Prevalence and risk factors of Helicobacter pylori infection in military personnel: a systematic review and meta-analysis.

BACKGROUND AND AIMS: Helicobacter pylori infection is prevalent and recognized as a major cause of gastrointestinal diseases in the world. Previous studies on the prevalence of H. pylori infection in military personnel have shown some conflicting results. This study aimed to estimate the pooled prevalence of H. pylori infection and evaluate its risk factors in military personnel. METHODS: The PubMed, EMBASE, and Cochrane Library databases were searched. We pooled the prevalence of H. pylori infection in military personnel using a random-effect model. Metaregression analysis was used to explore the sources of heterogeneity. Pooled proportion of H. pylori infection with 95% confidence interval (CI) was calculated. RESULTS: Sixteen studies were included. Meta-analysis showed that the overall prevalence of H. pylori infection was 32% (95% CI = 31-33) in military personnel. There was a significant heterogeneity. Metaregression analysis showed that study region (P = 0.0004) and publication year (P = 0.023) were the potential sources of heterogeneity. In the subgroup analysis by study region, the highest prevalence was found in Asia (50.2%; 95% CI = 49-51.4). In the subgroup analysis by diagnostic methods for H. pylori, the highest prevalence was found when urea breath test was employed (47.9%; 95% CI = 46.5-49.3). The most common risk factor for H. pylori infection was familial aggregation, followed by living environment and age. CONCLUSION: H. pylori infection is common in military personnel. In future, we may require appropriate population screening for H. pylori infection by multiple diagnostic tests and increase the knowledge and awareness of the bacterial transmission among military personnel.

Chinese Consensus Report on Family-Based Helicobacter pylori Infection Control and Management (2021 Edition).

OBJECTIVE: Helicobacter pylori infection is mostly a family-based infectious disease. To facilitate its prevention and management, a national consensus meeting was held to review current evidence and propose strategies for population-wide and family-based H. pylori infection control and management to reduce the related disease burden. METHODS: Fifty-seven experts from 41 major universities and institutions in 20 provinces/regions of mainland China were invited to review evidence and modify statements using Delphi process and grading of recommendations assessment, development and evaluation system. The consensus level was defined as ≥80% for agreement on the proposed statements. RESULTS: Experts discussed and modified the original 23 statements on family-based H. pylori infection transmission, control and management, and reached consensus on 16 statements. The final report consists of three parts: (1) H. pylori infection and transmission among family members, (2) prevention and management of H. pylori infection in children and elderly people within households, and (3) strategies for prevention and management of H. pylori infection for family members. In addition to the 'test-and-treat' and 'screen-and-treat' strategies, this consensus also introduced a novel third 'family-based H. pylori infection control and management' strategy to prevent its intrafamilial transmission and development of related diseases. CONCLUSION: H. pylori is transmissible from person to person, and among family members. A family-based H. pylori prevention and eradication strategy would be a suitable approach to prevent its intra-familial transmission and related diseases. The notion and practice would be beneficial not only for Chinese residents but also valuable as a reference for other highly infected areas.

Primary and secondary clarithromycin resistance in Helicobacter pylori and mathematical modeling of the role of macrolides.

Clarithromycin is a macrolide antibiotic widely used for eradication of Helicobacter pylori infection, and thus resistance to this antibiotic is a major cause of treatment failure. Here, we present the results of a retrospective observational study of clarithromycin resistance (Cla-res) in 4744 H. pylori-infected patients from Central Hungary. We use immunohistochemistry and fluorescence in situ hybridization on fixed gastric tissue samples to determine H. pylori infection and to infer Cla-res status, respectively. We correlate this information with macrolide dispensing data for the same patients (available through a prescription database) and develop a mathematical model of the population dynamics of Cla-res H. pylori infections. Cla-res is found in 5.5% of macrolide-naive patients (primary Cla-res), with no significant sex difference. The model predicts that this primary Cla-res originates from transmission of resistant bacteria in 98.7% of cases, and derives from spontaneous mutations in the other 1.3%. We find an age-dependent preponderance of female patients among secondary (macrolide-exposed) clarithromycin-resistant infections, predominantly associated with prior use of macrolides for non-eradication purposes. Our results shed light into the sources of primary resistant cases, and indicate that the growth rate of Cla-res prevalence would likely decrease if macrolides were no longer used for purposes other than H. pylori eradication.

