Ear infection

Related Terms

Acute viral nasopharyngitis, asdenoid, allergy, auditory, aural, chronic suppurative otitis media, common cold, eustachian tube, Fahrenheit, flu, influenza, labyrinthitis, larynx, mastoiditis, mucous membrane, mucus, myringotomy, myringoplasty, externa, otitis media, otitis, otitis interna, otorrhea, pneumatic otoscope, pneumonia, reflectometry, respiratory syncytial viruses (RSV), rhinoviruses, sinus, sinusitis, swimmer's ear, symptomatic, tonsil, trachea, tympanocentesis, tympanometry, tympanoplasty, upper respiratory infection (URI), vertigo, viral infection, virus.

Background

Otitis media refers to inflammation of the middle ear. When infection occurs, the condition is called acute otitis media, or ear infection. Acute otitis media occurs when a cold, allergy, or upper respiratory infection (including the nose, sinuses, larynx or voice box, and throat) and the presence of bacteria or viruses lead to the accumulation of pus, inflammation, and mucus behind the eardrum, blocking the eustachian tube (tube leading from the ear to the throat). Earache is painful due to swelling, but usually does not require treatment. More fluid may collect and push against the eardrum, causing pain and sometimes a temporary or, in severe cases, a permanent loss of hearing. Fever generally lasts about one to two days; pain and crying may last for three to four hours. After that, most children have some pain on and off for up to four days, although young children may have pain that comes and goes for up to nine days. Adults experience similar symptoms.
Next to the common cold, ear infections are the most commonly diagnosed childhood illness in the United States. More than three out of four children have had at least one ear infection by the time they reach three years of age. Adults can get the condition also, but it is much less common.
A child's eustachian tubes (tubes connecting the ears to the throat) are narrower and shorter than those of an adult. This makes it easier for fluid to get trapped in the middle ear when the eustachian tubes dysfunction or become blocked during a cold. This provides a perfect breeding ground for infection to develop.
Treating children with antibiotics may shorten these symptoms by about one day, according to a study of 240 children ages six months to two years. However, about 80% of the time the immune system can fend off infection and heal the ear infection without the use of antibiotics. In severe cases, too much fluid can increase pressure on the eardrum until it ruptures, allowing the fluid to drain. When this happens, fever and pain usually go away and the infection clears. The eardrum usually heals on its own, often in just a couple of weeks. However, if the eardrum does not heal, a doctor may touch the edges of the eardrum with epidermal growth factor to stimulate growth and then place a thin paper patch on the eardrum.

Signs and symptoms

Ear infections (otitis media) are often difficult to detect in kids because most children affected by this disorder do not yet have sufficient speech and language skills to tell someone what is bothering them. Common signs to look for include unusual irritability, difficulty sleeping, tugging or pulling at one or both ears, earache, fever, fluid draining from the ear, loss of balance, and unresponsiveness to quiet sounds or other signs of hearing difficulty such as sitting too close to the television or being inattentive. Fluid buildup in the middle ear also blocks sound, which can lead to temporary hearing difficulties. An older child or adult may complain verbally of an earache (ear pain).
If the pressure from the fluid buildup is high enough, it can cause the eardrum to rupture, resulting in drainage of fluid from the ear, which may include blood and thick, yellow pus. This releases the pressure behind the eardrum, usually bringing on relief from the pain.
Otitis media with effusion often has no symptoms at all. In some individuals, the fluid that is in the middle ear may create a sensation of ear fullness or "popping." As with acute otitis media, the fluid behind the eardrum can block sound, so mild temporary hearing loss can happen, although it may not be obvious.
Ear infections are also frequently associated with upper respiratory tract infections (such as colds), so signs and symptoms such as a runny or stuffy nose or a cough may be present. An ear infection is not contagious (able to be spread), but the cold that may have caused the infection can be. Symptoms of a middle ear infection (otitis media) often start two to seven days after a cold or other upper respiratory infection.
Duration: Acute ear infections usually clear up within one or two weeks. Sometimes, ear infections last longer and become chronic (long term). After an infection, fluid may stay in the middle ear. This may lead to more infections and hearing loss.
The signs and symptoms of acute otitis media may range from very mild to severe.

