Roundworms are parasites that infect humans. When an infected person defecates outside, eggs in their faeces become larvae that can enter the body if a person gets them on their hands and transfers them to the mouth. Once in the body, the larvae enter the lungs and throat and are later coughed up and swallowed. Roundworms cause cough, abdominal pain, diarrhoea, blood in stool and worms in vomit or stool. Routinely deworm children, use latrines and always wash hands before eating or handling food.
Attribution: Straight Talk Foundation