The work of the International Committee on Taxonomy of Viruses

The assignment of a virus to a specific family, genus or species is an important criterion in terms of risk assessment when it is used as a donor or recipient for genetic engineering work. Virus taxonomy refers to the naming of viruses, virus families and genera, which are defined by an international body, the International Committee on Taxonomy of Viruses (ICTV). This body currently consists of about 500 virologists within the International Union of Microbiological Societies .

In the original classification of viruses by André Lwoff, Robert W. Horne and Paul Tournier ( LHT system ), the nature of the viral genome (DNA or RNA), the symmetry of the capsid, the presence of a lipid envelope, and the size of the virion and capsid were used as characteristics. From 1971 onwards, an expanded classification named after David Baltimore was used, which used the viral genome (DNA or RNA), the presence of double- or single-stranded nucleic acids (in the case of RNA, also the polarity), any segmentation, the linear or circular topology of the genome, the shape (symmetry) of the capsid, the presence of an envelope, the arrangement of genes within the genome, the replication strategy (depending on genome structure), and the virus size as characteristics. Baltimore Classification The ICTV's primary focus is on similarities in the nucleotide sequence ( sequence homology ) between two viruses. The ICTV is continuously working on standardizing and organizing the taxonomic names of viruses, as well as viroids, virusoids, prions, and retrotransposons. When a new virus is discovered, the ICTV assigns it an internationally valid and scientifically binding name.

The ZKBS addresses the taxonomic classification of viruses in the general section of its statements on genetic engineering work with viruses. If there is currently little data available regarding the transmission routes or pathogenicity of the virus in question, the ZKBS bases its risk assessment on previously known, classified viruses from the same family or genus according to the ICTV taxonomy.