II.

Hantaan Virus

The first human disease known to be due to a hantavirus infection was hemorrhagic fever with renal syndrome, identified in the early 1950s during the Korean War. Thousands of United Nations troops developed a mysterious disease marked by fever, headache, hemorrhage, and acute kidney failure. Despite much research, the cause remained unknown for 26 years until a new virus, named Hantaan virus, was isolated in Korea from field mice in 1976.

Hemorrhagic fever with renal syndrome is widespread in the Far East, particularly in China and Korea. There are two seasonal disease peaks, associated with the harvesting of wheat in summer and of rice in late fall. During these times the host rodent populations peak and the fields are full of dust containing dried, virus-laden excrement. The disease is fatal in about 5 to 10 percent of cases. A milder form of the disease, caused by Seoul virus and transmitted by rats, occurs in Japan, Korea, China, and the United States, especially in seaports, where rats are common. Symptoms are less severe and include nephritis (inflammation of the kidneys).