One of the divisions of the enterovirus subgroup, within the picornavirus group of viruses. The name is derived from the term enteric cytopathogenic human orphan virus. More than 34 antigenic types exist. Only certain types have been associated with human illnesses, particularly with aseptic meningitis and febrile disease. Their epidemiology is similar to that of other enteroviruses. Echoviruses resemble polioviruses and coxsackieviruses in size (about 28 nanometers) and in many other properties. Diagnosis is made by isolation and typing of the viruses in tissue culture. Antibodies form during convalescence.Animal virus Enterovirus Picornaviridae