The best way to prevent ascariasis is to always:

• Avoid ingesting soil that may be contaminated with human feces, including where human fecal matter ("night soil") or wastewater is used to fertilize crops.
• Wash your hands with soap and warm water before handling food.
• Teach children the importance of washing hands to prevent infection.
• Wash, peel, or cook all raw vegetables and fruits before eating, particularly those that have been grown in soil that has been fertilized with manure.

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Transmission of infection to others can be prevented by

• Not defecating outdoors.
• Effective sewage disposal systems.

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