Epidemiology of bacillary dysentery in Algeria. II. The seasonality of dysentery

Morbidity rises during the period of summer and autumn are characteristic of bacterial dysentery in Algeria. During the last 18 years no essential changes in the seasonal character of bacterial dysentery were observed in the country taken as a whole. However, in different climatic and geographical zones of the country the seasonal character of dysentery greatly varies from one zone to another and essentially differs from the seasonal character of dysentery morbidity, typical of the country as a whole for many years. The most pronounced manifestations of seasonal rises are observed in the Sahara zone. The seasonal character of dysentery is formed mainly by morbidity among patients belonging to 3 age groups. The seasonal rises of dysentery can be probably explained by the complex of social and climatic factors, as well as by the biological features of the causative agents of this disease.