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Keeping kids free from parasites
Protect your family
When to see the doctor


Invasion of the organisms
Invasion of the organisms

Parasites are common causes of food-borne and water-borne illness. Organisms such as Giardia, Cryptosporidium and Entamoeba histolytica typically cause mild to severe diarrhea and gastrointestinal symptoms.

These organisms often live in their hosts’ digestive tracts and are excreted in feces. Some parasites journey from host to host via insects like mosquitoes that spread malaria or deer ticks that pass on a flulike illness called babesiosis. Others may transfer to humans from their pets such as toxoplasmosis from cats. Parasites like head lice and pinworms cause symptoms that are more annoying than illness-provoking. Lice may cause a child to scratch at his or her head and neck, leaving a tender, red rash or even a subsequent bacterial infection. Pinworms, which live in the intestine, crawl out of the anus at night to lay eggs, causing your child to have a restless sleep from an itchy bottom.

Of all the germs or organisms—or cooties in kid-speak—that cause illness, some of the most insidious and likely to give you the heebie-jeebies are parasites. Unlike bacteria or viruses, parasites behave like tiny animals that stealthily invade and take up residence in the body, living, feeding and multiplying in the intestinal tract, lungs, liver, skin or brain.

Children are at particular risk for parasitic illness because they typically have less-than-ideal hygiene habits and often place their hands and other objects in their mouth. Parasites can be present in food, water, soil and insects and range in size from tiny, one-celled organisms to worms that can grow many feet in length. Parasites can enter the body through contaminated food or water or anything put in the mouth that’s come in contact with an infected person’s or animal’s stool. Kids can come in contact with parasites when playing in sandboxes and parks, while swimming and when touching snakes, turtles, lizards and other reptiles.

Some parasites are spread person to person or by shared personal belongings. Head lice, for example, are transmitted by sharing hats, clothing, bedding, combs and brushes with a person who has lice.

Protect your family

Unfortunately, no vaccinations are yet available that can protect against illnesses caused by parasites. But you can help keep your family healthy by following these measures:

  • Cook food properly. Make sure meats—especially pork, lamb and wild game—are cooked to the correct temperature. Drink only pasteurized milk, cider and juice.
  • Wash all produce. Use safe water to thoroughly clean any fruits and vegetables you plan to eat raw. If you can’t be sure about the water’s safety, peel or cook the produce. Avoid using untreated manure to fertilize fruits and vegetables.
  • Drink municipal or bottled water. When hiking or camping, boil any untreated water for at least one minute before drinking. When traveling to countries where the water supply may be unsafe, drink only bottled beverages.
  • Swim safely. Parasites may be in many types of recreation water like lakes, rivers, ponds and streams and even in swimming pools, hot tubs, water parks and fountains. Chlorine doesn’t kill all organisms, so teach your children not to swallow water when swimming. Check children’s swim diapers often and wash their bottoms well before letting them back into the water. Keep kids out of recreation water when they have diarrhea.
  • Wash hands well. Make frequent hand washing a routine in your home. Insist everyone wash their hands with soap and water before preparing food and eating and after using the bathroom, gardening, changing a diaper or touching pets. Discourage thumb sucking and nail biting.
  • Don’t share personal items. Teach children not to share or trade hats, scarves, brushes or combs. Buy your children their own protective sports gear like batting helmets.
  • Keep pets healthy. Visit the veterinarian regularly to keep your pets healthy, dewormed and free from ticks and fleas. Wear gloves and clean up thoroughly when changing the cat’s litter box. If you’re pregnant, delegate this chore to another—becoming ill with taxoplasmosis (spread through contact with cat feces) can cause birth defects. Cover sandboxes to keep cats out.

When to see the doctor

Take your child to the doctor anytime he or she is ill or has diarrhea lasting more than three days. Go earlier if you have reason to suspect a parasite or if diarrhea involves a large loss of fluids or contains blood. Take note of any fever, vomiting, rash, unexplained itching, weight loss, joint pain or abdominal discomfort.

Let the doctor know if anyone in the family works in a child care center, has recently traveled or has gone camping, hiking or swimming.