98 research outputs found
People with asymptomatic or unrecognised infection potentially contribute to monkeypox virus transmission
No abstract availabl
Parainfluenza viruses: A trigger for type 1 diabetes new onset?
Type 1 diabetes (T1DM) ethiopathogenesis is still being studied, since the role of environmental factors , especially viruses, is not yet clear. This study was conducted on 31 paediatric patients with T1DM at onset. We analysed: Coxsackieviruses A (CoxA), Coxsackieviruses B (CoxB), Echoviruses (Echo); Influenzavirus A and B (IV-A and IV-B); Adenovirus (AdV); Parainfluenza viruses 1-2 and 3 (PiV 1-2-3); Cytomegalovirus (CMV) and Respiratory Syncytial Virus (RSV). Enteroviruses, especially CoxB and Echo, are most represented. Unexpectedly, Parainfluenza viruses were detected in seasonal subgroups, with peaks in autumn and spring, and spread homogeneously in different age groups
Evaluation of a ddPCR Commercial Assay for the Absolute Quantification of the Monkeypox Virus West Africa in Clinical Samples
Background: Monkeypox virus (MPXV) is a double-stranded DNA virus belonging to the orthopoxvirus genus in the family Poxviridae. Distinct clades are identified: the clade I belonging to the Central African (or Congo Basin) clade and the subclades IIa and IIb belonging to the West African clade. Here, a commercial droplet digital PCR (ddPCR) assay was evaluated for the quantification of the MPXV West Africa clade in clinical samples. Methods: The ddPCR reaction was assessed as a duplex assay using RPP30 as an internal amplification control. A total of 60 clinical specimens were tested, 40 positives (skin lesions, n=10; rectal swabs, n = 10; pharyngeal swabs, n = 10; and whole blood, n = 10), and 20 negatives (n = 5 for each biological matrix) were found at the routine molecular diagnostics (orthopoxvirus qPCR followed by confirmation with Sanger sequencing). To evaluate the analytical sensitivity, the ddPCR reaction was first analyzed on serial dilutions of synthetic DNA spiked in water and in negative biological matrices, achieving a limit of detection of 3.5 copy/µL. Results: Regarding the clinical samples, compared to routine molecular diagnostics, the ddPCR duplex assay showed 100% of specificity for all biological matrices and 100% sensitivity (10/10) for lesions, 100% (10/10) for rectal swabs, 90% (9/10) for pharyngeal swabs, and 60% (6/10) for whole blood. Conclusion: Overall, our data showed that the commercial ddPCR assay allowed the DNA detection of MPXV in 87.5% (35/40) of our cohort, highlighting useful technical indications for the different specimens with a potential greatest performance for skin lesions and rectal swabs
Monkeypox 2022 outbreak in non-endemic countries: Open questions relevant for public health, nonpharmacological intervention and literature review
Starting from mid-May 2022, cases of human monkeypox started to rise in several non-endemic countries. By mid-July, more than 17000 confirmed/suspect cases have been reported by at least 82 countries worldwide, with a regular incremental trend. In order to contain the disease diffusion, risk evaluation is crucial to undertake informed decisions and effective communication campaigns. However, since orthopoxvirus infections so far have attracted low attention, due to the eradication of smallpox 40 years ago, and to the confinement of human monkeypox almost exclusively to endemic areas, several unresolved issues concerning natural history, ecology and pathogenesis remain. To this respect, we identified some open questions and reviewed the relevant literature on monkeypoxvirus and/or related orthopoxviruses. The results will be discussed in the perspective of their relevance to public health decisions, particularly those related to non-pharmacological interventions
Strong immunogenicity of heterologous prime-boost immunizations with the experimental vaccine GRAd-COV2 and BNT162b2 or ChAdOx1-nCOV19
Here we report on the humoral and cellular immune response in eight volunteers who autonomously chose to adhere to the Italian national COVID-19 vaccination campaign more than 3 months after receiving a single-administration GRAd-COV2 vaccine candidate in the context of the phase-1 clinical trial. We observed a clear boost of both binding/neutralizing antibodies as well as T-cell responses upon receipt of the heterologous BNT162b2 or ChAdOx1-nCOV19 vaccines. These results, despite the limitation of the small sample size, support the concept that a single dose of an adenoviral vaccine may represent an ideal tool to effectively prime a balanced immune response, which can be boosted to high levels by a single dose of a different vaccine platform
