Real-world COVID-19 vaccine effectiveness against the Omicron BA.2 variant in a SARS-CoV-2 infection-naive population

Nature Medicine, Journal Year: 2023, Volume and Issue: 29(2), P. 348 - 357

Published: Jan. 18, 2023

The SARS-CoV-2 Omicron variant has demonstrated enhanced transmissibility and escape of vaccine-derived immunity. Although first-generation vaccines remain effective against severe disease death, robust evidence on vaccine effectiveness (VE) all infections, irrespective symptoms, remains sparse. We used a community-wide serosurvey with 5,310 subjects to estimate how vaccination histories modulated risk infection in infection-naive Hong Kong during large wave BA.2 epidemic January-July 2022. estimated that infected 45% (41-48%) the local population. Three four doses BNT162b2 or CoronaVac were 7 days after (VE 48% (95% credible interval 34-64%) 69% (46-98%) for three BNT162b2, respectively; VE 30% (1-66%) 56% (6-97%) CoronaVac, respectively). At 100 immunization, waned 26% (7-41%) 35% (10-71%) 6% (0-29%) 11% (0-54%) CoronaVac. rapid waning conferred by an increasingly complex viral evolutionary landscape highlight necessity rapidly deploying updated followed vigilant monitoring VE.

Language: Английский

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Learning to Fake It: Limited Responses and Fabricated References Provided by ChatGPT for Medical Questions

Mayo Clinic Proceedings Digital Health, Journal Year: 2023, Volume and Issue: 1(3), P. 226 - 234

Published: June 12, 2023

To evaluate the quality of answers and references provided by ChatGPT for medical questions. Three researchers asked 20 questions prompted it to provide corresponding references. The responses were evaluated content experts using a verbal numeric scale going from 0% 100%. These authors articles where derived. We planned 3 per response their pertinence, but this was amended on basis preliminary results showing that most fabricated. This experimental observational study conducted in February 2023. varying between 53 244 words long reported 2 7 answer. Seventeen invited raters feedback. limited responses, with median score 60% (first third quartiles: 50% 85%, respectively). In addition, they identified major (n=5) minor (n=7) factual errors among 17 responses. Of 59 evaluated, 41 (69%) fabricated, although appeared real. Most fabricated citations used names previous relevant publications, title seemed pertinent credible journal format. When multiple questions, scientific publication. More importantly, deceptively real Users should pay particular attention before integration into manuscripts.

Language: Английский

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Respiratory syncytial virus epidemiology and clinical severity before and during the COVID-19 pandemic in British Columbia, Canada: a retrospective observational study

The Lancet Regional Health - Americas, Journal Year: 2023, Volume and Issue: 25, P. 100582 - 100582

Published: Aug. 30, 2023

The COVID-19 pandemic has perturbed the seasonality of respiratory syncytial virus (RSV) infections. However, we lack data on how this impacted severity paediatric RSV cases. objective study was to describe clinical cases before, during and after measures in British Columbia (BC), Canada. Retrospective from September 1st, 2017 May 15th, 2023, with a review outcomes children below 18 years old at BC's hospital. Temporal changes hospitalisations were quantified using interrupted time series. BC experienced only 11 (from 95,266 tests) between 2020 August 2021. This followed by resurgence 9,529 (219,566 tests [4.3% positive tests]) 2021–22 8,215 (124,449 [6.6% 2022–23, increased compared 1,750 (48,664 [3.6% per corresponding yearly period 2017–20. From median age Children's Hospital 8.7 [IQR: 2.0–26.0] 19.6 [3.9–43.7] months period. More hospitalised 2022–23 (n = 360), 2017–20 168 period) 172). detected no increase or ICU admissions born prematurely chronic cardiorespiratory conditions. detection symptomatic older RSV-related suggest gradual pool immunologically vulnerable due prolonged viral exposure. Government Canada via its Immunity Task Force.

Language: Английский

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The evolution of SARS-CoV-2 seroprevalence in Canada: a time-series study, 2020–2023

Canadian Medical Association Journal, Journal Year: 2023, Volume and Issue: 195(31), P. E1030 - E1037

Published: Aug. 13, 2023

Background:

During the first year of COVID-19 pandemic, proportion reported cases among Canadians was under 6%. Although high vaccine coverage achieved in Canada by fall 2021, Omicron variant caused unprecedented numbers infections, overwhelming testing capacity and making it difficult to quantify trajectory population immunity.

