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1.
Sex Transm Infect ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702191

RESUMO

OBJECTIVES: Antibiotic resistance in gonorrhoea is of significant public health concern with the emergence of resistance to last-line therapies such as ceftriaxone. Despite around half of Neisseria gonorrhoeae isolates tested in the UK being susceptible to ciprofloxacin, very little ciprofloxacin is used in clinical practice. Testing for the S91F mutation associated with ciprofloxacin resistance is now available in CE-marked assays and may reduce the requirement for ceftriaxone, but many patients are treated empirically, or as sexual contacts, which may limit any benefit. We describe the real-world impact of such testing on antimicrobial use and clinical outcomes in people found to have gonorrhoea in a large urban UK sexual health clinic. METHODS: Molecular ciprofloxacin resistance testing (ResistancePlus GC assay (SpeeDx)) was undertaken as an additional test after initial diagnosis (m2000 Realtime CT/NG assay (Abbott Molecular)) in those not already known to have had antimicrobial treatment. Data from a 6-month period (from March to September 2022) were analysed to determine treatment choice and treatment outcome. RESULTS: A total of 998 clinical samples tested positive for N. gonorrhoeae in 682 episodes of infection. Of the 560 (56%) samples eligible for resistance testing, 269 (48.0%) were reported as wild-type, 180 (32.1%) were predicted to be resistant, 63 (11.3%) had an indeterminate resistance profile, and in 48 (8.6%) samples, N. gonorrhoeae was not detected. Ciprofloxacin was prescribed in 172 (75%) of 228 episodes in which the wild-type strain was detected. Four (2%) of those treated with ciprofloxacin had a positive test-of-cure sample by NAAT, with no reinfection risk. All four had ciprofloxacin-susceptible infection by phenotypic antimicrobial susceptibility testing. CONCLUSIONS: In routine practice in a large UK clinic, molecular ciprofloxacin resistance testing led to a significant shift in antibiotic use, reducing use of ceftriaxone. Testing can be targeted to reduce unnecessary additional testing. Longer term impact on antimicrobial resistance requires ongoing surveillance.

2.
Biotechniques ; 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38706171

RESUMO

In 2019, the European Union banned Triton X-100, a detergent widely used in laboratory diagnostics, including the Viral PCR Sample Solution (VPSS), and urged manufacturers to find environmentally sustainable alternatives. Tergitol 15-S-9 (VPSS2) has been proposed as an alternative surfactant. This multicenter study evaluated the effectiveness of VPSS2, a Tergitol-based viral solution, as a replacement for VPSS. Our results show the equivalent performance of VPSS2 to VPSS for nucleic acid extraction and viral stability over time at different temperatures. The new VPSS formulation was also tested against external quality assurance panels and clinical samples. The results of this work support adopting this modified viral PCR sample solution to replace Triton X-100-containing viral transport solutions.

3.
Influenza Other Respir Viruses ; 18(5): e13295, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38744684

RESUMO

BACKGROUND: The 2022/23 influenza season in the United Kingdom saw the return of influenza to prepandemic levels following two seasons with low influenza activity. The early season was dominated by A(H3N2), with cocirculation of A(H1N1), reaching a peak late December 2022, while influenza B circulated at low levels during the latter part of the season. From September to March 2022/23, influenza vaccines were offered, free of charge, to all aged 2-13 (and 14-15 in Scotland and Wales), adults up to 49 years of age with clinical risk conditions and adults aged 50 and above across the mainland United Kingdom. METHODS: End-of-season adjusted vaccine effectiveness (VE) estimates against sentinel primary-care attendance for influenza-like illness, where influenza infection was laboratory confirmed, were calculated using the test negative design, adjusting for potential confounders. METHODS: Results In the mainland United Kingdom, end-of-season VE against all laboratory-confirmed influenza for all those > 65 years of age, most of whom received adjuvanted quadrivalent vaccines, was 30% (95% CI: -6% to 54%). VE for those aged 18-64, who largely received cell-based vaccines, was 47% (95% CI: 37%-56%). Overall VE for 2-17 year olds, predominantly receiving live attenuated vaccines, was 66% (95% CI: 53%-76%). CONCLUSION: The paper provides evidence of moderate influenza VE in 2022/23.


