Enteroviruses are a group of viruses that cause a number of infectious illnesses which are usually mild. However if they infect the central nervous system, they can cause serious illness. The two most common ones are echovirus and coxsackievirus, but there are several others. Enteroviruses also cause polio and hand, foot and mouth disease (HFMD).
The vast majority of people infected with enteroviruses—over 90%—will either have no symptoms or have non-specific symptoms, such as sudden fever. A wide range of symptoms can be caused by enteroviruses but most often include fever, mild respiratory symptoms, flu-like illness with fever and muscle aches, fever with a rash and gastrointestinal symptoms.