Giardia Infections

Summary

Giardiasis is an illness caused by a parasite called Giardia intestinalis. It lives in soil, food, and water. It may also be on surfaces that have been contaminated with waste. You can become infected if you swallow the parasite. You can also get it if you’re exposed to human feces (poop) through sexual contact.

The risk of getting giardia is higher for travelers to countries where it is common, people in child care settings, and those who drink untreated water.

Diarrhea is the main symptom of giardia infection. Others include:

• Passing gas
• Greasy stools
• Stomach cramps
• Upset stomach or nausea

These symptoms may lead to weight loss and loss of body fluids. Some people have no symptoms at all. Symptoms of infection often last two to six weeks. Stool sample tests can diagnose it. You often need to collect several samples to test. Doctors use several drugs to treat it.

The best way to prevent giardia infection is to practice good hygiene, including frequent hand washing. You should not drink water that may be contaminated. You should also peel or wash fresh fruit and vegetables before eating.

Centers for Disease Control and Prevention

National Institute of Allergy and Infectious Diseases

Find an Expert

• Centers for Disease Control and Prevention Centers for Disease Control and Prevention
• National Institute of Allergy and Infectious Diseases National Institute of Allergy and Infectious Diseases

Clinical Trials

• ClinicalTrials.gov: Giardiasis National Institutes of Health

Diagnosis and Tests

• Diagnosis of Parasitic Diseases Centers for Disease Control and Prevention
• Giardia: Illness & Symptoms Centers for Disease Control and Prevention
• Ova and Parasite Test National Library of Medicine

Related Issues

• Germs that Can Contaminate Tap Water Centers for Disease Control and Prevention
• Giardia & Pets Centers for Disease Control and Prevention
• Travelers’ Health: Water Disinfection Centers for Disease Control and Prevention

Start Here

• Giardia Infection (Giardiasis) Mayo Foundation for Medical Education and Research
• Giardia: General Information Centers for Disease Control and Prevention
• Giardiasis American Academy of Family Physicians

Treatments and Therapies

• Giardia Infection Treatment Centers for Disease Control and Prevention

Prevention and Risk Factors

• Giardia Prevention and Control Centers for Disease Control and Prevention

Patient Handouts

• Giardiasis Medical Encyclopedia
• Stool ova and parasites exam Medical Encyclopedia

Children

• Giardiasis (For Parents) Nemours Foundation

Journal Articles

• Giardia Infections