For youngsters, the most common trigger of an ear infection is an upper respiratory viral infection, such as a chilly or the influenza. These disorders can make the Eustachian tube so puffy that air can no longer move into the middle ear. Allergies-- to plant pollen, dirt, animal dander, or food-- can create the same effect as a chilly or influenza, as can smoke, fumes, and also other ecological toxins. Attacking germs can inflict major chaos, transforming swelling into infection and prompting high temperatures.