Toddlers and pre-schoolers attending nursery will get an average of 15 illnesses in their first year, leading to around 13 days away from childcare, a new study reveals.
However, experts suggest this period acts as an "immune system boot camp", ultimately making children more resilient to bugs when they begin school.
The academics, prompted by their own children's frequent illnesses after starting formal childcare, are calling for employers to show greater understanding of the sickness absences parents and children may face.
Dr Lucy van Dorp, an infectious disease genomics researcher at the UCL Genetics Institute and co-author, said: “As parents, we were all struck by how often our collective nine children became ill after starting nursery. So we came together to do the first review of how often a child starting nursery will get sick in their first year of attendance and what can be done about it.”
Their analysis concluded that in their initial year of formal childcare, babies and young children are likely to experience around 12 respiratory illnesses, two episodes of diarrhoea or vomiting, and at least one rash-related illness.
While nursery children experience more infections aged one to five, this reverses at school, with those without prior childcare falling ill more frequently.
This is because early exposure in group settings builds immunity, protecting during early school years.
The authors wrote in Clinical Microbiology Reviews: “Employers need realistic expectations about the likelihood and frequency of both child and parental/caregiver sickness absence following the end of parental leave.
“Attendance at formal childcare may tip the balance in favour of infection now rather than later.”
Vaccination is one of the most effective ways parents can safeguard their children.
“Newborns have some protection against infection thanks to antibodies passed from the mother, but this wanes in their first year, leaving infants – especially those starting childcare – more vulnerable to infections,” Dr Leo Swadling, from the UCL Institute of Infection, Immunity and Transplantation, said.
“It’s normal for children to get sick a lot because their immune systems have never seen these bugs before – but then nursery serves as a ‘boot camp’ for their immune systems, building up resilience for the years ahead.
“Vaccines are a key way to protect children from serious infections in childcare, so we encourage parents to keep their children up to date with all available vaccines."
Dr Charlotte Houldcroft, a virologist at Cambridge and the study’s corresponding author, emphasised preventing the spread of infections.
“We all have experience of our children coming home from nursery with a bug that leaves them, and often us, feeling pretty poorly – even occasionally needing hospital care,” she said.
“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.”
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