Ear Infection Culprits

Always wash your child's hands and toys often. If he's exposed to fewer germs, he may not contract as many colds that invite bacteria into his ears. Attending a daycare with six or fewer children, if possible, can also reduce his risk of infection.
Relying on pacifiersStudies show that babies who stop using pacifiers after 6 months of age have one-third fewer ear infections than kids who hang onto them. Sucking may change the pressure balance between the air and nasal passages, making it more difficult for fluid to drain properly.
BottlefeedingInfants who breastfeed are less prone to ear infections because a mother's milk passes along immunity that protects the middle ear. If you bottlefeed, hold your baby in an upright, seated position to prevent formula from entering the middle ear and establishing a breeding ground for bacteria. And don't give your baby a bottle while she's lying in bed.
Inhaling secondhand smokeThis irritates and swells the passage connecting the middle ear and nose, making it easier for infections to take hold.
Skipping the pneumococcal vaccineIt fights diseases like pneumonia and bacterial meningitis-and it reduces cases of middle ear infections in infants and children.
Parents.com