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1.
Front Immunol ; 13: 1011084, 2022.
Article in English | MEDLINE | ID: covidwho-2312677

ABSTRACT

Background: Prognostic markers for COVID-19 disease outcome are currently lacking. Plasma gelsolin (pGSN) is an actin-binding protein and an innate immune marker involved in disease pathogenesis and viral infections. Here, we demonstrate the utility of pGSN as a prognostic marker for COVID-19 disease outcome; a test performance that is significantly improved when combined with cytokines and antibodies compared to other conventional markers such as CRP and ferritin. Methods: Blood samples were longitudinally collected from hospitalized COVID-19 patients as well as COVID-19 negative controls and the levels of pGSN in µg/mL, cytokines and anti- SARS-CoV-2 spike protein antibodies assayed. Mean ± SEM values were correlated with clinical parameters to develop a prognostic platform. Results: pGSN levels were significantly reduced in COVID-19 patients compared to healthy individuals. Additionally, pGSN levels combined with plasma IL-6, IP-10 and M-CSF significantly distinguished COVID-19 patients from healthy individuals. While pGSN and anti-spike IgG titers together strongly predict COVID-19 severity and death, the combination of pGSN and IL-6 was a significant predictor of milder disease and favorable outcomes. Conclusion: Taken together, these findings suggest that multi-parameter analysis of pGSN, cytokines and antibodies could predict COVID-19 hospitalization outcomes with greater certainty compared with conventional clinical laboratory markers such as CRP and ferritin. This research will inform and improve clinical management and health system interventions in response to SARS-CoV-2 infection.


Subject(s)
COVID-19 , Gelsolin , Biomarkers , Chemokine CXCL10 , Cytokines , Ferritins , Hospitalization , Humans , Immunoglobulin G , Interleukin-6 , Macrophage Colony-Stimulating Factor , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
2.
J Assoc Med Microbiol Infect Dis Can ; 8(1): 75-84, 2023 Mar.
Article in English | MEDLINE | ID: covidwho-2279262

ABSTRACT

The SARS-CoV-2 pandemic highlighted the need for rapid, collaborative, and population-centric research to define health impact, develop health care policies and establish reliable diagnostic and surveillance tests. Critical for these objectives were in-depth clinical data collected in standardized fashion and large numbers of various types of human samples prior and post-viral encounter. As the pandemic evolved with the emergence of new variants of concern (VOCs), access to samples and data from infected and vaccinated individuals were needed to monitor immune durability, the possibility of increased transmissibility and virulence, and vaccine protection against new and emerging VOCs. Therefore, essential to the pandemic response is a strong laboratory and data research component, supported by effective biobanking and data sharing. Critically important to the speed of the research response is the rapid access to biobanked samples. To address critical challenges brought to light by the pandemic, the Coronavirus Variants Rapid Response Network (CoVaRR-Net), funded by the Canadian Institutes of Health Research, was established to coordinate research efforts to provide rapid evidence-based responses to emerging VOCs. The purpose of this paper is to introduce the CoVaRR-Net Biobank and define its contribution to pandemic preparedness.


La pandémie de SRAS-CoV-2 a fait ressortir la nécessité de réaliser des recherches rapides, coopératives et populationnelles pour en définir les effets sur la santé, promulguer des politiques sanitaires et établir des tests diagnostiques et des tests de surveillance fiables. Pour réaliser ces objectifs, il était essentiel de colliger des données cliniques approfondies d'une manière standardisée et d'amasser un grand nombre de divers types d'échantillons humains avant et après le contact viral. Lorsque la pandémie a évolué par l'émergence de nouveaux variants préoccupants (VOC), il est devenu nécessaire d'accéder à des échantillons et à des données de personnes infectées et vaccinées pour surveiller la durabilité de l'immunité, la possibilité d'une transmissibilité et d'une virulence accrues et la protection conférée par les vaccins contre les VOC nouveaux et émergents. Ainsi, il est essentiel de disposer d'un vigoureux volet de recherches de laboratoire et de recherches à partir de données pour répondre à la pandémie, soutenu par une mise en biobanque et un partage des données efficaces. Pour assurer une réponse rapide par la recherche, il est tout aussi important d'accéder rapidement aux échantillons mis en biobanque. Afin de relever les défis cruciaux soulevés par la pandémie, le Coronavirus Variants Rapid Response Network (réseau de réponse rapide aux variants du coronavirus; CoVaRR-Net), financé par les Instituts de recherche en santé du Canada, a été créé pour coordonner les efforts de recherche afin de fournir des réponses rapides fondées sur des données probantes aux VOC en émergence. Le présent article vise à présenter la Biobanque CoVaRR-Net et à en définir la contribution à la préparation aux pandémies.