Assuntos
Vírus da Influenza A Subtipo H3N2 , Vírus da Influenza B , Vacinas contra Influenza , Influenza Humana , Atenção Primária à Saúde , Eficácia de Vacinas , Humanos , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Influenza Humana/epidemiologia , Pessoa de Meia-Idade , Adolescente , Adulto , Atenção Primária à Saúde/estatística & dados numéricos , Reino Unido/epidemiologia , Idoso , Adulto Jovem , Criança , Feminino , Masculino , Pré-Escolar , Vírus da Influenza A Subtipo H3N2/imunologia , Vírus da Influenza B/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Estações do Ano , Vacinação/estatística & dados numéricos
4.
AIDS Behav ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649554

RESUMO

Glasgow, Scotland's largest city, has been experiencing an HIV outbreak among people who inject drugs (PWID) since 2015. A key focus of the public health response has been to increase HIV testing among those at risk of infection. Our aim was to assess the impact of COVID-19 on HIV testing among PWID in Glasgow. HIV test uptake in the last 12 months was quantified among: (1) PWID recruited in six Needle Exchange Surveillance Initiative (NESI) surveys (n = 6110); linked laboratory data for (2) people prescribed opioid agonist therapy (OAT) (n = 14,527) and (3) people hospitalised for an injecting-related hospital admission (IRHA) (n = 12,621) across four time periods: pre-outbreak (2010-2014); early-outbreak (2015-2016); ongoing-outbreak (2017-2019); and COVID-19 (2020-June 21). From the pre to ongoing period, HIV testing increased: the highest among people recruited in NESI (from 28% to 56%) and on OAT (from 17% to 54%) while the lowest was among people with an IRHA (from 15% to 42%). From the ongoing to the COVID-19 period, HIV testing decreased markedly among people prescribed OAT, from 54% to 37% (aOR 0.50, 95% CI 0.48-0.53), but increased marginally among people with an IRHA from 42% to 47% (aOR 1.19, 95% CI 1.08-1.31). In conclusion, progress in increasing testing in response to the HIV outbreak has been eroded by COVID-19. Adoption of a linked data approach could be warranted in other settings to inform efforts to eliminate HIV transmission.

5.
J Clin Virol ; 167: 105574, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37639778

RESUMO

BACKGROUND: The challenges of rapid upscaling of testing capacity were a major lesson from the COVID-19 pandemic response. The need for process adjustments in high-throughput testing laboratories made sample pooling a challenging option to implement. OBJECTIVE: This study aimed to evaluate whether pooling samples at source (swab pooling) was as effective as qRT-PCR testing of individuals in identifying cases of SARS-CoV-2 in real-world community testing conditions using the same high-throughput pipeline. METHODS: Two cohorts of 10 (Pool10: 1,030 participants and 103 pools) and 6 (Pool6: 1,284 participants and 214 pools) samples per pool were tested for concordance, sensitivity, specificity, and Ct value differences with individual testing as reference. RESULTS: Swab pooling allowed unmodified application of an existing high-throughput SARS-Cov-2 testing pipeline with only marginal loss of accuracy. For Pool10, concordance was 98.1% (95% Confidence interval: 93.3-99.8%), sensitivity was 95.7% (85.5-99.5%), and specificity was 100.0% (93.6-100.0%). For Pool6, concordance was 97.2% (94.0-99.0%), sensitivity was 97.5% (93.7-99.3%), and specificity was 96.4% (87.7-99.6%). Differences of outcomes measure between pool size were not significant. Most positive individual samples, which were not detected in pools, had very low viral concentration. If only individual samples with a viral concentration > 400 copies/ml (i.e. Ct value < 30) were considered positive, the overall sensitivity of pooling increased to 99.5%. CONCLUSION: The study demonstrated high sensitivity and specificity by swab pooling and the immediate capability of high-throughput laboratories to implement this method making it an option in planning of rapid upscaling of laboratory capacity for future pandemics.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , Teste para COVID-19 , Pandemias , Laboratórios
6.
J Infect ; 87(2): 128-135, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37270070