Diagnosis

Middle ear infections are usually diagnosed using a health history, a physical exam, and an ear exam.
Pneumatic otoscope: If a middle ear infection is suspected, a healthcare provider will use a pneumatic otoscope (an instrument for looking into the ear that puffs air) to look at the eardrum for signs of redness or bulging. In the case of fluid buildup without infection (otitis media with effusion), the eardrum can look like it is bulging or sucking in. In both cases, the eardrum doesn't move freely when the pneumatic otoscope pushes air into the ear.
Tympanometry: Tympanometry tests the movement of the eardrum. The tip of a hand-held tool is placed just inside the ear. It changes the air pressure inside the ear. Then, the tool measures how the eardrum responds. If the air pressure is not appropriate, then a ruptured ear drum may be present.
Hearing tests: A hearing test is recommended for children who have fluid in one or both ears (otitis media with effusion) for more than three months. Hearing tests are done sooner if hearing loss is suspected.
Tympanocentesis: Tympanocentesis is performed when fluid stays behind the eardrum (chronic otitis media with effusion) or infection continues even with antibiotics. Tympanocentesis can remove the fluid. The doctor uses a needle to pierce the eardrum and suck out the fluid. A sample is usually tested for bacterial or viral growth. These tests reveal what kind of bacteria or virus is causing the infection and which medication is best for treatment. The child may need analgesia or sedation before this procedure due to this being an uncomfortable procedure. Analgesia can be used when indicated with acetaminophen, with codeine (Tylenol #3?), or with diazepam (Valium?) for sedation. Side effects include drowsiness and sedation after the procedure is completed.
Reflectometry: Reflectometry is used if the ear exam with a pneumatic otoscope does not indicate that fluid is behind the eardrum. The tip of a small handheld instrument is placed in the ear canal and sends off a sound. How the eardrum reacts to the sound tells the doctor if fluid is present.
Blood tests, including white blood cell counts, can be used to determine if the immune system is functioning properly.

Complications

Many ear infections clear on their own with no complications. However, long-lasting or recurrent infections can be detrimental, leading to hearing loss.
Short-term hearing loss: Fluid buildup can temporarily affect hearing. The hearing loss occurs because it is more difficult for the eardrum and the bones in the middle ear to send sound vibrations through fluid. The average hearing loss is 25 decibels, approximately the same effects as using ear plugs.
Long-term hearing loss: Usually the fluid disappears on its own in a few weeks. But sometimes it remains in the middle ear for months, which can damage the eardrum and bones in the middle ear. Persistent middle ear fluid was once thought to contribute to speech or developmental delays, but researchers now say this is not true.
Ruptured eardrum: During ear infections, fluid and pus may press against the eardrum and be very painful. Sometimes the pressure ruptures the eardrum. If this occurs, a discharge (release) of pus and blood from the individual's ear may be seen. The rupture actually relieves the pain, and in most cases the eardrum heals on its own. If the eardrum ruptures repeatedly and does not heal, surgical repair may be needed.
Mastoiditis: Untreated ear infections may lead to a type of sinusitis (sinus inflammation) known as mastoiditis, which affects the mastoid bone of the skull in the temple area. Very rarely, infections can move from the ear to other parts of the head, including the brain. Death can occur in severe cases.
Experts recommend contacting a healthcare provider immediately if the individual has a severe injury to the ear, has sudden hearing loss, severe pain, drainage from the ear, or dizziness, seems to be very sick with symptoms such as a high fever (over 102 degrees Fahrenheit), and has redness, swelling, or pain behind or around the ear. A doctor should be seen if a person with an ear tube develops an earache or has drainage from the ear.

