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DrOAB, Doctor (MD)
Category: Health
Satisfied Customers: 1032
Experience:  In practice since 2000.
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How long can salmonella and E Coli survive on a hard surfa

Customer Question

How long can salmonella and E Coli survive on a hard surface?
Submitted: 6 years ago.
Category: Health
Expert:  DrOAB replied 6 years ago.

Hello from JustAnswer!


The survival time of these bacteria on hard, inanimate surfaces varies depending on ambient moisture and temperature, the surface material, and other factors. With regard to Salmonella, one study found a survival time in a toilet bowl of 4 weeks after the infected patient's diarrhea had stopped despite the use of cleaning fluids and up to 50 days' survival in an experimentally-contaminated toilet bowl (in contrast, normally dry areas, such as the toilet seat, flush handle, and bathroom doorknob, did not show such lengthy persistence). E. coli has been shown in a separate study to survive over 28 days at both refrigeration and room temperatures on stainless steel, but the bacteria only survived 90-360 minutes on surfaces of copper or copper alloy. In general, without bacteridal conditions or measures, both of these hardy bacteria appear to be able to survive on hard, inanimate surfaces for weeks.


Salmonella reference:

E. coli reference:

Edited by DrOAB on 6/11/2010 at 9:16 PM EST
Customer: replied 6 years ago.
I was a little more curious about kitchen counter tops, etc with bacteria from raw chicken or meat... would the time frames differ with those? And does raw meat automatically have these bacterias in it all the time?
Expert:  DrOAB replied 6 years ago.
Raw meat is not expected to automatically have such bacteria. As granite, wood, and other kitchen surfaces do not have inherent antibacterial qualities and are often exposed to moisture and organic particles, I would estimate a survival time of at least hours, if not weeks. I have to go offline now, but I can try to find medical research data giving a more exact estimate later, if you like.
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Customer: replied 6 years ago.
I would like that, if you don't mind.
Expert:  DrOAB replied 6 years ago.

Pathogenic bacteria, such as Salmonella and E.coli, can survive on kitchen surfaces for hours despite typical hygienic procedures.


Bacterial adhesion reference:


Moisture is a strong factor affecting bacterial survival on surfaces, especially for Salmonella, even on an outdoor granite outcropping.


Salmonella and moisture reference:

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