The New ECHO Viruses and Their Role in Human Disease

A recent estimate places the number of new human viruses which have been uncovered since 1948 at 70. The dilemma which this appalling number of newcomers presents to students of infectious disease involves many problems in virology as well as the important question, what role do these agents play in human disease? As for the new and growing ECHO group of enteric viruses, now numbering 20, an encouraging beginning has been made: It has been possible to evaluate at least some of these agents in terms of their disease-producing potential and to place them with respect to other viral enteric pathogens, namely, the Coxsackie and poliovirus groups. In fact, the 20 ECHO, 24 Coxsackie, and 3 polioviruses have recently been joined together to form the Enterovirus group.¹The reasons for this grouping are the similarities between the three families of viruses: They are all common inhabitants of the human