Primary and secondary schoolchildren in Hateruna, a small island of Ryukyu, were subjected to throat culture for hemolytic streptococci (HS) in March andJuly, 1971 to study the incidence of HS as a whole, group and type distribution, and the prevalence of rheumatic heart disease and nephritis. The results were compared with those obtained in primary and secondary schoolchildren in Fuchu districts in Tokyo by the same fashioned survey as above performed in June, 1969, 1970 and 1971, respectively. The incidence of HS as a whole was higher in Hateruna (60.8% and 43.7% in the two surveys, respectively), than in Fuchu (38.2%, 25.0% and 19.9% in the three surveys, respectively). The incidence of Group A streptococci was also higher in Hateruna (40.5% and 25.0%) than in Fuchu (15.2%, 19.2% and 19.9%). In typing of Group A streptococci by means of T-agglutination, it is interesting to see that the predominant type in Hateruna was T-11, while in Fuchu, likewise as the other various parts in Japan, it was T-12. Abnormally high serum anti-streptolysin 0 titer, that is, over 333 Todd Unit, was found in 3.7% in Hateruna, while in Fuchu, 10.0, % 6.8% and 15.7%. No patient with rheumatic heart disease was encountered in Hateruna, whereas, in Fuchu there found in 0.01%. Apparent nephtitis could not be found in Hateruna. From above results, it is suggestive that the possibility for HS to get pathogenicity to the school children in Hateruna is scarce, though the incidence of HS as a whole and A Group too was found higher there than in Tokyo. The high incidence of T-11 is worth mentioning, but, the role and character of it as pathogenic microorganisms could not be determined yet in this study.
The present study is based on the therapeutic trial of sulfamethoxazole (SMX)-trimethoprim (TMP) combination preparation in 266 cases of bacillary dysentery and its allied disorders and 18 cases of Salmonella infections. Results of in vitro bacteriological studies on SMX, TMP and its combination in organisms isolated from these patients are also included. The results of our study can be summarized as follows: 1. The efficacy of SMX-TMP combination preparation against bacillary dysentery and its allied disorders was similar to those antibiotics commonly employed in the treatment of these disorders. No difference was found in effective rate between the daily doses of 4 tablets and 6 tablets. 2. Fifty percents of the patients with typhoid fever were successfully controlled by this combination preparation. 3. Marked potentiation of in vitro antimicrobial activities was demonstrated by combining SMX with TMP (20: 1) in all 137 strains of Shigella and 65 strains of Salmonella isolated from the clinical materials.