Giardiasis, or Giardia infection, is one of the most common waterborne diseases in the United States. Also known as “beaver fever,” Giardia parasites that cause the intestinal infection are typically found in backwater streams and lakes, but have also been found in municipal water supplies, swimming pools, and wells.
Giardia is a major cause of human illness, both in the United States and worldwide. Data suggest that the infection can be linked to later development of arthritis or joint pain.
In a new study, Julia Painter, assistant professor of global and community health, along with colleagues at the Centers for Disease Control and Prevention’s National Center for Emerging Zoonotic and Infectious Diseases, use data from a large insurance cohort to determine if there is an association between Giardia and arthritis or joint pain. The study is published in Epidemiology and Infection.
“While case studies and smaller research studies have demonstrated that arthritis or joint pain can occur after a person has giardiasis, there is very limited, large scale epidemiological research that examines this association,” Painter said. “By starting to use larger data sets, we can determine whether there is epidemiological support for the development of joint pain following giardiasis identified in smaller, uncontrolled studies.”
The authors analyzed data from 17,913 patients in the Truven Health Analytics MarketScan Commercial Claims and Encounters database, which contains medical billing data from large employers, health plans, and government and public organizations. The results showed that people with Giardia infection had 51 percent increased odds of being diagnosed with joint pain in the six months after their giardiasis diagnosis.
“Despite several limitations of the study, including using medical billing data as opposed to medical records and restrictions of the MarketScan database, our findings indicate that giardiasis is epidemiologically associated with joint pain, in a timeframe that could plausibly be considered as reactive arthritis,” Painter said. “These results demonstrate the need to conduct further studies that examine the clinical, epidemiologic, and biological associations between Giardia and joint pain.”