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1.
Lancet Microbe ; 5(7): 655-668, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38703782

RESUMO

BACKGROUND: A SARS-CoV-2 controlled human infection model (CHIM) has been successfully established in seronegative individuals using a dose of 1×101 50% tissue culture infectious dose (TCID50) pre-alpha SARS-CoV-2 virus. Given the increasing prevalence of seropositivity to SARS-CoV-2, a CHIM that could be used for vaccine development will need to induce infection in those with pre-existing immunity. Our aim was to find a dose of pre-alpha SARS-CoV-2 virus that induced infection in previously infected individuals. METHODS: Healthy, UK volunteers aged 18-30 years, with proven (quantitative RT-PCR or lateral flow antigen test) previous SARS-CoV-2 infection (with or without vaccination) were inoculated intranasally in a stepwise dose escalation CHIM with either 1×101, 1×102, 1×10³, 1×104, or 1×105 TCID50 SARS-CoV-2/human/GBR/484861/2020, the same virus used in the seronegative CHIM. Post-inoculation, volunteers were quarantined in functionally negative pressure rooms (Oxford, UK) for 14 days and until 12-hourly combined oropharyngeal-nasal swabs were negative for viable virus by focus-forming assay. Outpatient follow-up continued for 12 months post-enrolment, with additional visits for those who developed community-acquired SARS-CoV-2 infection. The primary objective was to identify a safe, well tolerated dose that induced infection (defined as two consecutive SARS-CoV-2 positive PCRs starting 24 h after inoculation) in 50% of seropositive volunteers. This study is registered with ClinicalTrials.gov (NCT04864548); enrolment and follow-up to 12 months post-enrolment are complete. FINDINGS: Recruitment commenced on May 6, 2021, with the last volunteer enrolled into the dose escalation cohort on Nov 24, 2022. 36 volunteers were enrolled, with four to eight volunteers inoculated in each dosing group from 1×101 to 1×105 TCID50 SARS-CoV-2. All volunteers have completed quarantine, with follow-up to 12 months complete. Despite dose escalation to 1×105 TCID50, we were unable to induce sustained infection in any volunteers. Five (14%) of 36 volunteers were considered to have transient infection, based on the kinetic of their PCR-positive swabs. Transiently infected volunteers had significantly lower baseline mucosal and systemic SARS-CoV-2-specific antibody titres and significantly lower peripheral IFNγ responses against a CD8+ T-cell SARS-CoV-2 peptide pool than uninfected volunteers. 14 (39%) of 36 volunteers subsequently developed breakthrough infection with the omicron variant after discharge from quarantine. Most adverse events reported by volunteers in quarantine were mild, with fatigue (16 [44%]) and stuffy nose (16 [44%]) being the most common. There were no serious adverse events. INTERPRETATION: Our study demonstrates potent protective immunity induced by homologous vaccination and homologous or heterologous previous SARS-CoV-2 infection. The community breakthrough infections seen with the omicron variant supports the use of newer variants to establish a model with sufficient rate of infection for use in vaccine and therapeutic development. FUNDING: Wellcome Trust and Department for Health and Social Care.


Assuntos
Anticorpos Antivirais , COVID-19 , SARS-CoV-2 , Humanos , Adulto , SARS-CoV-2/imunologia , COVID-19/prevenção & controle , COVID-19/imunologia , Masculino , Adulto Jovem , Reino Unido/epidemiologia , Feminino , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Adolescente , Voluntários Saudáveis , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/efeitos adversos , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Vacinação/métodos
2.
Int J Infect Dis ; 126: 48-53, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36410691

