Tonsils and adenoids are near the entrance to the breathing passages where they can catch incoming germs, which cause infections. They sample bacteria and viruses and can become infected themselves. Scientists believe they work as part of the body’s immune system by filtering out germs that attempt to invade the body. They also help to develop antibodies to germs and viruses. This happens primarily within the first few years of life, becoming less important as we grow older. Children who must have their tonsils and adenoids removed suffer no loss in their resistance.