accidents in also required