Heartland banyangvirus | |
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Virus classification | |
(unranked): | Virus |
Realm: | Riboviria |
Phylum: | Negarnaviricota |
Class: | Ellioviricetes |
Order: | Bunyavirales |
Family: | Phenuiviridae |
Genus: | Banyangvirus |
Species: | Heartland banyangvirus |
Synonyms [1] | |
Heartland virus |
Heartland banyangvirus, 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 Midwestern 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.
The Heartland virus (HRTV) was discovered in 2009 in northwestern Missouri by Dr. Scott Folk of Heartland Regional Medical Center in St. Joseph, Missouri. [2] The virus was first proven to infect humans in June 2009 when two farmers, living 60 miles (97 km) apart, presented with fever, fatigue, diarrhea, thrombocytopenia, and leukopenia. [3] The Lone Star Tick transmits the virus to people when feeding on blood.
The Heartland virus is part of the Bunyavirales order of viruses which contain 3 segments of −ssRNA. The genus of the virus is Phlebovirus and the species is the Heartland virus. [4] The SFTS virus from China, discovered in 2011, is a related species causing a similar disease.[ citation needed ]
In 2013, researchers from the CDC and Missouri Western State University first isolated the Heartland virus (HRTV) from the Lone Star Tick ( Amblyomma americanum ). [4] [5] As of 2013 work continued to identify the reservoir host, [4] as HRTV has not been isolated from any wild or domestic animals though many white-tailed deer and raccoon from northwestern Missouri had antibodies to HRTV, suggesting that they may be hosts.
In a 2015 retrospective study using convenience samples of different wild animal sera deer, raccoon, coyotes, and moose had antibodies against HRTV. They lived in thirteen states: Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Missouri, North Carolina, Tennessee, Texas, but also New Hampshire, Maine and Vermont. The infections could have occurred as early as 2003, based on the estimated ages of affected deer. Since the Lone Star tick does not occur in northern New England it is assumed that a second type of tick can carry HRTV. [6]
Signs and symptoms include fever in excess of 100.4 °F (38 °C), lethargy (weakness), headaches, muscle pain (myalgia), loss of appetite, nausea, diarrhea, weight loss, joint pain (arthralgia), low white blood cell count (leukopenia) and easy bruising due to a low platelet count (thrombocytopenia). Elevated liver transaminases may also be present. [7]
All known human cases have been reported from five U.S. states: Arkansas, Indiana, Missouri, Oklahoma, and Tennessee. Most people infected were spending time outdoors in regions where ticks are endemic. Most infections are diagnosed between May and September. People usually report having been bitten by a tick within two weeks prior to seeking health care.[ citation needed ]
Diagnosis is through the elimination of other causes of infectious diseases with related symptoms like ehrlichiosis and anaplasmosis or if the patient fails to respond to treatment with the antibiotic doxycycline. RT-PCR may then be used to detect viral ssRNA in the blood. Antibody titers against the virus may also be used to indicate infection with the Heartland virus. [8]
Treatment is non-specific. Antibiotics are not useful against viruses. Intravenous fluid administration and medications for the relief of pain are currently the best options. [9]
When planning to spend time outdoors in areas where the virus is known or suspected to be harbored by ticks, it is recommended that one cover the body completely with long sleeves and pants, and to avoid bushy and wooded areas. Although ticks are not consistently repelled by DEET-containing repellents, insect repellents should still be applied to one's body and gear. It is recommended that one perform thorough tick checks after being outside, and to remove any tick immediately. If a tick is found, one should remove the tick by the head, preferably with a pair of fine-tipped tweezers. Squeezing the abdomen of a tick while it is attached can force viruses and bacteria into the wound, increasing the chance of infection. Crushing an unattached tick will also release bacteria and viruses from its abdomen, which may then be able to enter a wound or burrow through the skin.[ citation needed ]
More than 20 human infections have been reported in the United States. [10]
Year | Location | Deaths | Cases |
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2009 | Northwestern Missouri | 0 | 2 |
2012–2013 [8] | Missouri, Tennessee [11] | 1 | 6 |
2014 | Missouri, [12] Oklahoma [13] | 1 | 3 |
2017 | Northwestern Arkansas, [10] Indiana [14] | 0 | 3 |
Ehrlichiosis is a tick-borne disease of dogs usually caused by the organism Ehrlichia canis. Ehrlichia canis is the pathogen of animals. Humans can become infected by E. canis and other species after tick exposure. German Shepherd Dogs are thought to be susceptible to a particularly severe form of the disease; other breeds generally have milder clinical signs. Cats can also be infected.
Babesiosis is a malaria-like parasitic disease caused by infection with the eukaryotic parasite Babesia, an alveolate in the phylum Apicomplexa. Human babesiosis transmission via tick bite is most common in the Northeastern and Midwestern United States and parts of Europe, and sporadic throughout the rest of the world. It occurs in warm weather. People can get infected with Babesia parasites by the bite of an infected tick, by getting a blood transfusion from an infected donor of blood products, or by congenital transmission . Ticks transmit the human strain of babesiosis, so it often presents with other tick-borne illnesses such as Lyme disease. After trypanosomes, Babesia is thought to be the second-most common blood parasite of mammals, and they can have a major impact on health of domestic animals in areas without severe winters. In cattle the disease is known as Texas cattle fever, redwater, or piroplasmosis.
