Very heavy roundworms infestation may cause blockage and perforation of the intestine. This leads to the life threatening infection called peritonitis. Blockage of the pancreatic and bile ducts may also occur. To avoid this ! Avoid eating food prepared on road side and particularly stored near or on grass.
The life cycle of a roundworm [Ascaris lumbricoides] : The eggs are laid in the alimentary canal of host-human or animal-from where they pass out with the faeces. Once on the ground, the eggs hatch into larvae which latch onto grass. The animal or human swallows these larvae as it eats grass or eggs contaminated food in case of human.
Once the eggs have been ingested [swallowed] by the animal or human, they hatch into young worms which are referred to as juveniles. These juveniles migrate through the intestines into the bloodstream from where they move to the lungs. In the course of their movement, the juveniles mature into worms.
Once they are in the lungs, the worms move up the trachea where they are coughed and swallowed with sputum into the intestines. They mature into adults in the small intestines where they lay eggs and cycle begins again.