Background: Long COVID is a syndrome characterized by the persistence of SARS-CoV-2 infection symptoms. Among HCWs, prolonged COVID symptoms could lead to the inability to perform work tasks. The aim of this study is to investigate 35-day long-COVID (35-LC) characteristics and risk factors in a one-year period. Methods: We carried out a retrospective cohort study during the COVID-19 pandemic at University Hospital of Bari. A total of 5750 HCWs were tested for close contact with a confirmed case, in the absence of personal protective equipment, or for symptom development. Results: Each positive HCW was investigated for cardiovascular risk factors or respiratory diseases. An amount of 352 HCWs (6.1%) were infected by SARS-CoV-2, and 168 cases evolved to long COVID. The 35-LC group showed mean BMI values higher than the non-35-LC group (25.9 kg/m2 vs. 24.8 kg/m2, respectively), and this difference was significant (p-value: 0.020). Moreover, HCWs who suffered from pulmonary disease (OR = 3.7, CL 95%: 1.35–10.53; p-value = 0.007) or overweight (OR = 1.6 CL 95%: 1.05–2.56; p-value = 0.029) had an increased risk of developing 35-LC. Conclusions: Long COVID is an emerging problem for hospital managers as it may reduce the number of HCWs deployed in the fight against COVID-19. High BMI and previous pulmonary disease could be risk factors for 35-LC development in exposed HCWs.

In the pre-registration trial, data on the efficacy of the BNT162b2 mRNA vaccine against SARS-CoV-2 infection were not collected. The aim of this study was to evaluate vaccine effectiveness (VE) against documented infection. Bari Policlinico University-Hospital healthcare workers (HCWs) who completed the vaccination schedule were matched with HCWs who had refused vaccination. The VE for documented infection was 61.9% (95%CI=19.2–82.0%) 14–20 days after the first dose, 87.9% (95%CI=51.7–97.0%) 21–27 days after the first dose, and 96.0% (95%CI=82.2–99.1) 7 or more days after the second dose. Unvaccinated HCWs remain a concern even in the context of pandemic emergency.

Highlights This study included 3570 healthcare workers underwent naso and oropharyngeal swabs. The workers were divided into two groups based on COVID-19 patient contact type. SARS-CoV-2 infection prevalence is 0.45% (25 workers of 5750 subjected to protocol). We found 0.52% positive in the low-risk group, 13.16% in the high-risk group. Prevention procedures reduce the risk related to SARS-CoV-2 for healthcare workers.

Since the beginning in December 2019, the SARS-CoV-2 outbreak appeared to affect mostly the adult population, sparing the vast majority of children who only showed mild symptoms. The purpose of this investigation is to assess the status on the mechanisms that give children and infants this variation in epidemiology compared to the adult population and its impact on therapies and vaccines that are aimed towards them. A literature review, including in vitro studies, reviews, published guidelines and clinical trials was performed. Clinical trials concerned topics that allowed a descriptive synthesis to be produced. Four underlying mechanisms were found that may play a key role in providing COVID-19 protection in babies. No guidelines are available yet for therapy due to insufficient data; support therapy remains the most used. Only two vaccines are approved by the World Health Organization to be used in children from 12 years of age, and there are currently no efficacy or safety data for children below the age of 12 years. The COVID-19 clinical frame infection is milder in children and adolescents. This section of the population can act as vectors and reservoirs and play a key role in the transmission of the infection; therefore, vaccines are paramount. More evidence is required to guide safely the vaccination campaign.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-related infection has a major impact on public health, and healthcare workers (HCWs) are exposed to high biological risk. This paper describes the prevention procedures introduced at the University Hospital of Bari, Italy to reduce the risk to HCWs, consisting of enhanced preventive measures and activation of a report system to collect HCWs' contacts. Twenty-three confirmed cases of infection (0.4% of all HCWs) were reported in the 30-day observation period following implementation of the protocol. This shows that correct management of HCWs' contacts is essential to avoid nosocomial clusters.