伤寒患者及带菌者是伤寒的传染源。在伤塞发病率鞍低的地区,伤塞带菌者是伤寒的主要传染源,而慢性伤寒带菌者的传播作用尤为重要。有些地区居民中慢性伤寒带菌者约占居民的0.1～0.3%,估计居民中的伤寒带菌者多于伤寒患者数倍至数十倍,而慢性伤寒带菌者的传染期可长达数年至数十年 Merselis 氏。检验伤寒带 Typhoid patients and carriers are sources of typhoid fever. In regions with a low incidence of sedentary injuries, wounded carriers are the main sources of typhoid fever, and the transmission of chronic typhoid carriers is of particular importance. Chronic typhoid carriers in some areas account for about 0.1 ~ 0.3% of residents. It is estimated that typhoid carriers among residents are several times to several ten times more than typhoid patients, while the infection period of chronic typhoid carriers can be up to several years Ten years Merselis’s. Check the typhoid zone