Daniel Pan et al.
Are clinical outcomes from COVID-19 improving in ethnic minority groups?
The Lancet, July 2023; doi.org/10.1016/j.eclinm.2023.102091
Abstract
Disproportionately worse COVID-19 clinical outcomes in people from ethnic minority groups have been a concern since early in the pandemic.1 Now as time progresses, it may be useful to look back at the evolving evidence base. We performed the first systematic review on clinical outcomes in ethnic minority groups in May 2020, where we found across several countries a higher proportion of patients from ethnic minority groups infected with SARS-CoV-2, admitted to intensive care units with COVID-19 and dying in hospitals due to COVID-19. However, the collected data was of too poor quality to allow meaningful data synthesis.2 Our findings were used as evidence for debate in UK Parliament in June 2020, resulting in a recommendation to mandate comprehensive ethnicity data collection and recording as part of routine hospital data collection systems.3
After some time, more studies started to emerge. This allowed us to conduct a meta-analysis to disentangle why ethnic minority groups were suffering disproportionately from the pandemic. In our second review, published in November 2020, we found that ethnic minority groups in the UK and USA had an increased risk of SARS-CoV-2 infection compared to those of White ethnicity. However, differences in hospitalization and death rates in this meta-analysis, when synthesised, was less clear.4 Whilst many studies reported a higher mortality rate from COVID-19 among ethnic minority groups compared to the majority groups, in the generation of mortality estimates, most did not take into account the number of infected individuals from ethnic minority groups in the community (see Fig. 1, Panel A). In our latest meta-analysis published in March 2023, now including over 200 million study participants globally, the risk of infection remained elevated across nearly all ethnic minority groups studied, compared to the majority group in each country.5 However, we observed far smaller differences for hospitalisation, intensive care admission and death following infection, although there was evidence of ethnic inequalities in these outcomes. Therefore, at least initially, it appeared that increased risk of infection was the main driver of the disproportionate outcomes in ethnic minority groups (see Fig. 1, Panel B). Our work was cited by the World Health Organization's living guideline on COVID-19 infection prevention and control, emphasizing the need for healthcare workers from ethnic minority groups to have equal access to personal protective equipment.
Concrete data identifying and quantifying factors relating to SARS-CoV-2 infection remains limited, compared to risk factors for developing severe disease once infected. In an immunologically naïve population, mathematical models have proposed that the increased risk of infection with an airborne pathogen is related to a higher frequency and/or duration of exposure to individuals who emit high quantities of the virus in poorly ventilated spaces.7 Infection is therefore most likely to occur in homes and workplaces with poor ventilation and in occupations involving public-facing roles such as healthcare, even during mandated national lockdowns, all of which are common among those from ethnic minority groups. The higher prevalence of multi-generational occupancy within the homes of ethnic minority groups, which are more likely to have poorer ventilation, may also predispose them to a higher risk of infection.
To complicate matters, we now know that past infection with SARS-CoV-2 provides immune protection against severe disease for at least 40 weeks following infection, regardless of variants.8 While COVID-19 in immunologically naïve populations may have resulted in worse clinical outcomes for ethnic minority groups compared to the majority groups, a history of previous infection in those who have survived their first infection, and therefore have existing immunity that protects against severe disease may have reduced the proportion of those who are susceptible to hospitalisation, intensive care admission and death from COVID-19 (see Fig. 1, Panel C). This could explain the UK's Office for National Statistics most recent report, which shows that the proportion of deaths from COVID-19 in ethnic minority groups are now comparable, and in some cases lower than that of the White British majority.9
Going forwards, we must implement tangible interventions that reduce the likelihood of infection among ethnic minority groups, which may still be ongoing. This will require policy-makers to address the longstanding inequalities that have led to an elevated risk of virus exposure in ethnic minority groups. In 2010, the Marmot review highlighted the need to reduce systemic racial inequalities in the UK and set clear policy objectives to address this. Ten years later, in the peak of the pandemic, the 2020 Marmot Review on Health Inequalities reported that housing affordability, declines in education funding, and an increase in zero-hour contracts are worse for ethnic minority groups compared to the previous report.10 Over the past three years, one thing has become clear: systemic inequality is likely the root cause of disproportionate deaths from the COVID-19 pandemic in ethnic minority groups. We now have a unique opportunity to rebuild, plan ahead and work with communities from ethnic minority groups. Only by reducing the systemic gap in the risk of infection can we reduce preventable deaths from the next global pandemic.
Amesh Adalja et al.
How Infectious Disease Experts Impacted the Coronavirus Disease 2019 Response: Lessons From the Front Lines
CID, June 2023 ; doi.org/10.1093/cid/ciad137
Abstract
In this article, we summarize findings from research conducted by the Johns Hopkins Center for Health Security and the Infectious Diseases Society of America to understand infectious disease (ID) workforce contributions to the coronavirus disease 2019 (COVID-19) response and their impacts. ID experts were found to have made diverse and unique contributions that went well beyond their usual responsibilities, with many spending several hours a week on these activities without additional compensation. These efforts were thought to not only build community resilience but also augment the ongoing public health response. Respondents also reported several hospital and clinical leadership roles taken on during the pandemic, such as developing protocols and leading clinical trials. We also make several policy recommendations, such as medical student debt relief and improved compensation, that will be needed to help fortify the ID workforce for future pandemics.
NofarAtari et al
Disinfection of SARS-CoV-2 by UV-LED 267 nm: comparing different variants
Nature, May 2023; doi.org/10.1038/s41598-023-35247-9
Abstract
UV irradiation is an efficient tool for the disinfection of viruses in general and coronavirus specifically. This study explores the disinfection kinetics of SARS-CoV-2 variants wild type (similar to the Wuhan strain) and three variants (Alpha, Delta, and Omicron) by 267 nm UV-LED. All variants showed more than 5 logs average reduction in copy number at 5 mJ/cm2 but inconsistency was evident, especially for the Alpha variant. Increasing the dose to 7 mJ/cm2 did not increase average inactivation but did result in a dramatic decrease in the inactivation inconsistency making this dose the recommended minimum. Sequence analysis suggests that the difference between the variants is likely due to small differences in the frequency of specific UV extra-sensitive nucleotide sequence motifs although this hypothesis requires further experimental testing. In summary, the use of UV-LED with their simple electricity need (can be operated from a battery or photovoltaic panel) and geometrical flexibility could offer many advantages in the prevention of SARS-CoV-2 spread, but minimal UV dose should be carefully considered.
David Benkeser et al.
