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1.
Infect Dis (Lond) ; 54(7): 529-533, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35348397

RESUMO

BACKGROUND: The global spread of SARS-CoV-2 has necessitated case isolation, with recommended isolation times based on mean time to viral clearance. CASE STUDY: We present a 28-year-old female living with vertically acquired HIV, undergoing chemotherapy for lymphoma who tested SARS-CoV-2-PCR positive for 164 days. The patient had a history of difficulty taking ARVs, with detectable HIV-RNA and CD4 count below 200 × 106 for the 8 years prior to presentation with symptoms. She stopped ARVs 10 months prior to experiencing fevers, night sweats and loose stool, with a viral load of 354,000 copies/ml and CD4 count of 30 × 106. Following no yield on basic investigations, positron emission tomography scan showed diffuse colonic and oesophageal avidity and a caecal biopsy showed diffuse large B-cell lymphoma. She re-started ARVs and underwent five cycles of R-CHOP chemotherapy. Her first positive SARS-CoV-2 PCR test was detected through routine asymptomatic screening. She self-isolated due to repeated positive tests on a further 8 swabs for a total of 164 days until a negative PCR test. She reported feeling low in mood and frustrated by repeated positive tests and the associated lack of social contact or ability to work. Her positive tests prevented in-person review by her HIV team, which impacted her ARV adherence leading to an unplanned break in therapy. CONCLUSIONS: Our case highlights the challenges to physical and mental health faced by patients with prolonged SARS-CoV-2 shedding and the need to develop surrogate markers for infectivity to enable prompt medical and psychological support and accurate advice about the need for isolation.


Assuntos
COVID-19 , Infecções por HIV , Linfoma Difuso de Grandes Células B , Adulto , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , SARS-CoV-2 , Carga Viral , Eliminação de Partículas Virais
2.
Lancet Infect Dis ; 21(9): 1246-1256, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33857406

RESUMO

BACKGROUND: Emergence of variants with specific mutations in key epitopes in the spike protein of SARS-CoV-2 raises concerns pertinent to mass vaccination campaigns and use of monoclonal antibodies. We aimed to describe the emergence of the B.1.1.7 variant of concern (VOC), including virological characteristics and clinical severity in contemporaneous patients with and without the variant. METHODS: In this cohort study, samples positive for SARS-CoV-2 on PCR that were collected from Nov 9, 2020, for patients acutely admitted to one of two hospitals on or before Dec 20, 2020, in London, UK, were sequenced and analysed for the presence of VOC-defining mutations. We fitted Poisson regression models to investigate the association between B.1.1.7 infection and severe disease (defined as point 6 or higher on the WHO ordinal scale within 14 days of symptoms or positive test) and death within 28 days of a positive test and did supplementary genomic analyses in a cohort of chronically shedding patients and in a cohort of remdesivir-treated patients. Viral load was compared by proxy, using PCR cycle threshold values and sequencing read depths. FINDINGS: Of 496 patients with samples positive for SARS-CoV-2 on PCR and who met inclusion criteria, 341 had samples that could be sequenced. 198 (58%) of 341 had B.1.1.7 infection and 143 (42%) had non-B.1.1.7 infection. We found no evidence of an association between severe disease and death and lineage (B.1.1.7 vs non-B.1.1.7) in unadjusted analyses (prevalence ratio [PR] 0·97 [95% CI 0·72-1·31]), or in analyses adjusted for hospital, sex, age, comorbidities, and ethnicity (adjusted PR 1·02 [0·76-1·38]). We detected no B.1.1.7 VOC-defining mutations in 123 chronically shedding immunocompromised patients or in 32 remdesivir-treated patients. Viral load by proxy was higher in B.1.1.7 samples than in non-B.1.1.7 samples, as measured by cycle threshold value (mean 28·8 [SD 4·7] vs 32·0 [4·8]; p=0·0085) and genomic read depth (1280 [1004] vs 831 [682]; p=0·0011). INTERPRETATION: Emerging evidence exists of increased transmissibility of B.1.1.7, and we found increased virus load by proxy for B.1.1.7 in our data. We did not identify an association of the variant with severe disease in this hospitalised cohort. FUNDING: University College London Hospitals NHS Trust, University College London/University College London Hospitals NIHR Biomedical Research Centre, Engineering and Physical Sciences Research Council.


