An Epidemiological and Pathogenological Study on Dysentery and Enteritis

Abstract

The morbidity rate of dysentery which demonstrated a figure of 154. 6 in 1951 decreased gradually to 42. 5 in 1959.
The mortality rate which was as high as 41. 3 in 1949 was gradually lowered to 2. 8 in 1956 and to 4. 9 in 1957, however, elevated again to 13. 7 in 1959.
Healthy carriers of dysentery bacilli were found in 1. 2% in 1956, in 1. 4% in 1957, in 2. 3% in 1958 and 3. 0% in 1959, indicating a gradual increase.
The epidemic types of dysentery bacilli from 1956 to 1959 were Sh. flexneri la (1. 5%), lb (3. 6%), 2a (19. 090), 2b (25. 6%), 3a (20. 2%), 4a (2. 6%), var. X (1. 0%), var. Y (0. 5%), Sh. boydii 2 (0. 5%) and Sh. sonnei (16. 5%), so that Sh. flex. 2 played a major role, however, in 1959 Sh. flex. 3a and Sh. sonnei demonstrated an increase.
S. posdam and S. tennessee were isolated from 2 infants suffering from “Ekiri ” syndrome. E. coli 0-143 was isolated from an adult patient suffering from dysenterylike symptoms.
The majority of dysentery bacilli isolated demonstrated positive quinone reaction, whereas 82. 5% of Sh. flex. 3a and 21. 9% of Sh. sonnei proved negative.
A relationship was found between the sulphathyasol-sensitivity and the quinonereaction, i. e. 80.7% of Sh. flex. 3a and 34.4% of Sh. sonnei were sulphathyasol-sensitive.
Most strains were sensitive against chloramphenicol, streptomycin and tetracycline. Seven resistant strains (8.9 %) were isolated for the first time in 1959 (78 strains).
The seven resistant strains were ; 2 against SM alone (2.5 %), 3 against TC (3.9 %) and 2 against all the three antibiotics (2.5%).