Part of the overall approach to controlling the risk of waterborne
cryptosporidiosis is to improve analytical methods for detection. The microscopic
technique which has been utilized and gradually improved over the past 15 years
is still labor intensive, slow, expensive, and criticized for poor recovery and
reproducibility (Simons et al, 2001). Furthermore, the currently used routine
microscopic assay is still only capable of detecting the numbers of oocysts
present. It provides no information on species, viability, or virulence of the
detected oocysts. Research methods have been developed utilizing infection of
cell lines to determine viability and virulence of oocysts in samples (Slifko et al,
1999; Rochelle et al, 2002). However the difficulties encountered with
maintenance of sterile cell lines generally restricts use of the technique to the
research setting. Two years ago the
DuPont Qualicon Corporation, in association with the American Waterworks
Service Company, developed and marketed an automated polymerase chain
reaction (PCR) detection technique suitable for routine laboratory use. The
Pittsburgh Water & Sewer Authority (PWSA) Laboratory purchased one of these units and
incorporated it into routine use, alongside the microscopic method (USEPA
method 1623), for routine analysis of raw and treated water samples for the
presence of Cryptosporidium oocysts. This paper describes the results of a
comparison of the two methods conducted over a period of more than
one year. These methods include a version of the USEPA method 1623 published in April 2001 (USEPA, 2001), and a BAX PCR method. In this project the two techniques were used to analyze monthly river
and drinking water samples collected at the PWSA Drinking Water Treatment
Plant. The methods were also used to analyze samples of river water collected
from various sites along the length of the Allegheny River as well as several
samples of groundwater. The study design is discussed along with the results.
Includes 12 references, tables.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 270 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 14 |
| Published : | 11/01/2002 |
