What is the primary reservoir for Shigella bacteria?

The primary reservoir for Shigella bacteria is indeed the human intestines. Shigella is a genus of bacteria that is specifically adapted to the human digestive tract, making humans the primary hosts. The bacteria are typically transmitted from person to person through the fecal-oral route, often occurring in environments where hygiene practices are inadequate, such as crowded living conditions or improper sanitation. Infected individuals can shed the bacteria in their feces, contaminating surfaces, food, and water, which highlights the importance of proper hygiene to prevent the spread of the infection.

While Shigella can survive in water to a certain extent, the bacteria do not have a natural reservoir outside of humans, which makes the human intestines the key source of Shigella outbreaks.