Infection causes fever. Diarrhea is almost always infectious in origin. Colds and allergies cause runny noses.
High fever damages the brain.
108 degrees causes irreversible damage - that is heat stroke. Blowing cigaret smoke in the ear helps earache pain. Bathwater in the ear causes ear infection. It causes clean ears. Excessive water in the ear of an older child or adult can cause swimmers ear , but water cannot readily enter an infants ear in the bathtub because the little hairs and surface tension keep the air bubble trapped in the auditory canal and the canal stays dry.