Treatment

Ear infections can be treated several ways. The best treatment option for a patient depends upon a variety of factors, including the individual's age, medical history, level of pain, and the type of ear infection.
The American Academy of Pediatrics (AAP) and the American Academy of Family Physicians (AAFP) recommend a wait-and-see approach for the first 72 hours for children with ear infections who are older than age six months, are otherwise healthy, have mild signs and symptoms, and a diagnosis of infection has not been made. Most ear infections clear without treatment in just a few days, and antibiotics will not help an infection caused by a virus. About 80% of children with acute otitis media recover without antibiotics, according to the AAP and AAFP.
Pain medicines: If a patient (adult or child) is uncomfortable, the doctor may recommend an over-the-counter (OTC) pain reliever such as acetaminophen (Tylenol?, Tempra?) or ibuprofen (Advil?, Motrin?). It is important to read the labels closely on these medications and give the proper dosage, especially in children and infants. Measuring devices (such as spoons) may be purchased at the pharmacy. Also, it is not recommended by healthcare professionals to give aspirin to anyone younger than 18 because its use has been linked to Reye's syndrome, a serious illness that needs emergency treatment.
Otic preparations: Otic (ear) preparations, also called ear drops, are commonly used in both adults and children to relieve pain and inflammation. If the individual does not have drainage from the ear or ear tubes, prescription eardrops containing a local anesthetic (deadening agents) and anti-inflammatory drugs may be an option. Ear drops containing neomycin and polymixin B (both antibiotics) are available for infections. They are made as solutions and suspensions (used only if there is a rupture). Brand names include AK-Spore HC?, Cortisporin?, and Otocort?. Ear drops that contain anesthetics include benzocaine (Americaine Otic? and Otocain?) and a combination of antipyrine (an anti-inflammatory) and benzocaine (Auralgan?, Auroto?, Otocalm?).
It is best to warm the ear drops to body temperature (37 ?C or 98.6 ?F), but no higher, by holding the bottle in the hand for a few minutes and gently rolling the bottle before using the medicine. This helps to lessen the pain in the ear. The individual must lie down or tilt the head so that the infected ear faces up. The earlobe is gently pulled up and back for adults (down and back for children) to straighten the ear canal. The medicine is then dropped into the ear canal as directed, keeping the ear facing up for about five minutes to allow the medicine to coat the ear canal. For young children and other patients who cannot stay still for five minutes, keeping the ear facing up for at least one or two minutes may be best. Watching television can also help keep children from moving around. Cotton may be placed in the ear canal to keep the medicine from running out. Keep the medicine as germ-free as possible - do not touch the dropper to any surface (including the ear) and keep the container tightly closed. To help clear up the infection completely, keep using this medicine for the full time of treatment, even if the symptoms have disappeared, and do not miss doses.
Antibiotic therapy: If the individual is younger than age six months or has two or more ear infections within 30 days or chronic otitis media with effusion, the doctor may recommend an antibiotic. The American Association of Pediatrics (AAP) and the American Association of Family Practitioners (AAFP) recommend the use of high doses and short courses of amoxicillin (Amoxil?, Trimox?) or amoxicillin combined with clavulanate potassium (Augmentin?) in individuals (including children) with otitis media. Erythromycin antibiotics (Eryped? or Erytab?) may also be used. Amoxicillin and erythromycin capsules, tablets, and flavored liquid preparations are available. If the medication is working, the individual should start feeling better in a few days. If the adult or child still has symptoms (fever and earache) longer than 48 hours after starting an antibiotic, a doctor may want to change antibiotics. Research shows that ear infections are often successfully treated with a five day course of antibiotics. But if the child is younger than two, he or she may need at least seven to ten days of antibiotics. The antibiotic must be given for the full length of the prescription. Stopping medication too soon could allow the infection to come back. Remember, antibiotics will not help an infection caused by a virus. Side effects of antibiotic use include nausea, vomiting, stomach cramps, diarrhea, and allergic reactions. Ciprofloxacin (Cipro Otic?) ear (otic) drops or ofloxacin (Floxin Otic?) can also be used in the ear.
Drainage tubes: If fluid in the individual's ear is affecting his or her hearing or recurrent ear infections don't respond to antibiotics, surgery may be needed. The most common surgery for ear infections is a myringotomy. During this procedure, which requires general anesthesia, a surgeon inserts a small drainage tube through the eardrum. This helps drain the fluid and equalize the pressure between the middle ear and outer ear. Hearing should improve immediately. If the ear infections continue after age four, the surgeon may recommend removing the adenoids (tonsils).
Ruptured eardrums: If the individual has a ruptured eardrum, keep water from getting into the ear canal until a healthcare provider says the hole in the eardrum has healed. Low-cost earplugs made of moldable silicone can help when swimming or bathing. Experts recommend taking a shower, bath, or swimming, but do not soak the head under water. If a ruptured eardrum hasn't healed in three to six months, the individual may need surgery to close the hole in the eardrum (myringoplasty or tympanoplasty). This surgery is rarely done because the eardrum usually heals on its own within a few weeks. If a child has had many ear infections, surgery may be delayed until the child is seven to nine years old to allow time for eustachian tube (connecting the ear to the throat) function to improve. At this point, the child may no longer need surgery.

