Risultati per: L’eparina inibisce la proteina spike del virus SARS-Cov-2

We read with interest the recent report by Liu et al1 describing faecal microbiome differences with postacute sequelae of SARS-CoV-2 (PASC), commonly referred to as ‘Long-COVID’. We have previously reported elevated levels of SARS-CoV-2-specific T cells with PASC compared with resolved COVID-19 (RC; no lingering symptoms at the time of sample collection) that correlated with increased levels of the inflammatory marker IL-6, suggesting that elevated inflammation in PASC may be related to immune response to residual virus.2 Although several studies have reported gut microbiome differences during acute COVID-19,3 PASC has received less attention. We, thus, sought to characterise gut microbiome differences in PASC versus RC using faecal samples from our study2 and to relate these differences to inflammation. The faecal microbiome was evaluated using 16S rRNA gene sequencing. Plasma levels of inflammatory markers IL-6 and C reactive protein (CRP) were measured…

Objectives
Healthcare workers (HCWs) are on the frontline of combating COVID-19, hence are at elevated risk of contracting an infection with SARS-CoV-2. The present study aims to measure the impact of SARS-CoV-2 on HCWs in central sub-Saharan Africa.

Setting
A cross-sectional serological study was conducted at six urban and five rural hospitals during the first pandemic wave in the South Kivu province, Democratic Republic of the Congo (DRC).

Participants
Serum specimens from 1029 HCWs employed during the first pandemic wave were collected between August and October 2020, and data on demographics and work-related factors were recorded during structured interviews.

Primary and secondary outcome measures
The presence of IgG antibodies against SARS-CoV-2 was examined by ELISA. Positive specimens were further tested using a micro-neutralisation assay. Factors driving SARS-CoV-2 seropositivity were assessed by multivariable analysis.

Results
Overall SARS-CoV-2 seroprevalence was high among HCWs (33.1%), and significantly higher in urban (41.5%) compared with rural (19.8%) hospitals. Having had presented with COVID-19-like symptoms before was a strong predictor of seropositivity (31.5%). Personal protective equipment (PPE, 88.1% and 11.9%) and alcohol-based hand sanitizer (71.1% and 28.9%) were more often available, and hand hygiene was more often reported after patient contact (63.0% and 37.0%) in urban compared with rural hospitals, respectively. This may suggest that higher exposure during non-work times in high incidence urban areas counteracts higher work protection levels of HCWs.

Conclusions
High SARS-CoV-2 seropositivity indicates widespread transmission of the virus in this region of DRC. Given the absence of publicly reported cases during the same time period at the rural sites, serological studies are very relevant in revealing infection dynamics especially in regions with low diagnostic capacities. This, and discrepancies in the application of PPE between urban and rural sites, should be considered in future pandemic response programmes.

Maria Van Kerkhove, responsabile tecnico per Covid-19 all’Oms: «I casi e i ricoveri per Covid sono in aumento da mesi»

This cohort study compares the mortality and hospitalization risks among patients with vs without solid cancer and diagnosed with COVID-19 during the period when the Omicron variant was dominant.

Objective
This study was to explore the changes in bacterial bloodstream infection (BSI) in patients with haematological malignancies (HMs) before and during SARS-CoV-2 pandemic.

Design
Retrospective cohort study between 2018 and 2021.

Setting
The largest haematological centre in southern China.

Results
A total of 599 episodes of BSI occurring in 22 717 inpatients from January 2018 to December 2021 were analysed. The frequencies of the total, Gram-negative and Gram-positive BSI before and during the pandemic were 2.90% versus 2.35% (p=0.011), 2.49% versus 1.77% (p

Objectives
The rapid spread of the SARS-CoV-2 Omicron variant has raised concerns regarding waning vaccine-induced immunity and durability. We evaluated protection of the third-dose and fourth-dose mRNA vaccines against SARS-CoV-2 Omicron subvariant and its sublineages.

Design
Systematic review and meta-analysis.

Data sources
Electronic databases and other resources (PubMed, Embase, CENTRAL, MEDLINE, CINAHL PLUS, APA PsycINFO, Web of Science, Scopus, ScienceDirect, MedRxiv and bioRxiv) were searched until December 2022.

Study eligibility criteria
We included studies that assessed the effectiveness of mRNA vaccine booster doses against SARS-CoV-2 infection and severe COVID-19 outcomes caused by the subvariant.

Data extraction and synthesis
Estimates of vaccine effectiveness (VE) at different time points after the third-dose and fourth-dose vaccination were extracted. Random-effects meta-analysis was used to compare VE of the third dose versus the primary series, no vaccination and the fourth dose at different time points. The certainty of the evidence was assessed by Grading of Recommendations, Assessments, Development and Evaluation approach.

