Echoviruses are related to poliovirus and more distantly the common-cold causing rhinoviruses and foot and mouth disease virus. Infection is usually benign, but occasionally these viruses can cause serious illness, particularly when they infect the nervous system, causing encephalitis or meningitis (infections of the brain). Echoviruses can also cause myocarditis and pericarditis (infections of the heart) and liver disease.

The first stage of infection is when the virus attaches to the cell. To gain entry to the host-cell, viruses attach to a specific molecule on the cell-surface called a receptor. The receptor will perform a legitimate function for the cell, but viruses have evolved to exploit their presence. In the case of echoviruses, the receptor's proper function is to protect the cell from attack by the body's immune system. Scientists study how the virus attaches to the cell because this knowledge can be used to develop medicines to combat viral diseases.