Giardiasis

Excerpt

Giardiasis, an enteric infection caused by the protozoan parasite Giardia duodenalis, is a common condition, especially in low-resource settings. Individuals with giardiasis often present with complaints of flatulence and watery diarrhea. G duodenalis, the flagellated protozoan responsible for the infection, ranks as the most commonly found intestinal parasite in the United States and is also recognized as the most prevalent protozoal intestinal parasite globally. Giardia infections are more widespread among children than adults.

International travelers, outdoor enthusiasts, and daycare workers in the United States are the primary groups susceptible to this disease. While some individuals may remain asymptomatic, others can experience severe manifestations leading to dehydration and weight loss. Treatment with nitroimidazole or antihelminthic medication can be highly effective and often leads to a rapid recovery.

G duodenalis can cause asymptomatic colonization or a diarrheal illness, which can either be acute or chronic. Studies have revealed its presence in up to 80% of water supplies sourced from lakes, ponds, and streams and around 15% of filtered water samples. In developing countries, this parasite often causes chronic diarrhea and growth impairment in children. High-risk groups susceptible to giardiasis include immunocompromised individuals, travelers visiting highly endemic regions, and certain sexually active homosexual men. Members of these groups are frequently symptomatic.