Whipple's disease is a rare bacterial infection that primarily affects the small intestine. It is not considered contagious and does not spread from person to person. The bacteria responsible for Whipple's disease, called Tropheryma whipplei, is typically acquired from the environment. It is important to note that while the disease itself is not contagious, the bacteria can be present in the stool of infected individuals, so proper hygiene measures should be followed to prevent its transmission.