Antonin Bal
A5054115135- SARS-CoV-2 and COVID-19 Research
- SARS-CoV-2 detection and testing
- COVID-19 Clinical Research Studies
- Respiratory viral infections research
- Viral gastroenteritis research and epidemiology
- Animal Virus Infections Studies
- Influenza Virus Research Studies
- Bacteriophages and microbial interactions
- COVID-19 epidemiological studies
- Virus-based gene therapy research
- Bacillus and Francisella bacterial research
- Long-Term Effects of COVID-19
- Data-Driven Disease Surveillance
- Bacterial Infections and Vaccines
- Diabetic Foot Ulcer Assessment and Management
- CRISPR and Genetic Engineering
- Evolution and Genetic Dynamics
- Immunotherapy and Immune Responses
- Wound Healing and Treatments
- interferon and immune responses
- Plant Virus Research Studies
- Herpesvirus Infections and Treatments
- Viral Infections and Immunology Research
- COVID-19 and healthcare impacts
- Immune responses and vaccinations
Hospices Civils de Lyon
2015-2025
Centre International de Recherche en Infectiologie
2018-2025
Inserm
2016-2025
Université Claude Bernard Lyon 1
2015-2025
Virologie et Pathologies Humaines
2016-2025
École Normale Supérieure de Lyon
2020-2025
Centre National de la Recherche Scientifique
2016-2025
Laboratoire National de Référence
2025
Bristol-Myers Squibb (Germany)
2025
Hôpital de la Croix-Rousse
2019-2024
<ns3:p>Late in 2020, two genetically-distinct clusters of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with mutations biological concern were reported, one the United Kingdom and South Africa. Using a combination data from routine surveillance, genomic sequencing international travel we track dispersal lineages B.1.1.7 B.1.351 (variant 501Y-V2). We account for potential biases surveillance efforts by including passenger volumes location where lineage was first London Africa...
We report the strategy leading to first detection of variant concern 202012/01 (VOC) in France (21 December 2020). First, spike (S) deletion H69–V70 (ΔH69/ΔV70), identified certain SARS-CoV-2 variants including VOC, is screened for. This associated with a S-gene target failure (SGTF) three-target RT-PCR assay (TaqPath kit). Subsequently, SGTF samples are whole genome sequenced. approach revealed mutations co-occurring ΔH69/ΔV70 S:N501Y VOC.
<ns3:p>Late in 2020, two genetically-distinct clusters of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with mutations biological concern were reported, one the United Kingdom and South Africa. Using a combination data from routine surveillance, genomic sequencing international travel we track dispersal lineages B.1.1.7 B.1.351 (variant 501Y-V2). We account for potential biases surveillance efforts by including passenger volumes location where lineage was first London Africa...
Following severe adverse reactions to the AstraZeneca ChAdOx1-S-nCoV-19 vaccine1,2, European health authorities recommended that patients under age of 55 years who received one dose receive a second Pfizer BNT162b2 vaccine as booster. However, effectiveness and immunogenicity this vaccination regimen have not been formally tested. Here we show heterologous combination confers better protection against acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection than homologous in...
Abstract Since the beginning of COVID-19 outbreak, SARS-CoV-2 whole-genome sequencing (WGS) has been performed at unprecedented rate worldwide with use very diverse Next-Generation Sequencing (NGS) methods. Herein, we compare performance four NGS-based approaches for WGS. Twenty-four clinical respiratory samples a large scale Ct values (from 10.7 to 33.9) were sequenced Three used Illumina sequencing: an in-house metagenomic NGS (mNGS) protocol and two newly commercialised kits including...
IFN-I and IFN-III immunity in the nasal mucosa is poorly characterized during SARS-CoV-2 infection. We analyze IFN-I/III signature, namely expression of ISGF-3-dependent IFN-stimulated genes, mildly symptomatic COVID-19 patients show its correlation with serum IFN-α2 levels, which peak at symptom onset return to baseline from day 10 onward. Moreover, signature correlates nasopharyngeal viral load associated presence infectious viruses. By contrast, we observe low scores despite high loads a...
Background Early detection and characterisation of SARS-CoV-2 variants have been continue to be essential for assessing their public health impact. In August 2023, Santé publique France implemented enhanced surveillance BA.2.86 sub-lineage JN.1 because genetic divergence from other increased prevalence. Aim To detail how combining epidemiological laboratory data sources, targeted investigations modelling enabled comprehensive JN.1. Methods Data were collected using a standardised...
A reliable diagnostic assay is crucial to early detect new COVID-19 cases and limit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission. Since the onset of pandemic, World Health Organization has published several molecular approaches developed by referral laboratories, including Charité (Germany), HKU (Hong Kong), China CDC (China), US (United States), Institut Pasteur, Paris (France). We aimed compare sensitivity specificity these different RT-PCR assays using...