Comparing antibody assays as correlates of protection against COVID-19 in the COVE mRNA-1273 vaccine efficacy trial
Science, April 2023; doi/10.1126/scitranslmed.ade9078
Abstract
The best assay or marker to define mRNA-1273 vaccine–induced antibodies as a correlate of protection (CoP) is unclear. In the COVE trial, participants received two doses of the mRNA-1273 COVID-19 vaccine or placebo. We previously assessed IgG binding antibodies to the spike protein (spike IgG) or receptor binding domain (RBD IgG) and pseudovirus neutralizing antibody 50 or 80% inhibitory dilution titer measured on day 29 or day 57, as correlates of risk (CoRs) and CoPs against symptomatic COVID-19 over 4 months after dose. Here, we assessed a new marker, live virus 50% microneutralizationtiter (LV-MN50), and compared and combined markers in multivariable analyses. LV-MN50 was an inverse CoR, with a hazard ratio of 0.39 (95% confidence interval, 0.19 to 0.83) at day 29 and 0.51 (95% confidence interval, 0.25 to 1.04) at day 57 per 10-fold increase. In multivariable analyses, pseudovirus neutralization titers and anti-spike binding antibodies performed best as CoRs; combining antibody markers did not improve correlates. Pseudovirus neutralization titer was the strongest independent correlate in a multivariable model. Overall, these results supported pseudovirus neutralizing and binding antibody assays as CoRs and CoPs, with the live virus assay as a weaker correlate in this sample set. Day 29 markers performed as well as day 57 markers as CoPs, which could accelerate immunogenicity and immunobridging studies.
Yupeng Feng et al.
Broadly neutralizing antibodies against sarbecoviruses generated by immunization of macaques with an AS03-adjuvanted COVID-19 vaccine
Science, May 2023; doi/10.1126/scitranslmed.adg7404
Abstract
The rapid emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants that evade immunity elicited by vaccination has placed an imperative on the development of countermeasures that provide broad protection against SARS-CoV-2 and related sarbecoviruses. Here, we identified extremely potent monoclonal antibodies (mAbs) that neutralized multiple sarbecoviruses from macaques vaccinated with AS03-adjuvanted monovalent subunit vaccines. Longitudinal analysis revealed progressive accumulation of somatic mutation in the immunoglobulin genes of antigen-specific memory B cells (MBCs) for at least 1 year after primary vaccination. Antibodies generated from these antigen-specific MBCs at 5 to 12 months after vaccination displayed greater potency and breadth relative to those identified at 1.4 months. Fifteen of the 338 (about 4.4%) antibodies isolated at 1.4 to 6 months after the primary vaccination showed potency against SARS-CoV-2 BA.1, despite the absence of serum BA.1 neutralization. 25F9 and 20A7 neutralized authentic clade 1 sarbecoviruses (SARS-CoV, WIV-1, SHC014, SARS-CoV-2 D614G, BA.1, and Pangolin-GD) and vesicular stomatitis virus–pseudotyped clade 3 sarbecoviruses (BtKY72 and PRD-0038). 20A7 and 27A12 showed potent neutralization against all SARS-CoV-2 variants and multiple Omicron sublineages, including BA.1, BA.2, BA.3, BA.4/5, BQ.1, BQ.1.1, and XBB. Crystallography studies revealed the molecular basis of broad and potent neutralization through targeting conserved sites within the RBD. Prophylactic protection of 25F9, 20A7, and 27A12 was confirmed in mice, and administration of 25F9 particularly provided complete protection against SARS-CoV-2, BA.1, SARS-CoV, and SHC014 challenge. These data underscore the extremely potent and broad activity of these mAbs against sarbecoviruses.
Fengwen Zhang et al
Pan-sarbecovirus prophylaxis with human anti-ACE2 monoclonal antibodies
Nature, May 2023; doi.org/10.1038/s41564-023-01389-9
Abstract
Human monoclonal antibodies (mAbs) that target the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein have been isolated from convalescent individuals and developed into therapeutics for SARS-CoV-2 infection. However, therapeutic mAbs for SARS-CoV-2 have been rendered obsolete by the emergence of mAb-resistant virus variants. Here we report the generation of a set of six human mAbs that bind the human angiotensin-converting enzyme-2 (hACE2) receptor, rather than the SARS-CoV-2 spike protein. We show that these antibodies block infection by all hACE2 binding sarbecoviruses tested, including SARS-CoV-2 ancestral, Delta and Omicron variants at concentrations of ~7–100 ng ml−1. These antibodies target an hACE2 epitope that binds to the SARS-CoV-2 spike, but they do not inhibit hACE2 enzymatic activity nor do they induce cell-surface depletion of hACE2. They have favourable pharmacology, protect hACE2 knock-in mice against SARS-CoV-2 infection and should present a high genetic barrier to the acquisition of resistance. These antibodies should be useful prophylactic and treatment agents against any current or future SARS-CoV-2 variants and might be useful to treat infection with any hACE2-binding sarbecoviruses that emerge in the future.
Elise Wouters et al.
Intranasal administration of convalescent plasma protects against SARS-CoV-2 infection in hamsters
ebioMedicine, May 2023; doi.org/10.1016/j.ebiom.2023.104597
Abstract
Convalescent plasma (CP) transfusion is an early option for treating infections with pandemic potential, often preceding vaccine or antiviral drug rollout. Heterogenous findings from randomized clinical trials on transfusion of COVID-19 CP (CCP) have been reported. However, meta-analysis suggests that transfusion of high titer CCP is associated with a mortality benefit for COVID-19 outpatients or inpatients treated within 5 days after symptom onset, indicating the importance of early administration.
Methods
We tested if CCP is an effective prophylactic against SARS-CoV-2 infection by the intranasal administration of 25 μL CCP/nostril (i.e. 0.01–0.06 mg anti-RBD antibodies/kg) in hamsters exposed to infected littermates.
Findings
In this model, 40% of CCP treated hamsters were fully protected and 40% had significantly reduced viral loads, the remaining 20% was not protected. The effect seems dose-dependent because high-titer CCP from a vaccinated donor was more effective than low-titer CCP from a donation prior to vaccine rollout. Intranasal administration of human CCP resulted in a reactive (immune) response in hamster lungs, however this was not observed upon administration of hamster CCP.
Interpretation
We conclude that CCP is an effective prophylactic when used directly at the site of primary infection. This option should be considered in future prepandemic preparedness plans.
Leila Valizadeh et al.
