The parasite attaches to cells on the wall of the small intestine, for nourishment. Children are more likely to get this illness than adults, because of their frequent hand to mouth activity. Symptoms may appear from five to 25 days after exposure, but usually within seven to ten days. The stools may be foul-smelling and contain mucus, but will not usually be bloody.
Untreated diarrhea can lead to dehydration and weight loss.
Many people with giardiasis have no symptoms at all, but could still pass the infection to others. Diagnosis is made by examining the stool under a microscope to look for the organism. Treatment is by antibiotics prescribed by your doctor. Severe diarrhea may require the need for intravenous fluid replacement to prevent dehydration. Those with active diarrhea and are unable to control their bowel movements, such as infants and young children, should be excluded from day-care and similar settings until they have been treated and have recovered.