Definition:
Ascariasis is an intestinal infection caused by the roundworm Ascaris lumbricoides.
Symptoms:
- Abdominal pain, nausea, and diarrhea.
- Weakness, malnutrition, and in severe cases, intestinal blockage.
Prevention:
1. Proper sanitation and disposal of human feces.
2. Washing vegetables and fruits before eating.
3. Maintaining personal hygiene, like handwashing with soap.
Treatment:
- Anti-helminthic drugs such as albendazole or mebendazole are used to kill the worms.
Final Answer:
\[
\boxed{\text{Ascariasis is caused by Ascaris lumbricoides, prevented by hygiene and treated with albendazole/mebendazole.}}
\]