A comparative study of Helicobacter pylori infection in hamsters experimentally infected with liver flukes Opisthorchis felineus, Opisthorchis viverrini, or Clonorchis sinensis.

Helicobacter pylori causes a wide range of human diseases including cancer. Carcinogenic foodborne trematodes Opisthorchis viverrini, Clonorchis sinensis, and O. felineus might promote transmission and spread of H. pylori infection in the definitive mammalian host, which in turn might contribute to the liver fluke-associated malignancy. Our objectives were to find out whether liver flukes O. felineus, O. viverrini, and C. sinensis are carriers of Helicobacter pylori and to determine whether H. pylori is present in feces, bile, and stomach samples from the experimentally infected hamsters. We found that liver flukes are not reservoirs of H. pylori. Nevertheless, the prevalence of H. pylori and the H. pylori ureA gene copy number were significantly elevated after the infection. Overall, although the liver flukes O. felineus, C. sinensis, and O. viverrini are not reservoirs of H. pylori, the infection with the liver flukes significantly modifies the biliary and gut microbiota by increasing H. pylori abundance. This may be a feature of any liver fluke pathogenesis that have not previously been taken into account. Our findings appear to be novel in terms of comparative assessment of the host microbiota and Helicobacter abundance during epidemiologically important liver fluke infections.

Transmission of Helicobacter pylori between a human and two dogs: A case report.

BACKGROUND: Whereas non-Helicobacter pylori helicobacters, which are frequently detected in the stomachs of dogs and cats as a source of zoonoses, have attracted considerable attention, the role of pets in H. pylori epidemiology is unclear. In our previous study, an H. pylori infection was detected in the stomach of a dog (Dog 1). Here, we investigated the H. pylori infection status in the female offspring of Dog 1 (Dog 2) and its owner within the same household. MATERIALS AND METHODS: Biopsy specimens were obtained from the dog's owner and tested for H. pylori. DNA from gastric biopsy samples of Dog 1, gastric fluid sediment of Dog 2, and bacteria from the stomach of the owner was obtained, and Helicobacter genus- and species-specific PCRs were performed. Then, sequence analyses of the partial region of the ureAB gene were conducted. RESULTS: Samples from both dogs and the owner reacted positively in the genus-specific PCR and negative in the Helicobacter felis-, Helicobacter bizzozeronii-, and Helicobacter heilmannii sensu stricto-specific PCRs. All three samples also reacted positively in the H. pylori-specific PCR. Sequences of the partial ureAB gene from all subjects were identical. CONCLUSIONS: The results suggested that the two dogs and their owner were infected with an identical H. pylori strain. This report is the first to demonstrate that H. pylori can be transmitted between humans and dogs. Further studies are required to investigate the risk factors for the transmission of H. pylori between humans and dogs from the perspective of preventive epidemiology.

Helicobacter pylori knowledge and perception among multi-ethnic Asians.

BACKGROUND: Helicobacter pylori (HP) infection is endemic and causes peptic ulcer disease and gastric cancer. There is a lack of data related to awareness of the general public about HP and associated health risks. The objective of this study was to investigate the awareness and public perceptions about HP and the attitudes towards screening. METHODS: This cross-sectional study included a structured 19-item questionnaire targeting members of the general public at a restructured acute hospital in Singapore. RESULTS: Out of 504 participants, 152 (30.2%) were aware of HP. Higher education was associated with HP awareness (p < 0.001, OR 7.4, 95% CI 1.6-32.6). A third, 175 (34.7%) of the respondents identified the stomach as the primary site of infection. 131 (26.0%) respondents identified the fecal-oral route as a mode of transmission. 178 (35.3%) respondents were aware of available screening modalities, with around half of them willing to be screened with blood (n = 256, 50.8%) or breath tests (n = 265, 52.6%). 430 (85.3%) participants were keen to learn more about HP, and this was associated with age (p < 0.05, OR 3.9, 95% CI 2.1-7.1). CONCLUSION: Awareness about HP infection is low, and acceptance of screening tests is high. Educational efforts are needed to improve awareness.

