The 10 Most Common Parasitic Infections

10. Giardiasis

Giardiasis is one of the most common parasites worldwide, and the most common intestinal parasitic infection in the United States. An estimated 33% of people in developing countries have contracted the infection, as well as 2% of adults and around 7% of children in developed countries. Individuals acquire giardiasis by consuming food or water contaminated with the Giardia intestinalis parasite. One of the most common methods of transmission is coming into contacting with a surface or person carrying the parasite and unknowingly swallowing it. Symptoms of giardiasis include a variety of gastrointestinal disturbances including diarrhea, bloating, stomach pain, and nausea.