Foodborne Pathogens: Where Have We Been and Where Are We Going?
Foodborne Pathogens: Where Have We
Been and Where Are We Going ?
Michael G. Johnson, Ph.D.
Emeritus Prof., UAF Food Science Dept.
AAFP Meeting, Sept. 10-11, 2013
What is our goal -- Food Safety or Food
Protection & What does that mean??
• From whence did IAFP and our AAFP come ?
• Early history of IAFP was in milk processing
technology and safety and the society name
evolved to IAMFES-- What’s that stand for ?
• Intnl Assoc Milk, Food, and Environmental
• In 2000 that acronym morphed to IAFP =
Intnl Assoc for Food Protection
Where are the hurts in Food Safety &
• Produce Safety Issues • Animal Food Safety
Quotes about Thinking
• J. Swift:
“ It is useless to attempt
to reason a man out of
a thing he never
reasoned into. “
• J. P. Moynihan:
“ Everyone is entitled to
his own opinion but not
to his own facts “
Lately I’ve Been Thinking…
• Our Modern Dilemma:
• Mo Jo: More Doing …
• More cell phone
• Less thinking
• One Solution:
• Less Doing …. More
• e. g., More quiet times
w/o cell / tablet
interruptions and more
manual hands-on labor
& walking to give quiet
• More thinking, Try It !
So, where are we presently ?
• Molecular Era of Food
• Q: Are we drowning in
a sea of chemical data ?
• PCR gel slide: What
does it tell us and not
tell us ?
• Ditto Q for CLAMP
patterns known as PFGE
patterns used by CDC to
link foods and
pathogens involved in
human FBI cases ?
• Sequencing coming on-
e.g. , Silliker Labs, etc.
W. E. Deming: Quality Assurance to
Continuous Quality improvement :
• Check Study
• Maybe, it’ s time to shift the paradigm from
asking the microbes to read our laws and
instead re-start reading, studying & learning
the playbooks of the microbes
Q: What food safety era have we been
• A: We have been copying the tenets of
Deming for auto manufacturing:
• Namely, we have moved from Quality Control
Model: ( = Is the finished food product ok in
quality, microbiology and chemistry and
nutritional aspects ? to ------>
• The Quality Assurance model: ( = Is every step
from starting raw product and ingredients and
every processing step ok ? = HAACP )
Still we continue to have cases of
human FBI– Why and What to Do ??
• Washington, DC’s answer is : Let’s write more
laws and regulations “ that will give us more
food safety “
• But, even with more laws we still seem to keep
having human FBI and food safety issues arise --
• Could it be that our dumb old foodborne
pathogens do not care and do not read our dumb
• $ for training & monitoring ( Fd Saf Ed Mini-Symp)
Maybe, just maybe we need to step
back and re-think what we are doing:
• Does it make scientific sense from first
principles to legally declare:
• Red meat carcasses with EHEC or Salmonella
are not “ adulterated “
• But raw trim and raw ground beef from those
carcasses with EHEC or Salmonella are
“ adulterated “ ?
Similarly, for poultry product
processing we can ask:
• Does it make sense to legally declare that:
• Poultry farms and flocks with Salmonella are
not adulterated and are not subject to federal
inspection or regulation but
• Raw ground poultry with Salmonella from
those flocks is adulterated ?
What is the trouble here ?
• Could it be that we are still stuck in the old
paradigm of Quality Control = equals if the door
on the car does not fit at the end of the assembly
line we condemn the whole car
• Have we been lulled to sleep and so do not see
that we truly do not yet have Quality Assurance
as our Mo Jo = we have not demanded that the
starting & intermediate steps of food processing
be as free of pathogens as possible ?
What is microbial food safety &
• MGJ’s answer is:
• Everything that impacts the safety of my:
– Food both plant and animal sources
Who knows the “ parable of the lost car keys “ ?
What era are we heading into- How do
we get to the Quality Assurance model
of food safety ?
• We need to head toward rediscovering the
tenets of microbial ecology and whole cell
• Namely, how do the indigenous microflora on
food plants and in food animals affect the
persistence of undesirable foodborne
pathogens on and in foods from those
What is the key here ?
• Besides using our evolving molecular tools we
need to get a better understanding of
“ Microbiomes” , namely how the native
microflora on food plants affects the survival
and persistence of foodborne pathogens , e.g.
Listeria monocytogenes on cantaloupe or
Salmonella, EHEC and now Cyclospora on
lettuce and spinach, etc. IN THE FIELD .
Similarly for food animals:
• We need to look at the indigenous
microbiomes in the GI tracts of our food
animals to see what their effects are on the
persistence of foodborne pathogens
• What kinds of interactions are going on in the
host GI tract between the native microbiota
and the invading pathogens ??
Finally, for man kind, what can we do ?
• We can look at the effects of the microbiome
in the GI tract of humans as a function of age,
dietary choices, general nutritional status and
genetics on the persistence of foodborne
pathogens in those GI tracts and ability to
cause cases of FBI.
Who can do all this ?
• In 1984 when I joined the UAF faculty there
were two faculty with some food safety
assignment, namely, to my recall:
• Dr. Mike Slavik in Animal & Poultry Science
• MGJ in the Food Science Dept.
• MGJ pestered UAF Admin for more food safety
researchers and ….
Slowly, other Food Safety Researchers
have been hired into the Food Science
Dept. to work on the pathogens &
microbiomes that affect man:
• 2005, Steve Ricke, Wray Chair of Food Safety and Dir.
Of Center for Food Safety: Pathogens impacting the
safety of animal food products
• 2012, Kristen Gibson : Noroviruses, environmentally
transmitted pathogens impacting the safety of food
• 2013, Franck Carbonero: Microbes in human GI tract
that impact Gut Health and Nutritional Status
What is the take home message ?
• My conclusion is:
• We need to head up stream to gain a better
understanding of how Mother Nature does
what she does and where she does it as it
concerns the microbes, their existence,
persistence, and preferred niches in Nature.
• What is your game plan ? Let’s talk about it.
• What are your hypotheses ?