Rift Valley fever (RVF) is a viral disease of humans and livestock that can cause mild to severe symptoms. The mild symptoms may include: fever, muscle pains, and headaches which often last for up to a week. The severe symptoms may include: loss of sight beginning three weeks after the infection, infections of the brain causing severe headaches and confusion, and bleeding together with liver problems which may occur within the first few days. Those who have bleeding have a chance of death as high as 50%.
Flaviviridae is a family of enveloped positive-strand RNA viruses which mainly infect mammals and birds. They are primarily spread through arthropod vectors. The family gets its name from the yellow fever virus; flavus is Latin for "yellow", and yellow fever in turn was named because of its propensity to cause jaundice in victims. There are 89 species in the family divided among four genera. Diseases associated with the group include: hepatitis (hepaciviruses), hemorrhagic syndromes, fatal mucosal disease (pestiviruses), hemorrhagic fever, encephalitis, and the birth defect microcephaly (flaviviruses).
Flavivirus, renamed Orthoflavivirus in 2023, is a genus of positive-strand RNA viruses in the family Flaviviridae. The genus includes the West Nile virus, dengue virus, tick-borne encephalitis virus, yellow fever virus, Zika virus and several other viruses which may cause encephalitis, as well as insect-specific flaviviruses (ISFs) such as cell fusing agent virus (CFAV), Palm Creek virus (PCV), and Parramatta River virus (PaRV). While dual-host flaviviruses can infect vertebrates as well as arthropods, insect-specific flaviviruses are restricted to their competent arthropods. The means by which flaviviruses establish persistent infection in their competent vectors and cause disease in humans depends upon several virus-host interactions, including the intricate interplay between flavivirus-encoded immune antagonists and the host antiviral innate immune effector molecules.
Bunyavirales is an order of segmented negative-strand RNA viruses with mainly tripartite genomes. Member viruses infect arthropods, plants, protozoans, and vertebrates. It is the only order in the class Ellioviricetes. The name Bunyavirales derives from Bunyamwera, where the original type species Bunyamwera orthobunyavirus was first discovered. Ellioviricetes is named in honor of late virologist Richard M. Elliott for his early work on bunyaviruses.
An arenavirus is a bi- or trisegmented ambisense RNA virus that is a member of the family Arenaviridae. These viruses infect rodents and occasionally humans. A class of novel, highly divergent arenaviruses, properly known as reptarenaviruses, have also been discovered which infect snakes to produce inclusion body disease, mostly in boa constrictors. At least eight arenaviruses are known to cause human disease. The diseases derived from arenaviruses range in severity. Aseptic meningitis, a severe human disease that causes inflammation covering the brain and spinal cord, can arise from the lymphocytic choriomeningitis virus. Hemorrhagic fever syndromes, including Lassa fever, are derived from infections such as Guanarito virus, Junin virus, Lassa virus, Lujo virus, Machupo virus, Sabia virus, or Whitewater Arroyo virus. Because of the epidemiological association with rodents, some arenaviruses and bunyaviruses are designated as roboviruses.
Viral hemorrhagic fevers (VHFs) are a diverse group of animal and human illnesses. VHFs may be caused by five distinct families of RNA viruses: the families Filoviridae, Flaviviridae, Rhabdoviridae, and several member families of the Bunyavirales order such as Arenaviridae, and Hantaviridae. All types of VHF are characterized by fever and bleeding disorders and all can progress to high fever, shock and death in many cases. Some of the VHF agents cause relatively mild illnesses, such as the Scandinavian nephropathia epidemica, while others, such as Ebola virus, can cause severe, life-threatening disease.
Thogotovirus is a genus of enveloped RNA viruses, one of seven genera in the virus family Orthomyxoviridae. Their single-stranded, negative-sense RNA genome has six or seven segments. Thogotoviruses are distinguished from most other orthomyxoviruses by being arboviruses – viruses that are transmitted by arthropods, in this case usually ticks. Thogotoviruses can replicate in both tick cells and vertebrate cells; one subtype has also been isolated from mosquitoes. A consequence of being transmitted by blood-sucking vectors is that the virus must spread systemically in the vertebrate host – unlike influenza viruses, which are transmitted by respiratory droplets and are usually confined to the respiratory system.
Phlebovirus is one of twenty genera of the family Phenuiviridae in the order Bunyavirales. The genus contains 66 species. It derives its name from Phlebotominae, the vectors of member species Naples phlebovirus, which is said to be ultimately from the Greek phlebos, meaning "vein". The proper word for "vein" in ancient Greek is however phleps (φλέψ).
