This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
Shigellosis is a disease caused by a group of bacteria called Shigella. Shigella is very contagious. Shigella germs are present in the stools of infected individuals for up to two weeks after symptoms have resolved. Individuals may be exposed through direct contact with an infected person or through contaminated food, water (both drinking and recreational water), or surfaces. Though anyone can get shigellosis, young children are most at risk. Symptoms of shigellosis usually begin one to two days after exposure and include diarrhea, abdominal pain, and fever. In otherwise healthy individuals, the symptoms usually resolve in 5-7 days. Those with mild shigellosis may need only rest and self-care measures to avoid dehydration (drinking fluids and electrolyte solutions). For more severe cases, antibiotics may be prescribed though some cases of shigellosis have been found to be resistant to antibiotics. Laboratory tests can be performed to determine which antibiotics are likely to be effective in an individual case. Most people make a full recovery, though it may take several months for bowel habits to return to normal. Complications are rare but may include post-infectious arthritis, bloodstream infections, seizures, or hemolytic-uremic syndrome (HUS). 
For more information, visit GARD.