Arbovirus is an informal name used to refer to any viruses that are transmitted by arthropod vectors. The word arbovirus is an acronym. The 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 hemorrhagic fever may also occur.
Tick-borne diseases, which afflict humans and other animals, are caused by infectious agents transmitted by tick bites. They are caused by infection with a variety of pathogens, including rickettsia and other types of bacteria, viruses, and protozoa. Because individual ticks can harbor more than one disease-causing agent, patients can be infected with more than one pathogen at the same time, compounding the difficulty in diagnosis and treatment. 16 tick-borne diseases of humans are known, or which four have been discovered since 2013.
Bunyavirales is an order of negative-sense single-stranded RNA viruses. It is the only order in the class Ellioviricetes. It was formerly known as Bunyaviridae family of viruses. 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 emerging infectious disease (EID) is an infectious disease whose incidence has increased recently, and could increase in the near future. Such diseases do not respect national boundaries. 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.
Phlebovirus is one of four genera of the family Phenuiviridae in the order Bunyavirales. The genus currently comprises 10 species. It derives its name from Phlebotominae, the vectors of member species Sandfly fever 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).
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.
Powassan virus (POWV) is a Flavivirus transmitted by ticks, found in North America and in the Russian Far East. It is named after the town of Powassan, Ontario, where it was identified in a young boy who eventually died from it. It can cause encephalitis, an infection of the brain. No vaccine or antiviral drug exists. Prevention of tick bites is the best precaution.
Anaplasmosis is a disease caused by a rickettsial parasite of ruminants, Anaplasma spp and is therefore related to rickettsial disease. The microorganisms are Gram-negative, and infect red blood cells. They are transmitted by natural means through a number of haematophagous species of ticks. The Ixodes tick that commonly transmits Lyme disease also spreads anaplasmosis.
Ehrlichiosis is a tick-borne bacterial infection, caused by bacteria of the family Anaplasmataceae, genera Ehrlichia and Anaplasma. These obligate intracellular bacteria infect and kill white blood cells.
Amblyomma americanum, also known as the lone star tick, the northeastern water tick, or the turkey tick, is a type of tick indigenous to much of the eastern United States and Mexico, that bites painlessly and commonly goes unnoticed, remaining attached to its host for as long as seven days until it is fully engorged with blood. It is a member of the phylum Arthropoda, class Arachnida. The adult lone star tick is sexually dimorphic, named for a silvery-white, star-shaped spot or "lone star" present near the center of the posterior portion of the adult female shield (scutum); adult males conversely have varied white streaks or spots around the margins of their shields.
Ehrlichia chaffeensis is an obligate intracellular, Gram-negative species of Rickettsiales bacteria. It is a zoonotic pathogen transmitted to humans by the lone star tick. It is the causative agent of human monocytic ehrlichiosis.
Human granulocytic anaplasmosis (HGA) is a tick-borne, infectious disease caused by Anaplasma phagocytophilum, an obligate intracellular bacterium that is typically transmitted to humans by ticks of the Ixodes ricinus species complex, including Ixodes scapularis and Ixodes pacificus in North America. These ticks also transmit Lyme disease and other tick-borne diseases.
Human monocytotropic ehrlichiosis (HME) is a form of ehrlichiosis associated with Ehrlichia chaffeensis. This bacterium is an obligate intracellular pathogen affecting monocytes and macrophages.
Ehrlichiosis ewingii infection is an infectious disease caused by an intracellular bacteria, Ehrlichia ewingii. The infection is transmitted to humans by the tick, Amblyomma americanum. This tick can also transmit Ehrlichia chaffeensis, the bacteria that causes human monocytic ehrlichiosis (HME).
Huaiyangshan banyangvirus, formerly SFTS virus, is a tick-borne Banyangvirus in the order Bunyavirales. It appears to be more closely related to the Uukuniemi virus serogroup than to the Sandfly fever group. It is a member of the Bhanja virus serocomplex.
The Lone Star virus is a highly divergent Bunyavirus, which is carried and transmitted by the Lone Star Tick, Amblyomma americanum. This is the same vector that transmits the SFTS virus, and the newly discovered Bhanja and Heartland virus.
Batai virus (BATV) is a RNA virus belonging to order Bunyavirales, genus Orthobunyavirus.
Bourbon virus is an RNA virus in the genus Thogotovirus of the family Orthomyxoviridae, which is similar to Dhori virus and Batken virus. It was first identified in 2014 in a man from Bourbon County, Kansas, United States, who died after being bitten by ticks. The case is the eighth report of human disease associated with a thogotovirus globally, and the first in the Western hemisphere. As of May 2015, a case was discovered in Stillwater, Oklahoma and relatively little is known about the virus. No specific treatment or vaccine is available. The virus is suspected to be transmitted by ticks or insects, and avoidance of bites is recommended to reduce risk of infection. In June 2017 a 58-year-old female Missouri State Park employee died from an infection of the Bourbon virus after it had been misdiagnosed for a significant period of time.
Heartland banyangvirus: derived from Heartland virus (and genus Banyangvirus)