blood in stool

Overview

Dysentery is an infection in your intestines that causes bloody diarrhea. It can be caused by a parasite or bacteria.

Dysentery Causes

What type you have depends on what caused your infection.
Bacillary dysentery is the most common type of dysentery. It results from bacteria called Shigella. The disease is called shigellosis. About 500,000 people in the U.S. get it every year.
Amoebic dysentery comes from a parasite called Entamoeba histolytica. You're more likely to get this kind of dysentery if you travel to a tropical location that doesn’t have good sanitation.
You can get dysentery if you eat food that's been prepared by someone who has it. For example, you might get it if the person who made your food is sick and didn't properly wash their hands. Or you can get dysentery if you touch something that has the parasite or bacteria on it, such as a toilet handle or sink knob. 
Swimming in contaminated water, such as lakes or pools, is another way you might catch dysentery. JPeei clinic
You can sometimes carry the bug that causes dysentery for weeks or years without knowing it. You can still pass the infection to other people, even if you don't have symptoms.

Dysentery Symptoms

Symptoms can show up 1-3 days after you get infected. In some people, the symptoms take longer to appear. Others never get symptoms.