Viral syndromes

This chapter focuses on several viral syndromes. The impression that viral infections dominate is strengthened if the abundance of subclinical virus infections is considered, in particular those in children. The most serious medical consequences of viral pneumonia are encountered in the old, the newborn, or the patient with a circulatory or respiratory handicap. Influenza is a cause of increased mortality among the old, while RS virus is the most important respiratory virus infection in small children. Fever and a reddened sore throat are among the most common symptoms of infection, and are seen in association with many virus infections. The predominant number of cases of pharyngitis in children and young adults are because of virus infections. Rotavirus is recognized by its characteristic double-layered capsid with cubical symmetry and by its size, 70 nm in diameter. There are rotaviruses of many different animal species, and some have antigenic and biological properties in common with the three human serotypes.