How Can Viral Infection In Nose Trigger Bacterial Infection In Ear?

Middle Ear Infection which is medically referred to as acute otitis media is an extremely common condition seen in children. In fact, it is estimated that about 85% of children under the age of 3 get affected by middle ear infections. While these infections tend to have a bacterial cause, latest studies have shown that these infections can also be triggered by viral infection in the nose. The most common virus that can infect both the nose and the ear is the flu virus.[1,2,3]

The study states that the flu virus inflames the nasal tissue and increased the number of bacteria and their tendency to travel through the eustachian tube and cause an infection in the middle ear. This study is published and available in the American Society of Microbiology.[1,2,3] This article gives further information on how viral infection in the nose triggers bacterial infection in the ear.

How Can Viral Infection In Nose Trigger Bacterial Infection In Ear?

The study was conducted by a group of researchers from the Wake Forest Baptist Medical Center in Winston-Salem, NC. The findings as stated are available in American Society of Microbiology in the journal Infection and Immunity. The lead researcher of this study states that bacteria are naturally present in the body especially in the stomach and throat, but they are also present in the nose. These bacteria generally do not cause any problems. However, in some instances these bacteria can travel to the ears and cause middle ear infection.[1,2,3]

The researchers conducted an animal study. The study showed that when the nose was infected with a flu virus and bacterium that causes ear infections, it resulted in inflammation of the nasal tissues. As a result of this inflammation, the number of bacteria increased and with it also increased the likelihood of them traveling through the eustachian tube into the middle ear resulting in an infection. The bacterium that was investigated in the study was Streptococcus pneumoniae. This bacterium is known to be naturally present in the nose of children in the dormant and active phases.[1,2,3]

In the dormant phase, the bacterium is completely harmless but in the active stage it tends to cause infection, especially in the ears. The study further indicated that the presence of flu virus resulted in infection by this bacterium even in its dormant stage. The researchers found out that the presence of the flu virus accelerated the growth of S. pneumoniae and infect the middle ear.[1,2,3]

Researchers believe that the reason behind it is that the viral infection in the nose evoked an immune response to this bacterium resulting in the bacterium infecting the ears even in its dormant or benign state. Middle ear infection is quite a common occurrence in United States which is quite heavy on the pocket.[1,2,3]

The American Academy of Otolaryngology states that 3 in 5 children develop their first middle ear infection by the time they reach one year of age. This figure increases to 4 out of 5 children by the time they are 3 and almost every child has had it at least once by age 5. It is estimated that approximately 25 million hospital visits every year for children are due to middle ear infections. The bacterium mainly responsible for these infections is the Streptococcus pneumoniae.[3]

In conclusion, viral infection in the nose is indeed responsible for middle ear bacterial infections. This has been proven in a study conducted on animal models. The primary virus responsible for it is the flu virus. It accelerates the growth of the naturally present streptococcus pneumoniae bacterium in the nose and also increases their propensity to travel through the eustachian tube in the middle ear and cause infection.[1,2,3]

This was seen in both the states that the bacterium has namely, benign and active states. Why does this happen was explained in that the flu virus evokes an immune response to the bacterium which accelerates its growth and causes middle ear infections. It is estimated that approximately 25 million hospital visits every year in the United States for children are due to middle ear infections.[1,2,3]

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