3.
Viruses ; 15(2)2023 02 19.
Article in English | MEDLINE | ID: covidwho-2238514

ABSTRACT

People living with HIV (PLWH) may be at risk for poor immunogenicity to certain vaccines, including the ability to develop immunological memory. Here, we assessed T-cell immunogenicity following three SARS-CoV-2 vaccine doses in PLWH versus uninfected controls. Blood was collected from 38 PLWH on antiretroviral therapy and 24 age-matched HIV-negative controls, pre-vaccination and after 1st/2nd/3rd dose of SARS-CoV-2 vaccines, without prior SARS-CoV-2 infection. Flow cytometry was used to assess ex vivo T-cell immunophenotypes and intracellular Tumor necrosis factor (TNF)-α/interferon(IFN)-γ/interleukin(IL)-2 following SARS-CoV-2-Spike-peptide stimulation. Comparisons were made using Wilcoxon signed-rank test for paired variables and Mann-Whitney for unpaired. In PLWH, Spike-specific CD4 T-cell frequencies plateaued post-2nd dose, with no significant differences in polyfunctional SARS-CoV-2-specific T-cell proportions between PLWH and uninfected controls post-3rd dose. PLWH had higher frequencies of TNFα+CD4 T-cells and lower frequencies of IFNγ+CD8 T-cells than seronegative participants post-3rd dose. Regardless of HIV status, an increase in naive, regulatory, and PD1+ T-cell frequencies was observed post-3rd dose. In summary, two doses of SARS-CoV-2 vaccine induced a robust T-cell immune response in PLWH, which was maintained after the 3rd dose, with no significant differences in polyfunctional SARS-CoV-2-specific T-cell proportions between PLWH and uninfected controls post-3rd dose.


Subject(s)
COVID-19 , HIV Infections , T-Lymphocytes , Humans , CD4-Positive T-Lymphocytes , COVID-19/prevention & control , COVID-19 Vaccines , HIV Infections/drug therapy , SARS-CoV-2 , Tumor Necrosis Factor-alpha , T-Lymphocytes/immunology
4.
AIDS Behav ; 27(8): 2669-2680, 2023 Aug.
Article in English | MEDLINE | ID: covidwho-2229100

ABSTRACT

Understanding the roots of Covid-19 vaccine hesitancy in at-risk groups, such as persons living with HIV (PLWH), is of utmost importance. We developed a modified Vaccine Hesitancy Scale (VHS) questionnaire using items from the National Advisory Committee on Immunization Acceptability Matrix. To examine factors associated with receiving COVID-19 vaccine and the link between vaccine attitudes and beliefs with vaccine behavior, PLWH were recruited via social media and community-based organizations (February-May 2022). Descriptive statistics were used to summarize results. Total VHS score was generated by adding Likert scale scores and linear regression models used to compare results between participants who received or did not receive COVID-19 vaccines. Logistic regression models were used to identify factors associated with vaccine uptake. A total of 246 PLWH indicated whether they received a COVID-19 vaccine. 89% received ≥ 1 dose. Mean total VHS(SD) for persons having received ≥ 1 COVID-19 vaccine was 17.8(6.2) vs. 35.4(9.4) for participants not having received any COVID-19 vaccine. Persons who received ≥ 1 dose were significantly older than those who had not received any (48.4 ± 13.8 vs. 34.0 ± 7.7 years, p < 0.0001). The majority of participants considered COVID-19 vaccination important for their health(81.3%) and the health of others(84.4%). Multivariate logistic regression revealed the odds of taking ≥ 1dose were increased 2.4-fold [95% CI 1.6, 3.5] with each increase in age of 10 years (p < 0.0001). Sex and ethnicity were not different between groups. In conclusion, PLWH accept COVID-19 vaccines for both altruistic and individual reasons. With evolving recommendations and increasing numbers of booster vaccines, we must re-examine the needs of PLWH regularly.


