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Giardia is a tiny parasite that causes diarrhea and can be spread by contaminated water, food, or surfaces. Learn how to prevent getting sick, how to diagnose and treat Giardia infection, and how to protect your pet from this parasite.
- Illness & Symptoms
Giardia can be found in every region of the United States...
- Giardia & Pets
Dog and cat stool (poop) can contain Giardia germs and may...
- Diagnosis & Detection
Because Giardia infections can be hard to diagnose, doctors...
- Transmission
Giardia can be found in every region of the United States...
- General Information
What is giardiasis? Giardiasis is a diarrheal disease caused...
- For Medical Professionals
Giardia duodenalis (also referred to as Giardia intestinalis...
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Some people with giardia infection never develop signs or symptoms, but they still carry the parasite and can spread it to others through their stool. For those who do get sick, signs and symptoms usually appear one to three weeks after exposure and may include:
•Watery, sometimes foul-smelling diarrhea that may alternate with soft, greasy stools
•Fatigue
•Stomach cramps and bloating
•Gas
•Nausea
Call your doctor if you have loose stools, stomach cramping and bloating, and nausea lasting more than a week, or if you become dehydrated. Be sure to tell your doctor if you're at risk of giardia infection — that is, you have a child in child care, you've recently traveled to an area where the infection is common, or you've swallowed water from a lake or stream.
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Giardia parasites live in the intestines of people and animals. Before the microscopic parasites are passed in stool, they become encased within hard shells called cysts, which allows them to survive outside the intestines for months. Once inside a host, the cysts dissolve and the parasites are released.
Infection occurs when you accidentally swallow the parasite cysts. This can occur by swallowing unsafe water, by eating infected food or through person-to-person contact.
The giardia parasite is a very common intestinal parasite. Although anyone can pick up giardia parasites, some people are especially at risk:
•Children. Giardia infection is far more common in children than it is in adults. Children are more likely to come in contact with feces, especially if they wear diapers, are toilet training or spend time in a child care center. People who live or work with small children also are at higher risk of developing giardia infection.
•People without access to safe drinking water. Giardia infection is rampant wherever sanitation is inadequate or water isn't safe to drink. You're at risk if you travel to places where giardia infection is common, especially if you aren't careful about what you eat and drink. The risk is greatest in rural or wilderness areas.
•People who have anal sex. People who have anal sex or oral-anal sex without using a condom or other protection are at increased risk of giardia infection, as well as sexually transmitted infections.
Giardia infection is almost never fatal in industrialized countries. But it can cause lingering symptoms and serious complications, especially in infants and children. The most common complications include:
•Dehydration. Often a result of severe diarrhea, dehydration occurs when the body doesn't have enough water to carry out its normal functions.
•Failure to thrive. Chronic diarrhea from giardia infection can lead to malnutrition and harm children's physical and mental development.
•Lactose intolerance. Many people with giardia infection develop lactose intolerance — the inability to properly digest milk sugar. The problem may persist long after the infection has cleared.
No drug or vaccine can prevent giardia infection. But commonsense precautions can go a long way toward reducing the chances that you'll become infected or spread the infection to others.
•Wash your hands. This is the simplest and best way to prevent most kinds of infection. Wash your hands with soap and water for at least 20 seconds after using the toilet or changing diapers, and before eating or preparing food. When soap and water aren't available, you can use alcohol-based sanitizers. However, alcohol-based sanitizers aren't effective in destroying the cyst form of giardia that survives in the environment.
•Purify wilderness water. Avoid drinking untreated water from shallow wells, lakes, rivers, springs, ponds and streams unless you filter it or boil it for at least 10 minutes at 158 F (70 C) first.
•Wash produce. Wash any raw fruits and vegetables with safe, uncontaminated water. Peel the fruit before eating it. Avoid eating raw fruits or vegetables if traveling in countries where they may have contact with unsafe water.
•Keep your mouth closed. Try not to swallow water when swimming in pools, lakes or streams.
•Use bottled water. When traveling to parts of the world where the water supply is likely to be unsafe, drink and brush your teeth with bottled water that you open yourself. Don't use ice.
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Oct 28, 2020 · Giardiasis is a common illness caused by a parasite that can spread through contaminated water, food and surfaces. It may cause diarrhea, stomach cramps and other symptoms. Antibiotics can treat it, but prevention is important. Learn more about giardiasis from Cleveland Clinic.
Aug 15, 2017 · Giardiasis is a parasitic infection that’s diagnosed by examining a stool sample and sometimes taking a tissue sample from the small intestine. It’s caused by a microscopic parasite called Giardia lamblia, which can be found in contaminated food, water, and soil. You can get giardiasis by eating contaminated food or drinking contaminated water, or by contact with infected people. Symptoms include diarrhea, nausea, abdominal pain, and weight loss. Treatment includes antibiotics or antiparasitic drugs.
- Amanda Delgado
Nov 8, 2022 · Learn how to diagnose and treat giardia infection, a parasitic infection that causes diarrhea and other symptoms. Find out the symptoms, causes, diagnosis methods, treatment options and prevention tips from Mayo Clinic experts.
Giardia lamblia is a protozoan parasite that causes giardiasis, a disease of the intestine. Learn about its life cycle, transmission, symptoms, diagnosis, and treatment from the CDC - DPDx website.
