"Mommy, my ear hurts!"  Countless parents have awakened in the middle of the night to that plaintive cry. With nearly 70 percent of youngsters developing otitis media by age two, middle ear infections rank second only to the common cold as the most frequent illness among American children. 

  Early detection and treatment of middle ear infections are essential to prevent serious consequences. Untreated middle ear infections could lead to mastoiditis (swelling behind the ear), brain abscesses, meningitis or permanent hearing loss.

  Usually, otitis media occurs when bacteria or a virus invade the middle ear as a result of colds, allergies or infected adenoids. This results in a build-up of fluid and inflammation. In cases of otitis media with effusion, there is an accumulation of fluid but no infection. This also needs to be treated since it can lead to hearing loss. 

  Children are much more susceptible to middle ear infections than adults. Their immune systems aren't fully developed, and their eustachian tubes, which extend from the middle ear to the nose, are shorter and horizontal; they don't always drain fluid from the ear efficiently. However, most children outgrow their susceptibility by age five.

Most children will experience some, but not necessarily all, of these symptoms:

• Acute ear pain. Babies may be fussy, cry and rub or pull at their ears.
• Discharge of blood or pus from the ear.
• Fever.
• General irritability.
• Nausea and vomiting.
• Temporary hearing loss. 

  If you suspect an ear infection, have your child examined by a doctor immediately. Using an instrument called an otoscope, the doctor can inspect the condition of the eardrum. If infection is present, treatment usually involves penicillin or other antibiotics given for 10 or more days. It is important to administer the medicine exactly as directed by your physician, and to complete the full course even if your child feels better. 

  Your doctor may also suggest giving your child antihistamines or a decongestant (especially for children prone to allergies) and/or a pain reliever, such as acetaminophen. (Do not give aspirin to children with a viral infection; its use has been linked to Reye's syndrome, a rare but potentially fatal disease.) It's important to schedule a follow-up exam after the course of antibiotics is finished, especially for babies and small children who aren't able to tell you whether their ears still hurt or if they can hear properly.

  If antibiotic treatment fails, hearing loss has occurred or the ear infections keep recurring (common in children with allergies), your doctor may recommend a surgical procedure called myringotomy. This procedure involves making a small incision in the eardrum so the physician can suction out the fluid. He or she may then insert small plastic tubes in the ear, which can help keep fluid from accumulating. The surgery takes about 15 to 30 minutes under general anesthesia and is usually performed on an outpatient basis.