Subject(s)
COVID-19 , HIV Infections , Humans , Child , COVID-19 Vaccines , COVID-19/epidemiology , COVID-19/prevention & control , Canada/epidemiology , HIV Infections/epidemiology , HIV Infections/prevention & control , Ethnicity , Vaccination
5.
Influenza Other Respir Viruses ; 2022 Nov 11.
Article in English | MEDLINE | ID: covidwho-2230892

ABSTRACT

BACKGROUND: Measures introduced during the COVID-19 pandemic intended to address the spread of SARS-CoV-2 may also influence the incidence of other common seasonal respiratory viruses (SRV). This evaluation reports laboratory-confirmed cases of common SRV in a well-defined region of central Canada to address this issue. METHODS: Surveillance data for common non-SARS-CoV-2 SRV in Ottawa, Canada, was provided by the Eastern Ontario Regional Laboratory Association (EORLA) reference virology lab. Weekly reports of the number of positive tests and the proportion that yielded positive results were analyzed from August 26, 2018, to January 2, 2022. RESULTS: A drastic reduction in influenza and other common SRV was observed during the 2020-2021 influenza season in the Ottawa region. Influenza was virtually undetected post-SARS-CoV-2 emergence. Rhinoviruses and enteroviruses were the only viruses that remained relatively unaffected during this period. CONCLUSIONS: We speculated that the introduction of nonpharmaceutical measures including masking to prevent SARS-CoV-2 transmission contributed to the near absence of SRV in the Ottawa region. These measures should remain a key component in addressing spikes in SRV activity and future pandemics.

6.
Int J Infect Dis ; 2022 Nov 30.
Article in English | MEDLINE | ID: covidwho-2230072

ABSTRACT

BACKGROUND: We estimated the effectiveness of COVID-19 vaccines against laboratory-confirmed SARS-CoV-2 infection among people living with HIV (PLWH) and compared estimates with a matched HIV-negative cohort. METHOD: We used the British Columbia COVID-19 Cohort, a population-based data platform which integrates COVID-19 data on SARS-CoV-2 tests, laboratory-confirmed cases, and immunizations with provincial health services data. Vaccine effectiveness (VE) was estimated with a test-negative design using multivariable logistic regression. RESULTS: Adjusted VE against SARS-CoV-2 infection was 79.2% (52.5, 90.9%) 7-59 days after two doses, rising to 91.6% (75.2, 97.2%) between 60-89 days. VE was preserved four to six months following receipt of 2 doses after which slight waning was observed (72.7% [39.1, 87.8%]). In the matched cohort (n=375 043), VE peaked at 91.0% (90.5, 91.5%) 7-59 days after 2 doses and was sustained for up to four months after which evidence of waning was observed, dropping to 83.8% (82.9, 84.7%) between four to six months. CONCLUSION: Receipt of two COVID-19 vaccines doses was effective against SARS-CoV-2 infection among PLWH pre-Omicron. VE estimates appeared to peak later in PLWH compared to the matched HIV-negative cohort and the degree of waning was relatively quicker in PLWH; however, overall estimates were comparable in both populations.

