Adenoviruses are a common cause of respiratory infections. There are about 25 serotypes and young children have typically had several exposures to adenoviral family by the time they enter kindergarten. Adenovirus is especially common in nursery school and is thought to cause about 20% of preschool fevers.
An older person with Adenovirus might have a scratchy throat or laryngitis. A preschooler can have more of a cough and cold, and perhaps conjunctivitis or an ear infection. The virus can sometimes cause a febrile illness called Acute Pharyngeal Fever, in which the child spikes a high fever every night for several days and look much better in the morning. The parents feel reassured with the fever down, but in the late afternoon the fever rises again. When the child comes to the office, there are often white splotches on the tonsils. The fevers often rise to 104, and then stop after about 3-5 days. Sometimes there is a faint, splotchy post viral rash.
Adenovirus alone do not need antibiotics, however sometimes there is a secondary ear infection, or bacterial tonsillitis. Viral infections can cause the tonsils, which are essentially antibody factories, to become puffed up. Sometimes bacterial get caught in the crevices and the child develops bad breath, and yellowish pus pockets on the tonsils. In these situations, antibiotics are used, even though the initial illness was viral driven.