Stress management protocol for nurses working in the COVID-19 wards
Cell, April 2023; doi.org/10.1016/j.heliyon.2023.e15770
Abstract
Purpose
Due to necessity of immediate support strategies for nurses during COVID-19 pandemic and lack of comprehensive and applied standard guidelines, the present study was conducted to develop stress management protocol for nurses working in COVID-19 wards with an approach based on the best scientific evidences.
Methods
This descriptive methodological and validation study was conducted with evidence-based approach based on Stetler model in two hospitals of Iran in 2020. In order to identify the resources of stress and the solutions provided to deal with it to design the protocol, a comprehensive literature review was performed. After extracting evidence, they were ranked based on the levels of evidence and designed as a protocol. Quality appraisal of guideline was done using AGREEII instrument by an expert panel. The applicability of the protocol was assessed by a group of nurses through focus group discussion.
Results
Out of 184 studies, 28 articles related to the topic were selected. According to the expert panel, in the AGREEII domains, Scope and Purpose (87.5%) and Applicability (70.5%) were the highest and the lowest scores respectively. The “Stress Management Protocol for Nurses Working in COVID-19 Wards” was designed in six sections, which was elaborated relative to each stress resources. Members of the focus group mostly considered the evidence-based recommendations feasible by making suggestions to some items.
Conclusion
This study emphasized the important role of proper planning by health care system officials according to the designed protocol to manage stress and increase the self-efficacy of nurses in critical situations.
Alexandra M Blossey et al
VPM1002 as Prophylaxis Against Severe Respiratory Tract Infections Including Coronavirus Disease 2019 in the Elderly: A Phase 3 Randomized, Double-Blind, Placebo-Controlled, Multicenter Clinical Study
CID, November 2022; doi.org/10.1093/cid/ciac881
Abstract
Background
BacilleCalmette-Guérin (BCG) vaccination can potentially reduce the rate of respiratory infections in vulnerable populations. This study evaluates the safety and efficacy of VPM1002 (a genetically modified BCG) as prophylaxis against severe respiratory tract infections including coronavirus disease 2019 (COVID-19) in an elderly population.
Methods
In this phase 3, randomized, double-blind, placebo-controlled, multicenter clinical trial, healthy elderly volunteers (N = 2064) were enrolled, randomized (1:1) to receive either VPM1002 or placebo, and followed up remotely for 240 days. The primary outcome was the mean number of days with severe respiratory infections at hospital and/or at home. Secondary endpoints included the incidence of self-reported fever, number of hospital and intensive care unit (ICU) admissions, and number of adverse events.
Results
A total of 31 participants in the VPM1002 group reported at least 1 day with severe respiratory disease and a mean number of days with severe respiratory disease of 9.39 ± 9.28 while in the placebo group; 38 participants reported a mean of 14.29 ± 16.25 days with severe respiratory disease. The incidence of self-reported fever was lower in the VPM1002 group (odds ratio, 0.46 [95% confidence interval, .28–.74]; P = .001), and consistent trends to fewer hospitalization and ICU admissions due to COVID-19 were observed after VPM1002 vaccination. Local reactions typical for BCG were observed in the VPM1002-vaccinated group, which were mostly of mild intensity.
Conclusions
Vaccination with VPM1002 is well tolerated and seems to have a prophylactic effect against severe respiratory disease in the elderly.
Myron J Levin et al.
AZD7442 (Tixagevimab/Cilgavimab) for Post-Exposure Prophylaxis of Symptomatic Coronavirus Disease 2019
CID, November 2022; doi.org/10.1093/cid/ciac899
Abstract
Background
This phase 3 trial assessed AZD7442 (tixagevimab/cilgavimab) for post-exposure prophylaxis against symptomatic coronavirus disease 2019 (COVID-19).
Methods
Adults without prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or COVID-19 vaccination were enrolled within 8 days of exposure to a SARS-CoV-2–infected individual and randomized 2:1 to a single 300-mg AZD7442 dose (one 1.5-mL intramuscular injection each of tixagevimab and cilgavimab) or placebo. Primary end points were safety and first post-dose SARS-CoV-2 reverse-transcription polymerase chain reaction (RT-PCR)–positive symptomatic COVID-19 event before day 183.
Conclusions
This study did not meet the primary efficacy end point of post-exposure prevention of symptomatic COVID-19. However, analysis of participants who were SARS-CoV-2 RT-PCR–negative or missing an RT-PCR result at baseline support a role for AZD7442 in preventing symptomatic COVID-19.
Jennifer M Davis, Jonathan Z.
The Promise and Peril of Anti–Severe Acute Respiratory Syndrome Coronavirus 2 Monoclonal Antibodies
CID, November 2022; doi.org/10.1093/cid/ciac902
Abstract
Over the past 2 years, monoclonal antibodies (mAbs) directed against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein have been a linchpin in our therapeutic toolbox for coronavirus disease 2019 (COVID-19). In November 2020, the US Food and Drug Administration (FDA) provided emergency authorization for the first mAb combination for the treatment of outpatients. Since then, 6 antibody regimens have been authorized [1] for either treatment or prevention. However, the promise of the anti–SARS-CoV-2 mAb class of therapies has also been tempered by its sensitivity to the ever-changing variant landscape. In this editorial, we discuss the Phase III Double-blind, Placebo-controlled Study of AZD7442 (Tixagevimab/Cilgavimab) for Post-exposure Prophylaxis of Symptomatic COVID-19 (STORM CHASER) trial that is published in this issue of Clinical Infectious Diseases and also the emergence of variants that represent a threat to all of the currently FDA-authorized mAb regimens.
Tixagevimab/cilgavimab, also known as AZD7442 or Evusheld, is a combination neutralizing antibody against SARS-CoV-2 with an extended half-life. This regimen has been tested in phase 3 studies for 3 indications: pre-exposure prophylaxis (PROVENT trial), treatment of symptomatic COVID-19 (TACKLE trial), and post-exposure prophylaxis (STORM CHASER trial). In the PROVENT trial, a 300-mg intramuscular dose of tixagevimab/cilgavimab was found to be effective in preventing symptomatic COVID-19 infection in individuals who were at increased risk of poor response to vaccination and/or increased risk of exposure to SARS-CoV-2 [2]. Results from the TACKLE study also suggest that tixagevimab/cilgavimab may be efficacious in preventing progression to severe disease in unvaccinated individuals with SARS-CoV-2 infection [3]. However, at this time, tixagevimab/cilgavimabis currently approved only under emergency use authorization (EUA) by the FDA for pre-exposure prophylaxis for immunosuppressed individuals who are likely to have an impaired response to vaccination or for individuals in whom vaccination is contraindicated [4]. This regimen is not yet authorized for treatment of symptomatic COVID-19 or for post-exposure prophylaxis (in contrast, tixagevimab/cilgavimab is approved in other countries, including Canada, for COVID-19 treatment). In this issue of Clinical Infectious Diseases, Esser and colleagues report the results of the STORM CHASER trial for the use of tixagevimab/cilgavimab as post-exposure prophylaxis [5].