Integrative therapies

Unclear or conflicting scientific evidence:
Belladonna: Belladonna (Atropa belladonna) is an herb that has been used for centuries for a variety of indications. Belladonna is used as a homeopathic drug regulated by the U.S. Food and Drug Administration (FDA). Homeopathic drugs use very dilute amounts of a plant or mineral, such as belladonna. Reports of side effects associated with homeopathic medicines are lacking in the available literature. In clinical study, individuals taking a 30X dilution of belladonna were reported to experience significantly fewer recurrences of otitis media (29.3 vs. 43.5%), shorter treatment duration, and a shorter duration of symptoms than subjects treated with antibiotics.
Avoid if allergic to belladonna or plants of the Solanaceae(nightshade) family (such as bell peppers, potatoes, or eggplants). Avoid with a history of heart disease, high blood pressure, heart attack, abnormal heartbeat, congestive heart failure, stomach ulcer, constipation, stomach acid reflux, hiatal hernia, gastrointestinal disease, ileostomy, colostomy, fever, bowel obstruction, benign prostatic hypertrophy (enlarged prostate), urinary retention, glaucoma (narrow angle), psychotic illness, Sj?gren's syndrome, dry mouth, neuromuscular disorders (such as myasthenia gravis), or Down's syndrome. Avoid if pregnant or breastfeeding.
Calendula: Calendula, also known as marigold, has been widely used on the skin to treat minor wounds, skin infections, burns, bee stings, sunburn, warts, and cancer. Calendula has been studied for reducing pain caused by otitis media. Some human studies suggest that calendula may possess mild anesthetic (pain-relieving) properties equal to those of similar non-herbal eardrop preparations. Further studies are needed before a conclusion can be made.
Use cautiously if allergic to plants in the Aster/Compositae family (such as ragweed, chrysanthemums, marigolds, or daisies). Use cautiously while driving or operating machinery. Avoid if pregnant or breastfeeding.
Chiropractic, Spinal Manipulative Therapy, Spinal Manipulation: Chiropractic is a healthcare discipline that focuses on the relationship between musculoskeletal structure (primarily the spine) and body function (as coordinated by the nervous system), and how this relationship affects the preservation and restoration of health. Although ear infections are treated with chiropractic manipulation with some success, well-designed clinical trials have not yet been conducted. Presently, there is insufficient evidence to support the use of chiropractic manipulation for the treatment of otitis media in children.
Avoid with vertebrobasilar vascular insufficiency, aneurysms, arteritis, or unstable spondylolisthesis. Avoid use on post-surgical areas of para-spinal tissue. Use cautiously with acute arthritis, brittle bone disease, conditions that cause decreased bone mineralization, bleeding disorders, migraines, or if at risk for tumors or metastasis of the spine. Use extra caution during cervical adjustments. Avoid if pregnant or breastfeeding due to a lack of scientific data.
Lavender: Oils from lavender flowers are used in aromatherapy, baked goods, candles, cosmetics, detergents, jellies, massage oils, perfumes, powders, shampoo, soaps, and teas. Limited available clinical study used a naturopathic eardrop called NHED (containing Allium sativum, Verbascum thapsus, Calendula flores, Hypericum perfoliatum, lavender, and vitamin E in olive oil) with and without an antibiotic and topical anesthetic. It was found that the ear pain was self-limiting and resolved after a few days with or without antibiotics. This evidence is early, and further research is needed before any conclusion about this treatment can be made.
Avoid if allergic or hypersensitive to lavender. Avoid with a history of seizures, bleeding disorders, eating disorders (such as anorexia or bulimia), or anemia (low levels of iron). Avoid if pregnant or breastfeeding.
Mullein: Mullein (Verbascum thapsus) has been used in natural medicine for centuries and is among the oldest known medicinal plants. There are some clinical studies using mullein in combination with other herbal products as an eardrop to treat earaches caused by ear infections. It is not clear what the effects of mullein alone are on ear infections because the product studied was a combination of different herbal products. Additional study is needed before a conclusion can be made regarding use of mullein for earache associated with acute otitis media.
