1. Giardia lamblia is a causal agent of giardiasis. This is a
parasitic disease caused by
Giardia duodenalis (also known as
G. lamblia and
G. intestinalis). Infected individuals who experience symptoms (about 10% have no symptoms) may have
diarrhea,
abdominal pain, and
weight loss. Less common symptoms include vomiting and
blood in the stool. Symptoms usually begin 1 to 3 weeks after exposure and, without treatment, may last two to six weeks or longer.
Giardiasis usually spreads when Giardia duodenalis cysts within
feces contaminate food or water that is later consumed orally. The disease can also spread between people and through other animals. Cysts may survive for nearly three months in cold water. Giardiasis is diagnosed via stool tests.
Prevention may be improved through proper
hygiene practices. Asymptomatic cases often do not need treatment. When symptoms are present, treatment is typically provided with either
tinidazole or
metronidazole. Infection may cause a person to become
lactose intolerant, so it is recommended to temporarily avoid lactose following an infection.
Resistance to treatment may occur in some patients.