The sixth Nationwide Tuberculosis Prevalence Survey in Korea, 1990.

SETTING

Nationwide random sample survey for tuberculosis in 1990.

OBJECTIVE

To investigate the prevalence of tuberculosis infection, morbidity and drug resistance and BCG coverage, and to compare the findings with those of the previous 5 surveys.

DESIGN

The following investigations were performed: tuberculin test, BCG scar screening, chest miniature radiography (70 mm x 70 mm) for those aged over 5 years, sputum direct smear, culture and drug susceptibility test, and a questionnaire to obtain history of chemotherapy and symptoms.

RESULTS

The coverage of the investigation has been of more than 95% in each survey. The main findings are as follows: BCG coverage of those aged under 30 and of infants (aged under 1 year) has increased from 24% to 86% and from 1% to 79% respectively. The observed tuberculin positivity (> or = 10 mm in diameter) of subjects aged under 30 has decreased from 45% to 27%. The reduction of positivity was significant in children aged 5-9 years, from 34% to 8%. The annual risk of infection has dropped by over 6% annually. The prevalence of pulmonary tuberculosis per 100,000 has decreased: direct smear-positive from 690-143, smear and/or culture positive from 940-241 and active cases from 5065-1842 respectively. The drug resistance rate had increased to the peak of 47% in 1980, but had decreased to 27% in the last survey.

CONCLUSION

The tuberculosis situation has improved significantly in every aspect in the last 25 years.