Avoid if allergic/hypersensitive to mullein (Verbascum thapsus), its constituents, or any members of the Scrophulariaceae (figwort) family. Use cautiously if taking anticoagulants (blood thinners). There are reports that mullein may contain a toxin called rotenone, which is an insecticide. Avoid if pregnant or breastfeeding.
Probiotics: Probiotic capsules (containing Lactobacillus rhamnosus GG and LC705, Bifidobacterium breve 99, and Propionibacterium freudenreichii JS) were not shown to protect against ear infections in children. More research is needed to confirm these findings.
Probiotics are generally considered safe and well-tolerated. Avoid if allergic or hypersensitive to probiotics. Use cautiously if lactose intolerant. Caution is advised when using probiotics in neonates born prematurely or with immune deficiency.
Sanicle: Sanicle has been studied as a treatment for recurrent otitis media. More evidence is needed before a conclusion can be made.
Avoid if allergic or sensitive to sanicle. Use cautiously with stomach problems. Use cautiously if taking blood pressure-lowering or diuretic drugs. Avoid if pregnant or breastfeeding.
Fair negative scientific evidence:
Reflexology: Limited available study suggests that treatment given by a reflexologist is less effective (in terms of number of ear disorders, number of antibiotic treatments, number of sickness days, and duration of ear disorders) than treatment given by a general practitioner for ear infections.
Avoid with recent or healing foot fractures, unhealed wounds, or active gout flares affecting the foot. Use cautiously and seek prior medical consultation with osteoarthritis affecting the foot or ankle, or severe vascular disease of the legs or feet. Use cautiously with diabetes, heart disease, or the presence of a pacemaker, unstable blood pressure, cancer, active infections, past episodes of fainting (syncope), mental illness, gallstones, or kidney stones. Use cautiously if pregnant or breastfeeding. Reflexology should not delay diagnosis or treatment with more proven techniques or therapies.
Traditional or theoretical uses which lack sufficient evidence:
Garlic (Allium sativum): Garlic has been used traditionally for ear infections. It is crushed and diluted in a carrier oil, such as olive oil, which is then applied topically. A small clinical trial used a naturopathic eardrop mixture containing garlic,mullein,calendula,St. Johns wort, lavender, and vitamin E in olive oil, with and without an antibiotic and topical anesthetic. It was found that ear pain was self-limiting and resolved after a few days with or without antibiotics. Additional research is needed to make a conclusion.
Avoid if allergic or hypersensitive to garlic or other members of the Lilaceae(lily) family (like hyacinth, tulip, onion, leek, chive). Avoid with a history of bleeding problems, asthma, diabetes, low blood pressure, or thyroid disorders. Stop using supplemental garlic two weeks before dental/surgical/diagnostic procedures and avoid using immediately after such procedures to avoid bleeding problems. Avoid in supplemental doses if pregnant or breastfeeding.
St. John's wort (Hypericum perfoliatum): St. John's wort has been used traditionally for various kinds of pain, however, reliable evidence indicating effectiveness is currently lacking. In clinical study, a naturopathic eardrop mixture containing garlic,mullein,calendula, St. Johns wort, lavender, and vitamin E in olive oil, was used with and without an antibiotic and topical anesthetic. It was found that ear pain was self-limiting and resolved after a few days with or without antibiotics. This evidence is preliminary and further research is needed before any conclusion about this treatment can be made. It is currently unclear if St. John's wort is effective for chronic ear infections.
Avoid if allergic or hypersensitive to plants in the Hypericaceae family. Rare allergic skin reactions like itchy rash have been reported. Avoid with HIV/AIDS drugs (protease inhibitors) like indinavir (Crixivan?), or non-nucleoside reverse transcriptase inhibitors, like nevirapine (Viramune?). Avoid with immunosuppressant drugs (like cyclosporine, tacrolimus or myophenic acid). Avoid with organ transplants, suicidal symptoms or before surgery. Use cautiously with history of thyroid disorders. Use cautiously with drugs that are broken down by the liver, with monoamine oxidase inhibitors (MAOI) or selective serotonin reuptake inhibitors (SSRIS), digoxin, or birth control pills. Use cautiously with diabetes or with history of mania, hypomania (as in Bipolar Disorder), or affective illness. Avoid if pregnant or breastfeeding.

