Infections can be transmitted from person to person through physical contact or just from being in the same room. When children from different families attend child care, infections spread easily. Children's normal affectionate beheviour is part of the reason. Toy sharing, hugging and kissing are all quick ways to pass germs, but shouldn't be discouraged. What should be encouraged is better hygiene, especially handwashing.
Respiratory infections are the most common childhood illnesses.
They're in saliva and nose secretions. Respiratory germs float through the air and are inhaled or settle in the eyes, nose or mouth. Colds and flu are examples of infections caused by germs that spread this way. Ear infections are also caused by repiratory tract germs. Strep throat germs are spread when you sneeze or cough.