7.
Clinical and Investigative Medicine (Online) ; 45(4):E11-E15, 2022.
Article in English | ProQuest Central | ID: covidwho-2205369

ABSTRACT

Purpose: There is a need for effective and affordable treatments that achieve hepatitis B virus (HBV) functional cure and prevent long-term complications. The use of immune-modulators combined with HBV antivirals is a promising therapeutic strategy to achieve these goals. Based on ribavirin (RBV) monotherapy data, we hypothesized that RBV could improve virological responses when used in combination with tenofovir. Methods: In this randomized, open label, controlled pilot trial, we evaluated RBV (n=4) dosed for the initial 24 weeks of treatment versus no RBV (n=4) in tenofovir recipients dosed over 48 weeks. Results: Although well tolerated and safe in combination with tenofovir, RBV demonstrated no beneficial effects on virologic, biochemical or immunological markers of chronic HBV infection over 48 weeks of serial evaluation. Conclusions: Our data does not suggest a HBV-specific immunomodulatory effect or an impact of RBV on HBV virological and antigen suppression.

8.
AIDS ; 37(1): F1-F10, 2023 01 01.
Article in English | MEDLINE | ID: covidwho-2152274

ABSTRACT

OBJECTIVES: Many vaccines require higher/additional doses or adjuvants to provide adequate protection for people with HIV (PWH). Our objective was to compare COVID-19 vaccine immunogenicity in PWH to HIV-negative individuals. DESIGN: In a Canadian multi-center prospective, observational cohort of PWH receiving at least two COVID-19 vaccinations, we measured vaccine-induced immunity at 3 and 6 months post 2nd and 1-month post 3rd doses. METHODS: The primary outcome was the percentage of PWH mounting vaccine-induced immunity [co-positivity for anti-IgG against SARS-CoV2 Spike(S) and receptor-binding domain proteins] 6 months post 2nd dose. Univariable and multivariable logistic regressions were used to compare COVID-19-specific immune responses between groups and within subgroups. RESULTS: Data from 294 PWH and 267 controls were analyzed. Immunogenicity was achieved in over 90% at each time point in both groups. The proportions of participants achieving comparable anti-receptor-binding domain levels were similar between the group at each time point. Anti-S IgG levels were similar by group at month 3 post 2nd dose and 1-month post 3rd dose. A lower proportion of PWH vs. controls maintained vaccine-induced anti-S IgG immunity 6 months post 2nd dose [92% vs. 99%; odds ratio: 0.14 (95% confidence interval: 0.03, 0.80; P = 0.027)]. In multivariable analyses, neither age, immune non-response, multimorbidity, sex, vaccine type, or timing between doses were associated with reduced IgG response. CONCLUSION: Vaccine-induced IgG was elicited in the vast majority of PWH and was overall similar between groups. A slightly lower proportion of PWH vs. controls maintained vaccine-induced anti-S IgG immunity 6 months post 2nd dose demonstrating the importance of timely boosting in this population.


Subject(s)
AIDS Vaccines , COVID-19 , HIV Infections , Humans , COVID-19 Vaccines , Immunogenicity, Vaccine , Prospective Studies , RNA, Viral , COVID-19/prevention & control , Canada , SARS-CoV-2 , Antibodies
9.
AIDS ; 36(15): F17-F26, 2022 12 01.
Article in English | MEDLINE | ID: covidwho-2116555

