Journal Article

Influence of a Serratia marcescens outbreak on the gut microbiota establishment process in low-weight preterm neonates

del Campo, Rosa, Saralegui, Claudia, Escribano, Esperanza, Moles, Laura, Alba, Claudio, Alarcón, Teresa, Lázaro-Perona, Fernando, Montes, María Teresa, Sáenz de Pipaón, Miguel, Rodríguez, Juan Miguel

2019

Overview

Adequate gut microbiota establishment is important for lifelong health. The aim was to sequentially analyze the gut microbiota establishment in low-birth-weight preterm neonates admitted to a single neonatal intensive care unit during their first 3 weeks of life, comparing two epidemiological scenarios. Seven control infants were recruited, and another 12 during a severe S. marcescens outbreak. Meconium and feces from days 7, 14, and 21 of life were collected. Gut microbiota composition was determined by 16S rDNA massive sequencing. Cultivable isolates were genotyped by pulsed-field gel electrophoresis, with four S. marcescens submitted for whole-genome sequencing. The expected bacterial ecosystem expansion after birth is delayed, possibly related to antibiotic exposure. The Proteobacteria phylum dominates, although with marked interindividual variability. The outbreak group considerably differed from the control group, with higher densities of Escherichia coli and Serratia to the detriment of Enterococcus and other Firmicutes. Curiously, obligate predators were only detected in meconium and at very low concentrations. Genotyping of cultivable bacteria demonstrated the high bacterial horizontal transmission rate that was confirmed with whole-genome sequencing for S. marcescens. Preterm infants admitted at NICU are initially colonized by homogeneous microbial communities, most of them from the nosocomial environment, which subsequently evolve according to the individual conditions. Our results demonstrate the hospital epidemiology pressure, particularly during outbreak situations, on the gut microbiota establishing process.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Age / Analysis / Antibiotics / Babies / Bacteria / Biology and Life Sciences / Birth / Birth weight / Care and treatment / Composition / Cross Infection - microbiology / Disease Outbreaks / DNA sequencing / DNA, Bacterial - genetics / DNA, Bacterial - isolation & purification / DNA, Ribosomal - genetics / E coli / Ecosystems / Electrophoresis / Epidemics / Epidemiology / Escherichia coli / Feces / Feces - microbiology / Female / Gastrointestinal Microbiome - genetics / Gel electrophoresis / Gene sequencing / Genomes / Genomics / Genotyping / Gut microbiota / Health / Health aspects / Hospitals / Humans / Immune system / Infant / Infant, Low Birth Weight - metabolism / Infant, Newborn / Infant, Premature - metabolism / Infants / Influence / Intensive Care Units, Neonatal / Intestinal microflora / Low birth weight / Low concentrations / Male / Meconium / Medicine and Health Sciences / Microbial activity / Microbiota / Microbiota (Symbiotic organisms) / Microorganisms / Neonatal diseases / Neonatal intensive care / Neonates / Newborn babies / Newborn infants / Nosocomial infection / Nosocomial infections / Outbreaks / People and Places / Predators / Premature birth / Premature infants / Pulsed-field gel electrophoresis / Risk factors / rRNA 16S / Sepsis / Serratia / Serratia Infections - microbiology / Serratia marcescens - genetics / Serratia marcescens - growth & development / Serratia marcescens - isolation & purification / Spain / VOCs / Volatile organic compounds / Weight / Whole genome sequencing