Review: Epidemiology of Helicobacter pylori.

This review summarizes the recent knowledge on the epidemiology of Helicobacter pylori and the potential modes of transmission. In addition to English language publications, the authors have included original full-text publications from Russia and Latin America published in the original languages. High H pylori prevalence has been reported in Russia, Jordan, Iran, China, and Latin American countries as well as in Arctic populations in Canada. Indigenous inhabitants in the Arctic were found to be infected substantially more frequently than non-indigenous inhabitants. In Amsterdam, the Netherlands, the ethnic minority groups were at a significantly higher risk of being H pylori seropositive compared to the Dutch population. For the first time, data on the prevalence from Armenia have been published indicating 41.5% H pylori prevalence. Convincing evidence on the decline of H pylori prevalence in Southeast Hungary and Taiwan was published. A study from Chile suggested high infection rates in newborns during the first month after birth. Two meta-analyses covered the potential correlation between H pylori and periodontal diseases, therefore addressing the potential oro-oral transmission rates. Periodontal disease was found to be more prevalent in H pylori-infected subjects. Other studies addressed the potential role of drinking water and food products as well as socioeconomic factors in transmitting the infection. Several studies in Asia addressed annual reinfection rates of H pylori, ranging from 1.5% in China to 3.1% in Korea. Finally, a review was published on the current evidence and future perspective of analysing H pylori in ancient human remains by a metagenomic approach.

Individual and household correlates of Helicobacter pylori infection among Young Ethiopian children in Ziway, Central Ethiopia.

BACKGROUND: Investigating distinct individual- and household-level risk factors for acquiring Helicobacter pylori (H. pylori) infection can inform disease prevention efforts and implicate possible routes of transmission. This study determined the magnitude of H. pylori infection among schoolchildren in Ziway, central Ethiopia and identified personal and household correlates of H. pylori infection in young Ethiopian children. METHODS: A total of 434 schoolchildren participated in this cross-sectional study. Infection status was assessed using antigen and antibody rapid tests. Demographic and lifestyle information was obtained from parents via an interviewer-led questionnaire. Univariate and multivariate logistic regressions were performed to assess the relationships between potential individual- and household-level risk factors and H. pylori infection. RESULTS: The prevalence of H. pylori infection was 65.7% (285/434). Of the personal variables assessed, the age group 10-14 years was found to be significantly associated with higher odds of H. pylori infection in univariate analysis (COR = 2.22, 95% CI: 1.06-4.66, p = 0.03) and remained positively correlated after adjusting for confounding factors. Of the household-level factors explored, having a traditional pit or no toilet was found to be significantly associated with 3.93-fold higher odds of H. pylori infection (AOR = 3.93, 95% CI: 1.51-10.3, p = 0.01), while the presence of smokers in the household was associated with 68% lower odds of infection (AOR = 0.32, 95% CI: 0.11-0.89, p = 0.03). CONCLUSION: This study from a developing country provides additional evidence for older age as a personal risk factor for H. pylori infection and identifies correlations between socioeconomic and sanitation household factors and positive childhood infection status. The associations reported here support the hypothesized fecal-oralroute of transmission for H. pylori.

Natural Transmission of Helicobacter saguini Causes Multigenerational Inflammatory Bowel Disease in C57/129 IL-10-/- Mice.

