Understanding the difference between otitis media with effusion and other forms of middle ear infection is important. Otitis media is a generic term defined as an inflammation of the middle ear without reference to a specific etiology or pathogenesis.
Scientists have long sought to uncover the structure and function of viruses. Viruses are unique in that they have been classified as both living and nonliving at various points in the history of biology. Viruses are particles that are capable of causing a number of diseases including cancer.
Viruses do not fit the definition of living organisms. Viruses are molecular aggregates of proteins and nucleic acids (see Chapter 2) and lack cells or metabolic systems. Furthermore, although viruses self-replicate, they can only do so by using materials from their hosts, and they are only able to multiply inside host cells.