Anatomical Detectable Tuberculosis in Victims of Unnatural Death in Kyoto and Mathematical Considerations of the Frequency of Tuberculous Primary Infection and Exogenous Reinfection

Abstract

(1) Tuberculous lesions were detected by pathological-anatomical studies in the victims of unnatural death in Kyoto city at the rate of 38% in childhood (from birth to 14 years old), at 58% in the adolescent age-group (from 15 to 19 years old) and at 82% in adult and advanced ages (20 years and over). According to studies on the properties of the primary complex of anatomical tuberculosis primary infections in the adult and advanced age groups are apparently not rare in Japan, but occur usually at the same or even greater frequency than in chidhood and adolescence. (2) The positive rate of total individuals who have experienced primary infection during (n) years after birth under the definite infection rate per year (a) is given by the formula P_n (a)=1-(1-a) From the results of anatomical tuberculosis and tuberculin test in Kyoto city it is induced that the rate of infection with tuberculosis per year among the popultion in Kyoto city is about 1/20. While the rate of infection with tuberculosis per year in a typical and semi-rural district (Oomi-Hachiman town and neighbours) in Japan is apparently about 1/50 or less, (3) The positive rate of total individuals at (n) years old in population, who had chances of exogenous reinfection more than twice during (n) years after birth under definite infection rate per years (a), given by the following mathematical formula; R_n (a)=1-(1-a)^n(1+na). By calculation of this mathematical formula it can be deduced that the total individuals, who had chances of exogenous reinfection or superinfection more than twice, appear even during adolescence and they increase strikingly in the advanced age-groups under conditions in which tuberculosis can be widly spread as has been noticed in large cities in U.S.A. and Europe in the past, where the dangerous rate of infection per years is deduced to be about 1/10 or 1/15. But it is ordinarily low even in the adult and advanced age-groups in the rural or semi-rural district. s, where the rate of infection per year is very small (1/50 or below it.)