ORCID Profile
0000-0003-0835-9504
Current Organisations
University of British Columbia
,
BC Children's Hospital
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Publisher: Springer Science and Business Media LLC
Date: 07-01-2020
DOI: 10.1186/S12916-019-1470-Y
Abstract: Endometriosis is a gynaecological condition characterised by immune cell infiltration and distinct inflammatory signatures found in the peritoneal cavity. In this study, we aim to characterise the immune microenvironment in s les isolated from the peritoneal cavity in patients with endometriosis. We applied mass cytometry (CyTOF), a recently developed multiparameter single-cell technique, in order to characterise and quantify the immune cells found in peritoneal fluid and peripheral blood from endometriosis and control patients. Our results demonstrate the presence of more than 40 different distinct immune cell types within the peritoneal cavity. This suggests that there is a complex and highly heterogeneous inflammatory microenvironment underpinning the pathology of endometriosis. Stratification by clinical disease stages reveals a dynamic spectrum of cell signatures suggesting that adaptations in the inflammatory system occur due to the severity of the disease. Notably, among the inflammatory microenvironment in peritoneal fluid (PF), the presence of CD69 + T cell subsets is increased in endometriosis when compared to control patient s les. On these CD69 + cells, the expression of markers associated with T cell function are reduced in PF s les compared to blood. Comparisons between CD69 + and CD69 − populations reveal distinct phenotypes across peritoneal T cell lineages. Taken together, our results suggest that both the innate and the adaptive immune system play roles in endometriosis. This study provides a systematic characterisation of the specific immune environment in the peritoneal cavity and identifies cell immune signatures associated with endometriosis. Overall, our results provide novel insights into the specific cell phenotypes governing inflammation in patients with endometriosis. This prospective study offers a useful resource for understanding disease pathology and opportunities for identifying therapeutic targets.
Publisher: BMJ
Date: 04-2022
DOI: 10.1136/BMJOPEN-2021-057846
Abstract: Few studies reported COVID-19 cases in schools during the 2020/21 academic year in a setting of uninterrupted in-person schooling. The main objective was to determine the SARS-CoV-2 seroprevalence among school staff in Vancouver public schools. Cumulative incident COVID-19 cases among all students and school staff based on public health data, with an embedded cross-sectional serosurvey among a school staff s le that was compared to period, age, sex and geographical location-weighted data from blood donors. Vancouver School District (British Columbia, Canada) from kindergarten to grade 12. Active school staff enrolled from 3 February to 23 April 2021 with serology testing from 10 February to 15 May 2021. SARS-CoV-2 seroprevalence among school staff, based on spike (S)-based (unvaccinated staff) or N-based serology testing (vaccinated staff). Public health data showed the cumulative incidence of COVID-19 among students attending in-person was 9.8 per 1000 students (n=47 280), and 13 per 1000 among school staff (n=7071). In a representative s le of 1689 school staff, 78.2% had classroom responsibilities, and spent a median of 17.6 hours in class per week (IQR: 5.0–25 hours). Although 21.5% (363/1686) of surveyed staff self-reported close contact with a COVID-19 case outside of their household (16.5% contacts were school-based), 5 cases likely acquired the infection at school based on viral testing. Sensitivity/Specificity-adjusted seroprevalence in 1556/1689 staff (92.1%) was 2.3% (95% CI: 1.6% to 3.2%), comparable to a sex, age, date and residency area-weighted seroprevalence of 2.6% (95% CI: 2.2% to 3.1%) among 5417 blood donors. Seroprevalence among staff was comparable to a reference group of blood donors from the same community. These data show that in-person schooling could be safely maintained during the 2020/21 school year with mitigation measures, in a large school district in Vancouver, Canada.
