How Five Years of Mapping Diaper Contents Unveiled the Viral Diversity of a Healthy Infant Gut

Image credit:

Recent studies by a team of researchers from COPSAC (Copenhagen Prospective Studies on Asthma in Childhood) and the Department of Food Science at the University of Copenhagen suggest that a healthy infant gut is populated by a vast number of diverse viruses, including many that have not been previously described. This five-year study, led by University of Copenhagen professor Dennis Sandris Nielsen and published in Nature Microbiology, also uncovered a collection of over 10,000 viral species distributed over 248 families – with 232 of them being unknown.

The team of researchers named the remaining 232 unknown viral families after the 647 healthy Danish one-year-olds whose diapers they studied. Thus, newly-discovered viruses now bear names like Sylvesterviridae, Rigmorviridae and Tristanviridae. 90% of these viruses were revealed to be bacteriophages – viruses that attack bacteria and not human cells. This indicates that, as allies to beneficial bacteria, bacteriophages help to ensure a balanced gut microbiome and protect against chronic diseases like asthma and diabetes later in life.

The other 10% of the viruses discovered were identified as eukaryotic – meaning they use human cells as hosts – and may thus be either friend or foe. While these viruses seem to be important for training the immune system, their main function is still largely a mystery.

Looking forward, the research teams are now examining the role of gut viruses in relation to various childhood diseases and exploring where the viruses in one-year-olds come from. Current hypotheses involve exposure to bacteria and viruses both in the mother and in the environment during childbirth. A better understanding of the relationship between bacteria, viruses and the immune system could have great implications in the prevention of chronic diseases.

COPSAC is an interdisciplinary research center at the University of Copenhagen. Established in 2002, the institute focuses on childhood and chronic diseases and has achieved a long list of successful projects and publications. The institute’s mission is to improve the health and lifestyle of both children and adults.

Professor Dennis Sandris Nielsen is a leading figure in the field of food science and has been at the University of Copenhagen for twenty-four years. During his time there, he has published numerous papers and has led a number of large-scale projects related to health and nutrition. His research on infant gut viral diversity is one of many contributions to the medical and scientific world.