Nitrogen dioxide pollution increases vulnerability to COVID-19 through altered immune function.

Previous ecological studies suggest the existence of possible interplays between the exposure to air pollutants and SARS-CoV-2 infection. Confirmations at individual level, however, are lacking. To explore the relationships between previous exposure to particulate matter < 10 µm (PM10) and nitrogen dioxide (NO2), the clinical outcome following hospital admittance, and lymphocyte subsets in COVID-19 patients with pneumonia. In 147 geocoded patients, we assessed the individual exposure to PM10 and NO2 in the 2 weeks before hospital admittance. We divided subjects according to the clinical outcome (i.e., discharge at home vs in-hospital death), and explored the lymphocyte-related immune function as an index possibly affecting individual vulnerability to the infection. As compared with discharged subjects, patients who underwent in-hospital death presented neutrophilia, lymphopenia, lower number of T CD45, CD3, CD4, CD16/56 + CD3 + , and B CD19 + cells, and higher previous exposure to NO2, but not PM10. Age and previous NO2 exposure were independent predictors for mortality. NO2 concentrations were also negatively related with the number of CD45, CD3, and CD4 cells. Previous NO2 exposure is a co-factor independently affecting the mortality risk in infected individuals, through negative immune effects. Lymphopenia and altered lymphocyte subsets might precede viral infection due to nonmodifiable (i.e., age) and external (i.e., air pollution) factors. Thus, decreasing the burden of air pollutants should be a valuable primary prevention measure to reduce individual susceptibility to SARS-CoV-2 infection and mortality.

Bamlanivimab and Etesevimab administered in an outpatient setting for SARS-CoV-2 infection.

The early administration of anti-SARS-CoV-2 monoclonal antibodies (mAb) could decrease the risk of severe disease and the need of inpatients care. Herein, our clinical experience with Bamlanivimab/Etesevimab for the treatment of early SARS-CoV-2 infection through an outpatient service was described. Patients with confirmed COVID-19 were selected by General Practitioners (GPs) if eligible to mAb administration, according to manufacturer and AIFA (Agenzia-Italiana-del-Farmaco) criteria. If suitability was confirmed by the Multidisciplinary Team, the patient was evaluated within the next 48-72 hours. Then, all patients underwent a medical evaluation, followed by mAb infusion or hospitalization if the medical condition had worsened. Overall, from March 29th to June 4th, 2021, 106 patients with confirmed COVID-19 were identified by GPs; 26 were considered not eligible and then excluded, while 9 refused treatment. Among the 71 remaining, 6 were not treated because of worsening of symptoms soon after selection. Finally, 65 received mAb therapy. All treated patients survived. However, 2/65 developed adverse events (allergic reaction and atrial fibrillation, respectively) and 6/65 needed hospitalization. By performing univariate logistic regression analysis, diabetes was the only risk factor for hospitalization after mAb administration [aOR = 9.34, 95%CI = 1.31-66.49, p= .026]. Importantly, subjects who worsened awaiting mAb were more frequently obese (OR = 16.66, 95%CI = 1.80-153.9, p= .013) and received home corticosteroid therapy for COVID-19 (OR = 14.11, 95%CI = 1.53-129.6, p= .019). Establishing a network among GPs and COVID units could be an effective strategy to provide mAb treatment to patients with early SARS-CoV-2 infection to reduce hospitalizations and pressure on healthcare systems.