The bacteria
H. pylori was first discovered in 1875 by German scientists
In 1980, Barry Marshall ingested the bacteria to prove it was infectious.
the National Institutes of Health USA (NIH) published its statement in 1994 that most recurrent gastric ulcers were
caused by H. pylori, the NIH recommended antibiotics be included in the treatment regimen for ulcers

/He·li·co·bac·ter/ (hel?i-ko-bak´ter) a genus of gram-negative, microaerophilic bacteria of the family Spirillaceae; H.
cinae´di causes proctitis and colitis in homosexual men and has been implicated in septicemia in neonates and
immunocompromised patients; H. pylo´ri causes gastritis and pyloric ulcers and has been implicated in gastric

Helicobacter genus : Helicobacter pylori is the leading cause of peptic ulcers and chronic gastritis in America.

Helicobacter pylori and Other Enteric Bacteria in Freshwater Environments in Mexico City

Helicobacter pylori infection is common in the Mexican population; however, sources, routes, and risk factors for
infection as well as mode of transmission remain unclear.

H. pylori was detected by polymerase chain reaction (PCR) technique in three aquatic systems located in the Mexico
City area. In addition, microbiologic cultures and physicochemical parameters were measured. The systems were
sampled over an 18-month period (1997–1999), resulting in a total of 212 samples for the different analyses.

Twenty-one percent of the samples (16/77) were positive for H. pylori; of these, 42% (5/12) were confirmed for cagA
gene detection by PCR hybridization. Microbiologic samples (n = 74) yielded Aeromonas hydrophila, Aeromonas caviae,
Aeromonas veronii, and Vibrio fluvialis. In the samples for physicochemical analyses (n = 61), low concentrations of
dissolved oxygen were detected and residual chlorine was less than the inactivation dose, both providing conditions for
potential survival of H. pylori and other enteric pathogens in these environments.

The results of this study suggest that, in Mexico City, water used for human consumption and irrigation may play an
important role as a vehicle in the transmission of H. pylori as well as infection by other known enteric pathogens.

2001, Transmission of Helicobacter pylori : a role for food? Bulletin of the World Health Organization, 2001, 79: 455–460.

Helicobacter pylori colonizes and grows in human gastric epithelial tissue and mucus. Its presence is associated with
gastritis and there is substantial evidence that it causes peptic and duodenal ulcers and chronic gastritis. Since
1994, H. pylori has been classified as carcinogenic to humans.
In industrialized countries, as many as 50% of adults are infected with the pathogen, while in the developing
world, prevalence values of about 90% have been reported. As little is known about the mode of transmission, a
literature search was carried out to determine whether food acts a reservoir or vehicle in the transmission of
H. pylori. Although growth of the pathogen should be possible in the gastrointestinal tract of all warm-blooded
animals, the human stomach is its only known reservoir. Under conditions where growth is not possible, H. pylori
can enter a viable, but nonculturable state. H. pylori has been detected in such states in water, but not in food.
Person-to-person contact is thought to be the most likelymode of transmission, and there is no direct evidence that
food is involved in the transmission of H. pylori. -- H. pylori only grows at temperatures of 30–37 oC. All
the required growth conditions are met in the gastrointestinal tract of all warm-blooded animals. At temperatures below
30 oC, H. pylori could survive in some foods, such as fresh fruit and vegetables, fresh poultry or fish, fresh meats, and
some dairy products (23). H. pylori survived at 30 oC in laboratory media (22), water (17), and milk (24), and survived
longer at lower temperatures (22).

2001, Presence of Helicobacter pylori in Drinking Water is Associated with Clinical Infection
Helicobacter pylori was detected using molecular methods in untreated well water. The presence of H. pylori in the wells
correlated with infection in consumers and with the presence of Escherichia coli, indicating fecal contamination.
Consumption of untreated well water should be considered a risk factor for H. pylori infection. --- Although Helicobacter
pylori colonizes \50% of the world’s population, no reservoir outside of the human stomach has been identified.
Transmission presumably occurs through fecal–oral and oral–oral routes. An epidemiological association between water
sources and the prevalence of H. pylori infection has been identiŽ ed (1–3). Further evidence for water as a vehicle for
transmission has been provided by culture of H. pylori from the feces of infected individuals (4), maintenance of viability
in water (5), amplification of H. pylori-specific nucleic acid sequences in water (6–8) and detection of actively respiring
H. pylori in surface and groundwater (9). In the course of a survey of private untreated well water in Pennsylvania,
USA, we found a signiŽ cant association between the presence of H. pylori and clinical infection in individuals drinking
the water.
K. H. Baker, EnØironmental Microbiology Research Laboratory, Penn State Capital College, TL 105, 777 W. Harrisburg
Pike, Middletown, PA 17057, USA

