This means their immune systems may not receive sufficient early exposure to the germs needed to develop properly. (nhs.uk)
The health of all classroom participants is important to us, so we take measures to ensure the cleanliness of our classroom and limit exposure to germs. (musictogethersusquehanna.yourvirtuoso.com)
Exposure to germs in childhood is thought to help strengthen the immune system and protect children from developing allergies and asthma, but the pathways by which this occurs have been unclear. (scientificamerican.com)