RESUMO

OBJECTIVES: Since May 2022, cases of human monkeypox virus (hMPXV) with human-to-human cross-transmission have significantly increased in nonendemic countries. Our aim was to characterize diagnostic features of patients with confirmed and possible monkeypox to guide future risk stratification and to describe a virtual care model. METHODS: We performed a retrospective case-control study of 140 patients assessed and screened for suspected monkeypox; on hMPXV polymerase chain reaction testing, 70 were confirmed positive, and 70 were negative. Data were compared to generate odds ratios of demographic and clinical features. RESULTS: Patients who tested positive were predominantly cis-male (99%) and self-identified as gay, bisexual, and other men who have sex with men (94%). Lymphadenopathy at presentation was associated with a higher likelihood of a positive result (odds ratio [OR] 7.69 [95% confidence interval (CI) 3.58, 16.51]). Patients who tested positive were more likely to have a rash affecting the genital (OR 5.38 [95% CI 2.57, 11.23]) or buttocks/perianal region (OR 3.79 [1.70, 8.45]) than negative controls. A total of 79% of patients were engaged with a virtual ward follow-up. CONCLUSION: These data can inform a risk-based approach to the management of suspected monkeypox in gay, bisexual, and other men who have sex with men populations. Lymphadenopathy at presentation and the location of the rash were more associated with a positive hMPXV result. Health authorities can consider a virtual ward approach in the hMPHXV outbreak.


Assuntos
Exantema , Linfadenopatia , Mpox , Minorias Sexuais e de Gênero , Humanos , Masculino , Estudos de Casos e Controles , Estudos Retrospectivos , Mpox/diagnóstico , Mpox/epidemiologia , Homossexualidade Masculina , Londres
4.
Future Healthc J ; 8(1): e70-e75, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33791480

RESUMO

Despite huge advances in vaccines, testing and treatments for COVID-19, there is negligible evidence on the perceptions of people hospitalised with COVID-19 about the care they received. To address this, we developed a satisfaction survey for people with COVID-19 admitted to our hospital during the first COVID-19 wave in Liverpool. Of those invited, 98/160 (61%) responded, of whom 94/98 (96%) completed the survey. Respondents rated overall care highly (mean 4.7/5) and 89/94 (95%) reported that they would recommend the hospital to friends and/or family. Most respondents felt safe on the ward (94%), with privacy maintained (93%) and pain well managed (90%). Fewer than two-thirds (63%) of respondents considered themselves adequately consulted regarding medications and side effects. Sleep and food/drink quality were also highlighted as areas for improvement. To overcome the issues raised, we generated a 'COVID-19 practice pointers' poster within an integrated educational bundle on COVID-19 wards. The impact of the bundle on perceptions of people hospitalised with COVID-19 will be evaluated in people hospitalised with COVID-19 in Liverpool in 2021. Whether hospitalised for COVID-19 or other conditions, our survey results are a timely reminder of the importance of involving patients in shaping the care that they receive.

5.
J Infect ; 82(6): 260-268, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33892014

RESUMO

OBJECTIVES: Diagnostic tests for SARS-CoV-2 are important for epidemiology, clinical management, and infection control. Limitations of oro-nasopharyngeal real-time PCR sensitivity have been described based on comparisons of single tests with repeated sampling. We assessed SARS-CoV-2 PCR clinical sensitivity using a clinical and radiological reference standard. METHODS: Between March-May 2020, 2060 patients underwent thoracic imaging and SARS-CoV-2 PCR testing. Imaging was independently double- or triple-reported (if discordance) by blinded radiologists according to radiological criteria for COVID-19. We excluded asymptomatic patients and those with alternative diagnoses that could explain imaging findings. Associations with PCR-positivity were assessed with binomial logistic regression. RESULTS: 901 patients had possible/probable imaging features and clinical symptoms of COVID-19 and 429 patients met the clinical and radiological reference case definition. SARS-CoV-2 PCR sensitivity was 68% (95% confidence interval 64-73), was highest 7-8 days after symptom onset (78% (68-88)) and was lower among current smokers (adjusted odds ratio 0.23 (0.12-0.42) p < 0.001). CONCLUSIONS: In patients with clinical and imaging features of COVID-19, PCR test sensitivity was 68%, and was lower among smokers; a finding that could explain observations of lower disease incidence and that warrants further validation. PCR tests should be interpreted considering imaging, symptom duration and smoking status.


