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1.
Open Forum Infect Dis ; 10(11): ofad540, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38023535

RESUMO

We compared 2 human papillomavirus (HPV) assays to detect the 14 high-risk HPV (hrHPV) genotypes in self-collected anal samples. We found a good agreement and similar performance to detect HPV-16, HPV-18, and the 12 other hrHPV genotypes. The global performance to detect the 14 hrHPV genotypes was not significantly different between the 2 assays.

4.
Infect Dis Now ; 53(1): 104629, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36323397

RESUMO

OBJECTIVES: We aimed to characterize and compare the viral loads (VL) of the Omicron BA.1 and BA.2 lineages and the Delta variant in nasopharyngeal samples from newly diagnosed COVID-19 patients and their kinetics over time. PATIENTS AND METHODS: The kinetics of the VL were measured on the CT data from 215 SARS-CoV-2 positive patients who presented at least two positive PCRs a day apart and were screened for SARS-CoV-2 viral lineages. RESULTS: We observed no significant difference in median CT value during the first diagnostic test between the Delta variant and the two Omicron lineages. However, the kinetics of CT decreases for the BA.1 and BA.2 lineage were significantly lengthier in time than the kinetics for the Delta variant. The BA.2 lineage presented lower median CT value (-2 CT) (inversely proportional to the VL) than the BA.1 lineage. CONCLUSIONS: BA.2 Omicron lineage presented higher VL than BA.1 Omicron lineage at diagnostic. Omicron BA.1 and BA.2 lineages have more prolonged replication than the Delta variant.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Reação em Cadeia da Polimerase
5.
Microbiol Spectr ; 10(5): e0192222, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36125269

RESUMO

Large-scale screening for SARS-CoV-2 infection is an important tool for epidemic prevention and control. The appearance of new variants associated with specific mutations can call into question the effectiveness of rapid diagnostic tests (RDTs) deployed massively at national and international levels. We compared the clinical and virological characteristics of individuals infected by Delta or Omicron variants to assess which factors were associated with a reduced performance of RDT. A commercially available RDT as well as the evaluation of the viral load (VL) and the detection of replicate intermediates (RIs) were carried out retrospectively on positive SARS-CoV-2 nasopharyngeal specimens from health care workers of the Pitié-Salpêtrière Hospital infected by the Delta or Omicron variant between July 2021 and January 2022. Of the 205 samples analyzed (104 from individuals infected with Delta and 101 with Omicron), 176 were analyzed by RDT and 200 by RT-PCR for VL and RIs. The sensitivity of the TDR for Omicron was significantly lower than that observed for Delta (53.8% versus 74.7%, respectively, P < 0.01). Moreover, the Delta VL was significantly higher than that measured for Omicron (median Ct 21.2 versus 24.1, respectively, P < 0.01) and associated with the positivity of the RDT in multivariate analysis. We demonstrate a lower RDT sensitivity associated with a lower VL at the time of diagnosis on Omicron-infected individuals in comparison to those infected with the Delta variant. This RDT lower sensitivity should be taken into account in the large-scale screening strategy and in particular in case of strong suspicion of infection where testing should be repeated. IMPORTANCE Previous reports have shown a variability in the diagnostic performance of RDTs. In the era of SARS-CoV-2 variants and the use of RDT, mutation associated with these variants could affect the test performance. We evaluate the sensitivity of the RDT Panbio COVID-19 Ag (Abbott) with two variants of concern (VOC), the Delta and Omicron variants. In order to investigate whether clinical characteristics or virological characteristics can affect this sensitivity, we collected clinical information and performed a specific RT-PCR that detected the RIs as a marker of the viral replication and viral cycle stage. Our results showed that Omicron was less detected than the Delta variant. A lower viral load of Omicron variant in comparison to Delta variant explained this decreased sensitivity, even if they are at the same stage of the disease and the viral cycle and should be taken into account with the use of RDT as diagnostic tool.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Carga Viral , Estudos Retrospectivos , Sensibilidade e Especificidade , COVID-19/diagnóstico
6.
Microorganisms ; 11(1)2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36677322

RESUMO

SARS-CoV-2 expresses on its surface the Spike protein responsible for binding with the ACE2 receptor and which carries the majority of immunodominant epitopes. Mutations mainly affect this protein and can modify characteristics of the virus, giving each variant a unique profile concerning its transmissibility, virulence, and immune escape. The first lineage selected is the B.1 lineage characterized by the D614G substitution and from which all SARS-CoV-2 variants of concern have emerged. The first three variants of concern Alpha, Beta, and Gamma spread in early 2021: all shared the N501Y substitution. These variants were replaced by the Delta variant in summer 2021, carrying unique mutations like the L452R substitution and associated with higher virulence. It was in turn quickly replaced by the Omicron variant at the end of 2021, which has predominated since then, characterized by its large number of mutations. The successive appearance of variants of concern showed a dynamic evolution of SARS-CoV-2 through the selection and accumulation of mutations. This has not only allowed progressive improvement of the transmissibility of SARS-CoV-2, but has also participated in a better immune escape of the virus. This review brings together acquired knowledge about SARS-CoV-2 variants of concern and the impacts of the Spike mutations.

7.
Infect Dis Now ; 51(4): 383-386, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33490993

RESUMO

INTRODUCTION: Invasive pulmonary aspergillosis is a well-known complication of acute respiratory distress syndrome, the most serious manifestation of COVID-19. Four recent studies have reported its incidence among ICU COVID-19 patients. However, they do not share the same case definition, and have provided conflicting results. In this paper we have aimed at reported the incidence of invasive pulmonary aspergillosis for COVID-19 patients in our ICU, and at comparing the different definitions in order to assess their respective relevance. METHODS: Retrospective cohort study of critically ill patients with severe COVID-19 requiring ICU management between 1st March and 30th April 2020. RESULTS: Our results showed significantly lower incidence of invasive pulmonary aspergillosis (1.8%;1/53), compared to three out of four previous studies, and wide variation in the numbers of cases with regard to the different definitions. CONCLUSION: Large-scale studies are needed for a better definition and a more accurate estimation of invasive pulmonary aspergillosis coinfection during COVID-19.


Assuntos
COVID-19/complicações , Aspergilose Pulmonar Invasiva/etiologia , Idoso , Estudos de Coortes , Estado Terminal , Feminino , Humanos , Incidência , Aspergilose Pulmonar Invasiva/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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