RESUMO

OBJECTIVES: To determine how the intrinsic severity of successively dominant SARS-CoV-2 variants changed over the course of the pandemic. METHODS: A retrospective cohort analysis in the NHS Greater Glasgow and Clyde (NHS GGC) Health Board. All sequenced non-nosocomial adult COVID-19 cases in NHS GGC with relevant SARS-CoV-2 lineages (B.1.177/Alpha, Alpha/Delta, AY.4.2 Delta/non-AY.4.2 Delta, non-AY.4.2 Delta/Omicron, and BA.1 Omicron/BA.2 Omicron) during analysis periods were included. Outcome measures were hospital admission, ICU admission, or death within 28 days of positive COVID-19 test. We report the cumulative odds ratio; the ratio of the odds that an individual experiences a severity event of a given level vs all lower severity levels for the resident and the replacement variant after adjustment. RESULTS: After adjustment for covariates, the cumulative odds ratio was 1.51 (95% CI: 1.08-2.11) for Alpha versus B.1.177, 2.09 (95% CI: 1.42-3.08) for Delta versus Alpha, 0.99 (95% CI: 0.76-1.27) for AY.4.2 Delta versus non-AY.4.2 Delta, 0.49 (95% CI: 0.22-1.06) for Omicron versus non-AY.4.2 Delta, and 0.86 (95% CI: 0.68-1.09) for BA.2 Omicron versus BA.1 Omicron. CONCLUSIONS: The direction of change in intrinsic severity between successively emerging SARS-CoV-2 variants was inconsistent, reminding us that the intrinsic severity of future SARS-CoV-2 variants remains uncertain.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Humanos , SARS-CoV-2/genética , Estudos Retrospectivos , Hospitalização
7.
Viruses ; 15(6)2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37376548

RESUMO

Nanopore sequencing is becoming increasingly commonplace in clinical settings, particularly for diagnostic assessments and outbreak investigations, due to its portability, low cost, and ability to operate in near real-time. Although high sequencing error rates initially hampered the wider implementation of this technology, improvements have been made continually with each iteration of the sequencing hardware and base-calling software. Here, we assess the feasibility of using nanopore sequencing to determine the complete genomes of human cytomegalovirus (HCMV) in high-viral-load clinical samples without viral DNA enrichment, PCR amplification, or prior knowledge of the sequences. We utilised a hybrid bioinformatic approach that involved assembling the reads de novo, improving the consensus sequence by aligning reads to the best-matching genome from a collated set of published sequences, and polishing the improved consensus sequence. The final genomes from a urine sample and a lung sample, the former with an HCMV to human DNA load approximately 50 times greater than the latter, achieved 99.97 and 99.93% identity, respectively, to the benchmark genomes obtained independently by Illumina sequencing. Thus, we demonstrated that nanopore sequencing is capable of determining HCMV genomes directly from high-viral-load clinical samples with a high accuracy.


Assuntos
Citomegalovirus , Sequenciamento por Nanoporos , Humanos , Análise de Sequência de DNA , Citomegalovirus/genética , Biologia Computacional , Software , Sequenciamento de Nucleotídeos em Larga Escala
8.
PLoS One ; 18(4): e0284187, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37053201

RESUMO

OBJECTIVES: The SARS-CoV-2 Alpha variant was associated with increased transmission relative to other variants present at the time of its emergence and several studies have shown an association between Alpha variant infection and increased hospitalisation and 28-day mortality. However, none have addressed the impact on maximum severity of illness in the general population classified by the level of respiratory support required, or death. We aimed to do this. METHODS: In this retrospective multi-centre clinical cohort sub-study of the COG-UK consortium, 1475 samples from Scottish hospitalised and community cases collected between 1st November 2020 and 30th January 2021 were sequenced. We matched sequence data to clinical outcomes as the Alpha variant became dominant in Scotland and modelled the association between Alpha variant infection and severe disease using a 4-point scale of maximum severity by 28 days: 1. no respiratory support, 2. supplemental oxygen, 3. ventilation and 4. death. RESULTS: Our cumulative generalised linear mixed model analyses found evidence (cumulative odds ratio: 1.40, 95% CI: 1.02, 1.93) of a positive association between increased clinical severity and lineage (Alpha variant versus pre-Alpha variants). CONCLUSIONS: The Alpha variant was associated with more severe clinical disease in the Scottish population than co-circulating lineages.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Estudos Retrospectivos , Escócia/epidemiologia , Genômica
9.
Nature ; 617(7961): 555-563, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36996873

