Kunjin virus
Encyclopedia
Kunjin virus is a zoonotic
virus
of the family Flaviviridae
and the genus Flavivirus
. It is a subtype of West Nile Virus
endemic to Oceania
.
in 1960.
The name of Kunjin virus derives from an Aboriginal
clan living on the Mitchell River
close to where the virus was first isolated in Kowanyama, northern Queensland
.
virus
of the family Flaviviridae
and the genus Flavivirus
. It is an arbovirus
which is transmitted by mosquito
es and is part of the Japanese encephalitis
serological complex. It is antigenically and genetically very similar to West Nile virus
and in 1999 was reclassified as a subtype of WNV. Its genome
is positive-sense
single stranded RNA
made up of 10,644 nucleotide
s.
disease or a non-encephalitic disease. Non-encephalitic Kunjin virus disease can cause symptoms including acute febrile
illness, headache
, arthralgia
, myalgia
, fatigue and rash
. Kunjin virus encephalitis features acute febrile meningoencephalitis
.
Both forms of Kunjin virus disease are milder than the diseases caused by West Nile virus and Murray Valley encephalitis virus
.
, a major example is the Nankeen Night Heron
. It is also passed to horses and humans. The virus been isolated in mosquitoes in South East Asia but in humans, only in Australia. It has been found all over Australia and is particularly prevalent in areas near wetland
s and rivers.
The control of Kunjin virus is achieved in the same ways as other mosquito-born diseases. These include individuals using insect repellent
, wearing long sleeved clothes and avoiding areas where mosquitoes are particularly prevalent. Habitat control by government agencies can take the form of reducing the amount of water available for mosquitoes to breed in, and the use of insecticide
s. There is no available vaccine
against Kunjin virus.
and the University of Queensland
found that modified Kunjin virus particles injected into mice
were able to deliver a gene
into the immune system
targeting cancer
cells. This research may lead to vaccines for cancer and HIV
.
Zoonosis
A zoonosis or zoonoseis any infectious disease that can be transmitted from non-human animals to humans or from humans to non-human animals . In a study of 1415 pathogens known to affect humans, 61% were zoonotic...
virus
Virus
A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...
of the family Flaviviridae
Flaviviridae
The Flaviviridae are a family of viruses that are primarily spread through arthropod vectors . The family gets its name from Yellow Fever virus, a type virus of Flaviviridae; flavus means yellow in Latin...
and the genus Flavivirus
Flavivirus
Flavivirus is a genus of the family Flaviviridae. This genus includes the West Nile virus, dengue virus, tick-borne encephalitis virus, yellow fever virus, and several other viruses which may cause encephalitis....
. It is a subtype of West Nile Virus
West Nile virus
West Nile virus is a virus of the family Flaviviridae. Part of the Japanese encephalitis antigenic complex of viruses, it is found in both tropical and temperate regions. It mainly infects birds, but is known to infect humans, horses, dogs, cats, bats, chipmunks, skunks, squirrels, domestic...
endemic to Oceania
Oceania
Oceania is a region centered on the islands of the tropical Pacific Ocean. Conceptions of what constitutes Oceania range from the coral atolls and volcanic islands of the South Pacific to the entire insular region between Asia and the Americas, including Australasia and the Malay Archipelago...
.
History
The virus was first isolated from Culex annulirostris mosquitoes in AustraliaAustralia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
in 1960.
The name of Kunjin virus derives from an Aboriginal
Indigenous Australians
Indigenous Australians are the original inhabitants of the Australian continent and nearby islands. The Aboriginal Indigenous Australians migrated from the Indian continent around 75,000 to 100,000 years ago....
clan living on the Mitchell River
Mitchell River (Queensland)
The Mitchell River is a river in the Far North Queensland region of Australia. The river begins on the Atherton Tableland about northwest of Cairns, and flows about northwest across Cape York Peninsula from Mareeba to the Gulf of Carpentaria....
close to where the virus was first isolated in Kowanyama, northern Queensland
Queensland
Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
.
Virology
Kunjin virus is a zoonoticZoonosis
A zoonosis or zoonoseis any infectious disease that can be transmitted from non-human animals to humans or from humans to non-human animals . In a study of 1415 pathogens known to affect humans, 61% were zoonotic...
virus
Virus
A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...
of the family Flaviviridae
Flaviviridae
The Flaviviridae are a family of viruses that are primarily spread through arthropod vectors . The family gets its name from Yellow Fever virus, a type virus of Flaviviridae; flavus means yellow in Latin...
and the genus Flavivirus
Flavivirus
Flavivirus is a genus of the family Flaviviridae. This genus includes the West Nile virus, dengue virus, tick-borne encephalitis virus, yellow fever virus, and several other viruses which may cause encephalitis....