2002 Isolation and Genotyping of Helicobacter pylori from Untreated Municipal Wastewater
Yingzhi Lu,1 Thomas E. Redlinger,1* Raquel Avitia,1 Adriana Galindo,1
and Karen Goodman2
Department of Biological Sciences, University of Texas, El Paso, Texas 79968,1 and
Houston School of Public Health, University of Texas, Houston, Texas 779022
Received 10 October 2001/Accepted 17 December 2001

For this study, we isolated Helicobacter pylori from wastewater by a series of steps beginning with immunomagnetic
separation and cell culture. After Gram staining and three standard microbial tests, the 16S rRNA
sequences of a total of 23 out of 37 putative H. pylori isolates were verified by PCR. Eleven H. pylori isolates were
genotyped and fell into four vacA classes: those with the vacA allelic variants s1a and m1, s1b and m1, s2 and
m2, or s2 and m1. Most H. pylori isolates were of the vacA s1a/m1 type, which has been shown to be associated
with advanced diseases based on genotyping of H. pylori from gastric cancer patients. These results demonstrated
that H. pylori survives in water and may be a potential source of H. pylori transmission, especially where
water is not adequately treated.

Helicobacter pylori, a Gram-negative, microaerophilic bacterium, has been implicated in the etiology of most gastritis and
duodenal ulcers and is believed to play a role in gastric cancer (3). Water supplies contaminated with fecal material may
be a potential source of H. pylori transmission (13). This is particularly relevant in developing countries where municipal
water supplies are not adequately treated and water is obtained from rivers and other untreated sources (9, 15, 19).
Although no evidence of association of human infection with water source has been reported in the United States, H.
pylori has been detected in sewage, surface water, and shallow groundwater by various methods (11–13; K. Forrest, M.
Stinson, and S. M. Wright, Abstr. 98th Gen. Meet. Am. Soc. Microbiol., abstr. Q-48, p. 445, 1998).

2002, Determining antibiotic resistance in Helicobacter pylori
Sandra Hjalmarsson, Maria Sjölund, Lars Engstrand

Resistance development is a significant clinical problem in Helicobacter pylori and represents the major cause of
treatment failure. Today the problem is most focused on the macrolide clarithromycin that is an essential component of
the H. pylori treatment. Traditional methods for resistance determination, e.g., disc diffusion tests or E-tests, could in the
next 5 years be replaced by DNA-based methods. The most commonly used molecular methods available today are not
used in the daily routine work. Rapid and reliable DNA-based methods for prediction of antimicrobial resistance
phenotype are currently available within research. As fabrication costs reduce and validated targeted assays are
developed with easy hands-on procedures, it is most likely that such assays will become important tools for clinical
diagnosis of resistant H. pylori strains.

2004, Detection of free and plankton-associated Helicobacter pylori in seawater.

Aims: To detect both free and plankton-associated Helicobacter pylori in seawater samples collected on the Italian
coast of the Adriatic Sea using a nested-PCR.

Methods and Results: Dissolved oxygen, pH, salinity and chlorophyll a were the parameters recorded together
with the characterization of zooplanktonic organisms. Plankton-associated H. pylori DNA was searched for in water
samples filtered through 200 and 64 lm nylon nets whereas free bacteria were retained with the subsequent
filtration through 0Æ22 lm pore-size membranes. Nested-PCR using primers for the glmM (ureC) gene was
performed to reveal the presence of H. pylori. The DNA sequencing of amplified products confirmed the specificity
of the assay. The sensitivity of the nested-PCR assay for H. pylori detection was 62 CFU per 100 ml in spiked water
samples. Helicobacter pylori either free or bound to planktonic organisms was found in seven of 12 monthly samples.
In particular, free bacteria were detected during the summer sampling and in November, December and March
associated to planktonic cells.

Conclusions: The presence of free and plankton-associated H. pylori in seawater suggests that it can be a
significant reservoir and a potential route of transmission for the microorganism.
Significance and Impact of the Study: Our study seems to provide a promising background to define new and
effective strategies for surveillance of this human pathogen.

19 August 2005

Parkinson's disease linked to H. pylori infection
Parkinson's disease may be associated with the peptic ulcer causing bacterium Helicobacter pylori, say researchers who
found that eradication of the bacterium significantly improves certain physical abilities in people with the neurological

Parkinson's disease is a degenerative brain disorder in which neurons in a specific area of the brain become
dysfunctional. Symptoms of Parkinson's disease include tremors, muscular rigidity or stiffness, slowness of movement,
balance problems and difficulties with handwriting and other forms of communication such as speech and facial

Writing in the journal Helicobacter, Dr Inguar Bjarnason, from Guy's, King's and St. Thomas' School of Medicine in
London, UK, and colleagues explain that previous research suggests that many people with Parkinson's disease have a
prior diagnosis of peptic ulcer, but the relationship between this stomach condition and the development of Parkinson's
disease is not known.

