COVID-19 and the neonatal microbiome: will the pandemic cost infants their microbes?

Abstract

Mortality and morbidity from infections in children remains low, including an exceedingly low rate of horizontal and vertical transmission. However, unforeseen complications to childhood health have emerged secondary to the pandemic. Few studies to date have examined unintended complications of the pandemic in newborns and infants. In this Commentary, we discuss the impact that COVID-19 may have on inheritance of the newborn microbiome and its assembly throughout the first years of life. In the early stages of the pandemic when vertical transmission of COVID-19 was poorly understood, several studies reported increased rates of C-sections in COVID-19 positive women. Initial recommendations discouraged COVID-19 positive mothers from breastfeeding and participating in skin-to-skin care, advising them to isolate during their window of infectivity. These shifts in perinatal care can adversely impact microbial colonization during the first 1000 days of life. While obstetrical and neonatal management have evolved to reflect our current knowledge of perinatal transmission, we are observing other changes in early life exposures of infants, including increased attention to hygiene, fewer social interactions, and decreased global travel, all of which are major drivers of early-life gut colonization. Composition of the gut microbiota in adults directly impacts severity of infection, suggesting a role of microbial communities in modulating immune responses to COVID-19. Conversely, the role of the intestinal microbiome in susceptibility and severity of COVID-19 in newborns and children remains unknown. The onset of adulthood diseases is related to the establishment of a healthy gut microbiome during childhood. As we continue to define COVID-19 biology, further research is necessary to understand how acquisition of the neonatal microbiome is affected by the pandemic. Furthermore, infection control measures must be balanced with strategies that promote microbial diversity to impart optimal health outcomes and potentially modulate susceptibility of children to

Composition of Human Breast Milk Microbiota and Its Role in Children’s Health

“…Even if transmission of COVID-19 through breastfeeding appears unlikely, the infection could affect HMM, with breast milk being an expression of connection between mother and child [ 35 ]. During pregnancy, intestinal dysbiosis associated with COVID-19 inflammation could affect the composition of a newborn’s pioneer bacterial communities [ 8 ]. It was observed that greater the severity of the disease, greater was the intestinal dysbiosis.…”

“…We can hypothesize that the above findings might be partially applicable to COVID-19 affected pregnant women, and since it is supposed that composition of the breast milk impacts the infant’s intestine, further studies on the changes in the microbiota of pregnant women affected by COVID-19 are necessary [ 35 ]. What is certain is that the pandemic has influenced HMM composition in several phases, both directly and indirectly, which can be substantiated by the fact that the placentas of women affected by severe acute respiratory syndrome have increased rates of vascular malperfusion features that can alter normal bacterial exchange between the mother and child [ 8 ]. Moreover, the presence of respiratory infection, enhances the probability of a C-section delivery, with a consequential reduction in maternal transfer of vaginal microbes to newborns [ 8 ].…”

“…Early intestinal microbial dysbiosis, as that occurring during pregnancy, can affect the composition of the newborn’s pioneer bacterial communities [ 8 ], and this can act as a risk factor for development of diseases such as obesity and asthma in the future [ 9 ], as well as for pathologies such as necrotizing enterocolitis (NEC) in the first few months of life, especially in preterm infants [ 10 ].…”

Development of the Gastrointestinal Tract in Newborns as a Challenge for an Appropriate Nutrition: A Narrative Review

“…Other studies, on the other hand, are focusing on the impact that maternal factors, antibiotic use, host genetics, ethnicity, and even COVID-19 infection can have on microbiota development [ 102 , 103 , 104 ]. Therefore, alterations of the intestinal ecosystem, known as dysbiosis, during this critical period of development are often associated with various kinds of pathologies.…”

Global research priorities for COVID-19 in maternal, reproductive and child health: Results of an international survey

“…Identifying the potential routes of mother-to-child-transmission of COVID-19 is of particular importance for healthcare professionals to be able to provide appropriate care and advice for pregnant and breastfeeding women to minimize the risks posed to their infant. Additionally, understanding the impact of maternal COVID-19 infection on the development of the neonatal microbiome will also be important in providing appropriate nutritional support for these children during infancy [49]. It is well known that some viral infections during pregnancy can have devastating effects on the developing fetus, yet there have been few large-scale studies which involve the collection of samples from pregnant women infected with COVID-19 to determine the routes through which the virus, and immunity to the virus, can be passed from mother to child.…”