Alkhurma virus (ALKV) is a zoonotic virus of the Flaviviridae virus family. ALKV causes Alkhurma hemorrhagic fever (AHF), or alternatively termed as Alkhurma hemorrhagic fever virus, and is mainly based in Saudi Arabia.
Anaplasma phagocytophilum is a Gram-negative bacterium that is unusual in its tropism to neutrophils. It causes anaplasmosis in sheep and cattle, also known as tick-borne fever and pasture fever, and also causes the zoonotic disease human granulocytic anaplasmosis.
Orthonairovirus is a genus of viruses in the family Nairoviridae of the order Bunyavirales which includes viruses with circular, negative-sense single stranded RNA. The name is derived from the Nairobi sheep disease which affects the gastrointestinal tracts of sheep and goats. All viruses in this genus are tick-borne viruses with human or other vertebrate hosts.
Deer tick virus (DTV) is a virus in the genus Flavivirus spread via ticks that causes encephalitis.
Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne infection caused by Dabie bandavirus also known as the SFTS virus, first reported between late March and mid-July 2009 in rural areas of Hubei and Henan provinces in Central China.
Heartland bandavirus, sometimes called Heartland virus (HRTV), is a tick-borne phlebovirus of the Bhanja virus serocomplex discovered in 2009. The lone star tick transmits the virus to people when feeding on blood. As of 2017, only five states in the Central United States have reported 20 human infections, namely Arkansas, Indiana, Missouri, Oklahoma, and Tennessee; symptoms resemble those of two other tick-borne infections ehrlichiosis and anaplasmosis. The reservoir host is unknown, but deer, raccoon, coyotes, and moose in 13 different states have antibody titers against the virus. By 2023 over 50 human infections were reported in at least eleven states.
Batai orthobunyavirus (BATV) is a RNA virus belonging to order Bunyavirales, genus Orthobunyavirus.
Cache Valley orthobunyavirus (CVV) is a member of the order Bunyavirales, genus Orthobunyavirus, and serogroup Bunyamwera, which was first isolated in 1956 from Culiseta inornata mosquitos collected in Utah's Cache Valley. CVV is an enveloped arbovirus, nominally 80–120 nm in diameter, whose genome is composed of three single-stranded, negative-sense RNA segments. The large segment of related bunyaviruses is approximately 6800 bases in length and encodes a probable viral polymerase. The middle CVV segment has a 4463-nucleotide sequence and the smallest segment encodes for the nucleocapsid, and a second non-structural protein. CVV has been known to cause outbreaks of spontaneous abortion and congenital malformations in ruminants such as sheep and cattle. CVV rarely infects humans, but when they are infected it has caused encephalitis and multiorgan failure.
West Nile virus (WNV) is a single-stranded RNA virus that causes West Nile fever. It is a member of the family Flaviviridae, from the genus Flavivirus, which also contains the Zika virus, dengue virus, and yellow fever virus. The virus is primarily transmitted by mosquitoes, mostly species of Culex. The primary hosts of WNV are birds, so that the virus remains within a "bird–mosquito–bird" transmission cycle. The virus is genetically related to the Japanese encephalitis family of viruses. Humans and horses both exhibit disease symptoms from the virus, and symptoms rarely occur in other animals.
Phenuiviridae is a family of negative-strand RNA viruses in the order Bunyavirales. Ruminants, camels, humans, and mosquitoes serve as natural hosts. Until 2011, member genus Phlebovirus was the only genus of the family with viruses causing disease in humans except Dabie bandavirus.
Civet SARS-CoV is a coronavirus associated with severe acute respiratory syndrome coronavirus (SARS-CoV), which infected humans and caused SARS events from 2002 to 2003. It infected the masked palm civet. The severe acute respiratory syndrome coronavirus (SARS-CoV) is highly similar, with a genome sequence similarity of about 99.8%. Because several patients infected at the early stage of the epidemic had contact with fruit-eating Japanese raccoon dog in the market, tanuki may be a direct source of human SARS coronavirus. At the end of 2003, four more people in Guangzhou, China, were infected with the disease. Sequence analysis found that the similarity with the tanuki virus reached 99.9%, and the SARS coronavirus was also caused by cases of tanuki transmission.
Bunyaviridae nonstructural S proteins (NSs) are synthesized by viral DNA/RNA and do not play a role in the replication or the viral protein coating. The nonstructural S segment (NSs) created by Bunyaviridae virus family, are able to interact with the human immune system, in order to increase their replication in infected cells. Understanding this mechanism can have global health impacts.
