Association between nasal and nasopharyngeal bacterial colonization in early life and eczema phenotypes. Hu Chen,Duijts Liesbeth,van Meel Evelien R,Looman Kirsten I M,Kiefte-de Jong Jessica C,Pardo Luba M,Hijnen DirkJan,Pasmans Suzanne G M A,de Jongste Johan C,Moll Henriette A,Nijsten Tamar Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology BACKGROUND:An association has been reported between early life Staphylococcus aureus nasal carriage and higher risk of childhood eczema, but it is unclear whether this relationship is causal and associations with other bacterial species are unclear. OBJECTIVE:To examine the associations of early life nasal and nasopharyngeal bacterial carriage with eczema phenotypes, and the direction of any associations identified. METHODS:Among 996 subjects of a population-based prospective cohort study, nasal swabs for Staphylococcus  aureus, and nasopharyngeal swabs for Streptococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenzae were collected and cultured from age 6 weeks to 6 years. Never, early, mid-, late transient and persistent eczema phenotypes were identified from parental-reported physician-diagnosed eczema from age 6 months until 10 years. Multinomial regression models and cross-lagged models were applied. RESULTS:Staphylococcus aureus nasal carriage at 6 months was associated with an increased risk of early transient and persistent eczema (OR (95% CI): 2.69 (1.34, 5.39) and 4.17 (1.12, 15.51)). The associations between Staphylococcus aureus nasal carriage and eczema were mostly cross-sectional, and not longitudinal. No associations of Staphylococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenza nasopharyngeal bacterial carriage with eczema and eczema phenotypes were observed (OR range (95% CI): 0.71 (0.35, 1.44) to 1.77 (0.84, 3.73)). CONCLUSIONS:Early life Staphylococcus aureus nasal carriage, but not Staphylococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenza nasopharyngeal carriage, was associated with early transient and persistent eczema. Staphylococcus aureus nasal carriage and eczema were mostly cross-sectionally associated, and not longitudinally, making a causal relationship in either direction unlikely. 10.1111/cea.13869

Host-Bacterial Crosstalk Determines Staphylococcus aureus Nasal Colonization. Mulcahy Michelle E,McLoughlin Rachel M Trends in microbiology Staphylococcus aureus persistently colonizes the anterior nares of approximately one fifth of the population and nasal carriage is a significant risk factor for infection. Recent advances have significantly refined our understanding of S. aureus-host communication during nasal colonization. Novel bacterial adherence mechanisms in the nasal epithelium have been identified, and novel roles for both the innate and the adaptive immune response in controlling S. aureus nasal colonization have been defined, through the use of both human and rodent models. It is clear that S. aureus maintains a unique, complex relationship with the host immune system and that S. aureus nasal colonization is overall a multifactorial process which is as yet incompletely understood. 10.1016/j.tim.2016.06.012

Human nasal microbiota. Lemon Katherine P Current biology : CB The human nasal passages host a distinct community of microbes. Katherine P. Lemon describes this distinct community, and why it matters so much for human health. 10.1016/j.cub.2020.08.010

Colonization of the Human Nose and Interaction with Other Microbiome Members. Laux Claudia,Peschel Andreas,Krismer Bernhard Microbiology spectrum is usually regarded as a bacterial pathogen due to its ability to cause multiple types of invasive infections. Nevertheless, colonizes about 30% of the human population asymptomatically in the nares, either transiently or persistently, and can therefore be regarded a human commensal as well, although carriage increases the risk of infection. Whereas many facets of the infection processes have been studied intensively, little is known about the commensal lifestyle of . Recent studies highlight the major role of the composition of the highly variable nasal microbiota in promoting or inhibiting colonization. Competition for limited nutrients, trace elements, and epithelial attachment sites, different susceptibilities to host defense molecules and the production of antimicrobial molecules by bacterial competitors may determine whether nasal bacteria outcompete each other. This chapter summarizes our knowledge about mechanisms that are used by for efficient nasal colonization and strategies used by other nasal bacteria to interfere with its colonization. An improved understanding of naturally evolved mechanisms might enable us to develop new strategies for pathogen eradication. 10.1128/microbiolspec.GPP3-0029-2018