WATER QUALITY: Analytical Methods--"Salmonella and Shigella (Diatomaccous earth and membrane filter method)" by Theodore A. Ehlke



                                                May 6, 1975


QUALITY OF WATER BRANCH TECHNICAL MEMORANDUM NO. 75.21

Subject: WATER QUALITY: Analytical Methods--"Salmonella and 
         Shigella (Diatomaccous earth and membrane filter 
         method)" by Theodore A. Ehlke

The attached provisional method for Salmonella and Shigella 
is a complex, qualitative procedure for the presumptive and 
confirmed presence of pathogenic enterobacteriaceae in water. 
The more common diseases caused by Salmonella include typhoid 
and paratyphoid fevers and salmonellosis. Shigella causes 
bacillary dysentery, also known as shigellosis.

The method is based primarily on procedures described by 
Difco Laboratories (1953, 1968, 1969A, 1969B, 1971A, and 
1971B). It is comparable with the Salmonella-Shigella method 
that is being prepared by the Environmental Protection 
Agency.

The method is approved for use in the Water Resources 
Division by those individuals who have special training and 
knowledge in the handling of pathogenic organisms. Extreme 
care must be taken since the method provides for the 
reproduction and enhancement of growth of pathogenic 
bacteria. Following completion of tests, all cultures must be 
destroyed and all equipment sterilized by autoclaving at 
120!C for 30 minutes at 15 psi.

Questions or comments pertaining to the method should be 
directed to the Chief, Quality of Water Branch (mail stop 
412, Reston, Virginia).



                                R. J. Pickering

Attachment

WRD Distribution: A,B,FO-LS,PO


(Attachment contains charts and diagrams that cannot be 
transferred to the Electronic Memorandum system.  A hard copy 
of the attachment may be obtained from the Office of Water 
Quality.)