When I started practicing pediatrics in the 1990s, it seemed we diagnosed a case of otitis media — middle ear infection — every few minutes. I knew the antibiotic dosages by heart for children of every weight. I knew the risk factors for ear infections: day care, exposure to parental smoking, not being breast-fed. But risk factors or no, it seemed like most small children had ear infections, every now and then.
Now in clinic, ear infections are much less common. When one of the residents gets ready to make this diagnosis, the supervising doctors sometimes get called in to verify: is the eardrum really red, bulging, not moving? (If there’s a buildup of infected fluid behind the drum it bulges out; you blow a little air into the ear, and the eardrum doesn’t move.)
In a study published in March in the journal Pediatrics, researchers tracked 367 babies during the first year of life, regularly swabbing their noses to see what viruses and bacteria had colonized them, and watching to see when — or if — they would get their first ear infections. Six percent had a first ear infection by 3 months of age; 23 percent by 6 months, and 46 percent by a year; the babies who got ear infections had twice as many colds as the babies who didn’t, reinforcing the relationship between viruses and the ear infections that can follow. They were also more likely to be colonized by bacteria that can cause infections. As in many past studies, breast-feeding lowered the risk, for both colds and ear infections.
These rates are lower than the rates found in the older studies, done in the 1980s and 1990s, in which 18 percent of babies had an episode by 3 months, 30 to 39 percent by 6 months, and 60 to 62 percent by a year. Dr. Tasnee Chonmaitree, an infectious diseases specialist and professor of pediatrics at the University of Texas Medical Branch at Galveston, and the lead author of the study, told me, “we all know we don’t see as many otitis media cases as we used to.”
What they were trying to do in this study, she said, was look carefully at the actual incidence of ear infections now, in this new environment, in which children are routinely vaccinated against Streptococcus pneumoniae, or pneumococcus, one of the types of bacteria that can cause ear infections (it can also cause more serious infections, including pneumonia and meningitis), and also against influenza, since viral infections like flu may precede bacterial ear infections. Neither vaccine is directed specifically at ear infections, but both have probably affected the incidence since my children were young.
A study published in 2014 in JAMA Pediatrics looked at the number of medical visits for otitis media made by children up to the age of 6 and found a downward trend from 2004 to 2011, with a significant drop in 2010-11. The first routine childhood pneumococcal vaccine was introduced in 2000; we changed to a vaccine effective against a wider set of bacterial serotypes in 2010.
There’s another factor that is probably contributing to the decline in ear infections, and it has to do with tightening the definition of what we call a true otitis media, and even beyond that, what we treat. There’s been a push in pediatrics to prescribe antibiotics only when really necessary. The reason my pediatrician’s behavior 20 years ago made me trust him was that I was clearly shopping for a bottle of pink medicine. It would have made me feel better to be treating something. When our doctor resisted that pressure, and instead looked carefully at the ear, I knew my child was in good hands.
It’s not always absolutely clear whether an ear infection is present. Crying can make a small child’s eardrum appear red — or at least pinkish — and having a doctor look in an ear can make a young child cry. But we’re trying hard these days not to overprescribe antibiotics, both because we worry that we’re breeding resistant bacteria, and also because of concerns about the effects that antibiotic treatment can have on the microbiome, the bacteria living on and in a healthy child.
So in clinical practice guidelines that were revised in 2004 and then again most recently in 2013, the American Academy of Pediatrics has pushed hard to tighten the diagnostic criteria for otitis media to cases where the eardrum is clearly bulging, and to suggest that older children without bad ear pain or high fevers do not have to be treated immediately with antibiotics.
“Protecting people from unnecessary antibiotics exposure helps people have a healthier microbiome, which is important for a healthy immune system,” said Dr. Carrie Byington, a professor of pediatrics at the University of Utah and chairwoman of the A.A.P. committee on infectious diseases.
So ear infections, once the very definition of “bread and butter pediatrics,” have become rarer, as a result of a combination of vaccines, breast-feeding, decreased parental smoking and increased medical vigilance about making the diagnosis and treating young children with antibiotics. It’s a happy pediatric story of the convergence of improved preventive measures, healthier environments for young babies and the medical profession’s trying to be scrupulous about limiting interventions.
“The reason goes back to the parents and the good decisions they’re making, to immunize their children, to breast-feed their children, to not smoke around their children says Dr. Carrie ByingtonIt. “Parents making these good decisions for their kids, and it’s paying off.”