In 1978, the etiologic agent of Korean Hemerologic fever was isolated from small infected field rodent Apodemus agrarius near Hantan river in South Korea. The virus was named as Hantaan virus, after the name of the river Hantan. This initial discovery dates back to scientific approaches that were initiated after the Korean war (1951-1953), during which more than 3000 cases of Korean hemorrhagic fever were reported among United Nations (UN) troops.

In 1981, a new genus termed as “hantavirus” was introduced in the Bunyaviridae family, which included the viruses that cause hemoroligic fever with renal syndrome (HFRS). It was initially thought that pathogenic hantaviruses are restricted to old word. Until 1993, the only native hantavirus found in new word was non pathogenic Prospect Hill virus (PHV). This myth ended after the hantavirus outbreak in the four corner region of Southwestern United States that caused serious respiratory distress in infected patients and lead to the discovery of a new hantavirus disease called hantavirus cardiopulmonary syndrome (HPS).

An examination of frozen stored samples of lung tissue from people who had died of unexplained lung disease in the past revealed that HPS is an old disease with conformed cases dating to at least 1959. Within a very short period the virus causing HPS was isolated from common dear mouse (Peromyscus maniculatus,) and was later named as Sin Nombre virus (SNV). Later on, it became clear that other hantaviruses similar to SNV, such as Andes virus (ANDV), are present through out the united states. Currently, the hantavirus genus includes more than twenty one species and more than 30 genotypes. Hantaviruses have coevolved for millions of years with their rodent and insectivore reservoirs.

As described by the Centers for Disease Control and Prevention (CDC), Patients with HCPS typically present a short febrile prodrome of 3-5 days. In addition to fever and myalgias, early symptoms include headache, chills, dizziness, non-productive cough, nausea, vomiting, and other gastrointestinal symptoms. Malaise, diarrhea, and lightheadedness are reported by approximately half of all patients, with less frequent reports of arthralgias, back pain, and abdominal pain. Patients may report shortness of breath, (respiratory rate usually 26 – 30 times per minute).

During 1993 hantavirus outbreak, cross-reactive antibodies to the previously known hantaviruses, such as, Hantaan, Seoul, Puumala, and Prospect Hill virus were found in the acute- and convalescent-phase sera of some HPS patients. Since then, tests based on specific viral antigens from SNV have been developed and are widely used for the routine diagnosis of HPS. Enzyme-linked immunosorbent assay (ELISA) is the popular test for the detection of IgM antibodies in patient’s blood that are raised against Hantaviruses during infection.