Middle Ear Infections May Be Triggered by Viral Issues in the Nose

Statistics show that many middle ear infections primarily hit children under the age of 3. Though not typically serious, researchers are still learning about just what causes this health issue.

Recent findings published in the journal Infection and Immunity show how these infections may be triggered by a viral infection that's already present in the nose, instead of solely based on a bacterial infection alone. Furthermore, more than 85 percent of children are predicted to deal with this kind of issue during the younger years.

"Every individual has bacteria in the nose that most of the time doesn't cause problems," said lead study author W. Edward Swords, Ph.D., professor of microbiology and immunology at Wake Forest Baptist, in a news release. "However, under certain conditions those bacteria can migrate to the middle ear and cause an ear infection, and now we have a better understanding of how and why that happens."

By simultaneously infecting the nose with a flu virus and a bacterium that is one of the leading causes of ear infections in children, researchers have discovered that the flu virus inflames nasal tissue and can significantly increase both the number of bacteria, as well as its propensity to travel to other areas through the Eustachian tube and infect the middle ear in this way.

For their research, the study authors used a bacterium found in animals but that also commonly exists in the noses of children in two phases--one relatively invasive while the other relatively benign.

"These findings suggest that a flu infection modifies the response of the immune system to this particular bacterium, enabling even the type that has previously been considered benign to infect the middle ear," Swords concluded.