"This time of year it´s especially important to pay close attention to children 4 and under," says Marte Hernández Porras, an infectious disease specialist with the National Pediatrics Institute. "They´re the most susceptible to ear infections."

Dr. Porras is referring to acute otitis media, marked by temporary ("acute") inflammation ("-itis") of the middle ("media") ear ("ot-"). It´s extremely prevalent in young children, second only to the common cold. Experts generally agree that three quarters of all kids suffer at least one ear infection by age 4. The Health Secretariat estimates that three out of five Mexican infants less than a year old will get an ear infection.

Otitis media is not life-threatening. Doctors can treat it effectively. In fact, it will usually clear up on its own in a matter of days. True, additional problems can develop, especially in children who get frequent ear infections. But in the words of the (U.S.) National Institute of Health (NIH), "Generally, an ear infection is a simple, non-serious condition without complications."

Try telling that to a parent whose 16-month-old is feverish, irritable, not eating, vomiting and crying more than usual. Ear infections are one of the most common reasons young children are taken to a doctor. This may be especially true in Mexico, where pediatric visits are easy to arrange on short notice and relatively inexpensive.

What concerns parents about ear infections is that, unlike with simple colds, the child usually feels pain in the ear. It´s also not uncommon for him or her to experience some short-lived mild hearing loss. And the youngest victims have no way to verbalize what´s bothering them. Is it any wonder that concerned parents tend to rush them to a doctor?

The pain and the hearing loss have the same cause - fluid buildup. The infection in the middle ear - from a virus or bacteria, and sometimes first one and then the other - generates an inflammatory response. That can include pus that blocks the Eustachian tube and pushes against the drum.

In fact, a major reason young children get more ear infections is that their Eustachian tubes (pressure equalizing airways) are shorter, narrower, softer and positioned more horizontally. According to experts at Mexico City´s Medica Sur hospital, that makes them easier targets for microbes, and more prone to blockage.

Another reason is that kids 6 and under don´t yet have a fully developed immune system, so they have a harder time fighting infections. Most otitis media cases start out as a cold or other respiratory infection. That´s why this cold-weather, back-to-school time of year is the peak of the ear infection season. Otitis per se isn´t contagious, but the respiratory infection that causes it definitely is.

Ear infection symptoms aren´t always pronounced. Sometimes there simply aren´t any. So how does a parent know?

If your little girl is in bed with a cold and says her ear hurts, that´s a pretty good indication of a possible ear infection. The clearest sign in an infant is irritability or inconsolable crying beyond what you´d expect from a cold. Interestingly, the old standby that tugging at the ear is how infants try to communicate an ear infection has been thrown into doubt by recent studies showing that children with or without ear infections tug at their ears in equal numbers.

The first thing a doctor will do if you take your child in is inspect both ears with an otoscope, a sort of ear flashlight that will reveal the redness, swelling and fluid that indicate otitis. You´ll probably be asked if your child has had previous ear infections; that might affect the treatment strategy.

A five- to 10-day antibiotics course will take care of the infection, though the fluid may remain longer. However, not all cases require antibiotics. Because over-use of antibiotics is causing a worldwide weakening of their effectiveness, a conscientious physician will sometimes choose a "wait and see" approach if he or she feels the child´s immune system is capable of beating back the infection quickly.

On the other hand, children prone to frequent ear infections, or experiencing a persistent problem lasting several weeks, may need more extensive treatment, which can include an ongoing antibiotic regimen.

The other big treatment issue is pain relief. Your pediatrician will probably prescribe ear drops. But since the most intense pain usually comes during the first 24 hours, it often falls to the parents to administer the first pain relief at home. The doctor knows best on this, too, but reputable medical organization such as the NIH and the Mayo Clinic advise against aspirin for children. A better choice is the children´s version of acetaminophen (such as Tylenol) or ibuprofen (such as Advil or Motrin).

kellyg@prodigy.net.mx