Comparative analysis of bioinformatics tools to characterize SARS-CoV-2 subgenomic RNAs
During the replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), positive-sense genomic RNA and subgenomic RNAs (sgRNAs) are synthesized by a discontinuous process of transcription characterized by a template switch, regulated by transcription-regulating sequences (TRS). Although poorly known about makeup and dynamics of sgRNAs population and function of its constituents, next-generation sequencing approaches with the help of bioinformatics tools have made a significant contribution to expand the knowledge of sgRNAs in SARS-CoV-2. For this scope to date, Periscope, LeTRS, sgDI-tector, and CORONATATOR have been developed. However, limited number of studies are available to compare the performance of such tools. To this purpose, we compared Periscope, LeTRS, and sgDI-tector in the identification of canonical (c-) and non-canonical (nc-) sgRNA species in the data obtained with the Illu-mina ARTIC sequencing protocol applied to SARS-CoV-2–infected Caco-2 cells, sampled at different time points. The three software showed a high concordance rate in the identification and in the quantification of c-sgRNA, whereas more differences were observed in nc-sgRNA. Overall, LeTRS and sgDI-tector result to be adequate alternatives to Periscope to analyze Fastq data from sequencing platforms other than Nanopore
Early Diagnosis and Monitoring of Adaptive Immune Response in a Cohort of Mild Mpox Patients During the 2022 Wave
Unlabelled: Our study wanted to describe the kinetics of serological and adaptive immune responses in mpox patients. Methods: Fourteen patients with laboratory-confirmed mpox were tested at different time points after the symptom onset. An immunofluorescence assay was performed to evaluate the seroconversion kinetics of specific IgA, IgM, and IgG. Moreover, the characterization of the adaptive immunological profile of T- and B-cells was performed. Results: The antibody kinetics revealed the faster and more effective seroconversion of specific IgA than IgM. Moreover, we detected an increase in Active memory B cells and CD8+ cells in the early phases of infection, and a reduction in CD4+ T-cells in the mpox patients with respect to the controls and found the presence of higher levels of Treg cells in the HIV+ patients in the early phase of infection. Conclusion: Our data highlight the relevance of specific IgA testing early after the symptom onset, suggesting a possible role as a marker in early diagnosis, especially in close contact subjects. Furthermore, the different maturation states of effector cells in HIV+ patients, together with high Treg levels, may lead us to better understand the role of MPXV-HIV co-infection and identify potential cellular markers to monitor the excessive immune activation involved in mpox disease progression
Subjects who developed SARS-CoV-2 specific IgM after vaccination show a longer humoral immunity and a lower frequency of infection
Background: We have previously shown that eliciting SARS-CoV-2-specific IgM after vaccination is associated with higher levels of SARS-CoV-2 neutralizing IgG. This study aims to assess whether IgM development is also associated with longer-lasting immunity. Methods: We analysed anti-SARS-CoV-2 spike protein IgG and IgM (IgG-S, IgM-S), and anti-nucleocapsid IgG (IgG-N) in 1872 vaccinees at different time points: before the first dose (D1; w0), before the second dose (D2; w3) at three (w6) and 23 weeks (w29) after D2; moreover, 109 subjects were further tested at the booster dose (D3, w44), at 3 weeks (w47) and 6 months (w70) after D3. Two-level linear regression models were used to evaluate the differences in IgG-S levels. Findings: In subjects who had no evidence of a previous infection at D1 (non-infected, NI), IgM-S development after D1 and D2 was associated with higher IgG-S levels at short (w6, p < 0.0001) and long (w29, p < 0.001) follow-up. Similar IgG-S levels were observed after D3. The majority (28/33, 85%) of the NI subjects who had developed IgM-S in response to vaccination did not experience infection. Interpretation: The development of anti-SARS-CoV-2 IgM-S following D1 and D2 is associated with higher IgG-S levels. Most individuals who developed IgM-S never became infected, suggesting that IgM elicitation may be associated with a lower risk of infection. Funding: "Fondi Ricerca Corrente" and "Progetto Ricerca Finalizzata" COVID-2020 (Italian Ministry of Health); FUR 2020 Department of Excellence 2018-2022 (MIUR, Italy); the Brain Research Foundation Verona
