L’ESSENTIEL
- After starting daycare, a one-year-old child will experience, on average, 12 to 15 respiratory infections, two cases of gastroenteritis, and one or two skin rashes during their first year.
- This high prevalence of infections in young children is normal, linked to immature infant immunity and the dynamics of pathogen transmission.
- The situation improves over time, as the frequency of respiratory infections, which is almost monthly, decreases year after year, which is not the case for children who have never attended daycare.
“Childcare outside the home, a common practice in high-income countries, is associated with an increased incidence of infectious diseases, not only for the child but also for their parents and other household members,” scientists from the universities of Cambridge, Cornell, UCL, and North Middlesex University Hospital have indicated. In novel research published in the journal Clinical Microbiology Reviews, the researchers explored this phenomenon from various angles, combining the age of first infection, maternal antibody dynamics, sero-epidemiology (the prevalence of exposure to a microorganism within a population), cohort studies, and epidemic reports. Their goal? To understand the link between the immune system of children starting childcare and the pathogenic environment to which they are exposed.
Daycares: Children contract an average of 12 to 15 respiratory infections
After gathering and analyzing data from epidemiology, immunology, and vaccination, the team found that a one-year-old child entering daycare will contract an average of 12 to 15 respiratory infections, two cases of gastroenteritis, and one or two skin rashes during their first year alone. “Our personal experience, that of parents observing a high incidence of infections after their child starts daycare, is corroborated by the data,” said Lucy van Dorp, co-author of the study and researcher in infectious disease genomics at the UCL Genetics Institute.
According to the results, young children are particularly susceptible to illness, primarily due to the immaturity of their immune systems and the inherent transmissibility of childhood pathogens, rather than poor hygiene or inadequate childcare practices in daycare settings. “Newborns benefit from some protection against infections through antibodies passed on by their mother, but this protection decreases during their first year, making infants (especially those starting childcare) more vulnerable to infections,” explained Leo Swadling, who participated in the research.
Young children immunized after daycare are less often sick during their early school years
The authors observed that toddlers attending daycare acquire sick more often than those staying home until starting school. However, this trend reverses once children are enrolled in school. Children who had not attended early childhood education facilities get sick more often, and those who attended daycare were less likely to be infected with a virus and had fewer symptoms during their early school years. “Early exposure to infections in a collective setting seems to confer some protection during the first years of school, probably through the acquisition of immunity against common infections. (…) Daycare then plays an essential role in the development of their immune system, strengthening their resistance for the years to come.”
In their conclusions, the researchers emphasize the importance of following recommendations and keeping children home when they are sick, “and possibly one or two days after their recovery, depending on the type of infection,” to limit the spread of viruses. They also remind readers that vaccination remains the best way to protect against childhood illnesses. This research highlights the complex interplay between early childhood exposure to pathogens and the development of a robust immune system, offering valuable insights for parents and public health officials.
