Project description:Purpose: This study aims to characterize the early innate and adaptive responses induced by SARS-CoV-2 infection in children and adults over time up to 8 weeks post symptoms onset (POS). We report the gene signature of COVID-19 over the course of the disease in both age groups. The kinetic of infection was divided in 5-time intervals according to the calculated days POS: interval 1 (0-5), interval 2 (6-14), interval 3 (15-22), interval 4 (23-35), and interval 5 (36-81). Methods: RNA extraction was performed automatically via the PAXgene Blood miRNA Kit and the QIAcube instrument (Qiagen) following the manufacturer’s protocol. RNA concentration and quality were assessed by using the Qubit instrument (Invitrogen) and the Agilent 2100 Bioanalyzer, respectively. The Stranded Total RNA Ribo-Zero Plus kit from Illumina was used for the library preparation with 100 ng of total RNA as input. Library molarity and quality were assessed with the Qubit and Tapestation using a DNA High sensitivity chip (Agilent Technologies). Libraries were pooled at 2 nM for clustering and sequenced on an Illumina HiSeq 4000 sequencer for a minimum of 30 million single-end 100 reads per sample. Main results: (I) we observed an antiviral-IFN-signature and innate-cell-activation within the first 5 days post symptoms onset (POS), while genes associated with CD4 T-cell responses, plasma cells and immunoglobulin were upregulated in both age groups during the first two weeks POS, indicative of SARS-CoV-2-specific adaptive immune responses; (II) in adults, genes associated with IFN antiviral responses and activated dendritic cells were maintained during the second week of disease, and subsided only after 14 days. By contrast, those transcriptome changes subsided already after 5 days in children.
Project description:At this stage in the COVID-19 pandemic, most infections are 'breakthrough' infections that occur in individuals with prior immunity to SARS-CoV-2 through infection or vaccination. Understanding both innate and adaptive immune induction in the setting of breakthrough infection is critical to refining vaccine strategies to ensure long-term efficacy against emerging variants, yet existing studies have primarily focused on adaptive immune responses. Here, we performed single-cell transcriptomic, proteomic, and functional profiling of innate and adaptive immunity during primary and breakthrough COVID-19 infections by comparing immune responses between unvaccinated and vaccinated individuals during the SARS-CoV-2 Delta wave. Breakthrough infections were characterized by a significantly less activated transcriptomic profile in CD56dim NK cells and monocytes, with induction of pathways limiting NK cell proliferation and monocyte migratory potential. Furthermore, we observed a female-specific trend of increased transcriptomic activation of CD16+ monocytes and type-2 conventional dendritic cells (cDC2s) during breakthrough infections. Despite these differences, antibody-dependent cellular cytotoxicity responses were similar between breakthrough and primary infection groups. These insights suggest that prior vaccination prevents overactivation of innate immune responses during breakthrough infections with discernible sex-specific patterns and underscore the potential of harnessing vaccines in mitigating pathologic immune responses resulting from overactivation.
Project description:BACKGROUND. Coronavirus disease 2019 (COVID-19) is more benign in children compared with adults for unknown reasons. This contrasts with other respiratory viruses where disease manifestations are often more severe in children. We hypothesize that a more robust early innate immune response to SARS coronavirus 2 (SARS-CoV-2) protects against severe disease. METHODS. Clinical outcomes, SARS-CoV-2 viral copies, and cellular gene expression were compared in nasopharyngeal swabs obtained at the time of presentation to the emergency department from 12 children and 27 adults using bulk RNA sequencing and quantitative reverse-transcription PCR. Total protein, cytokines, and anti–SARS-CoV-2 IgG and IgA were quantified in nasal fluid. We used a subset of 21 samples for RNAseq analysis. RESULTS. SARS-CoV-2 copies, angiotensin-converting enzyme 2 (ACE2), and TMPRSS2 gene expression were similar in children and adults, but children displayed higher expression of genes associated with IFN signaling, NLRP3 inflammasome, and other innate pathways. Higher levels of IFN-α2, IFN-γ, IP-10, IL-8, and IL-1β protein were detected in nasal fluid in children versus adults. Children also expressed higher levels of genes associated with immune cells, whereas expression of those associated with epithelial cells did not differ in children versus adults. Anti–SARS-CoV-2 IgA and IgG were detected at similar levels in nasal fluid from both groups. None of the children required supplemental oxygen, whereas 7 adults did (P = 0.03); 4 adults died. CONCLUSION. These findings provide direct evidence of a more vigorous early mucosal immune response in children compared with adults and suggest that this contributes to favorable clinical outcomes.
