Water Intelligence Online © IWA Publishing 2005

Comparing Cell Culture and Mouse Assays for Measuring Infectivity of Cryptospordium

Paul Rochelle*, M Marshall, J Mead, J Rosen

*Metro Water District of Southern California, 700 Moreno Avenue, La Verne, CA 91750-3399, USA

The objective of this research was to compare in-vitro cell culture methods with a mouse assay for measuring infectivity of Cryptosporidium parvum oocysts. The specific objectives were to (1) compare the dose response and sensitivity of cell culture and mouse assays with multiple isolates; (2) compare infectivity methods with oocysts exposed to environmental water samples; (3) determine the reproducibility and variability of the methods; and (4) compare cell culture and animal assays for assessing ozone and UV disinfection.

The water industry should adopt in-vitro cell culture as a routine method for measuring the infectivity of waterborne C. parvum and C. hominis oocysts. This project has demonstrated that cell culture has equivalency with the standard CD-1 mouse assay and cell culture assays can be applied to oocysts recovered from water using approved methods. However, there needs to be a thorough, robust, and well-controlled study to compare the various cell culture-based assays for measuring C. parvum and C. hominis infectivity. This evaluation should include inter-laboratory comparisons and round-robin testing. Cell culture-based assays should also be used to assess disinfection of C. hominis isolates.

Full article (PDF Format)

UNIQUE ID: 200506AF91027F