Abstract Background The association between SARS-CoV-2 commercial serological assays and virus neutralization test (VNT) has been poorly explored in mild patients with COVID-19. Methods 439 serum specimens were longitudinally collected from 76 healthcare workers RT-PCR-confirmed clinical sensitivity (determined weekly) of 9 evaluated. Clinical specificity was assessed using 69 pre-pandemic sera. Correlation, agreement, concordance the VNT also on a subset 170 samples. Area under ROC curve...
The emergence of SARS-CoV-2 variant 20I/501Y.V1 (VOC-202012/1 or GR/501Y.V1) is concerning given its increased transmissibility. We reanalysed 11,916 PCR-positive tests (41% all positive tests) performed on 7-8 January 2021 in France. prevalence was 3.3% among nationwide and 6.9% the Paris region. Analysing recent rise 20I/501Y.V1, we estimate that, French context, 52-69% more transmissible than previously circulating lineages, depending modelling assumptions.
We aimed to investigate the first Omicron cases detected in France order assess case characteristics and provide supporting information on possible impact of this variant healthcare system. A standardized questionnaire was used collect from confirmed probable cases. Median age 468 investigated 35 years, 376 were symptomatic (89%); 64% vaccinated with two doses 7% had received three doses. Loss smell taste reported by 8.3% 9% cases, respectively. Seven hospitalized, those unvaccinated...
Life-threatening “breakthrough” cases of critical COVID-19 are attributed to poor or waning antibody (Ab) response SARS-CoV-2 vaccines in individuals already at risk. Preexisting auto-Abs neutralizing type I IFNs underlie least 15% pneumonia unvaccinated individuals; their contribution hypoxemic breakthrough vaccinated people is unknown. We studied a cohort 48 (aged 20 86 years) who received two doses messenger RNA (mRNA) vaccine and developed infection with 2 weeks 4 months later. Ab levels...
High viral load in upper respiratory tract specimens observed for Delta cases might contribute to its increased infectivity compared the other variant. However, it is not yet documented if Omicron variant's enhanced also related a higher load. Our aim was determine spread loads variant.Nasopharyngeal swabs, 129 (Omicron) and 85 (Delta), from Health Care Workers were collected during December 2021 at University Hospital of Lyon, France. Cycle threshold (Ct) RdRp target cobas® 6800 SARS-CoV-2...
Abstract From December 2021-February 2022, an intense and unprecedented co-circulation of SARS-CoV-2 variants with high genetic diversity raised the question possible co-infections between how to detect them. Using 11 mixes Delta:Omicron isolates at different ratios, we evaluated performance 4 sets primers used for whole-genome sequencing developed unbiased bioinformatics method detection involving genetically distinct lineages. Applied on 21,387 samples collected 6, 2021 February 27, 2022...
To describe Delta/Omicron SARS-CoV-2 variants co-infection detection and confirmation during the fifth wave of COVID-19 pandemics in France 7 immunocompetent epidemiologically unrelated patients.
Immune memory is influenced by the frequency and type of antigenic challenges. Here, we performed a cross-sectional comparison immune parameters following BA.1 breakthrough infection in individuals with prior hybrid immunity (conferred vaccination) versus those solely vaccinated cohort health care workers Lyon, France. The results showed higher levels serum anti-receptor binding domain (RBD) antibodies neutralizing against post-infection vaccine-only group. Individuals this group also...
Influenza circulates at high levels in Europe since November 2024. Using a test-negative study based on data from French community laboratories between October 2024 and February 2025, we estimated vaccine effectiveness (VE) against PCR-detected influenza infection (44,420/15,052; positive/negative individuals). For all age groups, the overall VE was 42% (95% CI: 37–46%), with 26% 18–34%) A 75% 66–82%) B. Among individuals ≥ 65-year-olds 22% 13–30%) among 0–64-year-olds, 60% 56–65%).
In recent years, metagenomic Next-Generation Sequencing (mNGS) has increasingly been used for an accurate assumption-free virological diagnosis. However, the systematic workflow evaluation on clinical respiratory samples and implementation of quality controls (QCs) is still lacking. A total 3 QCs were implemented processed through whole mNGS workflow: a no-template-control to evaluate contamination issues during process; internal external QC check integrity reagents, equipment, presence...
During routine molecular surveillance of SARS-CoV-2 performed at the National Reference Center Respiratory Viruses (Lyon, France) (n = 229 sequences collected February–April 2020), two frameshifting deletions were detected in open reading frame 6, same position (27267). While a 26-nucleotide deletion variant (D26) was only found one nasopharyngeal sample March 2020, 34-nucleotide (D34) within single geriatric hospital unit 5/9 patients and health care worker April 2020. Phylogeny analysis...