Publisher: Cold Spring Harbor Laboratory
Date: 04-03-2022
DOI: 10.1101/2022.03.01.482592
Abstract: Emerging evidence indicates that longer SARS-CoV-2 vaccine dosing intervals results in an enhanced immune response. However, the optimal vaccine dosing interval for achieving maximum immunogenicity is unclear. This study included s les from adult paramedics in Canada who received two doses of either BNT162b2 or mRNA-1273 vaccines and provided blood s les 6 months (170 to 190 days) after the first vaccine dose. The main exposure variable was vaccine dosing interval (days), categorized as “ short ” (first quartile), “ moderate ” (second quartile), “ long ” (third quartile), and “ longest” interval (fourth quartile). The primary outcome was total spike antibody concentrations, measured using the Elecsys SARS-CoV-2 total antibody assay. Secondary outcomes included: spike and RBD IgG antibody concentrations, and inhibition of angiotensin-converting enzyme 2 (ACE-2) binding to wild-type spike protein and several different Delta variant spike proteins. We fit a multiple log-linear regression model to investigate the association between vaccine dosing intervals and the antibody concentrations. A total of 564 adult paramedics (mean age 40 years, SD=10) were included. Compared to “short interval” (≤30 days), higher dosing interval quartiles ( moderate : 31-38 days long : 39-73 days and longest : ≥74 days) were all associated with increased Elescys spike total antibody concentration. Compared to the short interval, “ long ” and “ longest ” interval quartiles were associated with higher spike and RBD IgG antibody concentrations. Similarly, increasing dosing intervals increased inhibition of ACE-2 binding to viral spike protein, regardless of the vaccine type. Increased mRNA vaccine dosing intervals longer than 30 days result in higher levels of circulating antibodies and viral neutralization when assessed at 6 months.
Publisher: American Society for Microbiology
Date: 23-02-2022
DOI: 10.1128/SPECTRUM.01454-21
Abstract: Among a cohort of adult paramedics in Canada, we investigated the performance of nucleocapsid (N) antibody detection (measured with a V-PLEX assay) to identify previous COVID-19 infections and compared differences among vaccinated and unvaccinated. Our data indicate that vaccinated and unvaccinated groups require different thresholds to achieve optimal test performance, especially for detecting COVID-19 within the preceding 9 months.
Publisher: American Society for Microbiology
Date: 27-04-2022
DOI: 10.1128/SPECTRUM.02702-21
Abstract: The BNT162b2 and mRNA-1273 mRNA SARS-CoV-2 vaccines have demonstrated high efficacy for preventing short-term COVID-19. However, comparative long-term effectiveness is unclear, especially pertaining to the Delta variant.
Publisher: Elsevier BV
Date: 07-2022
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2019
Publisher: Oxford University Press (OUP)
Date: 17-05-2022
DOI: 10.1093/OFID/OFAC229
Abstract: The prevalence and clinical relevance of human herpesvirus-6 (HHV-6) detection in cerebrospinal fluid (CSF) using multiplex polymerase chain reaction (PCR) testing in patients with suspected meningoencephalitis in high human immunodeficiency virus-prevalence African settings are not known. We describe the clinical and laboratory characteristics of 13 patients with HHV-6 CSF PCR positivity in Botswana.
Publisher: Oxford University Press (OUP)
Date: 26-07-2022
DOI: 10.1093/OFID/OFAC349
Abstract: Nucleocapsid serological assay sensitivity to identify severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections among vaccinees and for Omicron cases is unclear. In this prospective study, the Elecsys nucleocapsid assay was 89% sensitive in identifying SARS-CoV-2 infections 14–607 days pre–blood collection. Sensitivity was similar when comparing by vaccination status, and in Omicron (vs pre-Omicron) cases.
Publisher: American Society for Microbiology
Date: 31-08-2022
DOI: 10.1128/SPECTRUM.00622-22
Abstract: There is concern that schools may be a setting where asymptomatic infections might result in significant “silent” transmission of SARS-CoV-2, particularly after the emergence of more transmissible variants of concern. After the programmatic implementation of a strategy of asymptomatic testing of close COVID-19 contacts as part of contact tracing in the school setting, the majority of the secondary cases were still found to have occurred in home or social contacts.
