Epidemiologic Study during 1993 Measles Outbreaks in Seongnam Area

ABSTRACT

PURPOSE: Although remarkable progress has been made in efforts to control measles since measles vaccines became available for use, the longterm success of their vaccination programmes has been questioned, with the worldwide resurgence of the disease. This resurgence has increased attention on the inadequacy of current immunization programmes. In 1993 there have been measles outbreaks in Seong-nam city located near the sourthern Seoul, Korea. To characterize further the epidemiology of measles in Seong-nam city, we analysed demographic characteristics of measles cases reported for the year 1993. METHODS: With the cooperation of the nurse teacher in elimentary school, the data of measles cases were collected and each case was confirmed at local clinics, hospital or general hospital, including inha General Hospital. RESULTS: 1) Out of 645 cases(male female = 1.081) the children above 5 yrs of age were 586 cases of which 529 cases(90.3%) were vaccinated on after 15 months of age. After the survey, measles occurred in 1.9% of the 11 elementary school students. Children with past MMR vaccination history showed milder course of measles than those without the vaccination history. 2) Out of 87 patients who had been brought to Inha General Hospital, 55%(n=48) was 6 to 1 5 months of age, 13%(n=11) was 15 months to 4 years of age, and 32%(n=28) was 5 to 14 years of age, which showed two major outbreaks those in which of the cases occurred below 16 months of age and those in which considerable cases occurred among school-age persons. 3) Below 15 months of age, most of the cause of the unvaccination were inadequate access to medical care and lack of public awareness in some communities, with the resulting lack of d emand for immunization services. The causes of unvaccination above 15 months of age were neglect or oblivion in 35%(n=2 0), mild acute illness not contraindicated to vaccine use in 21%(n=12), economic difficulty in 8. 8%(n=5), vaccine omission after natural measles before 12 months of age in 7%(n=4). CONCLUSIONS: Despite the high uptake of measles vaccine there is currently a nationwide e pidemic of measles, especially among the school-age groups. Secondary vaccine failure is also thought to be important cause of measles ortbreak as well as primary vaccine failure. A booster dose of measles vaccine may be necessary to reduce the measles outbreak to allow the goal of measles elimination to be achieved, with the reinforcement of age-appropriate Immunization.