For their study, the researchers compared the severity of Parkinson's symptoms, such as poor muscular function, in
seven patients who received active treatment for H. pylori infection and 11 patients who received a dummy treatment

The results indicated that there was a greater improvement in walking stride-length in the Parkinson's patients who
received treatment for H. pylori infection than in those who received placebo, the majority of whom showed reductions in
stride length.

The degree of muscle rigidity in the forearms was also reduced in patients who underwent H. pylori treatment, compared
with those who took placebo.

The researchers conclude that the eradication of H. pylori halts the production of toxins by the bacterium, "which may
have caused cumulative damage over decades", therefore improving some aspects of physical functioning in people
with Parkinson's disease.

They add that more studies are needed to investigate the relationship between infection with H. pylori and other micro-
organisms and the development of Parkinson's disease further.

Health Canada

Helicobacter pylori, formerly known as Campylobacter pylori, was first recognized as a human pathogen in 1983
(Postius, 2001) and was subsequently identified as a human carcinogen by the International Agency for Research on
Cancer (IARC, 1994).

Two morphologically distinct forms of H. pylori, a spiral shape and a coccoid form, have been identified (van Duynhoven
and de Jonge, 2001). The spiral shape is cultured routinely from clinical samples. To date, the coccoid form has been
found to be non-culturable. Transformation from the spiral-shaped bacterium grown in culture to the non-culturable
coccoid form is thought to result from variations in the environment, such as oxygen stress, temperature changes, the
presence of antibiotics, and other stress-inducing conditions (Engstrand, 2001). At present, it is still unclear whether the
coccoid form is viable but non-culturable (VBNC), similar to VBNC states found with Salmonella, Campylobacter, and
Vibrio spp. (Byrd et al., 1991), and therefore able to infect humans, or if it is simply non-viable (van Duynhoven and de
Jonge, 2001). Attempts to revert the coccoid form to the spiral form using nutrient supplementation (Sörberg et al.,
1996) have been unsuccessful. Reversion has been successful in only one report, using mice (Wang et al., 1995).
Attempts to use the same procedure in pigs resulted in contradictory results (Eaton et al., 1995).

[Why would the following conflicting statement be in the paragraph?]

H. pylori has not yet been isolated from environmental sources, including water. However, other methods have
been able to detect H. pylori. For example, it has been found microscopically, using a fluorescent antibody, in surface
waters and shallow groundwaters (Hegarty et al., 1999). Molecular methods, such as polymerase chain reaction, have
also been used to detect the presence of H. pylori DNA in water (Enroth and Engstrand, 1995). Under laboratory
conditions, H. pylori has been shown to survive for days, up to weeks, in sterile river water, saline solution, and distilled
water at a wide variety of pH levels and in temperatures ranging from 4°C to 15°C (West et al., 1992; Shahamat et al.,
1993). These results indicate that water may be a potential source of transmission for H. pylori. Currently, the only
substantial reservoir of H. pylori has been found to be the human stomach (Dunn et al., 1997). Domestic cats have been
found to harbour the organisms, but studies conducted have been unsuccessful at linking pet ownership with H. pylori
seropositivity (Webb et al., 1996b; Bode et al., 1998). The bacterium has also been isolated from primates, but, due to
rare contact, primates are unlikely to be important reservoirs.

EPA -- 2008 Progress Report: Rapid and Quantitative Detection of Helicobacter Pylori and E. Coli O157 in Well Water
Using a Nano-Wired Biosensor and QPCR

Key results and findings of the qPCR development: (1) Rapid qPCR methods have been developed for two fecal
indicators E.coli and Enterococci and two pathogens Helicobacter and E.coli 0157H7; (2) qPCR has been used to detect
Helicobacter in sewage and detects what is likely the viable non-cultivatible state (previous report and publication); and
(3) qPCR is highly correlated to E.coli and Enterococci in sewage but this same assay does not detect all of the species
present in manure, either due to interferences or more likely due to specificity of the primers. A detailed report is
presented in Appendix 1

2011, Optimal Therapy for Helicobacter pylori Infections: Developing Countries
The majority of the world's population is infected with H. pylori (a class I carcinogen); the highest burden of infection
occurs in developing countries, where it is estimated that 70-95% of adults are infected.[78] Developing countries also
carry the largest burden of diseases associated with H. pylori, such as gastric cancer.[79] Although gastric cancer has
declined in developed countries in recent decades, it remains one of the most common cancers worldwide.[79,80]
Furthermore, owing to its dismal prognosis, gastric cancer is the second most frequent cause of cancer mortality with a
rate of 803,000 deaths per year, primarily in developing countries.[79] Projections by the WHO predict that the
proportion of deaths caused by cancer will increase dramatically in the coming decades, and gastric cancer is projected
to become one of the 10 leading causes of death overall worldwide by 2030.[80]