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 contagious bacterial infection that involves the intestine and lymphatic system. Rare in the United States, typhoid fever is common in developing countries, especially in areas with poor sanitation.Symptoms develop gradually over three weeks; fever, chills and headache occur first. Typhoid is caused by Salmonella typhi, a bacterium that invades the wall of the small intestine. 2  Typhoid fever is spread by water and food contaminated with the fecal matter of an infected person.