What's normal: One episode a year.
What's not: Drooling or great difficulty swallowing.
Why your child may be vulnerable: As many as one in 10 kids with strep -- a bacterial infection of the tonsils caused by highly contagious Streptococcus pyogenes bugs -- don't respond to the first course of antibiotics prescribed by a doctor.
So even though these kids have been treated, the infection never gets knocked out. Some children need longer treatment to get rid of the strep bacteria; others, a different antibiotic.
Sometimes kids come in close contact with a carrier who has no symptoms but can pass the infection along. And if your child gets her first infection during peak strep season (spring and fall), she's more likely to become reinfected, because bacteria thrive during those months, causing infections to be three times more prevalent than in winter or summer.
Parents may contribute to repeat infections, too. Strep symptoms heal quickly with treatment, leading many parents to stop giving medication early: One study found that while 80 percent of families claimed they'd administered every dose of antibiotics, 50 percent had stopped after just three days. Full treatment is necessary to wipe out all of the strep bacteria.
Doctors are swift to treat strep throat in order to prevent rare yet serious complications such as heart-damaging rheumatic fever. But the most accurate test -- a throat culture -- takes two days to yield results. A rapid antigen test offers results in minutes but can fail to detect strep about 20 percent of the time. For these reasons, doctors may overdiagnose and overprescribe antibiotics to be on the safe side. Bottom line? Your child may not have strep at all.
Advice for parents: Ask for a 10-day course of antibiotics, and make sure your child takes all of it. "Studies have shown that a seven-day course of penicillin is much less likely to eradicate the strep germ than is a 10-day course," says Richard J. Schmidt, MD, a fellow in pediatric otolaryngology at the Nemours/Alfred I. duPont Hospital for Children, in Wilmington, Delaware.
When strep keeps coming back with a vengeance, some doctors are suggesting an old standby: tonsillectomy. Repeat infections can create pockets of hard-to-kill bacteria on the tonsils.