1 Blood clots can also obstruct veins, causing pain. 2  Veins return blood from the legs to the heart. 3  There are two systems of veins in the leg: superficial and deep. 4  If a blood clot occurs in a deep vein (deep venous thrombosis), it causes a damming effect, and blood is trapped behind the blockage.
Typhoid fever, also known simply as typhoid, is a symptomatic bacterial infection due to Salmonella typhi. Symptoms may vary from mild to severe and usually begin six to thirty days after exposure.
About... Typhoid Fever (Salmonella Typhi) What is typhoid fever? Typhoid fever is a life-threatening illness caused by the bacterium Salmonella Typhi, which is found in the stool of an infected person. Unlike other Salmonella bacteria, S. Typhi is not found in animals. Typhoid fever is extremely rare in the United States and is almost always related to travel to an area of. the world where typhoid fever is common, such as Asia, Africa, and Latin America.