1
DEVELOPMENT AND APPLICATION OF A PLATING MEDIA FOR DETECTION
OF HELICOBACTER PYLORI IN WATER
Alan J. Degnan*, Jon H. Standridge
Environmental Health Division
Wisconsin State Laboratory of Hygiene
2601 Agriculture Dr.
P.O. Box 7996
Madison, WI 53707-7996
ABSTRACT
In the U.S. alone, about 5,000,000 people are diagnosed annually with ulcers,
1,000,000
are hospitalized, 40,000 undergo surgery, and 6,500 die from ulcer-related
complications (Poms,
2001: Levin, 1998). Once thought to be a result of stress and/or diet, ulcers
are now almost
exclusively attributed to infection with the bacteria Helicobacter pylori.
Laboratory diagnosis of
H. pylori has become a standard procedure in the management of dyspeptic
patients. Although
transmission of the organism through the fecal/oral route is the assumed
infection route, the
possible mechanisms of human infection such as food, person to person contact,
water or fomites
are not clearly understood. There are a few reports in the literature suggesting
transmission of
H. pylori to humans via groundwater (Hegarty, 1999; Hulten, 1995 & 1998).
Methods of
detection used in those studies were relatively complex and costly (polymerase
chain reaction;
immunomagnetic separation) and unfortunately, didn't determine if the detected
organisms were
in fact viable or infectious. The work reported here focused on the development
of a
microbiological plating media that selects viable H. pylori organisms from
samples containing
mixed microbial populations, which could then be used for routine screening
of ground and/or
surface water for the presence of H. pylori. Efforts have resulted in a media
formulation that
allows the growth of Helicobacter while subsequently excluding common waterborne
microbial
background contaminants such as gram positive cocci and bacilli, enterobacteriaceae,
gram
negative bacilli, fungi, and pseudomonads. The laboratory-tested plating
media was used to
survey a cross section of Wisconsin groundwaters to further evaluate the
efficacy of the media
for recovering H. pylori from water samples and to begin a data base of H.
pylori occurrence.
INTRODUCTION
A scientific breakthrough occurred in 1982 when J. R. Warren and B. Marshall
isolated a
bacterium and showed that it caused gastritis and stomach ulcers that affect
millions of humans
worldwide (Marshall, 1984). Today that claim has been proven to the extent
that the National
Institute of Health recommends treatment with antibiotics for all patients
with peptic ulcers,
which are almost exclusively attributed to infection with the bacteria Helicobacter
pylori
(Graham, 1991). The scope of gastric illnesses around the world is vast.
In the U.S. alone,
estimates as high as 50% of adult Americans carry the pathogen, most asymptomatically,
and in
less-developed countries human carriers represent up to 90% of the populations
(Munangi,
1997).
The source of human infection is not yet known and until recently, the natural
reservoir
for H. pylori was thought to be the human gastrointestinal tract (Axon, 1996).
However,
isolation of Helicobacter from non-human sources such as livestock (Vaira,
1992), domestic cats