Parents of young children are often all too familiar with ear infections. The pain, the fever, the tear-filled nights almost seem like a rite of passage for children in their first two years of life.
But ear infections are not an inevitability of babyhood. A new study suggests that the number of ear infections in infants has decreased over the past couple decades. The study points to several factors, including vaccines and breast-feeding, that have probably spared babies the agony of ear infections.
Researchers followed more than 300 babies from the time they were less than a month old until 12 months. They diagnosed cases of ear infection as well as the common cold and looked at a range of factors that could influence a child’s risk of ear infection, including bacteria and viruses present in their nose and throat, exposure to cigarette smoke and whether they were breast-fed.
During the study period, 46% of the children developed an ear infection by the time they were 1. That rate is an improvement compared with what studies in the 1980s and 1990s found, in which about 60% of children had had an ear infection in their first year of life.
“For parents, it’s good news that the most common disease in infants and young children has come down,” said Dr. Tasnee Chonmaitree, professor of pediatrics at the University of Texas Medical Branch. Chonmaitree is lead author of the study, which was published Monday in Pediatrics.
Although the current study only involved babies around Galveston, Texas, and the older research reporting higher numbers of ear infection was carried out in other parts of the United States, Chonmaitree thinks these studies probably capture the rates of ear infection around the whole country. The lower rates that she and her colleagues found in Texas probably indicate that babies and parents everywhere in the United States have been getting a break from ear infections in recent decades.
Most common reason for pediatrician visits
Ear infections lead to more pediatrician visits than any other medical problem, and are the most common reason that children take antibiotics and undergo surgery.
Surgery is typically recommended for children who suffer multiple ear infections and involves placing a small tube through the eardrum to ventilate the middle ear and reduce the risk of future infections.
The peak time that children develop ear infections is between 6 and 24 months of age. Although the current study only looked at children up to a year of age, Chonmaitree thinks that ear infection rates have probably also come down in toddlers.
“Medical progress in the past few decades has brought down the incidence of ear infection,” Chonmaitree said.
Progress has probably come in several forms, including higher rates of breast-feeding, reduced exposure to cigarette smoke and the introduction of a pneumococcal vaccine in 2000. PCV13, or Prevnar 13, protects against 13 types of pneumococcal bacteria and is recommended for all children starting at two months.
The study found that the presence of Streptococcus pneumoniae in the nose and throat was associated with 165 times greater risk of babies having an ear infection. A number of viruses were also linked to higher ear infection rates, including the flu and rhinovirus, which is the most common cause of the common cold.
The study also found, as many studies have before that, that ear infections often manifest after a bout with the common cold. Nearly every ear infection in the current study occurred in a baby that had just had the common cold, typically several days earlier. Out of 859 cases of common cold, 21% were followed by an ear infection.
“The common cold starts the process of infection in the nose or area behind the nose, it causes an obstruction, and changes in middle ear pressure, and that allows both viruses and bacteria into the middle ear,” Chonmaitree said.
Breast-feeding, smoking and vaccines
Another factor that could protect babies from ear infections is breast-feeding. The study found that babies that were exclusively breast-fed for at least six months were 63% less likely to have an ear infection. The benefit of breast-feeding could be because maternal antibodies in breast milk help prevent infections in babies, Chonmaitree said.
On the other hand, the study did not implicate cigarette smoke in ear infection risk, but that is probably because there were too few babies in the study that were exposed to cigarette smoke to detect an increase in risk, Chonmaitree said.
“We believe that the impressive reduction in smoking in the last few decades had an impact” on reducing ear infection incidence, she said.
The study is “quite suggestive that the incidence of ear infection has come down in last few decades,” said Dr. Mark R. Schleiss, director of pediatric infectious diseases and immunology at University of Minnesota, who was not involved in the study. “Intuitively it makes sense with the vaccines that we have that have improved care,” he added.
“I would say to parents (that) the things that you can do, and this study confirms it, to decrease the risk of ear infection in your child are simple and not terribly expensive and they have a big impact,” Schleiss said. These include making sure your child receives Prevnar 13, the pneumococcal vaccine, and the flu vaccine when they are recommended, trying to breast-feed exclusively for the first six months and avoiding cigarette smoke.
Chonmaitree adds to that list that parents should try to avoid exposing their baby to people who have the cold. And for babies prone to ear infections, parents should try to use smaller day care groups or home day care, as settings with many children increase transmission of the common cold.
If parents think their child has an ear infection, they should take them to a physician or health care provider, Schleiss said. Ear infections can sometimes lead to serious complications such as structural damage in the ear or infection in the skull.
“These are all rare complications; the problem is there is just no way to predict which child will get complications,” Schleiss said.