Vertical Transmission and Antifungal Susceptibility Profile of Yeast Isolates from the Oral Cavity, Gut, and Breastmilk of Mother–Child Pairs in Early Life

Abstract

Yeast acquisition begins at birth; however, the contribution of the mother on yeast transmission to the offspring and associated resistance is yet to be clarified. The aim of this study was to explore the vertical transmission of yeasts and their antifungal susceptibility profile in early life. Oral, fecal, and breastmilk samples were collected from 73 mother–child pairs four to twelve weeks after delivery and cultured on Sabouraud dextrose agar with chloramphenicol. The isolates were identified by MALDI-TOF MS. The vertical transmission was studied by microsatellite genotyping. Antifungal susceptibility was determined for fluconazole, voriconazole, miconazole, anidulafungin, and nystatin by broth microdilution assay, following CLSI–M60 guidelines. A total of 129 isolates were identified from 53% mother–child pairs. We verified the vertical transmission of Candida albicans (n = three mother–child pairs) and Candida parapsilosis (n = one mother–child pair) strains, including an antifungal resistant strain transmitted from breastmilk to the gut of a child. Most isolates were susceptible to the tested antifungals, with the exception of four C. albicans isolates and one R. mucilaginosa isolate. The vertical transmission of yeasts happens in early life. This is the first work that demonstrated the role of the mother as a source of transmission of antifungal-resistant yeasts to the child.

Multilocus sequence typing of Candida albicans oral isolates reveals high genetic relatedness of mother-child dyads in early life

“…Moreover, infants in the C . albicans positive group showed a higher likelihood of having a documented history of oral thrush diagnosis and previous use of antifungal medications, aligning with the results reported by Azevedo et al [ 64 ]. Oral thrush is a common infection in early life, affecting 4%-15% of healthy children [ 65 , 66 ], with C .…”

“…Further research is needed to clarify the relationship between feeding methods and Candida colonization in infants and children. Moreover, infants in the C. albicans positive group showed a higher likelihood of having a documented history of oral thrush diagnosis and previous use of antifungal medications, aligning with the results reported by Azevedo et al [64]. Oral thrush is a common infection in early life, affecting 4%-15% of healthy children [65,66], with C. albicans often being the opportunistic microorganism responsible for the infection [67].…”

Intracellular presence and genetic relationship of Helicobacter pylori within neonates' fecal yeasts and their mothers' vaginal yeasts

“…More recently, Ward et al (2018) reported that key body‐site‐specific taxa were impacted by birth mode. Azevedo et al (2023) demonstrated that vertical transmission of yeasts happens in early life and the role of the mother as a source of transmission of yeasts to the child. As vaginal yeast regularly occurs and is transmitted from the mother to neonate during delivery, we assumed that the H. pylori hosted by yeast also follows this transmission route.…”