In the STORM CHASER trial, 1121 unvaccinated individuals aged ≥18 years who were exposed to SARS-CoV-2 within the previous 8 days and had no previous confirmed COVID-19 received either a 300-mg intramuscular injection of tixagevimab/cilgavimab (N = 749) or placebo (N = 372). The mean age of participants was 46 years, and 66% had at least 1 risk factor for severe COVID-19. A small proportion of participants were found to be SARS-CoV-2–seropositive at baseline: 34 (4.5%) in the intervention arm and 14 (3.8%) in the placebo arm. The primary efficacy analysis was performed shortly after the occurrence of the 25th primary end point, defined as the first incidence of post-dose SARS-CoV-2 reverse-transcription polymerase chain reaction (PCR)–positive symptomatic illness before study day 183. There was no significant difference between the 2 arms, as 3.1% of tixagevimab/cilgavimab-treated participants vs 4.6% of the placebo participants were found to have symptomatic COVID-19, representing a 33% relative risk reduction. An extended dataset with a longer duration of follow-up showed a marginally significant 43% reduction in symptomatic COVID-19.
Over the past 2 years, anti–SARS-CoV-2 mAbs targeting the spike protein have represented a key class of therapeutics for the prevention and treatment COVID-19. However, the spike protein is also under intense immunologic pressure [7] and also represents a key site of viral evolution for new variants of concern. One of the first signs that the activity of mAb regimens may be dependent on the circulating variants was the emergence of bamlanivimab/etesevimab resistance with the Beta (B.1.351) variant [8]. While the Delta (B.1.617.2) variant was susceptible to all mAbs, the fragility of the mAb class of antiviral therapies has again been highlighted with the arrival of Omicron (BA.1) and its subvariants. With each successive Omicron variant, there appears to be increasing resistance across the mAb class (Table 1). The BA.1 and BA.1.1 variants were resistant to both bamlanivimab/etesevimab and casirivimab/imdevimab regimens and necessitated an increased total dose of tixagevimab/cilgavimab to 600 mg based on modeling studies that showed the original 300 mg dose would have substantially reduced efficacy [9]. Next, the arrival of the BA.2 and BA.5 subvariants led to the loss of sotrovimab activity. In response, the FDA granted EUA for bebtelovimab with only phase 2 clinical trial results showing a reduction in SARS-CoV-2 RNA shedding and more rapid improvement in clinical symptoms [4]. However, we are now faced with emergent variants (eg, BQ.1.1, XBB) that are expected to be resistant to all mAbs, including bebtelovimab and tixagevimab/cilgavimab
While treatment options that appear to retain efficacy against Omicron and its subvariants remain, these regimens have drawbacks, including drug–drug interactions (for nirmatrelvir/ritonavir), complicated intravenous dosing (for remdesivir), and both lower expected efficacy and concerns surrounding mutagenesis (for molnupiravir). In addition, none of these regimens are authorized for pre-exposure prophylaxis. For these reasons, mAbs have continued to be widely used, especially tixagevimab/cilgavimab, for our immunocompromised patients who cannot effectively respond to vaccination. Now more than ever, we need nimble methods of designing and testing new mAbs that can keep pace with the changing landscape of variants. This may require the identification of mAb combinations that bind regions distinct from those commonly targeted by the immune system in response to vaccination or natural infection and would thus be under less evolutionary pressure for viral escape. Furthermore, we may need to dig deeper into our toolbox of antiviral strategies to further explore the use of therapies such as convalescent plasma [11], interferon lambda [12], and others that have shown promise in large-scale clinical trials. As we enter a new phase of the pandemic, we too will need to adapt if we are to continue keeping our patients safe from severe COVID-19.
Adrian Lison et al.
Effectiveness assessment of non-pharmaceutical interventions: lessons learned from the COVID-19 pandemic
The Lancet, April 2023; doi.org/10.1016/S2468-2667(23)00046-4
Abstract
Effectiveness of non-pharmaceutical interventions (NPIs), such as school closures and stay-at-home orders, during the COVID-19 pandemic has been assessed in many studies. Such assessments can inform public health policies and contribute to evidence-based choices of NPIs during subsequent waves or future epidemics. However, methodological issues and no standardised assessment practices have restricted the practical value of the existing evidence. Here, we present and discuss lessons learned from the COVID-19 pandemic and make recommendations for standardising and improving assessment, data collection, and modelling. These recommendations could contribute to reliable and policy-relevant assessments of the effectiveness of NPIs during future epidemics.
Giulia de Meijere et al.
Attitudes towards booster, testing and isolation, and their impact on COVID-19 response in winter 2022/2023 in France, Belgium, and Italy: a cross-sectional survey and modelling study
The Lancet, March 2023; doi.org/10.1016/j.lanepe.2023.100614
Abstract
European countries are focusing on testing, isolation, and boosting strategies to counter the 2022/2023 winter surge due to SARS-CoV-2 Omicron subvariants. However, widespread pandemic fatigue and limited compliance potentially undermine mitigation efforts.
Methods
To establish a baseline for interventions, we ran a multicountry survey to assess respondents’ willingness to receive booster vaccination and comply with testing and isolation mandates. Integrating survey and estimated immunity data in a branching process epidemic spreading model, we evaluated the effectiveness and costs of current protocols in France, Belgium, and Italy to manage the winter wave.
Findings
The vast majority of survey participants (N = 4594) was willing to adhere to testing (>91%) and rapid isolation (>88%) across the three countries. Pronounced differences emerged in the declared senior adherence to booster vaccination (73% in France, 94% in Belgium, 86% in Italy). Epidemic model results estimate that testing and isolation protocols would confer significant benefit in reducing transmission (17–24% reduction, from R = 1.6 to R = 1.3 in France and Belgium, to R = 1.2 in Italy) with declared adherence. Achieving a mitigating level similar to the French protocol, the Belgian protocol would require 35% fewer tests (from 1 test to 0.65 test per infected person) and avoid the long isolation periods of the Italian protocol (average of 6 days vs. 11). A cost barrier to test would significantly decrease adherence in France and Belgium, undermining protocols’ effectiveness.
