Cryptosporidium is a protozoan parasite that causes gastroenteritis in man and animals. One mode of transmission of cryptosporidiosis is by the fecal-oral route. A method was developed for the concentration and detection of Cryptosporidium oocysts in water to study this organism's occurrence in the environment and its potential for waterborne disease transmission. Oocysts from an infected calf were used in experiments and monoclonal antibody labeled with fluorescein isothiocyanate was used for oocyst detection. A concentration method was developed using spun polypropylene cartridge filters. Optimal conditions for concentration, filter elution, filter porosity, and detection were determined by passage of 20-L volumes of tapwater seeded with 10⁵-10⁶ oocysts through the filters. The best method incorporated a 1-μm filter; 2 L eluent containing 0.1% Tween 80; backflush of eluent through filter; cutting the filter; mechanically shaking filter and eluate; and for 378-L volumes, three successive washings of filter material. Modifications were made when attempting to recover 10²-10³ oocysts in 378-L volurnes. These included addition of 1% Tween 80 and 1% sodium dodecyl sulfate (both made in distilled water) to the pellet, followed by homogenization, sonication, Sheather's flotation, and examination of the entire final preparation using a slide antibody test. To distinguish oocysts from other organisms such as yeast which may cross-react with the antibody, crystal violet and acid-fast stains were used. Cryptosporidium oocysts were isolated from secondarily treated sewage and identified on the basis of size, shape, reaction with antibody, acid-fastness, and inability to take up crystal violet. Limited studies with hepatitis A virus (HAV), a cause of waterborne disease, were performed using the HAS-15 strain of HAV and the FRhk-4 cell line. Four procedures used for concentration and detection of HAV in water were developed. They were radioimmunoassay for detection of viral antigen, production of HAV stocks, radioimmunofocus assay for quantitation of infective virus, and inhibition of certain strains of enteroviruses other than HAV, by guanidine.

Thesis (M.S. - Nutrition and Food Science)--University of Arizona, 1986. / Includes bibliographical references (leaves 34-36).

Thesis (Ph. D. - Microbiology and Immunology)--University of Arizona, 1985. / Includes bibliographical references (leaves 134-143).

Thesis (Ph. D. - Microbiology and Immunology)--University of Arizona, 1985. / Bibliography: leaves 142-161.

Thesis (Ph. D. - Microbiology and Immunology)--University of Arizona, 1985. / Includes bibliographical references (leaves 118-127).

Thesis (M.S. - Microbiology and Immunology)--University of Arizona, 1985. / Includes bibliographical references (leaves 54-59).

Thesis (M.S. - Nutrition and Food Science)--University of Arizona, 1986. / Includes bibliographical references (leaves 58-62).

Since their discovery in 1973, rotaviruses have been reported to be responsible for waterborne outbreaks of gastroenteritis. The simian rotavirus (SA11) was used as a model for the human strains during the development of the method for concentration of rotaviruses from drinking and naturally occurring waters. The microporous filter method developed was capable of recovering an average of 49% of the input virus from 20 liters of tap water and an average of 31% from 378 liters. Of the various eluents evaluated, a mixture of 10% tryptose phosphate broth and 3% beef extract (pH 10.0) was found to give the greatest efficiency of elution. The 1MDS filters were found to be superior to the 50S for the concentration of SA11. The method developed was successfully used to concentrate viruses from environmental waters. Indigenous viruses were isolated from waters in Bolivia and Colombia. Several treatment plants as well as raw surface and groundwaters were sampled for the presence of entero— and rotaviruses. Rotaviruses were isolated from one sample which had undergone complete treatment and met all current standards for potability. This study indicated that enteric viruses can be found in drinking waters considered safe due to the absence of indicator bacteria. Prior to this study there were no reports of the occurrence of enteric viruses in water in Colombia or Bolivia. The results of this study also indicate the need for some type of virus monitoring of waters which are contaminated with sewage in order to evaluate the impact of these viruses on the population.

No description available.

Thesis (Ph.D. - Microbiology and Immunology)--University of Arizona. / Includes bibliographical references (leaves 132-134).