Results
This review included 50 studies. The third-dose VE, compared with the primary series, against SARS-CoV-2 infection was 48.86% (95% CI 44.90% to 52.82%, low certainty) at ≥14 days, and gradually decreased to 38.01% (95% CI 13.90% to 62.13%, very low certainty) at ≥90 days after the third-dose vaccination. The fourth-dose VE peaked at 14–30 days (56.70% (95% CI 50.36% to 63.04%), moderate certainty), then quickly declined at 61–90 days (22% (95% CI 6.40% to 37.60%), low certainty). Compared with no vaccination, the third-dose VE was 75.84% (95% CI 40.56% to 111.12%, low certainty) against BA.1 infection, and 70.41% (95% CI 49.94% to 90.88%, low certainty) against BA.2 infection at ≥7 days after the third-dose vaccination. The third-dose VE against hospitalisation remained stable over time and maintained 79.30% (95% CI 58.65% to 99.94%, moderate certainty) at 91–120 days. The fourth-dose VE up to 60 days was 67.54% (95% CI 59.76% to 75.33%, moderate certainty) for hospitalisation and 77.88% (95% CI 72.55% to 83.21%, moderate certainty) for death.

Conclusion
The boosters provided substantial protection against severe COVID-19 outcomes for at least 6 months, although the duration of protection remains uncertain, suggesting the need for a booster dose within 6 months of the third-dose or fourth-dose vaccination. However, the certainty of evidence in our VE estimates varied from very low to moderate, indicating significant heterogeneity among studies that should be considered when interpreting the findings for public health policies.

PROSPERO registration number
CRD42023376698.

Annals of Internal Medicine, Volume 176, Issue 12, December 2023.

Annals of Internal Medicine, Volume 176, Issue 12, December 2023.

New results suggest that a live-virus vaccine intended to protect against shingles—a condition caused by reactivation of the varicella-zoster virus, which also causes chickenpox—prevented illness in 67% of people in the first year after vaccination. But after 10 years, the vaccine’s efficacy against shingles, also known as herpes zoster, had declined to 15%. The study used electronic health record data from more than 500 000 adults aged 50 years or older who received the shot between 2007 and 2018 in California.

Rafforzare le vaccinazioni e la capacità ospedaliera

New England Journal of Medicine, Volume 389, Issue 24, Page 2299-2301, December 2023.

New England Journal of Medicine, Volume 389, Issue 24, Page 2276-2276, December 2023.

Oltre mille i casi in Europa, secondo anno record dopo il 2018

Annals of Internal Medicine, Ahead of Print.

Annals of Internal Medicine, Ahead of Print.

Objectives
The study aim was to evaluate vaccine effectiveness (VE) of COVID-19 vaccines in preventing symptomatic COVID-19 among healthcare workers (HCWs) in Zambia. We sought to answer the question, ‘What is the vaccine effectiveness of a complete schedule of the SARS-CoV-2 vaccine in preventing symptomatic COVID-19 among HCWs in Zambia?’

Design/setting
We conducted a test-negative case–control study among HCWs across different levels of health facilities in Zambia offering point of care testing for COVID-19 from May 2021 to March 2022.

Participants
1767 participants entered the study and completed it. Cases were HCWs with laboratory-confirmed SARS-CoV-2 and controls were HCWs who tested SARS-CoV-2 negative. Consented HCWs with documented history of vaccination for COVID-19 (vaccinated HCWs only) were included in the study. HCWs with unknown test results and unknown vaccination status, were excluded.

Primary and secondary outcome measures
The primary outcome was VE among symptomatic HCWs. Secondary outcomes were VE by: SARS-CoV-2 variant strains based on the predominant variant circulating in Zambia (Delta during May 2021 to November 2021 and Omicron during December 2021 to March 2022), duration since vaccination and vaccine product.

Results
We recruited 1145 symptomatic HCWs. The median age was 30 years (IQR: 26–38) and 789 (68.9%) were women. Two hundred and eighty-two (24.6%) were fully vaccinated. The median time to full vaccination was 102 days (IQR: 56–144). VE against symptomatic SARS-CoV-2 infection was 72.7% (95% CI: 61.9% to 80.7%) for fully vaccinated participants. VE was 79.4% (95% CI: 58.2% to 90.7%) during the Delta period and 37.5% (95% CI: –7.0% to 63.3%) during the Omicron period.

Conclusions
COVID-19 vaccines were effective in reducing symptomatic SARS-CoV-2 among Zambian HCWs when the Delta variant was circulating but not when Omicron was circulating. This could be related to immune evasive characteristics and/or waning immunity. These findings support accelerating COVID-19 booster dosing with bivalent vaccines as part of the vaccination programme to reduce COVID-19 in Zambia.