Detection of Echovirus 11 lineage 1 in wastewater samples in Sicily.

We report the presence of Echovirus 11 (E11) in wastewater in Sicily (Southern Italy), since August 2022. Overall, the 5.4 % of sewage samples (7/130) collected in 2022 were positives for E11 and then the percentage of E11-positive sewage samples reached the value of 27.27(18/66) in the first semester of 2023. Phylogenetic analysis of VP1 sequences showed for most E11-positive samples (16/25: 64 %) close genetic correlation (98.4-99.4 % nucleotide identity) to E11 lineage 1 strains involved in recently reported severe neonatal infections.

Biological Specimen Banking as a Time Capsule to Explore the Temporal Dynamics of Norovirus Epidemiology.

Norovirus is recognised as a major cause of epidemic and sporadic acute gastroenteritis (AGE) in all age groups. Information on the genetic diversity of the noroviruses circulating in the 1980s and 1990s, before the development and adoption of dedicated molecular assays, is limited compared with the last decades. Between 1986 and 2020, uninterrupted viral surveillance was conducted in symptomatic children hospitalized with AGE in Palermo, Italy, providing a unique time capsule for exploring the epidemiological and evolutionary dynamics of enteric viruses. A total of 8433 stool samples were tested using real-time RT-PCR. All samples were stored at -20 or -80 °C until processing. In this 35-year long time span, noroviruses of genogroup II (GII) were detected in 15.6% of AGE requiring hospitalization, whilst GI noroviruses were detected in 1.4% of AGE. Overall, the predominant norovirus capsid (Cap) genotype was GII.4 (60.8%), followed by GII.3 (13.3%) and GII.2 (12.4%). Temporal replacement of the GII.4 Cap variants associated with different polymerase (Pol) types were observed over the study period. The chronology of emergence and circulation of the different GII.4 variants were consistent with data available in the literature. Also, for GII.3 and GII.2 NoVs, the circulation of different lineages/strains, differing in either the Cap or Pol genes or in both, was observed. This long-term study revealed the ability of noroviruses to continuously and rapidly modify their genomic makeup and highlights the importance of surveillance activities in vaccine design.

An Analysis of the Neutralizing Antibodies against the Main SARS-CoV-2 Variants in Healthcare Workers (HCWs) Vaccinated against or Infected by SARS-CoV-2.

Although the anti-COVID-19 vaccination has proved to be an effective preventive tool, "breakthrough infections" have been documented in patients with complete primary vaccination courses. Most of the SARS-CoV-2 neutralizing antibodies produced after SARS-CoV-2 infection target the spike protein receptor-binding domain which has an important role in facilitating viral entry and the infection of the host cells. SARS-CoV-2 has demonstrated the ability to evolve by accumulating mutations in the spike protein to escape the humoral response of a host. The aim of this study was to compare the titers of neutralizing antibodies (NtAbs) against the variants of SARS-CoV-2 by analyzing the sera of recovered and vaccinated healthcare workers (HCWs). A total of 293 HCWs were enrolled and divided into three cohorts as follows: 91 who had recovered from SARS-CoV-2 infection (nVP); 102 that were vaccinated and became positive after the primary cycle (VP); and 100 that were vaccinated with complete primary cycles and concluded the follow-up period without becoming positive (VN). Higher neutralization titers were observed in the vaccinated subjects' arms compared to the nVP subjects' arms. Differences in neutralization titers between arms for single variants were statistically highly significant (p < 0.001), except for the differences between titers against the Alpha variant in the nVP and in VP groups, which were also statistically significant (p < 0.05). Within the nVP group, the number of subjects with an absence of neutralizing antibodies was high. The presence of higher titers in patients with a complete primary cycle compared to patients who had recovered from infection suggested the better efficacy of artificial immunization compared to natural immunization, and this further encourages the promotion of vaccination even in subjects with previous infections.

Neutralizing Antibodies Response against SARS-CoV-2 Variants of Concern Elicited by Prior Infection or mRNA BNT162b2 Vaccination.

In order to determine the humoral protective response against SARS-CoV-2, the vaccine-induced and naturally induced neutralizing antibodies (NtAbs) responses against SARS-CoV-2 variants circulating in Italy through in vitro live virus neutralization assay were evaluated. A total of 39 SARS-CoV-2 recovered subjects (COVID-19+) and 63 subjects with a two-dose cycle of the BNT16262 vaccine were enrolled. A single serum sample was tested for COVID-19+ at 35-52 days post-positive swab, while vaccinees blood samples were taken at one (V1) and at three months (V3) after administration of the second vaccine dose. Significantly higher NtAb titers were found against B.1 and Alpha in both COVID-19+ and vaccinees, while lower NtAb titers were detected against Delta, Gamma, and Omicron variants. A comparison between groups showed that NtAb titers were significantly higher in both V1 and V3 than in COVID-19+, except against the Omicron variant where no significant difference was found. COVID-19+ showed lower neutralizing titers against all viral variants when compared to the vaccinees. Two-dose vaccination induced a sustained antibody response against each analyzed variant, except for Omicron. The evolution process of SARS-CoV-2, through variants originating from an accumulation of mutations, can erode the neutralizing effectiveness of natural and vaccine-elicited immunity. Therefore, a need for new vaccines should be evaluated to contain the ongoing pandemic.

Effect of COVID-19 quarantine on cognitive, functional and neuropsychiatric symptoms in patients with mild cognitive impairment and dementia.

BACKGROUND: During the last two years, COVID-19 affected older people with dementia or mild cognitive impairment (MCI), but conflicting and sparse results are still present. The objective of this study was to investigate the frequency and type of changes in functional, cognitive and behavioral and psychological symptoms of dementia (BPSD), and caregiver's stress during the period of quarantine in 2020 in patients affected by dementia/MCI living in Palermo, Sicily. METHODS: Outpatients affected by MCI/dementia were evaluated before and after COVID-19 quarantine. Functional status was investigated using basic and instrumental activities of daily living (ADL); cognitive performance with the mini-mental state examination; BPSD through the neuropsychiatric inventory (NPI). All scales were reported as pre/post-COVID-19 quarantine and a logistic regression analysis was performed for investigating the factors associated with worsening in NPI in patients and their caregivers. RESULTS: One hundred patients (mean age 77.1; females = 59%) were evaluated over a median of 10 months. In the sample as whole, a significant decline in functional and cognitive status was observed (p < 0.001 for both comparisons). The NPI significantly increased by 3.56 ± 8.96 points after the COVID-19 quarantine (p < 0.0001), while the caregivers' stress increased by 1.39 ± 3.46 points between the two evaluations (p < 0.0001). The decline was more evident in people with milder dementia. Higher values of instrumental ADL at baseline were associated with a significant lower worsening in NPI and caregiver's stress. CONCLUSIONS: COVID-19 quarantine negatively affected functional, cognitive, and neuropsychiatric symptoms in older people affected by dementia/MCI, highlighting the impact of COVID-19 quarantine for this population.