Studies on the carrier-state of haemolytic streptococci in iron-masters.

Throat swabs from 165 iron-masters and 160 control subjects were tested for the presence of group A, C and G haemolytic streptococci and other serological groups. The group-A streptococcus strains were serotyped. The study was extended to the evaluation of the state of health, analysis of the sanitary conditions at the working place as well as the analysis of the social, living and economic conditions. Carriers of group-A haemolytic streptococci were of approximately the same frequency in healthy iron-masters and healthy controls and the proportions of the carriers of streptococci of other serological groups were also comparable. On the other hand, some differences in the proportions of the carriers of groups A, C and G haemolytic streptococci in persons with respiratory tract disorders were found, affected iron-masters comprising twice as many carriers as affected controls. The differences are attributed to the different sanitary-hygienic conditions at the working places.