Publisher: Oxford University Press (OUP)
Date: 28-04-2022
DOI: 10.1093/PCH/PXAB110
Abstract: Multisystem Inflammatory Syndrome in Children (MIS-C) is a post-infectious complication of SARS-CoV-2 infection with overlapping features of Kawasaki disease and toxic shock syndrome. In May 2020, a provincial multidisciplinary working group was established in anticipation of emerging cases following the first wave of SARS-CoV-2 infections. Our centre established a multidisciplinary working group for MIS-C cases in British Columbia. The group developed guidelines using the World Health Organization MIS-C case definition. Guidelines were updated using quality improvement methods as new reports and our local experience evolved. We included all children who were evaluated in person or had s les sent to our centre for MIS-C evaluation from May 2020 to April 2021. We prospectively collected patient demographics, clinical and laboratory characteristics, and treatment. Fifty-two children were included. Eleven were diagnosed as confirmed MIS-C. Ten of the 11 MIS-C cases presented with shock. Gastrointestinal and mucocutaneous involvement were also prominent. Common laboratory features included elevated C-reactive protein, D-dimer, troponin, and brain natriuretic peptide. Four out of 11 (36%) had myocardial dysfunction and 3/11 (27%) had coronary artery abnormalities. All 11 patients had evidence of SARS-CoV-2 infection. Ten out of 11 (91%) received intravenous (IV) immunoglobulin and IV corticosteroids. Our provincial cohort of MIS-C patients were more likely to present with shock and cardiac dysfunction, require ICU admission, and be treated with corticosteroids compared to ruled out cases. Our working group’s evolving process ensured children with features of MIS-C were rapidly identified, had standardized evaluation, and received appropriate treatment in our province.
Publisher: Cold Spring Harbor Laboratory
Date: 18-06-2021
DOI: 10.1101/2021.06.16.21258861
Abstract: Contact-tracing studies suggest minimal secondary transmission in schools. However, there are limited school data accounting for asymptomatic cases, particularly late in the 2020/21 school year, and in the context of uninterrupted in-person schooling and widespread community transmission. To determine the SARS-CoV-2 seroprevalence in a s le of school staff, compared to the community, and to COVID-19 rates among all students and staff within the same school population. Incident COVID-19 cases among students and school staff using public health data, with an embedded cross-sectional serosurvey among school staff s led from February 10 to May 15, 2021, comparing to age, sex and geographic location-matched blood donors s led in January 2021. Vancouver School District (British Columbia, Canada) from kindergarten to grade 12. Active s chool staff enrolled from February 3 to April 23, 2021. SARS-CoV-2 antibodies in a s le of school staff using spike (S)-based testing (unvaccinated staff) or N-based serology testing (vaccinated staff). The incidence of COVID-19 cases among students attending in-person was 9.8 per 1,000 students during the 2020/21 school year (N = 47,280 students), and among staff was 13 per 1,000 since the beginning of the pandemic (N = 7,071 active school staff). In total, 1,689 school staff (64% elementary, 28% secondary, 8.3% school board staff or multiple grades) completed the questionnaire, 78.2% had classroom responsibilities, and spent a median of 17.6 hours in class per week [IQR: 5.0 – 25 hours]. Although 21.5% (363/1,686) reported close contact with a COVID-19 case, only 1.4% (24/1688) of the school staff reported having had a positive viral nucleic acid test. Of this group, five believed they acquired the infection at school. The adjusted seroprevalence in staff who gave blood (1,556/1,689, 92.1%) was 2.3% [95%CI: 1.6 – 3.2%] compared to 2.3% [95%CI: 1.7 – 3.0%] in blood donors. Despite high reported COVID-19 cases among students and staff, and frequent within-school exposures, we found no detectable increase in seroprevalence among school staff above the community seroprevalence. These findings corroborate claims that, with appropriate mitigation strategies, in-person schooling is not associated with significantly increased risk for school staff. What was the prevalence of COVID-19 infections in school staff who maintained in-person schooling during the 2020/21 school year in Vancouver, British Columbia, and how does it compare to the risk of COVID-19 infection in the community. As of March 4, 2021, the incidence of COVID-19 cases among school staff was 13 per 1,000 (N = 7,071 school staff) since the beginning of the pandemic. In a cross-sectional seroprevalence analysis from February 10 to May 15, 2021, the adjusted seroprevalence among a s le of school staff (N = 1,556) was 2.3% [95%CI: 1.6 – 3.2%], compared to 2.3% [95%CI: 1.7 – 3.0%] in 1:2 age, sex and geographical location (by postal code)-matched reference group of blood donors. We found no detectable increase in seroprevalence among school staff above the community seroprevalence. These findings corroborate claims that, with appropriate mitigation strategies in place, in-person schooling is not associated with significantly higher risk for school staff.
Publisher: Microbiology Society
Date: 17-10-2023
Publisher: Elsevier BV
Date: 06-2023
Publisher: Elsevier BV
Date: 02-2022
No related grants have been discovered for David Goldfarb.