Interpretation
Simpler mandates for isolation may increase awareness and actual compliance, reducing testing costs, without compromising mitigation. High booster vaccination uptake remains key for the control of the winter wave.
A. Koirala et al.
Understanding SARS-CoV-2 Delta and Omicron variant transmission and vaccine impact in schools and child-care settings in Australia: a population-based study
The lancet, March 2023; doi.org/10.1016/j.lanwpc.2023.100736
Abstract
Over 214 million students globally have been affected by school closures during the COVID-19 pandemic. To address knowledge gaps on transmission of SARS-CoV-2 delta (B.1.617.2) and omicron (B.1.1.529) variants in educational settings we examined virus transmission in schools and early childhood education and care settings (ECECs) in New South Wales (NSW), Australia in relation to mitigation measures, including COVID-19 vaccination.
Methods
Secondary transmission from children and adults with laboratory-confirmed SARS-CoV-2 infection who attended a school (n = 3170) or ECECs (n = 5800) while infectious was investigated over two periods: 1) June 16 to September 18, 2021 (delta outbreak), and; 2) October 18 to December 18, 2021 (delta and omicron; schools only). Close contacts of cases underwent 14 days quarantine and SARS-CoV-2 nucleic acid testing. Secondary attack rates (SARs) were calculated and compared with state-wide notification data, school attendance, and vaccination status.
Interpretation
Vaccination reduced SARS-CoV-2 transmission rates in schools, although less so for omicron than delta variants. Despite higher community-based transmission rates, in-school transmission remained low and stable with high attendance, suggesting that community restrictions, rather than school closures, best mitigated COVID-19 impacts.
Yajie Zhu et al.
Effectiveness analysis of multiple epidemic prevention measures in the context of COVID-19 using the SVIRD model and ensemble Kalman filter
Cell, March 2023; doi.org/10.1016/j.heliyon.2023.e14231
Abstract
The ability to accurately forecast the spread of coronavirus disease 2019 (COVID-19) is of great importance to the resumption of societal normality. Existing methods of epidemic forecasting often ignore the comprehensive analysis of multiple epidemic prevention measures. This paper aims to analyze various epidemic prevention measures through a compound framework. Here, a susceptible-vaccinated-infected-recovered-deceased (SVIRD) model is constructed to consider the effects of population mobility among origin and destination, vaccination, and positive retest populations. And we further use real-time observations to correct the model trajectory with the help of data assimilation. Seven prevention measures are used to analyze the short-term trend of active cases. The results of the synthetic scene recommended that four measures—improving the vaccination protection rate (IVPR), reducing the number of contacts per person per day (RNCP), selecting the region with less infected people as origin A (SES-O) and limiting population flow entering from A to B per day (LAIP-OD)—are the most effective in the short-term, with maximum reductions of 75%, 53%, 35% and 31%, respectively, in active cases after 150 days. The results of the real-world experiment with Hong Kong as the origin and Shenzhen as the destination indicate that when the daily vaccination rate increased from 5% to 9.5%, the number of active cases decreased by only 7.35%. The results demonstrate that reducing the number of contacts per person per day after productive life resumes is more effective than increasing vaccination rates.
Slomski A. et al.
Vitamin D supplements don’t reduce Covid-19 risk
JAMA, October 2022; doi:10.1001/jama.2022.15486
Abstract
The trial showed that adults who took oral vitamin D supplements during the SARS-CoV-2 pandemic when vaccine coverage was low, were not protected against COVID-19 or any other acute respiratory tract infections.
Frenk J. et al.
Challenges and opportunities for educating health professionals after the COVID-19 pandemic
Lancet, October 2022; doi.org/10.1016/S0140-6736(22)02092-X
Abstract
In this Health Policy, the authors list institutional and instructional reforms to assess what has happened to health-professional education since the publication of the Lancet Commission and how the COVID-19 pandemic altered the education process.
M. E. Curlin et al.
Omicron neutralizing antibody response following booster vaccination compared with breakthrough infection.
Med, October 2022; doi.org/10.1016/j.medj.2022.09.001
Abstract
The immunity provided by standard vaccine regimens, boosted regimens, and immune responses elicited by vaccination plus natural infection remain incompletely understood. The magnitude, quality, and durability of serological responses, and the likelihood of protection against future SARS-CoV-2 variants following these modes of exposure, are poorly characterized but are essential to the future trajectory of the coronavirus disease 2019 (COVID-19) pandemic.
L. En Wee et al.
Enhanced infection prevention measures including universal n95 usage and daily testing: the impact on SARS-CoV-2 transmission in cohorted hospital cubicles through successive delta and omicron waves
Clinical Infectious Diseases, September 2022; doi.org/10.1093/cid/ciac320
Abstract
In Singapore, extensive infection prevention measures were implemented at onset of the COVID-19 pandemic, including universal N95 usage, mandatory surgical mask use for patients/visitors, visitor restrictions (2/day), employee vaccination programs, and free onsite testing for healthcare workers. The authors would like to share their experience with universal N95 usage and daily testing for coronavirus disease 2019 (COVID-19) cluster-control over a 9-month period, during successive waves attributed to the SARS-CoV-2 Delta and Omicron variants.
G.A. Herman et al.
Efficacy and safety of a single dose of casirivimab and imdevimab for the prevention of COVID-19 over an 8-month period: a randomised, double-blind, placebo-controlled trial
Lancet Infectious Diseases, July 2022; doi.org/10.1016/ S1473-3099(22)00416-9
Abstract
There is an unmet need for COVID-19 prevention in patient populations who have not mounted or are not expected to mount an adequate immune response to complete COVID-19 vaccination. The authors previously reported that a single subcutaneous 1200 mg dose of the monoclonal antibody combination casirivimab and imdevimab (CAS+IMD) prevented symptomatic SARS-CoV-2 infections by 81·4% in generally healthy household contacts of SARS-CoV-2-infected individuals over a 1-month efficacy assessment period. Here they present additional results, including the 7-month follow-up period (months 2–8), providing additional insights about the potential for efficacy in pre-exposure prophylaxis settings.
D.L. Faustman et al.
