The gut microbiome of infants who were exposed in utero to Hurricane Maria: reduced diversity dependent on breastfeeding. HOLA gut microbiome

Although the infant gut microbiome is a potentially important mechanism linking prenatal exposure to extreme weather disasters and increased disease risks, whether prenatal disaster exposures are associated with alterations in the offspring gut microbiome remains unknown. Our Hurricane as the Origin of Later Alterations in microbiome (HOLA) study included term vaginally born infants aged two to six months, with n=29 infants who were exposed in utero to Hurricane Maria in Puerto Rico and n=34 infants who were conceived at least five months after the Hurricane as controls. Shotgun metagenomic sequencing of infant stool swab samples found that infants exposed in utero to Hurricane Maria had reduced commensals and microbial diversity, as well as an altered gut metabolic potential compared to the control group. The influence of a prenatal disaster exposure on the gut microbiome was the strongest in infants exclusively formula-fed and diminished in the context of exclusive or partial breastfeeding.