Prevention

Smoking avoidance: Ear infections are more common in children who are around cigarette smoke in the home. Even fumes from tobacco smoke on hair and clothes can affect the child.
Breastfeeding: Breastfeeding a baby helps improve resistance to infection and immunity. Also, breastfeed the baby in an upright position to prevent the possibility of infection.
Cleanliness: Washing the hands often helps stop infection from spreading by killing germs.
Immunization: Healthcare professionals recommend immunizing a child according to standards set by the U.S. Centers for Disease Control and Prevention (CDC). A doctor can review the immunizations recommended for a child with the parent. Current immunizations do not specifically prevent ear infections. However, they can prevent illnesses, such as influenza (flu) that often lead to ear infections. Having the child immunized with Prevnar? vaccine may help reduce the risk of ear infection. Prevnar? is a vaccine that protects infants and young children against pneumococcal disease (Streptococcus pneumoniae a major cause of pneumonia). According to one study, doctor visits by those who were diagnosed as having chronic ear infections and who took Prevnar? dropped about 20%, and there was a similar 20% reduction in the number of children who needed tube implants to fight the infections, and overall ear infections were reduced by 9%.
Other: Weaning a child from his or her pacifier on or before six months of age may help prevent ear infections; babies who use pacifiers after 12 months of age are more likely to develop ear infections.

Author information

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

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Finkelstein JA, Stille CJ, Rifas-Shiman SL, et al. Watchful waiting for acute otitis media: are parents and physicians ready? Pediatrics. 2005 Jun;115(6):1466-73.
Kashiwamura M, Chida E, Matsumura M, et al. The efficacy of Burow's solution as an ear preparation for the treatment of chronic ear infections. Otol Neurotol. 2004 Jan;25(1):9-13.
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Causes

Infection: Ear infections can start with a bacterial or viral infection (such as those causing common cold). In such cases, the middle ear becomes inflamed from the infection, and fluid builds up behind the eardrum. Bacteria cause about 65-75% of all ear infections. The most common types are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Viruses that may lead to ear infections include the respiratory syncytial virus (RSV), the most frequent type found, followed by influenza (flu) viruses.
Eustachian tube problems: Ear infections also may be associated with problems such as swelling within the eustachian tubes, the narrow passageways that connect the middle ear to the throat. Normally these tubes equalize pressure inside and outside the ear. But a child's eustachian tubes are narrower and shorter than those of an adult. This makes it easier for fluid to get trapped in the middle ear when the eustachian tubes dysfunction or become blocked during a cold. This provides a perfect breeding ground for infection. Also, just as the mucus in the nose gets thicker and harder to expel, fluid within the ear can also become thick and difficult to drain.
Adenoids (tonsils): Another factor in ear infections is swelling of the adenoids (tonsils). These are tissues located in the upper throat near where the eustachian tubes connect. Adenoids contain lymphocytes, or types of white blood cells that normally fight infection. But sometimes the adenoids themselves get infected or enlarged, blocking the eustachian tubes. Infection in the adenoids can also spread to the eustachian tubes, causing ear infections.
Immune function: Children also do not have fully developed immune systems, so it is easier for them to develop many illnesses, including ear infections.