Cotton-top tamarins (CTTs) are an ideal model of human inflammatory bowel disease (IBD) because these animals develop multigenerational, lower bowel cancer. We previously isolated and characterized a novel enterohepatic Helicobacter species, Helicobacter saguini, from CTTs with IBD and documented that H. saguini infection in germfree C57BL IL-10-/- mice recapitulates IBD, suggesting that H. saguini influences IBD etiopathogenesis. In this study, we utilized a germfree IL-10-/- model to illustrate that H. saguini infection can naturally transmit and infect four generations and cause significant intestinal inflammatory pathology. Additionally, whole-genome sequencing of representative H. saguini isolates from each generation of IL-10-/- mice revealed gene mutations suggestive of multigenerational evolution. Overall, these results support that specific bacterial species with pathogenic potential, like H. saguini, are transmissible microorganisms in the etiopathogenesis of IBD in CTTs and reinforces the importance of specific microbiota in the pathogenesis of IBD in humans.IMPORTANCE While family history is a significant risk factor for developing inflammatory bowel disease (IBD), it is unclear whether the microbiome from parents is a transmissible influence on disease in their offspring. Furthermore, it is unknown whether IBD-associated microbes undergo genomic adaptations during multigenerational transmission and chronic colonization in their hosts. Herein, we show that a single bacterial species, Helicobacter saguini, isolated from a nonhuman primate species with familial IBD, is transmissible from parent to offspring in germfree IL-10-/- mice and causes multigenerational IBD. Additionally, whole-genome sequence analysis of H. saguini isolated from different mouse generations identified microevolutions in environmental interaction, nutrient metabolism, and virulence factor genes that suggest that multigenerational transmission may promote adaptations related to colonization and survival in new hosts and chronic inflammatory environments. The findings from our study highlight the importance of specific bacterial species with pathogenic potential, like H. saguini, as transmissible microorganisms in the etiopathogenesis of IBD.

Global whole family based-Helicobacter pylori eradication strategy to prevent its related diseases and gastric cancer.

Helicobacter pylori (H. pylori) infects approximately 50% of the world population. The multiple gastrointestinal and extra-gastrointestinal diseases caused by H. pylori infection pose a major healthcare threat to families and societies; it is also a heavy economic and healthcare burden for countries that having high infection rates. Eradication of H. pylori is recommended for all infected individuals. Traditionally, "test and treat" and "screen and treat" strategies are available for various infected populations. However, clinical practice has noticed that these strategies have some shortfalls and may need refinement, mostly due to the fact that they are not easily manageable, and are affected by patient compliance, selection of treatment population and cost-benefit estimations. Furthermore, it is difficult to control infections from the source, therefore, development of additional, compensative strategies are encouraged to solve the above problems and facilitate bacteria eradication. H. pylori infection is a family-based disease, but few studies have been performed in a whole family-based approach to curb its intra-familial transmission and the development of related diseases. In this work, a third, novel whole family-based H. pylori eradication strategy is introduced. This approach screens, identifies, treats and follows up on all H. pylori-infected individuals in entire families to control H. pylori infection among family members, and reduce its long-term complications. This strategy is high-risk population-oriented, and able to reduce H. pylori spread among family members. It also has good patient-family compliance and, importantly, is practical for both high and low H. pylori-infected communities. Future efforts in these areas will be critical to initiate and establish healthcare policies and management strategies to reduce H. pylori-induced disease burden for society.

Pathogenesis and clinical management of Helicobacter pylori gastric infection.

Helicobacter pylori (H. pylori) is a gram-negative bacterium that infects approximately 4.4 billion individuals worldwide. However, its prevalence varies among different geographic areas, and is influenced by several factors. The infection can be acquired by means of oral-oral or fecal-oral transmission, and the pathogen possesses various mechanisms that improve its capacity of mobility, adherence and manipulation of the gastric microenvironment, making possible the colonization of an organ with a highly acidic lumen. In addition, H. pylori presents a large variety of virulence factors that improve its pathogenicity, of which we highlight cytotoxin associated antigen A, vacuolating cytotoxin, duodenal ulcer promoting gene A protein, outer inflammatory protein and gamma-glutamyl transpeptidase. The host immune system, mainly by means of a Th1-polarized response, also plays a crucial role in the infection course. Although most H. pylori-positive individuals remain asymptomatic, the infection predisposes the development of various clinical conditions as peptic ulcers, gastric adenocarcinomas and mucosa-associated lymphoid tissue lymphomas. Invasive and non-invasive diagnostic methods, each of them with their related advantages and limitations, have been applied in H. pylori detection. Moreover, bacterial resistance to antimicrobial therapy is a major challenge in the treatment of this infection, and new therapy alternatives are being tested to improve H. pylori eradication. Last but not least, the development of effective vaccines against H. pylori infection have been the aim of several research studies.

Colonization of Dental Unit Waterlines by Helicobacter pylori: Risk of Exposure in Dental Practices.

