How Does Cryptosporidium Cause Diarrheal Disease?

Species found in the genus Cryptosporidium are protozoan parasites that cause diarrheal disease with a global distribution. They mainly affect children, causing a self-limited diarrhea in healthy individuals; nevertheless, in people with acquired immunodeficiency disorder or AIDS, the disease can be quite severe and result in weight loss or malnutrition.

Intestinal cryptosporidiosis continues to be an important public health concern worldwide, most notably through outbreaks caused by contaminated food or water, and sometimes also from the infected host. Therefore adhering to proper sanitation and hygiene measures is important for preventing this illness.

Water treatment and water avoidance

Water purification is a paramount public health measure, but it must be noted that chlorination has little effect on the Cryptosporidium oocysts;
For that purpose, antimicrobial agents such as rifabutin and clarithromycin are most often used, based on the results of retrospective studies and controlled trials that noted lower incidence of the disease in treated groups when compared to placebo groups.

Research on vaccines

To date, no effective vaccine is at our disposal to prevent intestinal cryptosporidiosis. A proof of concept that a vaccine might represent an effective preventive approach stems from observing age-related declines of infection rates among children from developing countries, as well as human challenge research studies demonstrating protection linked to previous exposure.

Nevertheless, efforts to develop an efficacious vaccine are hampered by incomplete understanding of the immune responses correlating with protection. Immunodominant antigens found on the surface of the invasive stage of the parasite, as well as antigens associated with sexual and intracellular stages are potential targets of interest. In addition, passive and other new immunotherapies are also being