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HealthWiki > New Where There Is No Doctor > Belly Pain, Diarrhea, and Worms > Worms

Worms inside our intestines live off our food and blood. They cause belly aches or diarrhea, and drain us of nutrition and energy. A child with a very bad worm infection may develop anemia (lack of iron) or vitamin A deficiency. Often she will have trouble in school and working around the home, because the infection hurts her ability to concentrate.

Different worms get in our bodies in different ways, live different amounts of time, cause different problems, and may require different medicines. Try to learn how the worms where you live are best prevented and treated. (And if you adapt this book for use in another language or specific place, include details about the particular worms common to your community.) But generally, worm infections can be prevented:

  • Use toilets to improve sanitation.
  • Wash hands. Keep fingernails short so dirt does not get trapped under them.
  • Cook meat well before eating. Do not feed raw meat or feces to livestock.
  • Wear shoes or sandals.
  • De-worm children over 1 year old every 3 to 6 months with albendazole or mebendazole.

Worms that spread from feces to the mouth:
roundworm, whipworm, pinworm

a long, fat worm
Roundworm (Ascaris)
20 to 30 cm long, pink or white color.
a small worm that is very thin at one end
(Trichuris, Trichocephalus)
3 to 5 cm long, pink or grey.
three very small, thin worms
Pinworm, threadworm, seatworm
1 cm long, white, very thin and thread-like.

How these worms spread

Tiny amounts of feces are left on the hands when cleaning the anus after passing stool, or when someone scratches an itchy bottom. Or stool left on the ground is tracked into the house by animals, children, or on people’s feet. Then worms, or their eggs that are in the stool, get under the nails or on the skin. These worms or eggs get into the mouth when:

NWTND bag Page 32-4.png
NWTND bag Page 32-5.png
NWTND bag Page 32-6.png
A child puts his hands in his mouth. Someone cooks for the family. Anyone touches her own or someone else’s mouth.

Worm eggs are too small to see -
that is why they spread so easily


To treat roundworm, whipworm, hookworm, or pinworm, give mebendazole for 3 days. In places where these worms are common, repeat treatment every 3 to 6 months.

Avoid thiabendazole for roundworms. It can make roundworms move up to the nose or mouth and can cause choking and difficulty breathing.

You may be able to treat these worms with home remedies. Eating a little raw garlic or ground papaya seeds each day can help to kill worms.


cartoon drawing of a latrine chasing worms away

For worms, prevention is the best and most important treatment. Without prevention and cleanliness, a person will just get worms again and again.

Toilets: Build a clean, private place to pass stool, away from the house and drinking water. Then children and animals will not track stool into the house. See more information on how to build simple, safe toilets.

Wash your hands, and help children wash their hands too: Wash often and well with soap and water, or with ashes. Wash before preparing food and before eating, and after every time you pass stool.
young boy scratching his anus while giving food to another boy
Help children to wash hands even more often – since they touch everything and frequently put their fingers in their mouths.

If a child is scratching his anus because of worms, he will easily re-infect himself or others. To prevent this:

  • Cut the nails short, so feces and worm eggs do not stick under them.
  • Wash the child’s hands well each morning, before he eats, and after he passes stool.
  • Have the child wear pants during the day. Put him in a snug diaper or pants before bed – so he cannot scratch his anus in his sleep.
  • Prevent itching with a little Vaseline on the anus before bed.

Wash after you handle other people's stool: If you are caring for babies or an ill adult, dispose of their stool into a toilet. Wash their bottoms after they pass stool. And carefully wash your hands after. For more ideas on how to prevent worms and other diseases, see Water and Sanitation.

Other problems caused by these worms

thin young boy with swollen belly
Children with a lot of worms may have hard, swollen bellies.

Roundworm: A severe, untreated roundworm infection can cause problems in the gut or with breathing. Young worms dig into the lungs, causing wheeze, a dry cough, or pneumonia with coughing of blood. This person needs medical help.