Methods:

Using a time-series approach data from more than 900 000 samples collected 7 research studies collaborating with Immunity Task Force (CITF), we estimated trends SARS-CoV-2 seroprevalence owing infection vaccination for Canadian over 3 intervals: prevaccination (March November 2020), roll-out (December 2020 2021), arrival 2021 March 2023). We also geographical region age.

Results:

By 9.0% (95% credible interval [CrI] 7.3%–11%) people had humoral immunity an infection. Seroprevalence increased rapidly after — Mar. 15, 2023, 76% CrI 74%–79%) detectable antibodies infections. The rapid rise infection-induced occurred across most pronounced younger age groups Western provinces: Manitoba, Saskatchewan, Alberta British Columbia.

Interpretation:

Data up 2023 indicate that acquired against through natural vaccination. However, given variations seropositivity geography, potential waning antibody levels, new variants may escape immunity, public health policy clinical decisions should be tailored local patterns

Language: Английский

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Learning to fake it: limited responses and fabricated references provided by ChatGPT for medical questions

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: March 24, 2023

Abstract Background ChatGPT have gained public notoriety and recently supported manuscript preparation. Our objective was to evaluate the quality of answers references provided by for medical questions. Methods Three researchers asked a total 20 questions prompted it provide corresponding references. The responses were evaluated content experts using verbal numeric scale going from 0 100%. These author articles where derived. We planned three per response their pertinence, but this amended based on preliminary results showing that most fabricated. Results varying between 53 244 words long reported two seven answer. Seventeen invited raters feedback. limited with median score 60% (1 st 3 rd quartile: 50% 85%). Additionally, they identified major (n=5) minor (n=7) factual errors among 17 responses. Of 59 evaluated, 41 (69%) fabricated, though appeared real. Most fabricated citations used names authors previous relevant publications, title seemed pertinent credible journal format. Interpretation When multiple questions, scientific publication. More importantly, deceptively real Users should pay particular attention before integration into manuscripts.

Language: Английский

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Changes in emergency department use in British Columbia, Canada, during the first 3 years of the COVID-19 pandemic

Canadian Medical Association Journal, Journal Year: 2023, Volume and Issue: 195(34), P. E1141 - E1150

Published: Sept. 4, 2023

Previous studies have shown reductions in the volume of emergency department visits early COVID-19 pandemic, but few evaluated pandemic's impact over time or stratified analyses by reason for visits. We aimed to quantify such changes British Columbia, Canada, cumulatively and during prominent nadirs, visit, age acuity.We included data from National Ambulatory Care Reporting System 30 departments across BC January 2016 December 2022. fitted generalized additive models, accounting seasonal annual trends, monthly number estimate throughout compared with expected absence pandemic. determined absolute relative differences at various times study period, since start pandemic until overall returned levels.Over first 16 months was reduced about 322 300 visits, 15% (95% confidence interval 12%-18%), volume. A sharp drop pediatric accounted nearly one-third reduction. The timing return baseline differed subgroup. largest most sustained decreases were respiratory-related among children, oldest adults non-urgent Later we observed increased volumes highest-urgency children related ear, nose throat.We extended evidence that associated mitigation strategies on Canada substantial. Both our findings methods are relevant public health surveillance capacity planning nonpandemic times.

Language: Английский

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Effectiveness of previous infection-induced and vaccine-induced protection against hospitalisation due to omicron BA subvariants in older adults: a test-negative, case-control study in Quebec, Canada

The Lancet Healthy Longevity, Journal Year: 2023, Volume and Issue: 4(8), P. e409 - e420

Published: July 14, 2023

Older adults (aged ≥60 years) were prioritised for COVID-19 booster vaccination due to severe outcome risk, but the risk this group is also affected by previous SARS-CoV-2 infection and vaccination. We estimated vaccine effectiveness against omicron-associated hospitalisation in older previously documented infection, time since last immunological event, age group.This was a population-based test-negative case-control study done Quebec, Canada, during BA.1 dominant (December, 2021, March, 2022), BA.2 (April June, BA.4/5 (July November, 2022) periods using provincial laboratory, immunisation, hospitalisation, chronic disease surveillance databases. included with symptoms associated who tested acute-care hospitals. Cases defined as patients hospitalised within 14 days after testing positive; controls negative. Analyses spanned 3-14 months dose or infection. Logistic regression models compared mRNA versus unvaccinated infection-naive participants.Between Dec 26, Nov 5, 2022, we 174 819 specimens (82 870 [47·4%] from men 91 949 [52·6%] women; 8455 cases 166 364 controls), taken 2951 48 724 period; 1897 41 702 3607 75 938 period. In participants naive, improved number, consistent shorter median dose, decreased more recent omicron subvariants. Four-dose 96% (95% CI 93-98) period, 84% (81-87) 68% (63-72) Regardless of number (two five doses) timing hybrid protection than 90%, persisted at least 6-8 months, did not decline age.Older both two doses appear be well protected prolonged period subvariants, including BA.4/5. Ensuring that are naive remain up date might reduce hospitalisations most efficiently.Ministère de la Santé et des Services Sociaux du Québec.For French translation abstract see Supplementary Materials section.

