Abstract
The difficulties of diagnosis in the early cases of epidemic hemorrhagic fever in Korea are described. The clinical picture resembled that seen by the Japanese during similar epidemics in their troops in Manchuria (1939-1941). Japanese workers believe the disease is due to a virus maintained in the field rodent Apodemus agrarius and transmitted to humans by the bite of the mite Laelaps jettmari. The Korean epidemic had one peak in July, 1951, and a 2d larger one in Oct. The fatality rate in the 1st peak was 13-18%. Person-to-person spread did not occur. All attempts to transmit the disease to exptl. animals failed. It was not possible to demonstrate whether the disease had been recently introduced into Korea or had existed previously unrecognized.