Decoding Cryptosporidium

Analysis of he complete genome sequence of Cryptosporidium parvum, published in the March 26 Science, reveals why this parasite has proven so notoriously difficult to treat effectively—it lacks many of the proteins targeted by current antiparasitic drugs.

C. parvum is a water- and food-borne pathogen causing acute gastrointestinal disease in healthy people, but it can cause a life-threatening chronic severe diarrhea in those who are malnourished or immunocompromised. “Despite intensive efforts over the past 20 years, there is currently no effective therapy for treating or preventing C. parvum infection in humans,” said lead author Mitch Abrahamsen, of the University of Minnesota College of Medicine.

Unlike many parasitic diseases, cryptosporidiosis is not just limited to the developing world—it is a global problem. In 1993, a major outbreak in Milwaukee infected more than 400,000 people, including about half of Milwaukee's residents with AIDS, nearly 70% of whom died within 6 months.

The ...