Transmission of autochthonous Aedes-borne arboviruses and related public health challenges in Europe 2007–2023: a systematic review and secondary analysis
Background
Local transmission of dengue, chikungunya, and Zika infection is an emerging public health threat in Europe. Monitoring the epidemiological trends can help define the intervention strategy. The aim of this work was to analyse epidemiological characteristics of autochthonous transmission of Aedes-borne arboviruses in Europe.
Methods
A systematic review of the literature published from January 1, 2007, to January 31, 2024, reporting autochthonous cases of dengue, chikungunya, and Zika detected in Europe was performed. We searched MEDLINE, EMBASE, and the ECDC reports. Descriptive statistics and a secondary analysis were used to summarize the epidemiological characteristics of local transmission events (LTEs), explore potential temporal trends and identify relevant associations between epidemiological variables. Time intervals between key events were analysed to identify potential delays in LTE identification and intervention.
Findings
A total of 59 studies were included, describing 56 LTEs. The frequency of LTEs increased over time, with an average of 1.25 (95% CI: 1.17–1.35) times increment every year. While the highest number of dengue LTEs was reported in France (N = 37), Italy faced the largest number of cases detected in an LTE (N = 41). Considering all the arboviral LTEs, the median time between the symptom onset of the primary case and the diagnosis of the index case (“outbreak detection”) was 35.5 days (range 23.0–76.0). Only for chikungunya, higher delays correlated with higher cumulative number of cases detected per LTE, though this may be biased due to the low sample size.
Interpretation
We have observed a gradual increase of Aedes-borne arboviral LTEs in Europe over time, and a considerable delay in outbreak detection. Improving the timeliness of LTE identification is essential
Risk and predictive factors of prolonged viral RNA shedding in upper respiratory specimens in a large cohort of COVID-19 patients admitted to an Italian reference hospital
Background: Limited data are available about the predictors and outcomes associated with prolonged SARS-CoV-2 RNA shedding (VS).
Methods: A retrospective study including COVID-19 patients admitted to an Italian hospital between March 1 and July 1, 2020. Predictors of viral clearance (VC) and prolonged VS from the upper respiratory tract were assessed by Poisson regression and logistic regression analyses. The causal relation between VS and clinical outcomes was evaluated through an inverse probability weighted Cox model.
Results: The study included 536 subjects. The median duration of VS from symptoms onset was 18 days. The estimated 30-day probability of VC was 70.2%. Patients with comorbidities, lymphopenia at hospital admission, or moderate/severe respiratory disease had a lower chance of VC. The development of moderate/severe respiratory failure, delayed hospital admission after symptoms onset, baseline comorbidities, or D-dimer >1000ng/mL at admission independently predicted prolonged VS. The achievement of VC doubled the chance of clinical recovery and reduced the probability of death/mechanical ventilation.
Conclusions: Respiratory disease severity, comorbidities, delayed hospital admission and inflammatory markers negatively predicted VC, which resulted to be associated with better clinical outcomes. These findings highlight the importance of prompt hospitalization of symptomatic patients, especially where signs of severity or comorbidities are present
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