Hantaan virus

The genome of Hantaan virus is about 11.8 thousand nucleotides in length and segmented into three negative-sense, single-stranded RNA (-ssRNA) strands. The segments form into circles via non-covalent bonding of the ends of the genome. ==Structure==

Virions are mostly spherical or pleomorphic in shape and range from 80 to 160 nm in diameter. They contain a lipid envelope covered in spike proteins made of the two viral glycoproteins, Gn and Gc. The spike proteins extend about 10 nm out from the surface and are tetrameric, consisting of four copies each of Gn and Gc with helical symmetry, in which Gn forms the stalk of the spike and Gc the head. Spikes are arranged on the surface in a lattice pattern. Inside the envelope are the three genome segments, which are encased in nucleoproteins to form a ribonucleoprotein (RNP) complex. Attached to each RNP complex is a copy of RdRp. ==Life cycle==

HTNV primarily infects endothelial cells and macrophages. For replication of the genome, a complementary positive-sense strand is produced by RdRp. Copies of the genome are made from this complementary strand. Progeny RNA strands are then encapsidated by nucleoproteins. ==Evolution==

The most common way that hantaviruses evolve is through mutations of individual nucleotides being inserted, deleted, or substituted. Because Hantaan virus has a segmented genome, it is possible for recombination and reassortment of segments to occur, whereby segments from different lineages mix in a single host cell and produce hybrid progeny. ==Ecology==

Hantaan virus is transmitted by striped field mice (Apodemus agrarius). These mice mainly reside in rural areas, where they frequently use crop fields as a source of food. Antibodies to Hantaan virus have been detected in cattle, deer, and rabbits, but the role of these animals as hosts is unknown. Transmission to humans occurs mainly through the inhalation of aerosols that contain rat saliva, urine, or feces. Transmission can also occur through consumption of contaminated food, bites, and scratches. Infections with Hantaan virus mainly occur in rural settings such as in residences near crop fields or in such fields. In China, cases most commonly occur during the autumn harvest season when farmers work on and sometimes sleep in crop fields. ==Disease==

Hantaan virus infection can cause hemorrhagic fever with renal syndrome (HFRS). Symptoms usually occur 12–16 days after exposure and come in five phases: fever, hypotension, low urine production, high urine production, then recovery. The disease is hallmarked by acute kidney disease with kidney swelling, excess protein in urine, and blood in urine. Early symptoms include fever, headache, lower back pain, nausea, vomiting, diarrhea, bloody stool, and the appearance of spots on the skin. During the hypotensive phase, there is a sudden lowering of blood pressure and shock due to microvascular leakage. Low urine production then occurs as a result of renal failure. As renal function recovers, urine production increases. In more mild cases, the different phases of illness may be hard to distinguish, or some phases may be absent, while in more severe cases, the phases may overlap. but also in Russia and Vietnam. Avoiding or minimizing contact with rodents is key to prevent infection. In China and South Korea, bivalent vaccines for Seoul virus and Hantaan virus are available for use. ==Classification==

Hantaan virus is classified into the species Orthohantavirus hantanense in the genus Orthohantavirus, which is in the family Hantaviridae, the family that all hantaviruses belong to. Other members of Orthohantavirus hantanense include Amur virus and Soochong virus. The 76-118 isolate of Hantaan virus is the exemplar virus of the species. This taxonomy is shown hereafter: • Family: Hantaviridae • Genus: Orthohantavirus • Species: Orthohantavirus hantanense • Amur virus • Hantaan virus • Soochong virus ==History==

During the Korean War, around 3,200 cases of epidemic disease occurred from 1951 to 1954 among United Nations soldiers stationed near the Hantan river in northern South Korea. showed that antigens taken from the lungs of striped field mice were reactive to antibodies from sera of people who had Korean hemorrhagic fever. The virus couldn't be isolated in 1976 but testing showed that an infectious agent was responsible. It has undergone a series of changes to its species name, first changing to Hantaan hantanavirus, then Hantaan orthohantavirus, and most recently to the current Orthohantavirus hantanense. In 1989, the method to diagnose Hantaan virus infection was developed by Lee and just a year later he developed a vaccine against it, which made him the first person in history to discover the cause of a viral disease, develop a method to diagnose it, and develop a vaccine against it. ==References==