ABSTRACT

OBJECTIVE: People with HIV were underrepresented in coronavirus disease 2019 (COVID-19) vaccine clinical trials. We estimated vaccine effectiveness (VE) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection for the BNT162b2, mRNA-1273, and ChAdOx1 vaccines among a population-based cohort of people with HIV in Ontario, Canada. DESIGN: Test-negative design. METHODS: We identified people with HIV aged ≥19 years who were tested for SARS-CoV-2 by RT-PCR between December 14, 2020 (first availability of COVID-19 vaccines) and November 21, 2021 (pre-Omicron circulation). Outcomes included any infection, symptomatic infection, and COVID-19-related hospitalization/death. We compared the odds of vaccination between test-positive cases and test-negative controls using multivariable logistic regression with adjustment for age, sex, region, calendar time, SARS-CoV-2 test histories, influenza vaccination, comorbidities, and neighborhood-level socio-economic status. VE was derived as (1 - adjusted odds ratio) × 100%. RESULTS: Among 21 023 adults living with HIV, there were 801 (8.3%) test-positive cases and 8,879 (91.7%) test-negative controls. 20.1% cases and 47.8% of controls received ≥1 COVID-19 vaccine dose; among two-dose recipients, 93.4% received ≥1 mRNA dose. Two-dose VE ≥7 days before specimen collection was 82% (95% confidence interval [CI] = 74-87%) against any infection, 94% (95% CI = 82-98%) against symptomatic infection, and 97% (95% CI = 85-100%) against hospitalization/death. Against any infection, VE declined from 86% (95% CI = 77-92%) within 7-59 days after the second dose to 66% (95% CI = -15-90%) after ≥180 days; we did not observe evidence of waning protection for other outcomes. CONCLUSION: Two doses of COVID-19 vaccine offered substantial protection against symptomatic illness and hospitalization/death in people with HIV prior to the emergence of the Omicron variant. Our findings do not support a broad conclusion that COVID-19 VE is lower among people with HIV in populations that, for the most part, are attending HIV care, taking antiretroviral medication, and are virally suppressed.


Subject(s)
COVID-19 , HIV Infections , Influenza Vaccines , Influenza, Human , Adult , Humans , COVID-19 Vaccines , Influenza, Human/prevention & control , COVID-19/epidemiology , COVID-19/prevention & control , BNT162 Vaccine , Vaccine Efficacy , SARS-CoV-2 , HIV Infections/complications , HIV Infections/drug therapy , Ontario/epidemiology
10.
BMJ Open ; 12(9): e062187, 2022 Sep 08.
Article in English | MEDLINE | ID: covidwho-2064156

ABSTRACT

PURPOSE: To investigate the robustness and longevity of SARS-CoV-2 immune responses conferred by natural infection and vaccination among priority populations such as immunocompromised individuals and people with post-acute sequelae of COVID-19 in a prospective cohort study (Stop the Spread Ottawa-SSO) in adults living in the Ottawa region. In this paper, we describe the study design, ongoing data collection and baseline characteristics of participants. PARTICIPANTS: Since October 2020, participants who tested positive for COVID-19 (convalescents) or at high risk of exposure to the virus (under surveillance) have provided monthly blood and saliva samples over a 10-month period. As of 2 November 2021, 1026 adults had completed the baseline survey and 976 had attended baseline bloodwork. 300 participants will continue to provide bimonthly blood samples for 24 additional months (ie, total follow-up of 34 months). FINDINGS TO DATE: The median age of the baseline sample was 44 (IQR 23, range: 18-79) and just over two-thirds (n=688; 67.1%) were female. 255 participants (24.9%) had a history of COVID-19 infection confirmed by PCR and/or serology. Over 600 participants (60.0%) work in high-risk occupations (eg, healthcare, teaching and transportation). 108 participants (10.5%) reported immunocompromising conditions or treatments at baseline (eg, cancer, HIV, other immune deficiency, and/or use of immunosuppressants). FUTURE PLANS: SSO continues to yield rich research potential, given the collection of pre-vaccine baseline data and samples from the majority of participants, recruitment of diverse subgroups of interest, and a high level of participant retention and compliance with monthly sampling. The 24-month study extension will maximise opportunities to track SARS-CoV-2 immunity and vaccine efficacy, detect and characterise emerging variants, and compare subgroup humoral and cellular response robustness and persistence.


Subject(s)
COVID-19 , Adult , Humans , Female , Male , SARS-CoV-2 , Antibody Formation , Prospective Studies , Antibodies , Vaccination , Immunity, Cellular , Antibodies, Viral
11.
Int J Environ Res Public Health ; 19(18)2022 Sep 15.
Article in English | MEDLINE | ID: covidwho-2055224

