Science Inventory

Determining UV Inactivation of Toxoplasma gondii Oocysts by Using Cell Culture and a Mouse Bioassay

Citation:

WARE, M. W., S. J. AUGUSTINE, D. ERISMAN, M. J. See, L. J. WYMER, S. L. HAYES, J. P. Dubey, AND E. VILLEGAS. Determining UV Inactivation of Toxoplasma gondii Oocysts by Using Cell Culture and a Mouse Bioassay. APPLIED AND ENVIRONMENTAL MICROBIOLOGY. American Society for Microbiology, Washington, DC, 76(15):5140-5147, (2010).

Impact/Purpose:

The overall objective of this task is the development of improved occurrence detection methods for protozoan parasites and Microsporidia. Since this work is a primary focus of the Branch, this task supports several individual projects related to sample preparation and protozoan detection. Together these projects will lead to complete methods able to support the UCMR and the CCL2 and CCL3.

Description:

The effect of UV exposure on Toxoplasma gondii oocysts has not been completely defined for use in water disinfection. This study evaluated UV irradiated oocysts by three assays: a SCID mouse bioassay, an in vitro T. gondii oocyst plaque assay (TOP-assay), and a quantitative reverse-transcriptase real-time PCR (RT-qPCR) assay. The results from the animal bioassay show that 1 and 3 log10 inactivation is achieved with 4 mJ/cm2 UV and 10 mJ/cm2 UV, respectively; but 4 log10 inactivation is not achieved with even higher UV exposures. TOP-assay results, but not RT-qPCR results, correlate well with bioassay results. In conclusion, a 3 log10 inactivation of T. gondii oocysts is achieved by a 10 mJ/cm2 low pressure UV, and the in vitro TOP-assay is a promising alternative to the mouse bioassay.

Record Details:

Record Type:DOCUMENT( JOURNAL/ PEER REVIEWED JOURNAL)
Product Published Date:08/01/2010
Record Last Revised:05/24/2012
OMB Category:Other
Record ID: 218892