The Results of Tuberculin testing in Korea
Authors: Kim Hyun Kyu 
Published: March 2022

The tuberculin test is the simplest and the best method at hand for determining wheter a host has been infected with tuberculin bacilli. The test is important before vaccination, in order to rule out previous virulentinfection, therefore almost of these investigations were conducted prior to vaccination under the close cooperation with the United Nations Korean Reconstructions Agency from January, 1952. The old tuberculin routinely used in these investigations were prepared by the National Institute of Health, Seoul, Korea and the Japan Antituberculosis Association as follows.Through the investigation the reading method initiated by prof. T. Toda, in Japan was employed. Following results were obtained from the investigation conducted over 559,440 pupils who were injected with 2 ,000:1 O.T. (5 T.U., Old tuberculin) from 1948 to 1959 in Korea.1) Of the institutions investigated, the prison showed the highest pre-vaccination tuberculin positive rate (96.06%) and institutions which are lived in collectively showed higher percent than other groups. i.e. Mine>College>Spimnery>Army etc(See Fig.1) 2) By province, Seoul special city showed the highest pre-vaccinations tuberculin rate in primary schools(53.27%), and provinces that surround Seoul city showed next to the highest for example, Chung Chong Book Do<Kyung Ki Do>Kang Won Do are higher than others, and Kyung Sang Book do was the lowest in the rate(33.99%). (See Fig.2)3) By cities and towns, Masan showed the highest pre-vaccination tuberculin rate in primary schools(54.31%). Several sanatorum are located in the city of Masan. Cities and towns which have not been rehabilitated completely from the damages brought by the Korean war,(for example, ChunChon>Seoul>YongWol>InChon etc)are higher than other. And Ook-Koo is the lowest(33.34%) in the rate.(See Fig.3)4) Pre-vaccination tuberculin positive rate by school years in Seoul primary school was the highest at sixth class, and with an increase of one school year, it steps up at 3-4%. And every higher age group in years showed higher percent than lower age group.(See Fig.4)5) By school years, refugee primary schools in six large cities showed about 11.0 percent higher pre-vaccination tuberculin positive rate than indigenous schools, and while in an indigenous school, the rate increases at 3% with an increase of one school year, it does at 4% in a refugee school.(See Fig.6)6) By age, refugee schools showed about 10 percent higher rate than indigenous school in the same age group, and the rate increases with age. (See Fig.7)7) Tuberculin positive rates averaged 38.68% in kindergarten, 47.76% in orphanage and 38.54% in the refugee camp.(See Fig.8)8) Tuberculin positive rates averaged 6t5.93% in middle school, 75.14% in high school. The refugee middle schools and high schools showed 7.93% and 5.34% respectively higher rate than the indigenous middle schools and high schools. This indicates that the younger their age are, the more different there in corresponding of the rates between the group of refugee students and that of the indigenous students, of the same age. i.e. primary school>middle school>high school(11.04%: 7...95%: 5.34%)(See Fig.9)9) Younger age groups in years showed higher tuberculin positive rate than older age groups.(See Fig.10)10) There are no specific differences in the percentage of the tuberculin positive rate between male and female.(See Fig.11)11) 10-20% of the age groups under 30 showed speaker positivein tuverculin reaction. However among the strong positive groups, under the 15 years age showed 25-30 positive. After 15 years of age the percentage rate increases with increasing age and at 30 years of age, the positive rate reached 54%.(See Fig.12)12) Refugee primary schools in whole country showed higher tuberculin positive rate(about 3.91%) than Seoul primary schools and about 11-12% higher than indigenous primary schools.(See Fig.13)13) All alike in the kindergarten, orphanage, primary school, middle school and college, the tuberculin positive rate increased after the Korean war.(See Fig. 14)14) Children in contact groups showed higher tuberculin positive rate than non contact groups i.e. about 30.0% higher ati 6months after birth, and at one year showed tuberculin positive ratio 43.5%: 5.1% between these two groups. And the differences of the ratio between these two groups decrease with increasing age.(See Fig.15-16)15) No yearly changes in tuberculin positive rate have been observed during the period of 1949, 1952 and 1953. From 1954, the rate tended to increase, although in didn't necessarily step up with regularity.(See Fig. 17)16) Through out he country, older age groups showed higher tuberculin positive rate than younger age groups, and the rate was abut 32% at the 0-4 age groups.(See Fig.18)17) Through the comparison between Korean old tuberculin and Japanese old tuberculin, which were used in 1952, the following results were observed.18) Blister and necrosis were observed after injection with either Korea. O.T. or Japanese O.T. as follows without any other complications.i.e.19) Among the negative reaction to 1:2, dilution tuberculin, 3.7% showed daubtful positive and 4.5% showed definite positive with 1:500 dilution tuberculin.(See Table 4)20) Korean O.T. are equally as strong as the standard O.T., and Japanese O.T. and P.P.D.S(standard P.P.D.) are weaker than standard O.T.(about 1/2×standard O.T.), RT22*danish P.P.D.)is much weaker than standard O.T.(about 1/4×standard O.T.) on the BCG vaccinated guinea pigs.(See Table.5-6)21) The results of tuberculin testing in Korea which was carried out in 1952 showed all positive in pre-vaccination tuberculin reaction. It is believed that the natural infection rate of tuberculosis in this country could be estimated with these data herein presented.