Language: Английский

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Molecular epidemiology and population immunity of SARS-CoV-2 in Guangdong (2022–2023) following a pivotal shift in the pandemic

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Aug. 15, 2024

The SARS-CoV-2 Omicron variant sparked the largest wave of infections worldwide. Mainland China eased its strict COVID-19 measures in late 2022 and experienced two nationwide waves 2023. Here, we investigated lineage distribution virus evolution Guangdong, China, 2022-2023 by comparing 5813 local viral genomes with datasets from other regions Additionally, conducted three large-scale serological surveys involving 1696 participants to measure their immune response BA.5 XBB.1.9 before after corresponding waves. Our findings revealed variants, mainly BA.5.2.48 lineage, causing over 90% individuals across different age groups within a month. This rapid spread led establishment widespread immunity, limiting virus's ability further adaptive mutation dissemination. While similar responses were observed all initial wave, children aged 3 11 developed stronger cross strain, possibly explaining lower infection rates following XBB.1 wave. Reinfection triggered more potent neutralizing among older adults. These highlight impact age-specific on potential future Release zero-COVID policy large Omicron-driven authors analyze serology data describe changes antibody responses.

Language: Английский

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The role of vaccine status homophily in the COVID-19 pandemic: a cross-sectional survey with modelling

BMC Public Health, Journal Year: 2024, Volume and Issue: 24(1)

Published: Feb. 14, 2024

Abstract Background Vaccine homophily describes non-heterogeneous vaccine uptake within contact networks. This study was performed to determine observable patterns of homophily, as well the impact on disease transmission and between vaccination groups under conditions high low efficacy. Methods Residents British Columbia, Canada, aged ≥ 16 years, were recruited via online advertisements February March 2022, provided information about status, perceived status household non-household contacts, compliance with COVID-19 prevention guidelines, history COVID-19. A deterministic mathematical model used assess dynamics Results observed among those 0, 2, or 3 doses vaccine. Greater who had more ( p < 0.0001). Those fewer larger networks 0.0001), likely report prior reported lower guidelines Mathematical modelling showed that plays a considerable role in epidemic growth Furthermore, contributes force infection unvaccinated individuals efficacy, an elevated from suboptimally vaccinated Interpretation The uneven vaccines nature network population play important roles shaping dynamics.

Language: Английский

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Comparison of influenza and COVID-19 hospitalisations in British Columbia, Canada: a population-based study

BMJ Open Respiratory Research, Journal Year: 2023, Volume and Issue: 10(1), P. e001567 - e001567

Published: Feb. 1, 2023

Introduction We compared the population rate of COVID-19 and influenza hospitalisations by age, vaccine status pandemic phase, which was lacking in other studies. Method conducted a population-based study using hospital data from province British Columbia (population 5.3 million) Canada with universal healthcare coverage. created two cohorts based on date admission: annual cohort (March 2020 to February 2021) peak (Omicron era; first 10 weeks 2022). For comparison, we three historical periods years capture varying severity circulating strains: 2009/2010, 2015/2016 2016/2017. estimated hospitalisation rates per 100 000 population. Results age group were ‘J’ shaped. The admissions (mostly unvaccinated; public health restrictions place) significantly higher than among individuals aged 30–69 years, comparable severe year (2016/2017) 70+. In vaccinated; few place), 2016/2017 all groups, although unvaccinated still 18+. Among people 5–17 lower than/comparable both cohorts. 0–4 old, during Omicron, 2009/2010 pandemic. Conclusions During Omicron wave, for adults but vaccinated adults. children, context high infection levels, H1N1 (higher 0–4) non-pandemic regardless status.

Language: Английский

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