Multiple BCG vaccinations for the prevention of COVID-19 and other infectious diseases in type 1 diabetes
Cell Rep Med, August 2022; doi: 10.1016/j.xcrm.2022.100728
Abstract
There is a need for safe and effective platform vaccines to protect against coronavirus disease 2019 (COVID-19) and other infectious diseases. In this randomized, double-blinded, placebo-controlled phase 2/3 trial, we evaluate the safety and efficacy of a multi-dose Bacillus Calmette-Guérin (BCG) vaccine for the prevention of COVID-19 and other infectious disease in a COVID-19-unvaccinated, at-risk-community-based cohort. The at-risk population is made of up of adults with type 1 diabetes. We enrolled 144 subjects and randomized 96 to BCG and 48 to placebo. There were no dropouts over the 15-month trial. A cumulative incidence of 12.5% of placebo-treated and 1% of BCG-treated participants meets criteria for confirmed COVID-19, yielding an efficacy of 92%. The BCG group also displayed fewer infectious disease symptoms and lesser severity and fewer infectious disease events per patient, including COVID-19. There were no BCG-related systemic adverse events. BCG's broad-based infection protection suggests that it may provide platform protection against new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants and other pathogens.
M. Borna et al.
A correlational analysis of COVID-19 incidence and mortality and urban determinants of vitamin D status across the London boroughs
Nature Scientific Reports, July 2022; doi.org/10.1038/s41598-022-15664-y
Abstract
One of the biggest challenges of the COVID-19 pandemic is the heterogeneity in disease severity exhibited amongst patients. Among multiple factors, latest studies suggest vitamin D deficiency and pre-existing health conditions to be major contributors to death from COVID-19. It is known that certain urban form attributes can impact sun exposure and vitamin D synthesis. Also, long-term exposure to air pollution can play an independent role in vitamin D deficiency. We conducted a correlational analysis of urban form and air quality in relation to the demographics and COVID-19 incidence and mortality across 32 London boroughs between March 2020 and January 2021. We found total population, number of residents of Asian ethnicity, 4-year average PM10 levels and road length to be positively correlated with COVID-19 cases and deaths. We also found percentage of households with access to total open space to be negatively correlated with COVID-19 deaths. Our findings link COVID-19 incidence and mortality across London with environmental variables linked to vitamin D status. Our study is entirely based on publicly available data and provides a reference framework for further research as more data are gathered and the syndemic dimension of COVID-19 becomes increasingly relevant in connection to health inequalities within large urban areas.
G.A. Herman et al.
Efficacy and safety of a single dose of casirivimab and imdevimab for the prevention of COVID-19 over an 8-month period: a randomised, double-blind, placebo-controlled trial
eco, controllato con placebo
The Lancet Infectious Diseases, July 2022; doi.org/10.1016/S1473-3099(22)00416-9
Abstract
Background
There is an unmet need for COVID-19 prevention in patient populations who have not mounted or are not expected to mount an adequate immune response to complete COVID-19 vaccination. We previously reported that a single subcutaneous 1200 mg dose of the monoclonal antibody combination casirivimab and imdevimab (CAS + IMD) prevented symptomatic SARS-CoV-2 infections by 81·4% in generally healthy household contacts of SARS-CoV-2-infected individuals over a 1-month efficacy assessment period. Here we present additional results, including the 7-month follow-up period (months 2–8), providing additional insights about the potential for efficacy in pre-exposure prophylaxis settings.
Methods
This was a randomised, double-blind, placebo-controlled trial done in the USA, Romania, and Moldova in 2020–2021, before the emergence of omicron (B.1.1.529) and omicron-lineage variants. Uninfected and unvaccinated household contacts of infected individuals, judged by the investigator to be in good health, were randomly assigned (1:1) to receive 1200 mg CAS + IMD or placebo by subcutaneous injection according to a central randomisation scheme provided by an interactive web response system; randomisation was stratified per site by the test results of a local diagnostic assay for SARS-CoV-2 and age group at baseline. COVID-19 vaccines were prohibited before randomisation, but participants were allowed to receive COVID-19 vaccination during the follow-up period. Participants who developed COVID-19 symptoms during the follow-up period underwent RT-PCR testing. Prespecified endpoints included the proportion of previously uninfected and baseline-seronegative participants (seronegative-modified full analysis set) who had RT-PCR-confirmed COVID-19 in the follow-up period (post-hoc for the timepoints of months 2–5 and 6–8 only) and underwent seroconversion (ie, became seropositive, considered a proxy for any SARS-CoV-2 infections [symptomatic and asymptomatic]; prespecified up to day 57, post-hoc for all timepoints thereafter). We also assessed the incidence of treatment-emergent adverse events.
Findings
From July 13, 2020, to Oct 4, 2021, 2317 participants who were RT-PCR-negative for SARS-CoV-2 were randomly assigned, of whom 1683 (841 assigned to CAS + IMD and 842 assigned to placebo) were seronegative at baseline. During the entirety of the 8-month study, CAS + IMD reduced the risk of COVID-19 by 81·2% (nominal p<0·0001) versus placebo (prespecified analysis). During the 7-month follow-up period, protection was greatest during months 2–5, with a 100% relative risk reduction in COVID-19 (nominal p<0·0001; post-hoc analysis). Efficacy waned during months 6–8 (post-hoc analysis). Seroconversion occurred in 38 (4·5%) of 841 participants in the CAS + IMD group and in 181 (21·5%) of 842 in the placebo group during the 8-month study (79·0% relative risk reduction vs placebo; nominal p<0·0001). Six participants in the placebo group were hospitalised due to COVID-19 versus none who received CAS + IMD. Serious treatment-emergent adverse events (including COVID-19) were reported in 24 (1·7%) of 1439 participants receiving CAS + IMD and in 23 (1·6%) of 1428 receiving placebo. Five deaths were reported, none of which were due to COVID-19 or related to the study drugs.
Interpretation
CAS + IMD is not authorised in any US region as of Jan 24, 2022, because data show that CAS + IMD is not active against omicron-lineage variants. In this study, done before the emergence of omicron-lineage variants, a single subcutaneous 1200 mg dose of CAS + IMD protected against COVID-19 for up to 5 months of community exposure to susceptible strains of SARS-CoV-2 in the pre-exposure prophylaxis setting, in addition to the post-exposure prophylaxis setting that was previously shown.
T.D. Ngo
Bad COVID Public Health Messaging Is Blocking Our Path to a ‘New Normal’
Scientific American, June 2022: https://www.scientificamerican.com/article/bad-covid-public-healthmessaging-is-blocking-our-path-to-a-new-normal/
Abstract
The U.S. has no clear vision of how to reach a postpandemic world. Over the past two years, we have developed extraordinary scientific tools for the mitigation, treatment and prevention of COVID. But we’ve stumbled badly in implementing them. Many of these failures happened because our public health messages were not clear about how to use those tools, which include vaccines, masks, tests, antiviral drugs and temporary activity restrictions. The result is confusion among the public that has left us vulnerable to the disease and unable to respond to new and more transmissible variants such as BA.2 and its sublineages, which are infecting a rising number of people across the nation.
