Healthcare (Commonwealth Union) – A team of parent-scientists, consisting of scientists from the University College London (UCL), has reviewed existing evidence and found that children who attend nursery tend to fall ill more frequently than those who stay at home. However, these same children usually experience fewer illnesses during their first years at school.
The five authors of the study, published in the journal Clinical Microbiology Reviews, are all parents of young children as well as researchers or clinicians affiliated with University College London, University of Cambridge, Cornell University, and North Middlesex University Hospital. Their aim was to investigate how often nursery-attending children typically become ill, why they are especially susceptible to infections, how this exposure affects their immune systems, and what steps parents can take to reduce the risks.
Co-author Dr Lucy van Dorp, an infectious disease genomics researcher at the UCL Genetics Institute, explained that the project was inspired by personal experience. She noted that the authors, as parents, noticed how frequently their nine children collectively became sick after beginning nursery, prompting them to carry out the first comprehensive review of illness rates among children during their first year in nursery.
Drawing on findings from epidemiology, immunology and vaccination research, the review concludes that repeated illness in the early months of nursery attendance is typical. According to the authors, a one-year-old starting nursery can expect roughly 12 to 15 respiratory infections, about two gastrointestinal illnesses such as diarrhoea and vomiting, and one or two infections that cause rashes during the first year — a pattern that can significantly disrupt the routines of working parents.
Dr van Dorp added that the common experience of parents noticing a surge in infections when their child first begins nursery is supported by scientific evidence.
The study’s corresponding author, Dr Charlotte Houldcroft, a virologist at the University of Cambridge, explained that many parents are familiar with children returning from nursery with illnesses that can make them – and sometimes their families – feel quite unwell, and in some cases even require hospital treatment.
“But it’s important for parents to follow guidelines to keep children home from nursery while unwell – and potentially for another day or two after recovery, depending on the type of infection. While infections during nursery are normal and common, it’s important to do what we can to mitigate their spread.”
Over time, this pattern tends to improve. The almost monthly cycle of respiratory infections usually becomes less frequent as children grow older; older children are less likely to test positive for viruses at any given time and are also less likely to show symptoms.
Dr van Dorp explained that employers should understand that parents of young children will often need to take time off work to look after them when they are unwell. Parents themselves may also fall ill more often during this stage, although this tends to ease as the child gets older.
The researchers found that young children are especially susceptible to illness mainly because their immune systems are still developing. As their bodies gradually build stronger adaptive immune responses, they become better at fighting infections. The study suggests that the high rate of illness is largely linked to the natural spread of common childhood pathogens, rather than poor hygiene or inadequate childcare practices in nurseries.
Co-author Dr Leo Swadling of the UCL Institute of Infection, Immunity & Transplantation noted that newborns initially receive some protection from antibodies passed on by their mothers. However, this protection decreases during the first year of life, making infants—particularly those entering childcare—more vulnerable to infections. He added that frequent illness in early childhood is normal because children’s immune systems are encountering many of these microbes for the first time. In this sense, nursery environments act like a form of “training ground” for the immune system, helping children build stronger defences for the future.