Project description:BackgroundPaediatric patients with autoimmune rheumatic diseases (pARD) are often immunocompromised because of the disease and/or the therapy they receive. At the beginning of COVID-19 pandemic there was a great concern about the possibility of severe SARS-CoV-2 infection in these patients. The best method of protection is vaccination, so as soon as vaccine was licenced, we aimed to vaccinate them. Data on disease relapse rate after COVID-19 infection and vaccination are scarce, but they play important role in everyday clinical decisions.MethodsThe aim of this study was to determine the relapse rate of autoimmune rheumatic disease (ARD) after COVID-19 infection and vaccination. Data on demographic, diagnosis, disease activity, therapy, clinical presentation of the infection and serology were collected from pARD who had COVID-19 and from pARD who were vaccinated against COVID-19, from March 2020 to April 2022. All vaccinated patients received two doses of the BNT162b2 BioNTech vaccine, on average, 3.7 (S.D.=1.4) weeks apart. Activity of the ARD was followed prospectively. Relapse was defined as a worsening of the ARD in a time frame of 8 weeks after infection or vaccination. For statistical analysis, Fisher's exact test and Mann-Whitney U test were used.ResultsWe collected data from 115 pARD, which we divided into two groups. We included 92 pARD after infection and 47 after vaccination, with 24 in both groups (they were infected before/after vaccination). In 92 pARD we registered 103 SARS-CoV-2 infections. Infection was asymptomatic in 14%, mild in 67% and moderate in 18%, 1% required hospitalization; 10% had a relapse of ARD after infection and 6% after vaccination. There was a trend towards higher disease relapse rate after infection compared to vaccination, but the difference was not statistically significant (p = 0.76). No statistically significant difference was detected in the relapse rate depending on the clinical presentation of the infection (p = 0.25) or the severity of the clinical presentation of COVID-19 between vaccinated and unvaccinated pARD (p = 0.31).ConclusionsThere is a trend towards a higher relapse rate in pARD after infection compared to vaccination and connection between the severity of COVID-19 and vaccination status is plausible. Our results were, however, not statistically significant.
Project description:RNA was extracted from whole blood of subjects collected in Tempus tubes prior to COVID-19 mRNA booster vaccination. D01 and D21 correspond to samples collected at pre-dose 1 and pre-dose 2 respectively. RNA was also extracted from blood collected at indicated time points post-vaccination. DB1, DB2, DB4 and DB7 correspond to booster day 1 (pre-booster), booster day 2, booster day 4 and booster day 7 respectively. The case subject experienced cardiac complication following mRNA booster vaccination. We performed gene expression analysis of case versus controls over time.
Project description:ObjectiveTo evaluate whether COVID-19 vaccination status or mode of anesthesia modified the temporal harms associated with surgery following coronavirus disease-2019 (COVID-19) infection.BackgroundSurgery shortly after COVID-19 infection is associated with higher rates of complications, leading to recommendations to delay surgery following COVID-19 infection when possible. However, prior studies were based on populations with low or no prevalence of vaccination.MethodsA retrospective cohort study of patients who underwent scheduled surgery in a health system from January 1, 2018 to February 28, 2022 (N=228,913) was performed. Patients were grouped by time of surgery relative to COVID-19 test positivity: 0 to 4 weeks after COVID-19 ("early post-COVID-19"), 4 to 8 weeks after COVID-19 ("mid post-COVID-19"), >8 weeks after COVID-19 ("late post-COVID-19"), surgery at least 30 days before subsequent COVID-19 ("pre-COVID-19"), and surgery with no prior or subsequent test positivity for COVID-19.ResultsAmong patients who were not fully vaccinated at the time of COVID-19 infection, the adjusted rate of perioperative complications for the early post-COVID-19 group was significantly higher than for the pre-COVID-19 group (relative risk: 1.55; P =0.05). No significantly higher risk was identified between these groups for patients who were fully vaccinated (0.66; P =1.00), or for patients who were not fully vaccinated and underwent surgery without general anesthesia (0.52; P =0.83).ConclusionsSurgery shortly following COVID-19 infection was not associated with higher risks among fully vaccinated patients or among patients who underwent surgery without general anesthesia. Further research will be valuable to understand additional factors that modify perioperative risks associated with prior COVID-19 infection.