Risk factors

Age: Children between ages six and 18 months are the most susceptible to ear infections, although ear infections are common from ages four months to four years.
Group child care: Children cared for in group settings, such as classrooms or daycare, are more likely to get colds and ear infections than are children who stay home.
Air quality: Children with exposure to tobacco smoke or higher levels of air pollution are at higher risk of ear infections.
Family history: Genetics (heredity) seems to play a role in the susceptibility to ear infections. A child has a greater chance of developing ear infections if a parent or sibling was diagnosed with the condition.
Race: Native Americans and Eskimos from Alaska or Canada tend to have more ear infections than do Caucasians. Hispanic children are also more susceptible to ear infections than Caucasian and African American children. Differences in the number of ear infections due to race are possibly due to genetic factors that affect the shape of the auditory tube.
Gender: Boys are affected more commonly than girls, but no specific causative factors have been found. Male sex is a minor determinant of infection.
Feeding position: Babies who drink from a bottle while lying down tend to have more ear infections than do babies who are held upright during feedings. Breastfeeding should also be performed sitting or standing upright, not lying down.
Season: Ear infections are most common during the fall and winter, probably due to decreased humidity when home heating is used. Dry air tends to cause more viruses (colds and flu) and ear infections. Dry air can dry out nasal passages, making them more susceptible to viral penetration into the body.
Birth defects or other medical conditions: Babies with cleft palate, a condition where the bones in the roof of the mouth have not grown together properly, or Down syndrome (mental retardation) are likely to get ear infections.
Allergies: Allergies can cause long-term congestion (stuffiness) in the nose that can affect how the eustachian tube works. Blocking this tube, which leads from the ear to the throat, can cause fluid to build up in the middle ear.
Repeat colds and upper respiratory infections: Most ear infections develop from colds or other upper respiratory infections.

Types of ear infections

Otitis externa: Otitis externa, or swimmer's ear, is an infection of the outer ear structures. It typically occurs in swimmers, but the since the cause of the infection is water trapped in the ear canal, bathing or showering may also cause this common infection. When water is trapped in the ear canal, bacteria that normally inhabit the skin and ear canal multiply, causing infection and irritation of the ear canal. If the infection progresses it may involve the outer ear.
Swimmer's ear is sometimes confused with otitis media (middle ear infections), especially when there is drainage from the ear (otorrhea). In middle ear infections, drainage only occurs if the tympanic membrane (ear drum) has either a perforation (hole) or bulges in the membrane.
Otitis media with effusion: When fluid forms in the middle ear, the condition is known as otitis media with effusion. This occurs in a recovering ear infection or when an ear infection is starting. Fluid can remain in the ear for weeks to months. When a discharge from the ear persists or repeatedly returns, this is sometimes called chronic middle ear infection. Fluid can remain in the ear up to three weeks following the infection. If not treated, chronic ear infections have potentially serious consequences such as temporary or permanent hearing loss.
All children with middle ear infection or fluid have some degree of hearing loss. The average hearing loss in ears with fluid is 24 decibels, equivalent to wearing ear plugs. If a child has a hearing loss, they should be examined by an ear, nose, and throat specialist at the earliest opportunity. Hearing loss can be temporary, lasting only a few days, to permanent in severe infections.
Suppurative otitis media: A condition called chronic suppurative otitis media (an ear infection with drainage lasting more than two weeks) can develop from repeat ear infections.
Otitis interna: Otitis interna, or inner ear infection, is inflammation of the inner ear. It is among the most common ear infections and is usually caused by water trapped inside the ear by earwax. Labyrinthitis is a type of inner ear infection that typically results in severe vertigo (dizziness) lasting for one or more days. It is thought to be caused by a viral inflammation of the vestibular labyrinth (the part of the inner ear responsible for balance). Individuals usually complain of a sudden onset of severe whirling vertigo (dizziness), nausea, and vomiting. The symptoms can be so severe and disabling that people frequently go to the emergency room for care and require drugs to help regain balance, such as meclizine (Antivert?). Symptoms typically subside over a few days, but may leave the individual with slight imbalance that slowly improves over weeks or months. Hearing loss rarely accompanies the vertigo (dizziness) in labyrinthitis.