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 caused by virulent bacteria called Salmonella typhi (S. typhi). Although they're related, S. typhi and the bacteria responsible for salmonellosis, another serious intestinal infection, aren't the same.ecal-oral transmission route. The bacteria that cause typhoid fever spread through contaminated food or water and occasionally through direct contact with someone who is infected.