Project description:The SARS-CoV-2 Delta (B.1.617.2) variant is capable of infecting vaccinated persons. An open question remains as to whether deficiencies in specific vaccine-elicited immune responses result in susceptibility to vaccine breakthrough infection. We investigated 55 vaccine breakthrough infection cases (mostly Delta) in Singapore, comparing them against 86 vaccinated close contacts who did not contract infection. Vaccine breakthrough cases showed lower memory B cell frequencies against SARS-CoV-2 receptor binding domain (RBD). Compared to plasma antibodies, antibodies secreted by memory B cells retained a higher fraction of neutralizing properties against the Delta variant. Inflammatory cytokines including IL-1β and TNF were lower in vaccine breakthrough infections than primary infection of similar disease severity, underscoring the usefulness of vaccination in preventing inflammation. This report highlights the importance of memory B cells against vaccine breakthrough, and suggests that lower memory B cell levels may be a correlate of risk for Delta vaccine breakthrough infection.
Project description:Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative respiratory pathogen responsible for coronavirus disease 2019 (COVID-19). In 2020, the power of open science was visible to all, as novel vaccinology led to rapid establishment of vaccine clinical trials, and subsequent authorization of SARS-CoV-2 at an unprecedented pace. This evoked rapid deployment of SARS-CoV-2 vaccines and booster doses to keep with the ever-changing landscape of SARS-CoV-2. In this review, we provide an overview of vaccine efficacy studies, which have been well characterized in healthy individuals. Nevertheless, vaccine efficacy within the immunosuppressed is less well characterized, as these individuals were omitted from initial efficacy studies. Consequently, vaccine-induced responses in this group are relatively unknown. Currently, limited evidence investigating vaccine efficacy within the immunosuppressed is available. Here, we provide an overview of SARS-CoV-2 infection and associated pathogenesis. Furthermore, we undertake a critical analysis of observed vaccine responses from clinical studies, conducted in healthy and immunosuppressed populations. Whilst vaccine deployment has curbed mortality, there are significant challenges that lie ahead. This includes correlating vaccine responses with protective immunity and ensuring that global vaccine equity is met.
Project description:ImportanceA significant proportion of COVID-19 transmission occurs silently during the presymptomatic and asymptomatic stages of infection. Children, although important drivers of silent transmission, are not included in the current COVID-19 vaccination campaigns.ObjectiveTo estimate the benefits of identifying silent infections among children as a proxy for their vaccination.Design, setting, and participantsThis study used an age-structured disease transmission model, parameterized with census data and estimates from published literature, to simulate the estimated synergistic effect of interventions in reducing attack rates during the course of 1 year among a synthetic population representative of the US demographic composition. The population included 6 age groups of 0 to 4, 5 to 10, 11 to 18, 19 to 49, 50 to 64, and 65 years or older based on US census data. Data were analyzed from December 12, 2020, to February 26, 2021.ExposuresIn addition to the isolation of symptomatic cases within 24 hours of symptom onset, vaccination of adults was implemented to reach a 40% to 60% coverage during 1 year with an efficacy of 95% against symptomatic and severe COVID-19.Main outcomes and measuresThe combinations of proportion and speed for detecting silent infections among children that would suppress future attack rates to less than 5%.ResultsIn the base-case scenarios with an effective reproduction number Re = 1.2, a targeted approach that identifies 11% of silent infections among children within 2 days and 14% within 3 days after infection would bring attack rates to less than 5% with 40% vaccination coverage of adults. If silent infections among children remained undetected, achieving the same attack rates would require an unrealistically high vaccination coverage (≥81%) of this age group, in addition to 40% vaccination coverage of adults. The estimated effect of identifying silent infections was robust in sensitivity analyses with respect to vaccine efficacy against infection and reduced susceptibility of children to infection.Conclusions and relevanceIn this simulation modeling study of a synthetic US population, in the absence of vaccine availability for children, a targeted approach to rapidly identify silent COVID-19 infections in this age group was estimated to significantly mitigate disease burden. These findings suggest that without measures to interrupt transmission chains from silent infections, vaccination of adults is unlikely to contain the outbreaks in the near term.