Assuntos
COVID-19 , SARS-CoV-2 , Testes Diagnósticos de Rotina , Humanos , Reação em Cadeia da Polimerase , RNA Viral , Padrões de Referência , Sensibilidade e Especificidade
6.
Wellcome Open Res ; 6: 222, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35118199

RESUMO

Background: The perspectives and experiences of people hospitalised with COVID-19 have been under-reported during the coronavirus pandemic. We developed and conducted a COVID-19 patient satisfaction survey in a large university-affiliated secondary healthcare centre in Liverpool, UK, during Europe's first coronavirus wave (April-June 2020). The survey found that care was rated highly, including among people of Black Asian and Minority Ethnic (BAME) background. However, sleep-quality and communication about medications and discharge-planning were identified as areas for improvement.   Methods: To improve care for people with COVID-19 admitted to our centre, we designed an educational package for healthcare professionals working on COVID-19 wards. The package, implemented in August 2020, included healthcare worker training sessions on providing holistic care and placement of "Practice Pointers" posters. Patient satisfaction was re-evaluated during the second/third COVID-19 waves in Liverpool (September 2020 - February 2021). Results: Across waves, most (95%) respondents reported that they would recommend our hospital to friends and/or family and rated overall care highly. Comparison of the responses of second/third-wave respondents (n=101) with first-wave respondents (n=94) suggested improved patient satisfaction across most care domains but especially those related to having worries and fears addressed and being consulted about medications and their side-effects. Conclusions: People admitted with COVID-19 to our centre in Liverpool, including those from BAME background, rated the care they received highly. A simple education package improved the feedback on care received by respondents between the first and second/third waves. These UK-first findings are informing regional strategies to improve person-centred care of hospitalised people with COVID-19.

7.
Clin Med (Lond) ; 20(6): 590-592, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33199326

RESUMO

While clinical environments are highly focused on COVID-19, reports of missed or delayed treatment for conditions that imitate COVID-19, such as pneumonia caused by the fungus Pneumocystis jirovecii, are emerging. Given the uncertain spectrum of COVID-19 presentations and variable sensitivity of laboratory tests for SARS-CoV-2, there is a risk that, without a high index of suspicion, alternative aetiologies may be overlooked while pursuing a diagnosis of COVID-19. The British HIV Association has been calling for the inclusion of HIV testing in all patients admitted to hospital with suspected COVID-19. In this article we reflect on the importance of including HIV testing to prevent avoidable morbidity and mortality in our patients.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS , Pneumonia por Pneumocystis , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/patologia , Infecções Oportunistas Relacionadas com a AIDS/fisiopatologia , Infecções Oportunistas Relacionadas com a AIDS/terapia , COVID-19 , Infecções por Coronavirus , Diagnóstico Diferencial , Evolução Fatal , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumocystis carinii , Pneumonia por Pneumocystis/diagnóstico , Pneumonia por Pneumocystis/patologia , Pneumonia por Pneumocystis/fisiopatologia , Pneumonia por Pneumocystis/terapia , Pneumonia Viral
9.
Future Microbiol ; 13: 331-343, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29105506

RESUMO

AIM: Serratia marcescens wound infection after snakebite is often associated with aggressive presentations. However, the virulence determinants remain understudied. MATERIALS & METHODS: Whole-genome sequencing was performed on S. marcescens VGH107, an isolate from wound infection secondary to Trimeresurus mucrosquamatus bite. Comparative genomics approach coupled with multivirulent-locus sequencing typing was applied to systematically predict potential virulence factors. RESULTS: Multivirulent-locus sequencing typing indicated VGH107 falls within the cluster of high pathogenic strains. Comparative analysis identified virulence genes unique in VGH107, including ecpD and ecpE genes for periplasmic chaperone-pilus subunit complex and cdiA and cdiB genes for contact-dependent growth inhibition system. CONCLUSION: The data established here provide foundation for further research regarding the virulence and resistance of S. marcescens.


Assuntos
Genoma Bacteriano/genética , Infecções por Serratia/microbiologia , Serratia marcescens/genética , Serratia marcescens/patogenicidade , Mordeduras de Serpentes/microbiologia , Trimeresurus/microbiologia , Infecção dos Ferimentos/microbiologia , Animais , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla/genética , Genes Bacterianos , Humanos , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Filogenia , Análise de Sequência de DNA , Infecções por Serratia/etiologia , Mordeduras de Serpentes/complicações , Taiwan , Fatores de Virulência/genética , Infecção dos Ferimentos/etiologia
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