My laboratory focuses on enteric infections and the host response. This includes viral, bacterial and protozoan pathogens of veterinary and medical importance causing acute or chronic diarrhea in the immunocompetent or the immunodeficient host. In recent years investigations have focused specifically on a number of areas. These include: The biology, pathogenesis, immunology, epidemiology, diagnosis, treatment, prevention and control of cryptosporidiosis and microsporidiosis in children from developing countries, and in individuals with HIV/AIDS; Mechanisms of disease caused by Shiga-toxin producing E. coli (STEC), and development of therapy against the associated hemolytic uremic syndrome (HUS) - a complicating acute kidney failure in children; Development of botulinum antitoxin therapy and control of intoxication in humans; Development of strategies for identification, characterization and risk assessment of food and waterborne pathogens. Development and preclinical evaluation of enteric human vaccines for developing countries; Clostridium difficile studies focused the biology, pathogenesis, and development of therapy and vaccines; and Characterization of the human microbiome in the germfree pig model to investigate human gastrointestinal disorders.