RESUMO

An outbreak of acute hepatitis of unknown aetiology in children was reported in Scotland1 in April 2022 and has now been identified in 35 countries2. Several recent studies have suggested an association with human adenovirus with this outbreak, a virus not commonly associated with hepatitis. Here we report a detailed case-control investigation and find an association between adeno-associated virus 2 (AAV2) infection and host genetics in disease susceptibility. Using next-generation sequencing, PCR with reverse transcription, serology and in situ hybridization, we detected recent infection with AAV2 in plasma and liver samples in 26 out of 32 (81%) cases of hepatitis compared with 5 out of 74 (7%) of samples from unaffected individuals. Furthermore, AAV2 was detected within ballooned hepatocytes alongside a prominent T cell infiltrate in liver biopsy samples. In keeping with a CD4+ T-cell-mediated immune pathology, the human leukocyte antigen (HLA) class II HLA-DRB1*04:01 allele was identified in 25 out of 27 cases (93%) compared with a background frequency of 10 out of 64 (16%; P = 5.49 × 10-12). In summary, we report an outbreak of acute paediatric hepatitis associated with AAV2 infection (most likely acquired as a co-infection with human adenovirus that is usually required as a 'helper virus' to support AAV2 replication) and disease susceptibility related to HLA class II status.


Assuntos
Infecções por Adenovirus Humanos , Dependovirus , Hepatite , Criança , Humanos , Doença Aguda/epidemiologia , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/genética , Infecções por Adenovirus Humanos/virologia , Alelos , Estudos de Casos e Controles , Linfócitos T CD4-Positivos/imunologia , Coinfecção/epidemiologia , Coinfecção/virologia , Dependovirus/isolamento & purificação , Predisposição Genética para Doença , Vírus Auxiliares/isolamento & purificação , Hepatite/epidemiologia , Hepatite/genética , Hepatite/virologia , Hepatócitos/virologia , Cadeias HLA-DRB1/genética , Cadeias HLA-DRB1/imunologia , Fígado/virologia
10.
Nature ; 617(7961): 564-573, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36996872

RESUMO

Since its first identification in Scotland, over 1,000 cases of unexplained paediatric hepatitis in children have been reported worldwide, including 278 cases in the UK1. Here we report an investigation of 38 cases, 66 age-matched immunocompetent controls and 21 immunocompromised comparator participants, using a combination of genomic, transcriptomic, proteomic and immunohistochemical methods. We detected high levels of adeno-associated virus 2 (AAV2) DNA in the liver, blood, plasma or stool from 27 of 28 cases. We found low levels of adenovirus (HAdV) and human herpesvirus 6B (HHV-6B) in 23 of 31 and 16 of 23, respectively, of the cases tested. By contrast, AAV2 was infrequently detected and at low titre in the blood or the liver from control children with HAdV, even when profoundly immunosuppressed. AAV2, HAdV and HHV-6 phylogeny excluded the emergence of novel strains in cases. Histological analyses of explanted livers showed enrichment for T cells and B lineage cells. Proteomic comparison of liver tissue from cases and healthy controls identified increased expression of HLA class 2, immunoglobulin variable regions and complement proteins. HAdV and AAV2 proteins were not detected in the livers. Instead, we identified AAV2 DNA complexes reflecting both HAdV-mediated and HHV-6B-mediated replication. We hypothesize that high levels of abnormal AAV2 replication products aided by HAdV and, in severe cases, HHV-6B may have triggered immune-mediated hepatic disease in genetically and immunologically predisposed children.


Assuntos
Infecções por Adenovirus Humanos , Genômica , Hepatite , Criança , Humanos , Doença Aguda/epidemiologia , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/imunologia , Infecções por Adenovirus Humanos/virologia , Linfócitos B/imunologia , Perfilação da Expressão Gênica , Hepatite/epidemiologia , Hepatite/imunologia , Hepatite/virologia , Imuno-Histoquímica , Fígado/imunologia , Fígado/virologia , Proteômica , Linfócitos T/imunologia
11.
Addiction ; 118(7): 1340-1350, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36808787

