Otitis media is an inflammation that occurs in the middle ear. Middle ear space contains fluid that could be easily infected and the infected middle ear is called otitis media with effusion. The cause of the chronic OME (otitis media with effusion) for most of the allergic rhinitis patients is mainly due to the IgE-mediated allergies. IgE-mediated allergy is the allergy that happens when IgE antibody (one type of the white blood cell) binds with the mast cell. IgE antibody is being produced by the plasma cell when foreign particular from outside of the body entering into the blood through nasal mucosal surface. Once the IgE antibody binds with the mast cell around the nose, histamine is secreted from this cell and it is the main chemical that causes itching and hypersensitive of the nose. According to the publication by a group of scentists, 50% of the children who had chronic OME also had nasal allergy [Acta Otolaryngol (Stockh) 1988;458(suppl):41-7]. Effects of the seasonal allergic rhinitis to the Eustachian tube function and middle ear pressure had been studied by a few groups of medical scientists. According to one of the studies, Eustachian tube of the pollen allergic patients become obstructed increases from 15% to 60% from the starting to the maximum of the pollen exposure. [Ann Allergy 1990;65:206-10]. In one of the studies, ragweed pollen , which is a seasonal pollen, was let it exposed to a group of people. What had been discovered is that it will cause immune reactions in the Eustachian tube and nose [Am J Rhinol 1988;2:155-61.].Apart from this study, the other study reported that house-dust mite, which was a perennial allergen, also caused Eustachian tube obstruction [ ArchOtolaryngol Head Neck Surg 1986;112:840-]. In the same study, they found out that 55% of the adults, who had nasal allergy, experienced the development of the Eustachian tube dysfunction when this group of adult was exposed to house-dust mite. In the following study, new thing that had been found out was Eustachian tube obstruction happened more frequently for the patients who had allergic rhinitis. [J. Allergy Clin Immunol 1987;79:27-31]. In allergen provocation studies, scientist found out that nasal obstruction usually occurred before the development of the Eustachian tube obstruction. In allergen provocation study, individuals who took part in this study were exposed to allergen to provoke their nasal allergy symptom. In this study, researchers also discovered that various of inflammatory mediators such as histamine have been detected in middle ear effusions of the children who had OME [Arch Otolaryngol Head Neck Surg 1988;114:1131-3]. If Eustachian tube obstruction that was caused by perennial exposure to allergen such as house-dust mite was left it untreated for quite a sometime, it could form middle ear disease, especially, when priming phenomenon occurs in the Eustachian tube. Priming phenomenon happens when mucosa in the organ responds to lower doses of allergen with repeated exposure. Allergic rhinitis could have priming phenomenon too when the mucosa in the nasal passage responds to low amount of allergen that has been inhaled through the nostril. For the Eustachian tube obstruction that was caused by seasonal exposure to allergen such as ragweed pollen, its physiologic hyperresponsiveness could extend beyond the ragweed season.
Studies show that half of the newly occurrence otitis media are diagnosed immediately after patient had been infected by viral URTI (virus that causes flu and common cold). By using traditional standard culture techniques, it is quite rare that viruses could be isolated from the middle ear effusions in the patient with otitis media. However, with the newly developed PCR-based molecular analysis, viruses in the middle ear effusions could be detected and discovered that 53% of the middle ear effusions are positive for viruses [J Infect Dis 1995;172:1348-51]. An experimental, which was carried out by infecting real human with rhinovirus-39, had been carried out in Children's Hospital of Pittsburgh to study the effect of this virus to the middle ear pressure and Eustachian tube. Result of this experiment showed a substantial increase of Eustachian tube dysfunction and also abnormal middle ear in approximately 30% of the people who had been infected in this study. However, all these people who had been infected by this virus had less possibility to develop an otitis media disease. In another study, where influenza A virus was intranasally inoculated to a group of peoples, 59% of the inoculated people experienced the development of middle ear under pressure and only 25% of these people developed otitis media [J Infect Dis 1995;172:1348-51]. In this study, one of the inoculated people developed middle ear under pressure followed by purulent otitis media. This patient middle ear effusion was taken for PCR analysis and it showed positive result for both influenza A and Streptococcus Pneumoniae. Streptococcus Pneumoniae is some kind of spherical, Gram-positive, alpha-hemolytic bacterium and it is a member of the genus Streptococcus. In this group of inoculated people, 80% of them who had infected by this virus experienced the development of Eustachian tube dysfunction and 80% of them had middle ear under pressure [Ann Otol Rhinol Laryngol 1994;103:59-69]. With this group of infected people, five of them had developed OME on the 4th day after the viral exposure. One of the patients had dizziness and vertigo symptoms, which is mainly due to the inner ear malfunction. All these studies support the causes of otitis media by URTIs virus and causes of otitis media starting from the development of Eustachian tube obstruction and abnormal middle ear pressure. In the recent publication about the study of a group of children with acute otitis media, micro-organisms in the fluids of the middle ears of the children were isolated by the investigator of this study. They found out that 65% of the fluid samples that had been collected contained both bacteria and viruses. These results show that virus infection in the middle ear creates an environmental that is suitable for the breeding of bacteria. [N Engl J Med 1999;340:260-4].

Based on the information that had been collected from a few recent publications of the studies of the relationships of the allergic rhinitis to the OME (otitis media with effusion), we could conclude that allergic rhinitis or common cold/flu will cause Eustachian tube obstruction and middle ear pressure. When the situation becomes uncontrollable, otitis media with effusion will develop and this may could permanent hearing impairment. Therefore, allergic rhinitis and common cold/flu should be treated immediately without any delay. This is because these common illnesses may become serious and develop to chronic sinusitis disease and otitis media with effusions, which is quite difficult to cure.