TUBERCULOUS INFECTION IN THE LIGHT OF TUBERCULIN MATRICULATION12

Abstract

Tuberculin matriculation (continuous tuberculin testing of a whole population) is recommended as the best method of diagnosis and control of tuberculosis in regions or populations with low infection rates. The present work summarizes the results of an 8-yr. study (1937-1944) of a Norwegian community of 6500 inhabitants (25% urban, 75% rural) in which repeated tuberculin tests were made on a large proportion of the entire population. The von Pirquet test was used and tests were made with Norwegian or Danish tuberculin, with and without epinephrine. A good discussion of tuberculin test technics is given. In town 20% of both sexes were infected on reaching adolescence. After 30 yrs. of age 70% of the males and 55% of the females were found to be infected. In the country 13% were infected on reaching adolescence. After 30 yrs. of age 45% were found to be infected. Primary infection seems to occur in late childhood and early adult life. 274 converters (tuberculin test) were found (56 from 1937-40 and 218 from 1941-44) of which 28% were in children under 14, 57% in young adults 15-29, and 15% in adults over 30 years of age; of the converters found 48% were proved to have "tuberculous disease" and 13% were doubtful. Of those having tuberculous disease the infection appeared soon after exposure and the incidence was greatest in the younger age groups. By finding cases with the use of tuberculin matriculation much epidemiological information is obtained. Examples are cited. In intradomiciliary infections brother and sister contacts are most important and in extradomiciliary infections companions and neighbors are important. Primary infections were found not to be infectious as were progressive cases. A good discussion on the forms of tuberculosis and the progression of infection is given. The author believes tuberculin is better than mass radiography for screening. In part this belief is due to lack of facilities for radiography. He does not recommend BCG because it makes diagnosis (tuberculin matriculation) difficult. There was a steady decline in tuberculosis in the community during the study.