Flu Virus in Nose can Cause Ear Infections: Study

Virus found in infants' noses can cause severe infection in the middle ear, warns a study.

Symptoms of viral infections like common cold and cough allow bacteria to thrive and multiply in the nasal cavity that eventually progresses into infections in the middle ear. The microorganisms use the Eustachian tube that connects the ear and nose as a pathway to spread infections. These conditions are common in 85 percent of children aged less than three.

Experts at the Wake Forest Baptists Medical Center used an animal model to study the mechanism that triggers infection in the ear canal. The laboratory animals were exposed to streptococcus pneumonia, a bacteria found in young children's noses. The animals' ear were also affected with the bacterium simultaneously.

It was observed that the virus in the nasal cavity initiated infectious reactions in the nose-to- ear channel leading to massive infections regardless of its state inside the nose. But, these findings do not indicate that everyone with nose virus are likely to experience ear infections.

"However, under certain conditions these 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," said Edward Swords, study author and professor of microbiology and immunology from the Wake Forest Baptist Medical Center, reports the Business Standard.

"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 adds.

More information is available online in the journal Infection and Immunity.