RESUMO

BACKGROUND AND AIMS: Chronic infection with the hepatitis C virus (HCV) has a detrimental impact on health-related quality of life (QoL). Scale-up of HCV direct-acting antiviral (DAA) therapy among people who inject drugs (PWID) is underway in several countries since the introduction of interferon-free regimens. This study aimed to assess the impact of DAA treatment success on QoL for PWID. DESIGN: Cross-sectional study using two rounds of the Needle Exchange Surveillance Initiative, a national anonymous bio-behavioural survey and a longitudinal study involving PWID who underwent DAA therapy. SETTING: The setting for the cross-sectional study was Scotland (2017-2018, 2019-2020). The setting for the longitudinal study was the Tayside region of Scotland (2019-2021). PARTICIPANTS: In the cross-sectional study PWID were recruited from services providing injecting equipment (n = 4009). In the longitudinal study, participants were PWID on DAA therapy (n = 83). MEASUREMENTS: In the cross-sectional study, the association between QoL (measured using the EQ-5D-5L quality of life instrument) and HCV diagnosis and treatment was assessed using multilevel linear regression. In the longitudinal study, QoL was compared at four timepoints using multilevel regression, from treatment commencement until 12 months following commencement. FINDINGS: In the cross-sectional study, 41% (n = 1618) were ever chronically HCV infected, of whom 78% (n = 1262) were aware of their status and of whom 64% (n = 704) had undergone DAA therapy. There was no evidence for a marked QoL improvement associated with viral clearance among those treated for HCV (B = 0.03; 95% CI, -0.03 to 0.09). In the longitudinal study, improved QoL was observed at the sustained virologic response test timepoint (B = 0.18; 95% CI, 0.10-0.27), but this was not maintained at 12 months following start of treatment (B = 0.02; 95% CI, -0.05 to 0.10). CONCLUSIONS: Successful direct-acting antiviral therapy for hepatitis C infection may not lead to a durable improvement in quality of life among people who inject drugs, although there may be a transient improvement around the time of sustained virologic response. Economic models of the impact of scaling-up treatment may need to include more conservative quality of life benefits over and above reductions in mortality, disease progression and transmission of infection.


Assuntos
Usuários de Drogas , Hepatite C Crônica , Hepatite C , Abuso de Substâncias por Via Intravenosa , Humanos , Hepacivirus , Antivirais/uso terapêutico , Qualidade de Vida , Abuso de Substâncias por Via Intravenosa/epidemiologia , Hepatite C Crônica/tratamento farmacológico , Estudos Longitudinais , Estudos Transversais , Hepatite C/epidemiologia
12.
Access Microbiol ; 5(12)2023.
Artigo em Inglês | MEDLINE | ID: mdl-38188247

RESUMO

Removing the swab after collection can speed up diagnosis and improve the quality of laboratory procedures. This study investigates the impact of swab removal on SARS-CoV-2 detection in clinical specimens with a focus on high Cycle threshold (Ct) samples (Cts≥32). The method assessed pairs of SARS-CoV-2 samples mimicking combined throat and nose swabs and tested them on two real-time-PCR platforms; the Applied Biosystems 7500 and the Abbott Alinity. Swab removal did not significantly affect detection rates of SARS-CoV-2 samples with Ct values<32, regardless of the PCR platform. However, reduced reproducibility was seen at the endpoint limit of detection of the platforms, which meant that fewer samples with Ct values≥32 were detected in the swab removal group.

13.
Open Forum Infect Dis ; 9(11): ofac531, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36381618

RESUMO

Background: We conducted this study to assess the prevalence of viral coinfection in a well characterized cohort of hospitalized coronavirus disease 2019 (COVID-19) patients and to investigate the impact of coinfection on disease severity. Methods: Multiplex real-time polymerase chain reaction testing for endemic respiratory viruses was performed on upper respiratory tract samples from 1002 patients with COVID-19, aged <1 year to 102 years old, recruited to the International Severe Acute Respiratory and Emerging Infections Consortium WHO Clinical Characterisation Protocol UK study. Comprehensive demographic, clinical, and outcome data were collected prospectively up to 28 days post discharge. Results: A coinfecting virus was detected in 20 (2.0%) participants. Multivariable analysis revealed no significant risk factors for coinfection, although this may be due to rarity of coinfection. Likewise, ordinal logistic regression analysis did not demonstrate a significant association between coinfection and increased disease severity. Conclusions: Viral coinfection was rare among hospitalized COVID-19 patients in the United Kingdom during the first 18 months of the pandemic. With unbiased prospective sampling, we found no evidence of an association between viral coinfection and disease severity. Public health interventions disrupted normal seasonal transmission of respiratory viruses; relaxation of these measures mean it will be important to monitor the prevalence and impact of respiratory viral coinfections going forward.

