Cryptosporidiosis, an infectious gastrointestinal disease caused by the parasite Cryptosporidium, is the leading cause of waterborne diseases among humans in the United States, according to the Centers for Disease Control and Prevention (CDC).
In a new study, Julia Painter, assistant professor of global and community health, along with colleagues at the CDC’s Division of Foodborne, Waterborne, and Environmental Diseases, conducted the first analysis of the epidemiology of cryptosporidiosis cases in the United States from 1995, when national reporting began, to 2012. The analysis is published in Epidemiology and Infection.
“Cryptosporidium can be transmitted through drinking water and recreational water, and has contributed to a significant increase in the incidence of recreational water-associated outbreaks in the United States,” Painter said. “While about 8,500 U.S. cases are reported annually, estimates indicate as many as 748,000 cases occur and the majority go unreported.”
The study, which analyzed data from 102,835 cases of cryptosporidiosis reported to the CDC from 1995-2012, demonstrated that there has been an increase in reporting of cryptosporidiosis cases, as well as an evolving composition of these cases. The ratio of male to female cases has changed from male to female predominance, and although overall rates remain highest in children, rates have increased significantly among elderly adults.
“Our results demonstrate the need to address the evolving epidemiology of cryptosporidiosis and fill the gap in our knowledge base,” Painter said. “This data highlights where further research is needed to explain increases in reporting of cryptosporidiosis cases and to identify risk factors within specific population subgroups.”