When a person has a fever, or when she starts taking worm medicine, the worms may come out in the stools or crawl out through the mouth or nose. Occasionally this causes the person to choke.

Rarely, roundworms cause an obstruction of the gut. Get medical help. Give mebendazole or albendazole on the way.

Whipworm: Whipworm can cause diarrhea, sometimes with blood. In severe infections, this leads to anemia (lack of iron in the blood).

Whipworm can also cause a child to push too hard when passing stool, which may cause a child’s intestine to come part-way out of the anus. This is called rectal prolapse. Pour some cold water on it and it should pull back inside. If not, gently press it back in.

Worms spread by eating undercooked meat:
tapeworm and trichina worm

pieces of different kinds of tapeworm
coiled worm that causes trichinosis
Tapeworm (cestode), and tapeworm pieces (segments). These worms are white or yellow and up to several meters long. Depending on the type of tapeworm, you may see these segments in the stool. The trichina worm cannot be seen in the stool, but this is how it would look if you could see it burrowed into someone’s muscle.

Tapeworms and trichina worms are spread by eating undercooked meat – usually pork. Fish, cows, and carnivores (animals that eat other animals) can also carry different types of these worms.


The tapeworm lifecycle:

Tapeworm eggs in a man's stool lead to tapeworm cysts in a pig's body.
1. Someone eats under-cooked meat. Tapeworm cysts in the meat become tapeworms in his intestines.
2. The tapeworms lay thousands of eggs inside his intestines.
3. A pig eats the man’s stool and the eggs inside that stool.
4. These worm eggs spread throughout the pig’s body, forming cysts inside its muscles.
Eggs that enter
a person’s mouth (for
example, if he does not
wash his hands
after passing stool),
can cause cysts in
his brain. This may
cause headaches
seizures, or death.

If you find a small, flat, white piece (segment) of tapeworm in the stool or underclothing, treat for tapeworm.

Treatment (Trichina worm infection)
unconscious man lying on the ground

Give niclosamide or praziquantel. If there are seizures, get medical help. The person will need anti-seizure and steroid medicines.

Trichinosis (trichina worm infection)

Within a week of eating infected meat, someone with trichinosis may get a stomach ache, nausea, and diarrhea. If everyone who ate the same pork has a stomach ache within a week of eating it, get treatment for trichinosis.

After a week the infection can spread to the muscles or brain causing:

  • fever and chills.
  • muscle pain or pain in the joints.
  • swelling around the eyes or of the feet.
  • bleeding in the whites of the eyes, pain in the eyes, or vision problems.
  • small bruises.

Give albendazole or mebendazole. Steroid medicines might be needed too.

Prevention for tapeworm and trichinosis
pig eating feces
  • Pen pigs away from the house – so their stool is not tracked into the home or touched by children.
  • Do not feed raw meat or feces to pigs – infection will follow.
  • Cook meat well, especially pork. Cooking will kill tapeworm cysts.
  • Wash hands after passing stool and before cooking or eating.


two small worms
1 cm long, red

Hookworms can be one of the most dangerous diseases of childhood, because they feed off the child’s blood and can cause anemia. A child who is anemic, pale, or eats dirt may have hookworms. If possible, his stools should be tested for hookworm.

How hookworms spread (start with number 1 below)

boy's naked body showing feet, lungs, throat, stomach, and gut
The baby
hookworms enter a person’s bare feet. This can cause red marks on the feet and itching.
2. In a few days they reach
the lungs through the blood
stream. This may cause a
dry cough (rarely with blood).
3. The person coughs up the young worms and swallows them.
4. A few days later the person may have diarrhea or a stomach ache.
5. The hookworms attach themselves to the walls of the gut. Many worms can cause weakness and severe anemia.
6. The hookworms eggs leave the body in the person’s stools. The eggs hatch on moist soil.

Give mebendazole to treat hookworm.

Treat anemia by eating foods rich in iron and taking iron tablets.

child using a latrine Protect children from hookworm: Build latrines and wear sandals or shoes.
feet wearing shoes and sandals

This page was updated:16 Aug 2018