ABSTRACT
Early attempts to classify viruses were based on their pathogenic properties, and the only feature common to many of the viruses placed together in such groupings was that of organ tropism or disease symptom (e.g. viruses causing hepatitis or respiratory disease). Other more fundamental aspects (e.g. virus structure and composition) led to the consensus that these initial attempts at classification were inadequate and in the late 1950s and early 1960s, hundreds of new viruses were isolated, highlighting the need for a robust classification system. In 1966 the International Committee on Nomenclature ofViruses (ICNV) was established at the International Congress of Microbiology held in Moscow. From this beginning, the present classification scheme has evolved, and acceptance of the characteristics to be considered and their respective weighting has become universal.
