Babies born during the COVID-19 pandemic-related lockdowns had lower rates of allergies, including food allergies and had more gut health benefits, new research from Ireland has found. The long-term impact of the lockdown remains yet to be seen, but it appears that there were significant differences in the gut microbiome development of newborns born during this phase compared to babies born pre-pandemic.
What was the study about?
A study published in Allergy found that newborns from the lockdown period had more beneficial microbes acquired from their mothers after birth — possibly an impact of the lower infection rates and consequent antibiotic use. Besides, the breastfeeding duration increased during this period. According to the authors of the study, titled ‘Association between gut microbiota development and allergy in infants born during pandemic-related social distancing restrictions’, these maternal microbes could be protecting the babies against allergic complications.
According to Royal College of Surgeons in Ireland (RCSI), this is the first study to specifically look into the gut health of newborns from the pandemic period. The research was carried out by researchers from APC Microbiome Ireland (APC), an SFI Research Centre, based in University College Cork, RCSI, University of Medicine and Health Sciences and Children’s Health Ireland in collaboration with University College Cork, University of Helsinki, University of Colorado, Karolinska Institute Stockholm, Children’s Health Ireland, Rotunda Hospital and The Coombe Hospital.
As a part of the study, fecal samples from 351 babies born in the first three months of the pandemic were analyzed and compared with babies born pre-pandemic. Allergy testing was conducted at 12 and 24 months.
The gut microbiome link
Dr Rajath Athreya, lead neonatologist and senior consultant pediatrician, Rainbow Children’s hospital, Sarjapur Road, Bangalore, says that the human gut gets colonized by bacteria very early in life.
“The composition of this gut micitobiota has regulatory effects on our immune system and [is linked to] other health parameters. The composition of the microbiome depends on environmental exposure in the newborn period and early life,” says Dr Athreya. The gut microbiome or the microbes in the human intestinal tract are crucial to overall human health and have been found to be linked to several diseases, including cancer and Parkinson’s Disease. Previous research has also pointed out that the composition of gut microbiota may impact one’s susceptibility to viral lung infections. Studies have also linked alterations in the gut microbiome caused by a low-fiber diet to the rising prevalence of food allergies.
Commenting on the findings of the study, Dr Athreya says, “Sensitization to allergens and allergies have some correlation to gut microbiota. During the pandemic, the exposure to the environment was altered. Hence, this study has tried to look at how the microbiome of infants born during this time differs and if it has any correlation to allergies.”
Effect of social isolation on microbiome development
Professor Jonathan Hourihane, head of department of pediatrics, RCSI and consultant pediatrician, Children’s Health Ireland Temple Street, who is joint senior author of the study, talked about the research’s implications in a statement, where he said that the study offers a new perspective on the impact of social isolation in early life on the gut microbiome. “Notably, the lower allergy rates among newborns during the lockdown could highlight the impact of lifestyle and environmental factors, such as frequent antibiotic use, on the rise of allergic diseases,” Prof Hourihane said. He added that researchers are now hoping to re-examine these children when they turn five years old to assess long-term implications.
According to researchers, while we all start life sterile, communities of beneficial microbes that inhabit our gut develop over the first years of life. The statement mentions that the researchers took the opportunity to study microbiome development in infants raised during the early COVID-19 era when strict social distancing restrictions were in place as the complexity of early life exposures was reduced. This facilitated accurate identification of the key early life exposures.
“Prior to this study, it has been difficult to fully determine the relative contribution of these multiple environmental exposures and dietary factors on early-life microbiome development,” says the statement by Professor Liam O’Mahony, principal investigator at APC Microbiome Ireland and professor of immunology at University College Cork, and joint senior author of the study. “One fascinating outcome is that due to reduced human exposures and protection from infection, only 17% of infants required an antibiotic by one year of age, which correlated with higher levels of beneficial bacteria such as bifidobacteria. The study has provided a rich repository of data, which we will continue to analyze and investigate in the future,” Prof O’Mahony added.
Antibiotic use and breastfeeding
The study points out that only 17% of pandemic babies required antibiotics by the age of one, compared to 80% in a pre-pandemic UK birth cohort.
It has also highlighted breastfeeding as the major determining factor behind the gut microbiome composition of the babies.
Dr Athreya says findings regarding the healthier composition of gut microbiome are not surprising, given the fact that more babies would have spent longer breastfeeding. He adds that there was reduced exposure to other bacteria. Besides, there were also very few instances where antibiotics would’ve been used in these babies which again would hamper healthy gut bacteria.
Takeaways
A new study from Ireland has found that newborns born during the Covid-19-related lockdown had several gut health benefits and developed fewer allergies than expected. Researchers have pointed to reduced antibiotic use and breastfeeding as some of the contributing factors.
