The arthropod-borne viruses (arboviruses) and rodent-borne viruses represent ecologic groupings of viruses with complex transmission cycles involving arthropods or rodents. These viruses have diverse physical and chemical properties and are classified in several virus families.
Arboviruses and rodent-borne viruses are classified among the Arenaviridae, Bunyaviridae, Flaviviridae, Reoviridae, and Togaviridae families. The African hemorrhagic fever viruses are classified in the Filoviridae family (Table 38-1, Figure 38-1). A number of the diseases described here are considered emerging infectious diseases (see Chapter 29).
Table 38-1 Classification and Properties of Some Arthropod-Borne and Rodent-Borne Viruses |Favorite Table|Download (.pdf)
Table 38-1 Classification and Properties of Some Arthropod-Borne and Rodent-Borne Viruses
|Taxonomic Classification||Important Arbovirus and Rodent-Borne Virus Members||Virus Properties|
|Genus Arenavirus||New World: Guanarito, Junin, Machupo, Sabia, and Whitewater Arroyo viruses. Old World: Lassa and lymphocytic choriomeningitis viruses. Rodent borne||Spherical, 50–300 nm in diameter (mean, 110–130 nm). Genome: double-segmented, negative-sense and ambisense, single-stranded RNA, 10–14 kb in overall size. Virion contains a transcriptase. Four major polypeptides. Envelope. Replication: cytoplasm. Assembly: incorporate ribosomes and bud from plasma membrane|
|Genus Orthobunyavirus||Anopheles A and B, Bunyamwera, California encephalitis, Guama, La Crosse, Oropouche, and Turlock viruses. Arthropod borne (mosquitoes)||Spherical, 80–120 nm in diameter. Genome: triple-segmented, negative-sense or ambisense, single-stranded RNA, 11–19 kb in total size. Virion contains a transcriptase. Four major polypeptides. Envelope. Replication: cytoplasm. Assembly: budding into the Golgi|
|Genus Hantavirus||Hantaan virus (Korean hemorrhagic fever), Seoul virus (hemorrhagic fever with renal syndrome), Sin Nombre virus (hantavirus pulmonary syndrome). Rodent borne|
|Genus Nairovirus||Crimean-Congo hemorrhagic fever, Nairobi sheep disease, and Sakhalin viruses. Arthropod borne (ticks)|
|Genus Phlebovirus||Rift Valley fever, sandfly (Phlebotomus) fever, and Uukuniemi viruses. Arthropod borne (mosquitoes, sandflies, ticks)|
|Genus Marburgvirus||Marburg viruses||Long filaments, 80 nm in diameter × varying length (>10,000 nm), although most average ~1000 nm. Genome: negative-sense, nonsegmented, single-stranded RNA, 19 kb in size. Seven polypeptides. Envelope. Replication: cytoplasm. Assembly: budding from plasma membrane|
|Genus Ebolavirus||Ebola viruses|
|Genus Flavivirus||Brazilian encephalitis (Rocio virus), dengue, Japanese B encephalitis, Kyasanur Forest disease, louping ill, Murray Valley encephalitis, Omsk hemorrhagic fever, St. Louis encephalitis, tick-borne encephalitis, West Nile fever, and yellow fever viruses. Arthropod borne (mosquitoes, ticks)||Spherical, 40–60 nm in diameter. Genome: positive-sense, single-stranded RNA, 11 kb in size. Genome RNA infectious. Envelope. Three structural polypeptides, two glycosylated. Replication: cytoplasm. Assembly: within endoplasmic reticulum. All viruses serologically related|
|Genus Coltivirus||Colorado tick fever virus. Arthropod borne (ticks, mosquitoes)||Spherical, 60–80 nm in diameter. Genome: 10–12 segments of linear, double-stranded RNA, 16–27 kbp total size. No envelope. Ten to 12 structural polypeptides. Replication and assembly: cytoplasm (see Chapter 37)|
|Genus Orbivirus||African horse sickness and bluetongue viruses. Arthropod borne (mosquitoes)|
|Genus Alphavirus||Chikungunya, eastern, western, and Venezuelan equine encephalitis viruses, Mayaro, O'Nyong-nyong, Ross River, Semliki Forest, and Sindbis viruses. Arthropod borne (mosquitoes)||Spherical, 70 nm in diameter, nucleocapsid has 42 capsomeres. Genome: ...|