Geography

• The disease only exists in specific parts of the world. It is considered endemic to Africa, Asia and a number of other specific areas. If you are not in those areas, your risk level is generally quite low.
  
  

Age

• Children are generally at a higher risk of contracting the disease. Adults are at a lower risk of contracting it. Children, however, have less serious symptoms than adults do.
  
  

Proximity

• Contact with another individual that is infected creates a higher level of risk. Medical professionals and other individuals that work with the general population in areas where typhoid is endemic will likely have a higher risk of becoming infected.
  
  

Water Considerations

• If you consume water that contains the bacteria S. typhi, your risk level is greatly elevated. This is the bacteria that causes typhoid fever. Other things, such as food, may contain S. typhi. Cooking reduces the viable amounts of the bacteria.
  
  

Warning

• Since typhoid fever is an infection, a healthy immune system can help to protect you if you are exposed. A reduced immune system, as in cases of individuals with HIV, may elevate your risk of infection.