Immune Responses to SARS-CoV-2 Infection and Vaccine in a Big Italian COVID-19 Hospital: An 18-Month Follow-Up.

OBJECTIVES: This is a longitudinal prospective study which was designed to assess the trend of anti-SARS-CoV-2 antibodies targeting the Spike (anti-S) and Nucleocapside protein (anti-N) viral antigens over a 9-month period after the administration of an anti-SARS-CoV-2 vaccine in a big COVID-19 hospital located in Northern Italy. PARTICIPANTS: 7411 vaccinated workers were included in a linear mixed-effect model analysis performed to model the anti-S decay over the 9 months following the vaccination, during serological screening performed approximately 2, 4, and 9 months following the first jab administration. Serological tests performed in the 9 months preceding vaccine administration were retrospectively analysed to identify the burden of infections occurring before vaccination. RESULTS: The serological assays were used for monitoring the antibody titres during the observational period. Vaccination significantly reduced the rate of infection and elicited a specific humoral response, which lasted during the whole observational period (9 months). A decay was observed in all considered subgroups. At 35 weeks, workers with no history of pre-vaccine infection showed a significantly lower anti-S titre (-2522 U/mL on average (-2589.7 to -2445.7)); younger workers showed significantly higher anti-S titres (140.2 U/mL on average (82.4 to 201.3)). Only seven immunocompromised workers did not show significant levels of anti-S antibodies; three of them, all females, showed a specific T-cell response. CONCLUSIONS: Comparing the 9-month periods before and after the first vaccine dose, a significant reduction in infection rate was observed (1708 cases vs. 156). Pre-vaccine infection, especially if contracted during the first pandemic wave, greatly enhanced the response to vaccination, which was significantly affected also by age both in extent and duration (inversely related). A gender effect on the T-cell immune response was observed in a small group of workers who did not produce antibodies after vaccine administration.

Neurologic and cognitive sequelae after SARS-CoV2 infection: Different impairment for ICU patients.

The exact incidence of neurological and cognitive sequelae of COVID-19 in the long term is yet unknown. The aim of this research is to investigate the type of neurological and cognitive impairment in COVID-19 cases of different severity. Two hundred fifteen patients, who had developed COVID-19, were examined 4 months after the diagnosis by means of neurological exam and extensive cognitive evaluation, investigating general cognition, memory, verbal fluency, visuospatial abilities and executive functions. Fifty-two of them were treated in intensive care unit (ICU patients), whereas 163 were not hospitalized (non-ICU patients). Neurological deficits were found in 2/163 (1.2%) of non-ICU and in 7/52 (13.5%) of the ICU cases, all involving the peripheral nervous system. ICU patients performed significantly worse in all the neuropsychological tests and showed a worse age- and education-corrected cognitive impairment: Cognitive Impairment Index (CII) was higher in ICU than in non-ICU patients (median ICU 3 vs 2, p = .001). CII significantly correlated with age in both groups, was unrelated to length of follow- up, diabetes and hypertension and - only for ICU patients- to PaO2/FiO2 at ICU admission. Obtained results support the greater susceptibility of COVID-19 patients, treated in ICU, to develop neurological deficits and cognitive impairment at a four-month follow up, as compared to cases with mild/moderate symptoms.

QuantiFERON-TB Gold test in the identification of latent tuberculosis infection in immigrants.

BACKGROUND: The identification and treatment of latent tuberculosis infection (LTBI) among immigrants are an effective strategy for TB control in developed countries. A new test for LTBI identification that uses more specific antigens of Mycobacterium tuberculosis is now commercially available under the brand name of QuantiFERON-TB Gold test. OBJECTIVE: To compare QuantiFERON-TB Gold test to tuberculin skin testing (TST) for the detection of LTBI among immigrants from high endemic TB areas. PATIENTS AND METHODS: Undocumented immigrants attending a district medical center were enrolled if they originated from high endemic TB areas, the time of arrival in Italy was < or = 5 years, had neither active TB disease nor known immunodeficiency status. The TST was applied according to standards and QuantiFERON-TB Gold test was performed following the manufacturer's instructions. RESULTS: Hundred subjects were included in the comparative analysis. TST was positive in 44% of subjects; 15% had a positive QuantiFERON-TB Gold test result. The total agreement between TST and QuantiFERON-TB Gold test was 71%, for a kappa statistics of 0.37; agreement was 100% for TST negative results, but only 34% for TST positive ones. In the multivariate logistic regression analysis, previous BCG vaccination was independently associated with a lower chance of disagreement between the tests. CONCLUSION: The prevalence of LTBI among immigrants was lower when determined by QuantiFERON-TB Gold; this may be a consequence of more specific MTB antigens used. Our results suggest that QuantiFERON-TB Gold may be used as confirmatory test for TST positive immigrants candidate to preventive therapy.