Biology subjects

Launes, C.

Publications and source records attributed to Launes, C..

2 recordsLinked to original sources

bioRxiv2025

Oral Microbiota Composition in Children and Adults During Spanish COVID-19 Lockdown: Impact of Home Self-Confinement and SARS-CoV-2 infection

BackgroundThe COVID-19 pandemic changed societys habits and customs due to the social restrictions and health measures imposed during the first half of 2020. This study analyzes the composition of the oral microbiota in relation to age, household cohabitation, SARS-CoV-2 infection, and COVID-19 severity among children and adults under home confinement in Barcelona, Spain. MethodsA prospective study conducted involving children and adults confined during the COVID-19 pandemic in the Barcelona Metropolitan Area between April and June 2020 included multiple cases of several participants living within the same family household. Saliva samples were collected from all participants, and microbiota composition was characterized through 16S rRNA gene sequencing. ResultsA total of 142 adults and 265 children living in 121 family households were included in the study. All 142 adults had a prior confirmed SARS-CoV-2 infection, and 20 (14.08%) of them had a history of severe COVID-19. SARS-CoV2 infection was detected in 58/265 (21.89%) of children; all of them were asymptomatic. Oral microbiota composition and diversity did not differ by SARS-CoV-2 infection status in children. In contrast, adults with severe COVID-19 exhibited lower microbiota diversity and distinct microbiota composition compared to those with mild disease symptoms. Age-related differences in oral microbiota composition were marked in the younger children groups. Additionally, cohabiting individuals shared more Amplicon Sequence Variants (ASVs) than non-cohabitants. ConclusionsAge and cohabitation strongly influenced oral microbial composition. Our study demonstrates that oral microbiota composition in adults varies according to COVID-19 severity, whereas such microbial shifts are not observed in asymptomatic pediatric populations, regardless of infection status.

microbiology↗

bioRxiv2018

Pediatric Brainstem Encephalitis Outbreak Investigation with Metagenomic Next-Generation Sequencing

In 2016, Catalonia experienced a pediatric brainstem encephalitis outbreak caused by enterovirus A71 (EV-A71). Conventional testing identified EV in peripheral body sites, but EV was rarely identified in cerebrospinal fluid (CSF). RNA was extracted from CSF (n=20), plasma (n=9), stool (n=15) and nasopharyngeal samples (n=16) from 10 children with brainstem encephalitis or encephalomyelitis and 10 contemporaneous pediatric controls with presumed viral meningitis or encephalitis. Unbiased complementary DNA libraries were sequenced, and microbial pathogens were identified using a custom bioinformatics pipeline. Full-length virus genomes were assembled for phylogenetic analyses. Metagenomic next-generation sequencing (mNGS) was concordant with qRT-PCR for all samples positive by PCR (n=25). In virus-negative samples (n=35), mNGS detected virus in 28.6% (n=10), including 5 CSF samples. mNGS co-detected EV-A71 and another EV in 5 patients. Overall, mNGS increased the proportion of EV-positive samples from 42% (25/60) to 57% (34/60) (McNemars test; p-value = 0.0077). For CSF, mNGS doubled the number of pathogen-positive samples (McNemars test; p-value = 0.074). Using phylogenetic analysis, the outbreak EV-A71 clustered with a neuroinvasive German EV-A71 isolate. Brainstem encephalitis specific, non-synonymous EV-A71 single nucleotide variants were not identified. mNGS demonstrated 100% concordance with clinical qRT-PCR of EV-related brainstem encephalitis and significantly increased the detection of enteroviruses. Our findings increase the probability that neurologic complications observed were virus-induced rather than para-infectious. A comprehensive genomic analysis confirmed that the EV-A71 outbreak strain was closely related to a neuroinvasive German EV-A71 isolate. There were no clear-cut viral genomic differences that discriminated between patients with differing neurologic phenotypes.

microbiology↗