15.
Viruses ; 14(8)2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-36016300

RESUMO

Direct-acting antivirals (DAAs) have revolutionised the treatment of Hepatitis C virus (HCV), allowing the World Health Organisation (WHO) to set a target of eliminating HCV by 2030. In this study we aimed to investigate glecaprevir and pibrentasvir (GP) treatment outcomes in a cohort of patients with genotype 2a infection. METHODS: Clinical data and plasma samples were collected in NHS Greater Glasgow & Clyde. Next generation whole genome sequencing and replicon assays were carried out at the MRC-University of Glasgow Centre for Virus Research. RESULTS: 132 cases infected with genotype 2a HCV were identified. The SVR rate for this group was 91% (112/123) following treatment with GP. An NS5A polymorphism, L31M, was detected in all cases of g2a infection, and L31M+R353K in individuals that failed treatment. The results showed that R353K was present in 90% of individuals in the Glasgow genotype 2a phylogenetic cluster but in less than 5% of all HCV subtype 2a published sequences. In vitro efficacy of pibrentasvir against sub-genomic replicon constructs containing these mutations showed a 2-fold increase in IC50 compared to wildtype. CONCLUSION: This study describes a cluster of HCV genotype 2a infection associated with a lower-than-expected SVR rate following GP treatment in association with the NS5A mutations L31M+R353K.


Assuntos
Hepatite C Crônica , Hepatite C , Abuso de Substâncias por Via Intravenosa , Ácidos Aminoisobutíricos , Antivirais/uso terapêutico , Benzimidazóis , Ciclopropanos , Combinação de Medicamentos , Genótipo , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Humanos , Lactamas Macrocíclicas , Leucina/análogos & derivados , Filogenia , Prolina/análogos & derivados , Prolina/genética , Pirrolidinas , Quinoxalinas , Escócia/epidemiologia , Sulfonamidas
16.
J Infect Dis ; 227(1): 40-49, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-35920058

RESUMO

Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), humans have been exposed to distinct SARS-CoV-2 antigens, either by infection with different variants, and/or vaccination. Population immunity is thus highly heterogeneous, but the impact of such heterogeneity on the effectiveness and breadth of the antibody-mediated response is unclear. We measured antibody-mediated neutralization responses against SARS-CoV-2Wuhan, SARS-CoV-2α, SARS-CoV-2δ, and SARS-CoV-2ο pseudoviruses using sera from patients with distinct immunological histories, including naive, vaccinated, infected with SARS-CoV-2Wuhan, SARS-CoV-2α, or SARS-CoV-2δ, and vaccinated/infected individuals. We show that the breadth and potency of the antibody-mediated response is influenced by the number, the variant, and the nature (infection or vaccination) of exposures, and that individuals with mixed immunity acquired by vaccination and natural exposure exhibit the broadest and most potent responses. Our results suggest that the interplay between host immunity and SARS-CoV-2 evolution will shape the antigenicity and subsequent transmission dynamics of SARS-CoV-2, with important implications for future vaccine design.


Neutralizing antibodies provide protection against viruses and are generated because of vaccination or prior infections. The main target of anti-SARS-CoV-2 neutralizing antibodies is a protein called spike, which decorates the viral particle and mediates viral entry into cells. As SARS-CoV-2 evolves, mutations accumulate in the spike protein, allowing the virus to escape antibody-mediated immunity and decreasing vaccine effectiveness. Multiple SARS-CoV-2 variants have appeared since the start of the COVID-19 pandemic, causing various waves of infection through the population and infecting­in some cases­people that had been previously infected or vaccinated. Because the antibody response is highly specific, individuals infected with different variants are likely to have different repertoires of neutralizing antibodies. We studied the breadth and potency of the antibody-mediated response against different SARS-CoV-2 variants using sera from vaccinated people as well as from people infected with different variants. We show that potency of the antibody response against different SARS-CoV-2 variants depends on the particular variant that infected each person, the exposure type (infection or vaccination) and the number and order of exposures. Our study provides insight into the interplay between virus evolution and immunity, as well as important information for the development of better vaccination strategies.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Anticorpos , Vacinação , Anticorpos Antivirais , Anticorpos Neutralizantes , Glicoproteína da Espícula de Coronavírus
17.
Nat Microbiol ; 7(8): 1161-1179, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35798890

