Symptoms are likely to start slowly, often showing up 1 to 3 weeks after exposure to the bacteria. Early illness Early symptoms include: 
Fever that starts low and increases throughout the day, possibly reaching as high as 104 degrees Fahrenheit (40 degrees Celsius).
Chills.
Headache.
Weakness and fatigue.
Muscle aches.
Stomach pain.
Diarrhea or constipation.
Rash.
 People also may have a cough, loss of appetite and sweating. Later illness A few weeks after symptoms start, the illness can cause problems in the intestines. People may have: 
Stomach pain.
Very swollen stomach.
An infection caused by gut bacteria spreading throughout the body, called sepsis.
 In very serious cases, people may: 
Become confused.
Not be able to pay attention to anything around them.
Not be able to react to the world around them.
 These are life-threatening complications. In some people, symptoms may return up to a few weeks after the fever has gone away.