1981 Volume 55 Issue 6 Pages 410-428
In the period from February 1976 to Jury 1978, epidemic hemorrhagic fever (EHF) developed in 7 doctors among the clinical staffs together with working at the experimental laboratory in Wakayama Medical College.
All instances were 20-40 year-old male doctors who had lived in Wakayama city, and admitted to our clinic of Wakayama Medical College. The patients were hospitalized from 4th to 8th day after onset and the duration of hospitalization varied from 7 to 78 days. Six patients suffered in spring or eary summer. From the clinical severity, the patients were divided into two groups, 3 severe cases and 4 mild or moderate cases.
Majority of the cases had an abrupt onset with high fever and chills, sometimes malaise and anorexia. The symptomes included high fever of 39-40°C, chills, malaise, anorexia, body aches, nausea, vomiting, sore throat, abdominal pain, diarrhea and oliguria. On admission physical examinations demonstrated injected pharynx, cervical lymphadenopathy, periorbital edema, purpura, abdominal tenderness and mild hepatomegaly. Within a few days after the duration of fever, severe cases revealedthe various signs including shock, heart murmur, enlargement of the heart, pulmonaly congestion, skin edema, ascites, atrial fibrillation, atrioventricular block, retention of pleuropericardial effusion, mental disturbance, tremor and abnormal sensorium.
Laboratory examinations showed marked proteinuria, leukocytosis (early leukopenia), an increase of atypical lymphocyte, thrombocytopenia and an elevation of serum GOT, GPT, LDH, CPK and α-HBDH activity, but serum bilirubin and alkaline phosphatase were not elevated. In severe cases a rise of BUN and creatinine, a decrease of serum total protein and the abnormality of serum electrolytes. These abnormalities reached a peak within about 7 days and return to normal within a few weeks. The degree of these laboratory data paralleled to the severity of the disease.
The instances in mild and in severe cases were clinically and biochemically recovered within about a week and within about two weeks respectively.
Immunofluorescent (IF) antibodies to Korean hemorrhagic fever (KHF) virus (Lee and Lee, 1976) were tested by Dr. H. W. Lee in convalescent sera of all 7 patients obtained during from 72 da ys to 54 months after recover. Six patients were positive and had the titers ranged 1/512-1/8192. Also IF antibodies were tested in sera of experimental animals which seemed to be the reservoier of EHF virus. They were at high rate positive only in rats. In 119 sera obtained from the staffs in contact with IF antibody-positive rat, 17 instances (include above 7 patients with EHF) were positive (14.3%). Eleven of 17 had a history of transitory fever, malaise, anorexia and other flu-like symptomes, and they were diagnosed as a common cold.
Finally it is considered that the characteristic clinical features and course of illness in outbreak 7 patients at Wakayama Medical College correspond to that of EHF (Ibuki, 1942), and serologically to KHF (Lee, 1979). Therefore the diagnosis of EHF was done on the ground of the clinical patt ern of the disease and comfirmed by demonstrating IF antibodies to KHF virus