RESUMO

Vaccines based on the spike protein of SARS-CoV-2 are a cornerstone of the public health response to COVID-19. The emergence of hypermutated, increasingly transmissible variants of concern (VOCs) threaten this strategy. Omicron (B.1.1.529), the fifth VOC to be described, harbours multiple amino acid mutations in spike, half of which lie within the receptor-binding domain. Here we demonstrate substantial evasion of neutralization by Omicron BA.1 and BA.2 variants in vitro using sera from individuals vaccinated with ChAdOx1, BNT162b2 and mRNA-1273. These data were mirrored by a substantial reduction in real-world vaccine effectiveness that was partially restored by booster vaccination. The Omicron variants BA.1 and BA.2 did not induce cell syncytia in vitro and favoured a TMPRSS2-independent endosomal entry pathway, these phenotypes mapping to distinct regions of the spike protein. Impaired cell fusion was determined by the receptor-binding domain, while endosomal entry mapped to the S2 domain. Such marked changes in antigenicity and replicative biology may underlie the rapid global spread and altered pathogenicity of the Omicron variant.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Anticorpos Antivirais , Vacina BNT162 , Humanos , Glicoproteínas de Membrana/metabolismo , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus
18.
Sci Rep ; 12(1): 11735, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35853960

RESUMO

Whole genome sequencing of SARS-CoV-2 has occurred at an unprecedented scale, and can be exploited for characterising outbreak risks at the fine-scale needed to inform control strategies. One setting at continued risk of COVID-19 outbreaks are higher education institutions, associated with student movements at the start of term, close living conditions within residential halls, and high social contact rates. Here we analysed SARS-CoV-2 whole genome sequences in combination with epidemiological data to investigate a large cluster of student cases associated with University of Glasgow accommodation in autumn 2020, Scotland. We identified 519 student cases of SARS-CoV-2 infection associated with this large cluster through contact tracing data, with 30% sequencing coverage for further analysis. We estimated at least 11 independent introductions of SARS-CoV-2 into the student population, with four comprising the majority of detected cases and consistent with separate outbreaks. These four outbreaks were curtailed within a week following implementation of control measures. The impact of student infections on the local community was short-term despite an underlying increase in community infections. Our study highlights the need for context-specific information in the formation of public health policy for higher educational settings.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Surtos de Doenças , Genômica , Planejamento em Saúde , Humanos , SARS-CoV-2/genética , Estados Unidos , Universidades
20.
Drug Alcohol Depend ; 232: 109263, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35120807

RESUMO

BACKGROUND: COVID-19 has likely affected the delivery of interventions to prevent blood-borne viruses (BBVs) among people who inject drugs (PWID). We examined the impact of the first wave of COVID-19 in Scotland on: 1) needle and syringe provision (NSP), 2) opioid agonist therapy (OAT) and 3) BBV testing. METHODS: An interrupted time series study design; 23rd March 2020 (date of the first 'lockdown') was chosen as the key date. RESULTS: The number of HIV tests and HCV tests in drug services/prisons, and the number of needles/syringes (N/S) distributed decreased by 94% (RR=0.062, 95% CI 0.041-0.094, p < 0.001), 95% (RR=0.049, 95% CI 0.034-0.069, p < 0.001) and 18% (RR = 0.816, 95% CI 0.750-0.887, p < 0.001), respectively, immediately after lockdown. Post-lockdown, an increasing trend was observed relating to the number of N/S distributed (0.6%; RR = 1.006, 95% CI 1.001-1.012, p = 0.015), HIV tests (12.1%; RR = 1.121, 95% CI 1.092-1.152, p < 0.001) and HCV tests (13.2%; RR = 1.132, 95 CI 1.106-1.158, p < 0.001). Trends relating to the total amount of methadone prescribed remained stable, but a decreasing trend in the number of prescriptions (2.4%; RR = 0.976, 95% CI 0.959-0.993, p = 0.006) and an increasing trend in the quantity prescribed per prescription (2.8%; RR = 1.028, 95% CI 1.013-1.042, p < 0.001) was observed post-lockdown. CONCLUSIONS: COVID-19 impacted the delivery of BBV prevention services for PWID in Scotland. While there is evidence of service recovery; further effort is likely required to return some intervention coverage to pre-pandemic levels in the context of subsequent waves of COVID-19.


Assuntos
COVID-19 , Usuários de Drogas , Infecções por HIV , Preparações Farmacêuticas , Abuso de Substâncias por Via Intravenosa , COVID-19/epidemiologia , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Análise de Séries Temporais Interrompida , SARS-CoV-2 , Escócia/epidemiologia , Abuso de Substâncias por Via Intravenosa/epidemiologia , Abuso de Substâncias por Via Intravenosa/reabilitação
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