The parasite can then invade the colon, causing it to become inflamed. The illness may produce no symptoms at all, or may produce only very mild ones. Direct transmission of amebiasis occurs through contact with infected stool. The infection is also a sexually transmitted disease , particularly among male homosexuals. Fruits and vegetables can be contaminated when they are grown in soil fertilized by human stool, washed in polluted water, or prepared by someone who is infected.
Amebiasis is more common and more severe in subtropical and tropical areas.
It occurs more often when living conditions are crowded, sanitation is poor, and nutrition is inadequate. A person should eat only food that is unlikely to be contaminated, especially when traveling to tropical regions. This means keeping to food that is well cooked and water that is bottled. Practicing safer sex will also help prevent the spread of amebiasis. Amebiasis is usually identified by examining the stool.