Dental unit waterlines (DUWLs) can be considered one of the possible routes of H. pylori transmission, although its presence in DUWLs has not yet been investigated thoroughly. The present study aimed to discover the prevalence of H. pylori and oral streptococci (S. oralis and S. mutans) in DUWLs to evaluate the risk of exposure to human pathogens in dental practices. We collected the output water from 60 dental chair units (DCUs) in 26 private dentistry settings in Turin, searching for H. pylori and oral streptococci (OS) DNA, with a polymerase chain reaction (PCR) technique. At the same time, dentists completed a questionnaire about their DCUs, their main activities, the presence of anti-retraction devices, their attitudes about disinfection, etc. No dental chair unit tested was contaminated with H. pylori or S. mutans; only one dental chair was contaminated with S. oralis (1.7%). Considering the results, we can state that: (i) the lack of H. pylori DNA in water samples analyzed, suggests that municipal water is presumably treated with a sufficient chlorine level to inactivate DNA over time; (ii) the aspiration of oral fluids is limited by anti-retraction valves fitted distally to hand pieces; (iii) propidium monoazide qPCR (PMA-qPCR) could be a good technique to investigate and monitor potential environmental sources of infections such as DUWLs.

Dinámica de la infección por Helicobacter pylori en lactantes durante los primeros 6 meses de vida / Dynamics of Helicobacter pylori infection in infants during the first six months of life

Introducción: Helicobacter pylori constituye un problema de salud mundial principalmente por el elevado porcentaje de infección y la ineficacia en los tratamientos. Para prevenir la infección resulta clave conocer la edad de adquisición. Pacientes: Participaron 67 madres y sus respectivos hijos. Para evaluar la presencia de H. pylori, las deposiciones de la madre y de su hijo fueron analizadas mediante el test HpSA. Resultados: El 71,6% (48/67) de las embarazadas a término fueron H. pylori positivas. En los recién nacidos, el 8,96% (6/67) de ellos presentaron colonización/infección persistente para H. pylori. Durante el primer mes de vida se observó una prevalencia e incidencia de infección del 23,9 y 13%, respectivamente. Conclusión: Los resultados, en conjunto, sugieren que durante el primer mes de vida existe un alto riesgo de infección por H. pylori, pudiendo ser esta incluso de tipo persistente

Introduction: Mainly due to the high percentage of infection and the ineffectiveness of treatments, Helicobacter pylori is a global health problem. Knowing the age at acquisition is key to preventing the infection. Patients: Sixty-seven mothers and their respective children participated. To evaluate the presence of H. pylori, the faeces of the mother and her child were analysed using the HpSA antigen test. Results: 71.6% (48/67) of pregnant mothers were positive for H. pylori at the term of their pregnancy. In newborns, 8.96% (6/67) of them showed H. pylori colonisation/persistent infection. During the first month of life, a prevalence and incidence of infection of 23.9% and 13%, respectively, was observed. Conclusion: Overall, the results suggest that there is a high risk of H. pylori infection during the first month of life, even of the persistent type

Dynamics of Helicobacter pylori infection in infants during the first six months of life. / Dinámica de la infección por Helicobacter pylori en lactantes durante los primeros 6 meses de vida.

INTRODUCTION: Mainly due to the high percentage of infection and the ineffectiveness of treatments, Helicobacter pylori is a global health problem. Knowing the age at acquisition is key to preventing the infection. PATIENTS: Sixty-seven mothers and their respective children participated. To evaluate the presence of H. pylori, the faeces of the mother and her child were analysed using the HpSA antigen test. RESULTS: 71.6% (48/67) of pregnant mothers were positive for H. pylori at the term of their pregnancy. In newborns, 8.96% (6/67) of them showed H. pylori colonisation/persistent infection. During the first month of life, a prevalence and incidence of infection of 23.9% and 13%, respectively, was observed. CONCLUSION: Overall, the results suggest that there is a high risk of H. pylori infection during the first month of life, even of the persistent type.

Helicobacter pylori, transmission routes and recurrence of infection: state of the art.

