MAP in the Environment
MAP in Food
MAP IN THE ENVIRONMENT:
MAP in Water
Mycobacterium avium subspecies paratuberculosis (MAP), which causes Johne's
Disease in many species of ruminants, is endemic in the food animal herds of
almost every developed country.
Since MAP is not classified as a human pathogen, meat, milk and other products from animals infected with MAP may be continually entering the human food chain. There is a wealth of evidence which appears to indicate that MAP
is capable of surviving the food
processing methods that we employ to protect us from disease, such as cooking
and pasteurization. This scientific evidence is thoroughly reviewed and
discussed in the MAP in dairy products,
MAP in beef products, and
Marshfield Clinic Study - Retail Testing
sections of our website.
Another possible route of transmission of MAP from cattle to humans is via
contaminated water supplies. This is because MAP is shed onto pastures and
will be washed off into ground and river waters. Where such water is piped
to households for human consumption, it may enable MAP to infect people
by this route as well.
Several other provocative questions must be answered:
- Is MAP-infected water used to irrigate crops?
- Could fruits and vegetables be contaminated in
processing plants where they are rinsed with MAP-infected water and processed for distribution to the
- Are we exposing our children to this pathogen by giving them fruit and
vegetables contaminated with MAP as a result of this process?
* * * * * * * *
The public deserves answers to these
very serious questions!
* * * * * * * *
Studies Being Conducted in the UK
The UK has taken the lead in
conducting studies relating to MAP infection in water supplies. At the
present time there are two studies underway. Sponsoring these
- Natural Environment Research Council's Centre for Ecology and Hydrology (CEH) - Funded by
Medical Research Council (MRC) and National
Environment Research Council (NERC) - Research Conducted by Professor Roger
Pickup (CEH, Windemere) and
Professor John Hermon-Taylor
(St. George's Hospital Medical School, London
- Department of Food Science, Queen's University Belfast - Research
Conducted by Whan LB, Grant IR, Ball HJ, Scott R., Rowe UT. (Lett
Appl Microbiol 2001 Sep;33(3):227-31)
The research being conducted at Natural Environment Research Council's Centre for Ecology and Hydrology (CEH) by Professors Pickup and Hermon-Taylor, a five-year study, began in
October, 2000. Overall, there are three co-operative projects within the
collabortive program of research. They are evaluating whether runoff from
cow pastures is contaminating drinking water supplies with MAP.
Quoting these researchers in an article printed in the IA Journal:
"...Taken together, the results of this new research, will permit the design and
implementation of measures to ensure that our animals are MAP-free, that our
water is safe, and perhaps through vaccine production, that the risk of Crohn's
disease is eventually eliminated."
The research completed and published in September 2001 at the Department of Food Science, Queen's
University Belfast relates to the bactericidal effect of chlorine on MAP in
drinking water. The study's aim was:
"To determine whether this
organism [MAP] can survive standard water treatment processes." Two
strains of M. paratuberculosis were subjected to various chlorine
The conclusion: "The data showed that when initial inoculum levels were high,
neither M. paratuberculosis strain was
completely killed at the free chlorine concentrations and contact times
applied." [underline added for emphasis]
Further, "This work highlights the need for further research
into the survival of M. paratuberculosis during water treatment."
In light of this study which concludes that MAP survives standard water
treatment processes, PARA urges immediate resesarch to ensure the protection of
the public health!
What is being done in the U.S.?
Sadly, the U.S. is doing nothing to ascertain: (1)
Extent of MAP-infection of public water supplies; (2) Whether water used
for crop irrigation is contaminating these food supplies; (3) What methods of
water treatment will ensure killing of MAP, and ultimately employing those
methods until such time that Johne's disease is eradicated from herds.
The Environment Protection Agency (EPA)
is the U.S. agency responsible for
the safety of water. They are aware of the problem as evidenced by
an August 1999 document entitled "Mycobacteria: Health Advisory".
(See Pages 4, 18-20)
Unfortunately, the U.S. is choosing to ignore the food AND water problems created by MAP in our environment. MAP is
on EPA's radar screen as an NTM, "Non-Tuberculosis Mycobacteria", yet they are
taking no action to protect the public by conducting research in this area or
issuing warnings to consumers.
Every U.S. citizen should be asking them WHY?
(See PARA's Governments subsection on the EPA
for further details
about this agency and its responsibilities in this area.)
While it is possible for individuals to eliminate milk/dairy/beef products
from their diet in an attempt to limit MAP exposure, it is nearly
impossible to avoid drinking MAP-contaminated water from public water
supplies, and equally as difficult to avoid foods that have potentially been
infected with MAP via irrigation methods using infected water.
There is an urgent need to determine what water treatment methods may be
effective at eliminating MAP from water supplies. We applaud the UK
researchers for their extremely important work in determining the extent of
MAP infection in public water supplies, and researching the efficacy of
treatment methods to ensure killing of this dangerous pathogen.
PARA is hopeful that the quote taken from Professor Pickup and Professor
Hermon-Taylor holds true: "The results of this new research, will
permit the design and implementation of measures to ensure that our animals are
MAP-free, that our water is safe, and perhaps through vaccine production, that
the risk of Crohn's disease is eventually eliminated."