Report of Nationwide Epidemiology of Aseptic Meningitis Outbreak in 1993 in Korea

Oh, Sung Hee; Lee, Moo Song; Kang, Jin Han; Kim, Chang Hwi; Park, Chong Young; Sohn, Young Mo; Lee, Hoan Jong; Chun, Chung Sik; Shin, Sang Mann

Abstract

PURPOSE: There has been no nationwide report pertaining to the epidemiology of aseptic meningitis, although a great numer of patients have been diagnosed of the illness. Therefore, we report an explosive outbreak of aseptic meningitis occured in a nationwide scale in 1993.
METHODS
Aseptic meningitis epidemiology surveillence was performed retrospectively on the patients diagnosed of aseptic meinigitis from January 1993 to December 1993 at 60 hospitals (the third graded medical centers and comparable training hospitals) located in 9 districts. The data pertaining to the patients were obtained through the questionnaire answered by the pediatricians or pediatric houseofficers. Monthly and geographical distributions, age and sex distributions, clinical manifestations, laboratory data, complications, and the causative virus of aseptic meningitis were described.
RESULTS
1) The total number of cases reported in 1993 aseptic meningitis epidemiology surveillence was 5,090. Geographically the greatest number of patients was reported from Seoul (2,693), followed by Kyungnam (851), Chunbook (497), Kyungi (492), Chungnam (189), Kangwon (133), Kyungbook (127), Chunnam (82), and Cheju (26). 2) Monthly distribution revealed that the number of patients was increased from April to August and 95.4% (4,858 cases) of the totoal were diagnosed from May to July. The median dates for the diagnosis of aseptic meningitis in various districts were May 8 in Cheju, followed by Chunbook, Kyungnam, Chunnam, Kyungbook, Chungnam, Kyungi, Seoul in June and July 3 in Kangwon. 3) Average age of the study population was 4.7+/-2.9 years and male to female ratio 2.1:1. 4) Subjective symptoms consisted of headache, abdominal pain, poor appetite, irritability, etc, and physical findings fever, local neurological signs, etc in order of frequency. Duration of temperature elevation was 6.1+/-3.7 days in average and 22 cases had no temperature elevation at all. 5) Initial CSF findings revealed pressure of 132 66 mmH2O, leukocytes 594+/-890/mm3 with PMNL 25.6+/-24.7% and lymphocytes 72.3+/-26.1%, protein 47.0+/-37.6 mg/dl, and glucose 60.3+/-14.9 mg/dl. In 35.7% of the patients, CSF leukocytes were more than 500/mm3 and in 19.9% were greater than 1000/mm3. Thirty five patients did not have pleocytosis in the initial CSF examination. 6) The associated illnesses were pharyngotonsillitis (1,285 cases, 31.3%), pneumonia (104 cases, 2.7%), sinusitis (74 cases, 1.9%), etc. 7) While almost all the patients (99.0%) were reported to be improved without complications, 48 cases had complications with 7 encephalitis, 2 neurogenic bladder, 2 Guillian-Barr syndrome, 5 paralysis, and 32 unspecified. Six cases were reported to be deceased. 8) Virus was isolated from 25 out of 55 cases from Seoul and Kyungnam areas on whom virus isolation was tried, and all were echovirus 9.
CONCLUSIONS
Aseptic meningitis outbreak in 1993 was nationwide, geographically begun in the southern part of the peninsula spreading rapidly northward, and seasonally occurred from April to August with the peak in June. The average age was 4.7+/-.9 years and male to female ratio 2.1:1. Clinical manifestations and laboratory findings of the study patients were comparable to the reported previoulsy. The causative virus for the nationwide aseptic meningitis outbreak in 1993 was echovirus 9.