Negative-strand RNA viruses (-ssRNA viruses) are a group of related viruses that have negative-sense, single-stranded genomes made of ribonucleic acid. They have genomes that act as complementary strands from which messenger RNA (mRNA) is synthesized by the viral enzyme RNA-dependent RNA polymerase (RdRp). During replication of the viral genome, RdRp synthesizes a positive-sense antigenome that it uses as a template to create genomic negative-sense RNA. Negative-strand RNA viruses also share a number of other characteristics: most contain a viral envelope that surrounds the capsid, which encases the viral genome, -ssRNA virus genomes are usually linear, and it is common for their genome to be segmented.
Negative-strand RNA viruses constitute the phylum Negarnaviricota, in the kingdom Orthornavirae and realm Riboviria. They are descended from a common ancestor that was a double-stranded RNA (dsRNA) virus, and they are considered to be a sister clade of reoviruses, which are dsRNA viruses. Within the phylum, there are two major branches that form two subphyla: Haploviricotina, whose members are mostly non-segmented and which encode an RdRp that synthesizes caps on mRNA, and Polyploviricotina, whose members are segmented and which encode an RdRp that snatches caps from host mRNAs. A total of six classes in the phylum are recognized.
Negative-strand RNA viruses are closely associated with arthropods and can be informally divided between those that are reliant on arthropods for transmission and those that are descended from arthropod viruses but can now replicate in vertebrates without the aid of arthropods. Prominent arthropod-borne -ssRNA viruses include the Rift Valley fever virus and the tomato spotted wilt virus. Notable vertebrate -ssRNA viruses include the Ebola virus, hantaviruses, influenza viruses, the Lassa fever virus, and the rabies virus.
https://en.wikipedia.org/wiki/Negative-strand_RNA_virus
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