Ask an Expert with Anne Chi - Microbiological Presumptive Positives
Overview
Eurofins Microbiology Laboratories, Inc. is made up of a network of microbiology labs located all throughout the US to support microbiological testing needs. Each lab has dedicated customer support so you get answers fast. Our Ask an Expert Series showcases our scientists from around the country and answers questions customers frequently ask. Videos are published weekly on all of social media platforms.
Ask an Expert Series - Topic #6
What do I do when I get a presumptive positive? Can I re-test the same lot?
"Treat the result as if it is a confirmed positive. Delaying reaction could mean you have product in commerce that is contaminated or that you are continuing to produce product that is of questionable safety. If the presumptive is confirmed, retesting the lot with a subsequent negative result cannot be used to salvage the lot. Pathogens are frequently not uniformly distributed in a lot so a negative on another sample may be due to nonuniformity rather than assuming the lot is free of contamination." - Anne Chi, Business Unit Manager of Eurofins Microbiology Laboratories, Inc. in Garden Grove, CA.
