Pathophysiology of Enteric Fever is shown below in the cycle of usual infection transmission. Salmonella paratyphi may produce ulceration lower down in the intestines and these organisms pass through the feces resulting in contamination of the water and food supply by carriers or flies which are the usual transmission of infection.
The mostly cause of enteric fever, Salmonella typhi, enters the lymphoid follicles and affects the ileum (particularly lower part). If necrosis and ulceration happened, the mesenteric lymph nodes become infected and the salmonella invades the bloodstream via the thoracic duct. This conditions called bacteremia which could be happened up to the fourth week. Now, the bone marrow, spleen, kidney, liver, and gallbladder may become infected and the gallbladder may re-infect the intestines causing further acute inflammation of the lymphoid follicles.
Or you may download the complete Pathophysiology of Enteric Fever Transmission, here: http://www.psmid.org.ph/vol9/vol9num2topic4.pdf
(source: psmid.org.ph)
