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%.
Yellow fever is a viral disease of typically short duration. In most cases, symptoms include fever, chills, loss of appetite, nausea, muscle pains – particularly in the back – and headaches. Symptoms typically improve within five days. In about 15% of people, within a day of improving the fever comes back, abdominal pain occurs, and liver damage begins causing yellow skin. If this occurs, the risk of bleeding and kidney problems is increased.
Arbovirus is an informal name for any virus that is transmitted by arthropod vectors. The term arbovirus is a portmanteau word. Tibovirus is sometimes used to more specifically describe viruses transmitted by ticks, a superorder within the arthropods. Arboviruses can affect both animals and plants. In humans, symptoms of arbovirus infection generally occur 3–15 days after exposure to the virus and last three or four days. The most common clinical features of infection are fever, headache, and malaise, but encephalitis and viral hemorrhagic fever may also occur.
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.
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.
Aedes aegypti, the yellow fever mosquito, is a mosquito that can spread dengue fever, chikungunya, Zika fever, Mayaro and yellow fever viruses, and other disease agents. The mosquito can be recognized by black and white markings on its legs and a marking in the form of a lyre on the upper surface of its thorax. This mosquito originated in Africa, but is now found in tropical, subtropical and temperate regions throughout the world.
Crimean–Congo hemorrhagic fever (CCHF) is a viral disease. Symptoms of CCHF may include fever, muscle pains, headache, vomiting, diarrhea, and bleeding into the skin. Onset of symptoms is less than two weeks following exposure. Complications may include liver failure. Survivors generally recover around two weeks after onset.
Oropouche fever is a tropical viral infection transmitted by biting midges and mosquitoes from the blood of sloths to humans. This disease is named after the region where it was first discovered and isolated at the Trinidad Regional Virus Laboratory in 1955 by the Oropouche River in Trinidad and Tobago. Oropouche fever is caused by a specific arbovirus, the Oropouche virus (OROV), of the Bunyaviridae family.
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.
An emerging infectious disease (EID) is an infectious disease whose incidence has increased recently, and could increase in the near future. The minority that are capable of developing efficient transmission between humans can become major public and global concerns as potential causes of epidemics or pandemics. Their many impacts can be economic and societal, as well as clinical. EIDs have been increasing steadily since at least 1940.
Orthobunyavirus is a genus of the Peribunyaviridae family in the order Bunyavirales. There are currently ~170 viruses recognised in this genus. These have been assembled into 103 species and 20 serogroups.
Bunyamwera orthobunyavirus (BUNV) is a negative-sense, single-stranded enveloped RNA virus. It is assigned to the Orthobunyavirus genus, in the Bunyavirales order.
Langat virus (LGTV) is a virus of the genus Flavivirus. The virus was first isolated in Malaysia in 1956 from a hard tick of the Ixodes genus. This virus is antigenically related to Omsk hemorrhagic fever virus, Kyasanur forest disease virus, Alkhurma virus, Louping ill virus and other viruses of the tick-borne encephalitis virus (TBEV) complex. The Langat virus does not pose a significant epidemiological threat in comparison with TBEV. There are no known cases of human diseases associated with LGTV. The Malaysian strain is naturally attenuated and induces neutralizing antibodies to tick-borne encephalitis virus (TBEV) and protection against other TBEV complex viruses in animals.
Tahyna orthobunyavirus ("TAHV") is a viral pathogen of humans classified in the California encephalitis virus (CEV) serogroup of the Orthobunyavirus family in the order Bunyavirales, which is endemic to Europe, Asia, Africa and possibly China.
Batai orthobunyavirus (BATV) is a RNA virus belonging to order Bunyavirales, genus Orthobunyavirus.
East Africa had a regional outbreak of Rift Valley fever in late 2006 that affected Kenya, Somalia, and Tanzania. During outbreak, 1062 people were infected with Rift Valley fever and 394 people died between December 2006 and December 2007. Rift Valley fever (RVF) is caused by a phlebovirus in the Bunyavirales order which is transmitted by mosquito bite and contact with infected animal blood; it mainly infects livestock that come into infectious contact with a viral reservoir but human beings can also be infected. The outbreak began after a heavy El Niño rain season across East Africa left greater than usual breeding ground for Aedes aegypti mosquitos, with particularly heavy rainfall over eastern Kenya, central Tanzania, and southern Somalia. While most people infected with the virus experience a relatively mild, flu-like illness without hospitalization, around 8% will develop a severe illness that can include eye disease, encephalitis, hemorrhagic fever and death. During this outbreak, of the 1,062 hospitalized, laboratory-confirmed RVF cases assays, 37% died.
Orthornavirae is a kingdom of viruses that have genomes made of ribonucleic acid (RNA), including genes which encode an RNA-dependent RNA polymerase (RdRp). The RdRp is used to transcribe the viral RNA genome into messenger RNA (mRNA) and to replicate the genome. Viruses in this kingdom share a number of characteristics which promote rapid evolution, including high rates of genetic mutation, recombination, and reassortment.
Lokern virus (LOKV) is a single-stranded, negative sense, tri-segmented RNA virus. It is a subtype of the Bunyamwera virus (BUNV) and closely related to the Main Drain virus (MDV). The virus is a natural reassortment that received its S and L segments from MDV while its M segment shows a relatively low percentage of nucleotide identity in relation to any other orthobunyavirus, suggesting it came from an unknown or extinct virus.
Aedes circumluteolus is a species of mosquito that is found throughout much of Sub-Saharan Africa. It is often found in tropical coastal lowlands and Bushveld savanna.
