Faecal Strep vs. Enterococci

John Gentile yjgent at cox.net
Sat Nov 29 23:11:34 EST 2003


in article LAW12-F153TGJ2TUSzb000216bf at hotmail.com, "agy lee" at
agyleesy at hotmail.com wrote on 11/29/03 7:23 PM:

> I have two questions that require some advice:
> 
> 1. Are these these bacteria the same or are they completely different?
> Under the new WHO guidelines for recreational water quality it says that
> these two are interchangeable, so I'm a bit confused as I thought they were
> different. So, if a guideline refers to enterococci does it imply FStrep as
> well?
> 
> 2. I'm looking at the APHA Standard methods and there are two different
> methods for testing for FStrep and Enterococci.  However, in the
> verification stage it says that colonies can be tested for growth on NaCl to
> test for Enterococci.  Does this mean that i can test for Enterococci
> following the FStrep procedure and base my Enterococci counts on this?
> 
> Thank you for your assistance.
> 
> _________________________________________________________________
> Find it on the web with MSN Search. http://search.msn.com.sg/
> 
> ---

The organisms in the genus Enterococcus used to be included in the
Streptococcus genus. Streptococcus faecalis is now Enterococcus faecalis.
The Enterococci will grow in 6.5% NaCl where Strep will not. Many years ago
I used a purple broth called SF Broth. Enterococcus would turn the broth
yellow. A newer test is the PYRase test that is positive for Enterococcus
and negative for most Streps - Group A Streptococcus pyogenes is PYR pos.
Another test is usually added to separate those 2 - the GLCase. Enterococcus
is positive and Strep. Pyogenes is neg.

As far as groupings go, Enterococcus sp. Used to be classified as a Group D
Strep. They do agglutinate the Group D antisera, and there are still
Streptococcus organisms listed under Group D that are not Enterococcus.

-- 
John Gentile                            Secretary,  Rhode Island Apple Group
yjgent at cox.net                      RIAG Web page:  www.wbwip.com/riag/
"I never make mistakes, I only have unexpected learning opportunities!"






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