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.
Typhoid fever is a bacterial infection that can spread throughout the body, affecting many organs. Without prompt treatment, it can cause serious complications and can be fatal. It's caused by a bacterium called Salmonella typhi, which is related to the bacteria that cause salmonella food poisoning.Typhoid fever is highly contagious. An infected person can pass the bacteria out of their body in their stools (faeces) or, less commonly, in their urine.t's caused by a bacterium called Salmonella typhi, which is related to the bacteria that cause salmonella food poisoning. Typhoid fever is highly contagious. An infected person can pass the bacteria out of their body in their stools (faeces) or, less commonly, in their urine.