An orthohantavirus (or hantavirus) is a single-stranded, enveloped, negative-sense RNA virus in the Hantaviridae family of the order Bunyavirales. These viruses normally infect rodents, but do not cause disease in them. Humans may become infected with hantaviruses through contact with rodent urine, saliva, or feces. Some strains cause potentially fatal diseases in humans, such as hantavirus hemorrhagic fever with renal syndrome (HFRS), or hantavirus pulmonary syndrome (HPS), also known as hantavirus cardiopulmonary syndrome (HCPS), while others have not been associated with known human disease. HPS (HCPS) is a 'rare respiratory illness associated with the inhalation of aerosolized rodent excreta (urine and feces) contaminated by hantavirus particles.'Hantavirus An orthohantavirus (or hantavirus) is a single-stranded, enveloped, negative-sense RNA virus in the Hantaviridae family of the order Bunyavirales. These viruses normally infect rodents, but do not cause disease in them. Humans may become infected with hantaviruses through contact with rodent urine, saliva, or feces. Some strains cause potentially fatal diseases in humans, such as hantavirus hemorrhagic fever with renal syndrome (HFRS), or hantavirus pulmonary syndrome (HPS), also known as hantavirus cardiopulmonary syndrome (HCPS), while others have not been associated with known human disease. HPS (HCPS) is a 'rare respiratory illness associated with the inhalation of aerosolized rodent excreta (urine and feces) contaminated by hantavirus particles.' Human infections of hantaviruses have almost entirely been linked to human contact with rodent excrement; however, in 2005 and 2019, human-to-human transmission of the Andes virus was reported in South America. Hantavirus is named for the Hantan River area in South Korea where an early outbreak was observed, and was isolated in 1976 by Ho-Wang Lee. Hemorrhagic fever with renal syndrome (HFRS) is a group of clinically similar illnesses caused by species of hantaviruses from the family Hantaviridae. It is also known as Korean hemorrhagic fever, epidemic hemorrhagic fever, and nephropathia epidemica. The species that cause HFRS include Hantaan, Dobrava-Belgrade, Saaremaa, Seoul, and Puumala. It is found in Europe, Asia, and Africa. In hantavirus-induced hemorrhagic fever incubation time is two to four weeks in humans before symptoms develop. Their severity depends on the viral load. Hantavirus pulmonary syndrome (HPS) is found in North, Central and South America. It is an often fatal pulmonary disease. In the United States, the causative agent is the Sin Nombre virus carried by deer mice. Prodromal symptoms include flu-like symptoms such as fever, cough, muscle pain, headache, and lethargy. It is characterized by a sudden onset of shortness of breath with rapidly evolving pulmonary edema that is often fatal despite intervention with mechanical ventilation and potent diuretics. The fatality rate is 36%. Hantavirus pulmonary syndrome was first recognized during the 1993 outbreak in the Four Corners region of the southwestern United States. It was identified by Dr. Bruce Tempest. It was originally called 'Four Corners disease,' but the name was changed to 'Sin Nombre virus' after complaints by Native Americans that the name 'Four Corners' stigmatized the region. It has since been identified throughout the United States. Rodent control in and around the home remains the primary prevention strategy. Hantaviruses are bunyaviruses. The Bunyavirales order is divided into twelve families. Like all members of this order, hantaviruses have genomes comprising three negative-sense, single-stranded RNA segments, and so are classified as negative sense RNA viruses. Members of other Bunyavirales families are generally arthropod-borne viruses, but hantaviruses are thought to be transmitted to humans mainly through inhalation of aerosolized rodent excreta, or rodent bites. Like other members of Bunyavirales, orthohantaviruses are enveloped viruses with a genome that consists of three single-stranded, negative-sense RNA segments designated S (small), M (medium), and L (large). The S RNA encodes the nucleocapsid (N) protein. The M RNA encodes a polyprotein that is cotranslationally cleaved to yield the envelope glycoproteins Gn (formerly G1) and Gc (formerly G2).