. It is an arbovirus
Arbovirus
Arbovirus is a term used to refer to a group of viruses that are transmitted by arthropod vectors. The word arbovirus is an acronym . Some arboviruses are able to cause emergent disease.-Transmission:...
which is transmitted by mosquito
Mosquito
Mosquitoes are members of a family of nematocerid flies: the Culicidae . The word Mosquito is from the Spanish and Portuguese for little fly...
es and is part of the Japanese encephalitis
Japanese Encephalitis
Japanese encephalitis —previously known as Japanese B encephalitis to distinguish it from von Economo's A encephalitis—is a disease caused by the mosquito-borne Japanese encephalitis virus. The Japanese encephalitis virus is a virus from the family Flaviviridae. Domestic pigs and wild birds are...
serological complex. It is antigenically and genetically very similar to West Nile virus
West Nile virus
West Nile virus is a virus of the family Flaviviridae. Part of the Japanese encephalitis antigenic complex of viruses, it is found in both tropical and temperate regions. It mainly infects birds, but is known to infect humans, horses, dogs, cats, bats, chipmunks, skunks, squirrels, domestic...
and in 1999 was reclassified as a subtype of WNV. Its genome
Genome
In modern molecular biology and genetics, the genome is the entirety of an organism's hereditary information. It is encoded either in DNA or, for many types of virus, in RNA. The genome includes both the genes and the non-coding sequences of the DNA/RNA....
is positive-sense
Sense (molecular biology)
In molecular biology and genetics, sense is a concept used to compare the polarity of nucleic acid molecules, such as DNA or RNA, to other nucleic acid molecules...
single stranded RNA
RNA
Ribonucleic acid , or RNA, is one of the three major macromolecules that are essential for all known forms of life....
made up of 10,644 nucleotide
Nucleotide
Nucleotides are molecules that, when joined together, make up the structural units of RNA and DNA. In addition, nucleotides participate in cellular signaling , and are incorporated into important cofactors of enzymatic reactions...
s.
Symptoms and prognosis
Infection with the virus often causes no symptoms, but it can lead to either an encephaliticEncephalitis
Encephalitis is an acute inflammation of the brain. Encephalitis with meningitis is known as meningoencephalitis. Symptoms include headache, fever, confusion, drowsiness, and fatigue...
disease or a non-encephalitic disease. Non-encephalitic Kunjin virus disease can cause symptoms including acute febrile
Fever
Fever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...
illness, headache
Headache
A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the...
, arthralgia
Arthralgia
Arthralgia literally means joint pain; it is a symptom of injury, infection, illnesses or an allergic reaction to medication....
, myalgia
Myalgia
Myalgia means "muscle pain" and is a symptom of many diseases and disorders. The most common causes are the overuse or over-stretching of a muscle or group of muscles. Myalgia without a traumatic history is often due to viral infections...
, fatigue and rash
Rash
A rash is a change of the skin which affects its color, appearance or texture. A rash may be localized in one part of the body, or affect all the skin. Rashes may cause the skin to change color, itch, become warm, bumpy, chapped, dry, cracked or blistered, swell and may be painful. The causes, and...
. Kunjin virus encephalitis features acute febrile meningoencephalitis
Meningoencephalitis
Meningoencephalitis is a medical condition that simultaneously resembles both meningitis, which is an infection or inflammation of the meninges, and encephalitis, which is an infection or inflammation of the brain.-Causes:...
.
Both forms of Kunjin virus disease are milder than the diseases caused by West Nile virus and Murray Valley encephalitis virus
Murray Valley encephalitis virus
Murray Valley encephalitis virus is a zoonotic flavivirus endemic to northern Australia and Papua New Guinea. It is the causal agent of Murray Valley encephalitis and in humans can cause permanent neurological disease or death...
.
Transmission and control
Kunjin virus is transmitted by mosquito vectors, especially the Culex annulirostris. They pass the virus to waterbird reservoir hostsHost (biology)
In biology, a host is an organism that harbors a parasite, or a mutual or commensal symbiont, typically providing nourishment and shelter. In botany, a host plant is one that supplies food resources and substrate for certain insects or other fauna...
, a major example is the Nankeen Night Heron
Nankeen Night Heron
The Nankeen Night Heron, Nycticorax caledonicus, also commonly referred to as the Rufous Night Heron, and in Melanesia as Melabaob, is a medium-sized heron. It is found throughout much of Australia except the arid inland, Indonesia, the Philippines, Papua New Guinea and Melanesia...
. It is also passed to horses and humans. The virus been isolated in mosquitoes in South East Asia but in humans, only in Australia. It has been found all over Australia and is particularly prevalent in areas near wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....
s and rivers.
The control of Kunjin virus is achieved in the same ways as other mosquito-born diseases. These include individuals using insect repellent
Insect repellent
An insect repellent is a substance applied to skin, clothing, or other surfaces which discourages insects from landing or climbing on that surface. There are also insect repellent products available based on sound production, particularly ultrasound...
, wearing long sleeved clothes and avoiding areas where mosquitoes are particularly prevalent. Habitat control by government agencies can take the form of reducing the amount of water available for mosquitoes to breed in, and the use of insecticide
Insecticide
An insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
s. There is no available vaccine
Vaccine
A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins...
against Kunjin virus.
Use in medicine
In 2005, scientists at the Queensland Institute of Medical ResearchQueensland Institute of Medical Research
The Queensland Institute of Medical Research is one of Australia’s largest medical research institutes, and is recognised worldwide for the quality of its research. QIMR was established in 1945 by an Act of the Government of Queensland. The original purpose of the Institute was to further the...
and the University of Queensland
University of Queensland
The University of Queensland, also known as UQ, is a public university located in state of Queensland, Australia. Founded in 1909, it is the oldest and largest university in Queensland and the fifth oldest in the nation...
found that modified Kunjin virus particles injected into mice
Mouse
A mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles...
were able to deliver a gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
into the immune system
Immune system
An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...
targeting cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
cells. This research may lead to vaccines for cancer and HIV
HIV
Human immunodeficiency virus is a lentivirus that causes acquired immunodeficiency syndrome , a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive...
.