ABSTRACT

Proximity and duration of social contact while working or using public transportation may increase users' risk of SARS-CoV-2 exposure. This review aims to assess evidence of an association between use of public transportation or work in the transportation industry and prevalence of SARS-CoV-2 antibodies as well as to identify factors associated with seropositivity in transit users. A literature search of major databases was conducted from December 2019 to January 2022 using key worlds including "seroprevalence", "SARS-CoV-2", and "public transit". A narrative review of included studies was completed for the following categories: those working in the transportation industry, healthcare workers relying on public transit, and population-based studies. The association between work in the transit industry and seroprevalence varied based on location, demographic characteristics, and test sensitivities. No association was found in healthcare workers. Several population-based studies indicated higher seroprevalence in those using public transit. Overall seroprevalence estimates varied based on geographic location, population demographics, study methodologies, and calendar date of assessment. However, seropositivity was consistently higher in racial minorities and low-income communities.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Viral , COVID-19/epidemiology , Health Personnel , Humans , Seroepidemiologic Studies
12.
Frontiers in immunology ; 13, 2022.
Article in English | EuropePMC | ID: covidwho-2033745

ABSTRACT

Background Prognostic markers for COVID-19 disease outcome are currently lacking. Plasma gelsolin (pGSN) is an actin-binding protein and an innate immune marker involved in disease pathogenesis and viral infections. Here, we demonstrate the utility of pGSN as a prognostic marker for COVID-19 disease outcome;a test performance that is significantly improved when combined with cytokines and antibodies compared to other conventional markers such as CRP and ferritin. Methods Blood samples were longitudinally collected from hospitalized COVID-19 patients as well as COVID-19 negative controls and the levels of pGSN in μg/mL, cytokines and anti- SARS-CoV-2 spike protein antibodies assayed. Mean ± SEM values were correlated with clinical parameters to develop a prognostic platform. Results pGSN levels were significantly reduced in COVID-19 patients compared to healthy individuals. Additionally, pGSN levels combined with plasma IL-6, IP-10 and M-CSF significantly distinguished COVID-19 patients from healthy individuals. While pGSN and anti-spike IgG titers together strongly predict COVID-19 severity and death, the combination of pGSN and IL-6 was a significant predictor of milder disease and favorable outcomes. Conclusion Taken together, these findings suggest that multi-parameter analysis of pGSN, cytokines and antibodies could predict COVID-19 hospitalization outcomes with greater certainty compared with conventional clinical laboratory markers such as CRP and ferritin. This research will inform and improve clinical management and health system interventions in response to SARS-CoV-2 infection.

13.
BMJ open ; 12(9), 2022.
Article in English | EuropePMC | ID: covidwho-2011138

ABSTRACT

Purpose To investigate the robustness and longevity of SARS-CoV-2 immune responses conferred by natural infection and vaccination among priority populations such as immunocompromised individuals and people with post-acute sequelae of COVID-19 in a prospective cohort study (Stop the Spread Ottawa—SSO) in adults living in the Ottawa region. In this paper, we describe the study design, ongoing data collection and baseline characteristics of participants. Participants Since October 2020, participants who tested positive for COVID-19 (convalescents) or at high risk of exposure to the virus (under surveillance) have provided monthly blood and saliva samples over a 10-month period. As of 2 November 2021, 1026 adults had completed the baseline survey and 976 had attended baseline bloodwork. 300 participants will continue to provide bimonthly blood samples for 24 additional months (ie, total follow-up of 34 months). Findings to date The median age of the baseline sample was 44 (IQR 23, range: 18–79) and just over two-thirds (n=688;67.1%) were female. 255 participants (24.9%) had a history of COVID-19 infection confirmed by PCR and/or serology. Over 600 participants (60.0%) work in high-risk occupations (eg, healthcare, teaching and transportation). 108 participants (10.5%) reported immunocompromising conditions or treatments at baseline (eg, cancer, HIV, other immune deficiency, and/or use of immunosuppressants). Future plans SSO continues to yield rich research potential, given the collection of pre-vaccine baseline data and samples from the majority of participants, recruitment of diverse subgroups of interest, and a high level of participant retention and compliance with monthly sampling. The 24-month study extension will maximise opportunities to track SARS-CoV-2 immunity and vaccine efficacy, detect and characterise emerging variants, and compare subgroup humoral and cellular response robustness and persistence.

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