E. Arcà et al.
Death by austerity? The impact of cost containment on avoidable mortality in Italy
Health Economics, August 202; doi.org/10.1002/hec.4147
Abstract
Does austerity in health care affect health and healthcare outcomes? We examine the intended and unintended effects of the Italian austerity policy Piano di Rientro aimed at containing the cost of the healthcare sector. Using an instrumental variable strategy that exploits the temporal and geographical variation induced by the policy rollout, we find that the policy was successful in alleviating deficits by reducing expenditure, mainly in the southern regions, but also resulted in a 3% rise in avoidable deaths among both men and women, a reduction in hospital capacity and a rise in south-to-north patient migration. These findings suggest that—even in a high-income country with relatively low avoidable mortality like Italy—spending cuts can hurt survival.
R. Hamad et al.
The role of health care systems in bolstering the social safety net to address health inequities in the wake of the covid-19 pandemic
JAMA, June 2022; doi:10.1001/jama.2022.10160
Abstract
For hundreds of years, US health has been characterized by vast inequities in health achievement across groups. For example, at least since the 1800s, disparities in tuberculosis were known to be associated with overcrowded housing, poor ventilation, and malnutrition. The earliest evaluations of the Framingham Heart Study documented disparities in cardiovascular disease by educational attainment. Today, advantaged groups in the US have a 20-year greater life expectancy than disadvantaged groups, while racial and ethnic minority populations and those with lower income and education (among other types of disadvantage) have a greater burden of disease than more advantaged groups. As the scholarship examining these health outcomes has evolved, it has become clearer that these inequities are caused by foundational social and structural forces, stemming from historical structural conditions that carry to the present day.
P. Marks et al.
COVID-19 Vaccination—Becoming Part of the New Normal
JAMA, May 2022; doi:10.1001/jama.2022.7469
Abstract
As the US emerges from the recent Omicron surge of the COVID-19 pandemic following close to a million deaths in the country attributable to COVID-19, many people are hoping that the worst is over. Widespread vaccine- and infection-induced immunity, combined with the availability of effective therapeutics, could blunt the effects of future outbreaks. Nonetheless, it is time to accept that the presence of SARS-CoV-2, the virus that causes COVID-19, is the new normal. It will likely circulate globally for the foreseeable future, taking its place alongside other common respiratory viruses such as influenza. And it likely will require similar annual consideration for vaccine composition updates in consultation with the US Food and Drug Administration (FDA) Vaccines and Related Biological Products Advisory Committee (VRBPAC). A recent meeting of the VRBPAC on April 6, 2022, resulted in a lively discussion and agreement on many considerations for planning for upcoming approaches to COVID-19 vaccine strain composition decision-making, development, and recommendations.
M.J. Levin et al.
Intramuscular AZD7442 (Tixagevimab–Cilgavimab) for Prevention of Covid-19
N Engl J Med., April; doi: 10.1056/NEJMoa2116620
Abstract
Background: The monoclonal-antibody combination AZD7442 is composed of tixagevimab and cilgavimab, two neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that have an extended half-life and have been shown to have prophylactic and therapeutic effects in animal models. Pharmacokinetic data in humans indicate that AZD7442 has an extended half-life of approximately 90 days.
Methods: In an ongoing phase 3 trial, we enrolled adults (≥18 years of age) who had an increased risk of an inadequate response to vaccination against coronavirus disease 2019 (Covid-19), an increased risk of exposure to SARS-CoV-2, or both. Participants were randomly assigned in a 2:1 ratio to receive a single dose (two consecutive intramuscular injections, one containing tixagevimab and the other containing cilgavimab) of either 300 mg of AZD7442 or saline placebo, and they were followed for up to 183 days in the primary analysis. The primary safety end point was the incidence of adverse events after a single dose of AZD7442. The primary efficacy end point was symptomatic Covid-19 (SARS-CoV-2 infection confirmed by means of reverse-transcriptase-polymerase-chain-reaction assay) occurring after administration of AZD7442 or placebo and on or before day 183.
Results: A total of 5197 participants underwent randomization and received one dose of AZD7442 or placebo (3460 in the AZD7442 group and 1737 in the placebo group). The primary analysis was conducted after 30% of the participants had become aware of their randomized assignment. In total, 1221 of 3461 participants (35.3%) in the AZD7442 group and 593 of 1736 participants (34.2%) in the placebo group reported having at least one adverse event, most of which were mild or moderate in severity. Symptomatic Covid-19 occurred in 8 of 3441 participants (0.2%) in the AZD7442 group and in 17 of 1731 participants (1.0%) in the placebo group (relative risk reduction, 76.7%; 95% confidence interval [CI], 46.0 to 90.0; P<0.001); extended follow-up at a median of 6 months showed a relative risk reduction of 82.8% (95% CI, 65.8 to 91.4). Five cases of severe or critical Covid-19 and two Covid-19-related deaths occurred, all in the placebo group.
Conclusions: A single dose of AZD7442 had efficacy for the prevention of Covid-19, without evident safety concerns. (Funded by AstraZeneca and the U.S. government; PROVENT ClinicalTrials.gov number, NCT04625725.).
S. Vardhana et al.
Understanding T-cell responses to COVID-19 is essential for informing public health strategies
Science Immunology, March 2022; doi: 10.1126/sciimmunol.abo1303
Abstract
Durable T-cell responses to SARS-CoV-2 antigens after infection or vaccination improve immune-mediated viral clearance. To date, population-based surveys of COVID-19 adaptive immunity have focused on testing for IgG antibodies that bind spike protein and/or neutralize the virus. Deployment of existing methods for measuring T-cell immunity could provide a more complete profile of immune status, informing public health policies and interventions.
Bartsch S.M. et al.
