Could a parent’s hospital job shape a child’s nasal microbiome?

Researchers compared nasal microbial communities in young children with and without healthcare-worker parents to examine whether occupational exposures might extend into the home and influence early-life microbial environments.

Study: Bringing work home: the microbiota of children of healthcare workers. Image Credit: MP Art / Shutterstock

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In a recent study published in the journal Pediatric Research, researchers examined the associations between parents' healthcare work and children's nasal microbiota composition.

Healthcare workers (HCWs) carry hospital-related microorganisms on their clothing, personal items, and skin, which can potentially affect the home microbial milieu. Early microbial exposures may help shape the infant microbiota. The potential links between parents' healthcare work and infant microbiota have yet to be investigated.

About the study

In the present study, researchers evaluated associations between parents' healthcare work and children's nasal microbiota composition. Parents and their six- to 24-month-old children were enrolled in two groups: children of HCWs and those of non-HCWs. Families were excluded if children had been born by cesarean delivery, were premature, had not been breastfed, had a chronic illness, or had recent infection, hospitalization, or antibiotic/probiotic use.

Nasal swab samples from both parents and children, along with sociodemographic data, were collected. Microbial deoxyribonucleic acid (DNA) was extracted from samples, and 16S ribosomal ribonucleic acid (rRNA) gene sequencing targeting the V3-V4 regions was performed. Alpha diversity was evaluated using the Shannon index, Chao1, Faith's phylogenetic diversity, and observed species. Beta diversity was assessed using weighted and unweighted UniFrac distances.

A multivariable regression analysis of covariance model assessed children's alpha diversity and taxa abundance, adjusting for sex, age, kindergarten attendance, and siblings. Parent analyses used linear mixed-effects models adjusted for sex, age, smoking status, and body mass index, with family as a random effect. The Benjamini-Hochberg correction was applied with a 0.20 false discovery rate threshold for this exploratory study. Permutational multivariate analysis of variance was used to evaluate beta diversity.

Findings

a Barplot showing the composition of the microbiota at genus level for individual samples. Low abundant genera (i.e., : <1% on average) are summed up into the “Other” category. b Boxplot depicting alpha-diversity comparison between no HW and HW groups for the “Observed species” (P = 0.001) metrics. Individual values for the 37 samples are superimposed to the plot. The green square represents the mean (with 95% CI) value estimated by a multivariable regression ANCOVA model adjusted for age, sex, siblings (yes/no) and kindergarten (yes/no). c Beta-diversity Principal Coordinate Analysis (PCoA) plot derived from the weighted UniFrac distance. Each point represents a sample, colored according to the experimental group, the centroid is the mean coordinate per group and the ellipse is the SEM-based confidence interval. Coordinates 1 and 3 are represented. d Barplots of the geometric mean of the relative abundance of bacterial genera for some selected genera over the experimental groups. Genera with FDR < 0.2 are indicated by a ★. e Boxplot of the distribution of unweighted UniFrac distances between each child and his/her parents divided by the latter being HW or no HW. Individual values are superimposed to the plot.

Conclusions

The clinical meaning remains unclear because respiratory and allergic outcomes were not assessed, so the differences could be harmful, protective, or clinically neutral.

The study’s limitations include its exploratory, pilot nature, cross-sectional design, small sample size, and sole focus on the nasal microbiota. Some child swabs yielded relatively few bacterial reads, and incomplete feeding and sibling data may have left residual confounding.

Journal reference:

• Ferrari L, Severgnini M, Cugliari M, Favero C, Alberzoni M, Milani GP (2026). Bringing work home: the microbiota of children of healthcare workers. Pediatric Research. DOI: 10.1038/s41390-026-05474-7, https://www.nature.com/articles/s41390-026-05474-7