Thread worms are the most common infecting worms.
The female crawls through the anus and lays her eggs in the surrounding skin. When your child scratches her bottom, the eggs may get under her nails and are ingested again when she puts her hands into her mouth. Your doctor will prescribe a single-dose treatment that will destroy both the worms and the eggs. Since worms are highly infectious, all members of the family should take the anti-worm treatment. Repeat the dose after a fortnight.