Maintaining face mask use before and after achieving different COVID-19 vaccination coverage levels: a modelling study
The Lancet, https://www.thelancet.com/action/showPdf?pii=S2468-2667%2822%2900040-8
CONTENUTO E COMMENTO : Studio con modello-simulato computazionale finalizzato a comparare cosa accade se le mascherine vengono utilizzate vs. non utilizzate in attesa del raggiungimento di differenti livelli di copertura vaccinale della popolazione considerati nello studio (70-90%). La simulazione ha mostrato che indossare la mascherina, in tutti i contesti analizzati, risultava conveniente in termini di costi e in molti casi portava ad un risparmio sia per la società ed i singoli individui che per le assicurazioni sanitarie. Tali benefici sono stati riscontrati calcolando come costo unitario della mascherina 1.25 dollari al massimo. In tutti gli scenari è risultato conveniente indossare tale dspositivo di protezione anche dalle 2 alle 10 settimane dopo il raggiungimento della copertura vaccinale considerata, con un prolungamento di tale periodo se il target di è stato raggiunto nella stagione invernale. Tutti i fattori che possono incrementare la trasmissibilità del virus (nuove varianti, riduzione dell’efficacia del vaccino) non fanno che aumentare il cost-saving e il cost-effectiveness derivante dal mantenimento di tale DPI. Ovviamente essendo un modello costituisce una semplificazione della realtà, concedendo comunque informazioni utili per una migliore organizzazione della società nella gestione della pandemia.
Yang Y; et al.
Longitudinal analysis of antibody dynamics in COVID-19 convalescents reveals neutralizing responses up to 16 months after infection
Nature Microbiology,
https://www.nature.com/articles/s41564-021-01051-2
CONTENUTO E COMMENTO : Studio esplorante le dinamiche della risposta anticoprale in una coorte di 214 pazienti sopravvissuti all’infezione da SARS-CoV2, non ri-esposti al virus o alla vaccinazione, in un periodo di tempo compreso tra 1 e 480 giorni dall’esordio dei sintomi.
In questo studio, il picco di risposta anticorpale è stato raggiunto al giorno 120 dall’esordio dei sintomi, per poi andare incontro a una progressiva riduzione. Tuttavia, nonostante tale declino, i ricercatori hanno osservato una persistente attività neutralizzante di tipo IgG fino a 480 giorni dopo l’esordio dei sintomi, rilevata sia nei casi di infezioni lievi (85.6%), sia nei casi di infezione asintomatica (50%). L’attività neutralizzante di tali anticorpi si è rivelata però rignificativamente inferiore nei confronti delle varianti Beta, Delta e Mu.
Zou J.; et al.
Neutralization against Omicron SARS-CoV-2 from previous non-Omicron infection
Nature Communications,
https://www.nature.com/articles/s41467-022-28544-w
CONTENUTO E COMMENTO: Studio in vitro, analizzante l’attività neutralizzante degli anticorpi prodotti in risposta a un’infezione da variante non Omicron nei confronti della proteina Spike caratteristica della variante Omicron, sintetizzata in laboratorio e inserendola nel DNA della variante USA-WA1/2020, isolata a gennaio 2020. In questo modo, sono stati determinati i titoli anticorpali neutralizzanti, definiti come la massima diluizione in grado di neutralizzare il 50% dei virioni infettivi, in campioni di siero di pazienti convalescenti da COVID-19, raccolti a distanza di 1 – 6 mesi dalla diagnosi.
Nel corso di tale periodo di tempo, i titoli neutralizzanti contro USA-WA1/2020 sono scesi da 601 a 142, mentre i titoli neutralizzanti contro Omicron sono rimasti stabilmente bassi, tra 38 e 32. Tale risultato dimostra la bassa reattività anticorpale crociata, da una precedente infezione da variante non-Omicron, nei confronti di Omicron.
ECDC Technical Report
Considerations for the use of face masks in the community in the context of the SARS-CoV-2 Omicron variant of concern
https://www.ecdc.europa.eu/en/publications-data/using-face-masks-community-reducing-covid-19-transmission
CONTENUTO E COMMENTO : Revisione della letteratura sull’efficacia delle mascherine a livello di comunità, in considerazione della diffusione della variante Omicron.
Tale documento conclude che una policy di utilizzo della mascherina è raccomandato in tutti i contesti in cui si ha un’evidenza di circolazione virale a livello della comunità. Un’opzione alternativa potrebbe essere quella di utilizzare la mascherina in contesti in cui si ha una elevata concentrazione di individui fragili e/o particolarmente esposti allo sviluppo di COVID severo, come le case di riposo. Il documento ricorda inoltre che le mascherine, per essere realmente efficaci, devono essere utilizzate correttamente, ricoprendo interamente il volto dalla piramide nasale al mento. Inoltre, le mascherine filtranti tipo FFP2/3 è probabile che siano più efficaci, nel ridurre la diffusione del virus, rispetto alle mascherine chirurgiche o altri tipi di mascherine.
Olivera Mesa D.; et al.
Modelling the impact of vaccine hesitancy in prolonging the need for Non-Pharmaceutical Interventions to control the COVID-19 pandemic
Communications Medicine, https://www.nature.com/articles/s43856-022-00075-x
CONTENUTO E COMMENTO : Studio esplorante il l’impatto dell’esitazione vaccinale nel prolungamento degli interventi non farmacologici di controllo della pandemia. Tale analisi, effettuata costruendo un modello matematico con dati epidemiologici e dati di esitazione vaccinale estratti da survey di popolazione, conclude che, nei paesi coi più alti tassi di esitazione vaccinale, in un periodo di tempo di 2 anni e in un contesto di generale rilassamento delle restrizioni, la mortalità COVID-relata potrebbe essere fino a 7.6 volte maggiore rispetto a paesi con livelli ideali di aderenza vaccinale.
Questo modello sottolinea pertanto quanto, per quanto sottoporsi a vaccinazione sia una scelta individuale, l’esitazione vaccinale ha un impatto significativo sulla traiettoria della pandemia, in grado di mettere in difficoltà gli sforzi messi in atto fino ad ora per contrastare la COVID-19.
Klompas, M.; Karan, A.
Preventing SARS-CoV-2 Transmission in Health Care Settings in the Context of the Omicron Variant
JAMA, file:///C:/Users/00122705/Downloads/jama_klompas_2022_vp_220006_1643401941.87023.pdf
CONTENUTO E COMMENTO: Il lavoro analizza separatamente tre misure fondamentali per ridurre la diffusione della variante Omicron all’interno degli ospedali, evento che purtroppo pone a rischio le strutture di focolai all’interno dei reparti nonchè di numerose e improvvise assenze da parte del personale sanitario. Le misure analizzate sono :
- il booster negli operatori ;
- lo screening frequente degli asintomatici (Il rischio stimato di infezione per un paziente ricoverato in una stanza condivisa con un vettore SARS-CoV-2 positivo occulto va dal 30% al 40%).
-Le mascherine N95 (l’equivalente certificazione americana della mascherina FFP2 europea).