Assuntos
COVID-19/virologia , Genoma Viral , SARS-CoV-2/genética , Índice de Gravidade de Doença , Sequenciamento Completo do Genoma , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Filogenia , Reino Unido , Carga Viral , Eliminação de Partículas Virais
3.
Med ; 2(9): 1093-1109.e6, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34414384

RESUMO

BACKGROUND: Differences in humoral immunity to coronaviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), between children and adults remain unexplained, and the effect of underlying immune dysfunction or suppression is unknown. Here, we sought to examine the antibody immune competence of children and adolescents with prevalent inflammatory rheumatic diseases, juvenile idiopathic arthritis (JIA), juvenile dermatomyositis (JDM), and juvenile systemic lupus erythematosus (JSLE) against the seasonal human coronavirus (HCoV)-OC43 that frequently infects this age group. METHODS: Sera were collected from JIA (n = 118), JDM (n = 49), and JSLE (n = 30) patients and from healthy control (n = 54) children and adolescents prior to the coronavirus disease 19 (COVID-19) pandemic. We used sensitive flow-cytometry-based assays to determine titers of antibodies that reacted with the spike and nucleoprotein of HCoV-OC43 and cross-reacted with the spike and nucleoprotein of SARS-CoV-2, and we compared them with respective titers in sera from patients with multisystem inflammatory syndrome in children and adolescents (MIS-C). FINDINGS: Despite immune dysfunction and immunosuppressive treatment, JIA, JDM, and JSLE patients maintained comparable or stronger humoral responses than healthier peers, which was dominated by immunoglobulin G (IgG) antibodies to HCoV-OC43 spike, and harbored IgG antibodies that cross-reacted with SARS-CoV-2 spike. In contrast, responses to HCoV-OC43 and SARS-CoV-2 nucleoproteins exhibited delayed age-dependent class-switching and were not elevated in JIA, JDM, and JSLE patients, which argues against increased exposure. CONCLUSIONS: Consequently, autoimmune rheumatic diseases and their treatment were associated with a favorable ratio of spike to nucleoprotein antibodies. FUNDING: This work was supported by a Centre of Excellence Centre for Adolescent Rheumatology Versus Arthritis grant, 21593, UKRI funding reference MR/R013926/1, the Great Ormond Street Children's Charity, Cure JM Foundation, Myositis UK, Lupus UK, and the NIHR Biomedical Research Centres at GOSH and UCLH. This work was supported by the Francis Crick Institute, which receives its core funding from Cancer Research UK, the UK Medical Research Council, and the Wellcome Trust.


Assuntos
Doenças Autoimunes , COVID-19 , Coronavirus Humano OC43 , Doenças Reumáticas , Adolescente , Adulto , Anticorpos Antivirais , Formação de Anticorpos , COVID-19/complicações , Criança , Humanos , Imunoglobulina G , Nucleoproteínas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Síndrome de Resposta Inflamatória Sistêmica
4.
Elife ; 102021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34323691

RESUMO

Background: The degree of heterotypic immunity induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains is a major determinant of the spread of emerging variants and the success of vaccination campaigns, but remains incompletely understood. Methods: We examined the immunogenicity of SARS-CoV-2 variant B.1.1.7 (Alpha) that arose in the United Kingdom and spread globally. We determined titres of spike glycoprotein-binding antibodies and authentic virus neutralising antibodies induced by B.1.1.7 infection to infer homotypic and heterotypic immunity. Results: Antibodies elicited by B.1.1.7 infection exhibited significantly reduced recognition and neutralisation of parental strains or of the South Africa variant B.1.351 (Beta) than of the infecting variant. The drop in cross-reactivity was significantly more pronounced following B.1.1.7 than parental strain infection. Conclusions: The results indicate that heterotypic immunity induced by SARS-CoV-2 variants is asymmetric. Funding: This work was supported by the Francis Crick Institute and the Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , COVID-19/epidemiologia , Reações Cruzadas , Humanos , Pais , África do Sul/epidemiologia , Glicoproteína da Espícula de Coronavírus , Reino Unido/epidemiologia
5.
Science ; 370(6522): 1339-1343, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33159009

RESUMO

Zoonotic introduction of novel coronaviruses may encounter preexisting immunity in humans. Using diverse assays for antibodies recognizing SARS-CoV-2 proteins, we detected preexisting humoral immunity. SARS-CoV-2 spike glycoprotein (S)-reactive antibodies were detectable using a flow cytometry-based method in SARS-CoV-2-uninfected individuals and were particularly prevalent in children and adolescents. They were predominantly of the immunoglobulin G (IgG) class and targeted the S2 subunit. By contrast, SARS-CoV-2 infection induced higher titers of SARS-CoV-2 S-reactive IgG antibodies targeting both the S1 and S2 subunits, and concomitant IgM and IgA antibodies, lasting throughout the observation period. SARS-CoV-2-uninfected donor sera exhibited specific neutralizing activity against SARS-CoV-2 and SARS-CoV-2 S pseudotypes. Distinguishing preexisting and de novo immunity will be critical for our understanding of susceptibility to and the natural course of SARS-CoV-2 infection.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/imunologia , Imunidade Humoral , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Animais , COVID-19/sangue , Mapeamento de Epitopos , Feminino , Células HEK293 , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/química , Glicoproteína da Espícula de Coronavírus/química , Zoonoses Virais/sangue , Zoonoses Virais/imunologia , Adulto Jovem
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