Helicobacter pylori (H. pylori) infection is one of the most common infection in humans, affecting more than half of the population. The prevalence of the infection varies widely in rural developing areas (more than 80%) compared to urban developed ones (less than 40%), as a consequence of different socioeconomic and hygienic conditions. H. pylori infection is usually acquired during childhood; infected people usually remain asymptomatic, but about 30% of individuals may develop mild to severe upper gastrointestinal diseases such as gastritis, peptic ulcer, gastric cancer or MALT lymphoma. The transmission route is not clear yet; the person-to-person transmission, especially within the same family appears to be prevalent, but also environmental contamination is possible. The eradication without a specific therapeutic regimen is very unlikely and the reinfection rate after an effective eradication therapy is quite rare. The reinfection rate will increase if there are family members affected.

Evaluating the origin and virulence of a Helicobacter pylori cagA-positive strain isolated from a non-human primate.

Helicobacter pylori cagA-positive strains are critically involved in the development of gastric cancer. Upon delivery into gastric epithelial cells via type IV secretion, the cagA-encoded CagA interacts with and thereby perturbs the pro-oncogenic phosphatase SHP2 and the polarity-regulating kinase PAR1b via the tyrosine-phosphorylated EPIYA-C/D segment and the CM sequence, respectively. Importantly, sequences spanning these binding regions exhibit variations among CagA proteins, which influence the pathobiological/oncogenic potential of individual CagA. Here we isolated an H. pylori strain (Hp_TH2099) naturally infecting the stomach of a housed macaque, indicating a zoonotic feature of H. pylori infection. Whole genome sequence analysis revealed that Hp_TH2099 belongs to the hpAsia2 cluster and possesses ABC-type Western CagA, which contains hitherto unreported variations in both EPIYA-C and CM sequences. The CM variations almost totally abolished PAR1b binding. Whereas pTyr + 5 variation in the EPIYA-C segment potentiated SHP2-binding affinity, pTyr-2 variation dampened CagA tyrosine phosphorylation and thus impeded CagA-SHP2 complex formation. As opposed to the H. pylori standard strain, infection of mouse ES cell-derived gastric organoids with Hp_TH2099 failed to elicit CagA-dependent epithelial destruction. Thus, the macaque-isolated H. pylori showed low virulence due to attenuated CagA activity through multiple substitutions in the sequences involved in binding with SHP2 and PAR1b.

Phenotypic analysis of antibiotic resistance and genotypic study of the vacA, cagA, iceA, oipA and babA genotypes of the Helicobacter pylori strains isolated from raw milk.

Background: Foods with animal origins and particularly milk play a considerable role in transmission of Helicobacter pylori. The current study was performed to assess phenotypic characters of antibiotic resistance and genotyping pattern of vacA, cagA, iceA, oipA and babA2 alleles amongst the H. pylori strains isolated from raw milk. Methods: Six-hundred and thirty raw milk samples were collected and cultured on Wilkins Chalgren anaerobe media. Antibiotic resistance and genotyping patterns were studied using disk diffusion and PCR, respectively. Results: Sixty-seven out of 630 (10.63%) raw milk samples were positive for H. pylori. Ovine raw milk (17.27%) samples had the highest prevalence of H. pylori, while camel (5.00%) had the lowest. H. pylori strains harbored the highest prevalence of resistance against ampicillin (82.08%), tetracycline (76.11%), amoxicillin (74.62%), metronidazole (65.67%) and erythromycin (53.73%). Prevalence of resistance against more than 10 types of antibiotics was 17.91%. VacA s1a (83.58%), m1a (80.59%), s2 (77.61%) and m2 (68.65%), cagA (73.13%) and babA2 (44.77%) were the most commonly detected genotypes. We found that S1am1a (56.71%), s2m1a (56.71%), s1 am2 (43.28%) and s2 m2 (43.28%) were the most commonly detected genotyping pattern. Frequency of cagA-, oipA- and babA2- genotypes were 26.86%, 62.68% and 55.22%, respectively. We found that S1a/cagA+/iceA1/oipA-/babA2- (28.35%), m1a/cagA+/iceA1/oipA-/babA2- (28.35%) and s2/cagA+/iceA1/oipA-/babA2- (26.86%) were the most commonly detected combined genotyping pattern. Conclusions: Simultaneous presence of vacA, cagA, iceA, oipA and babA2 genotypes in antibiotic resistant H. pylori strains indicates important public health issue regarding the consumption of raw milk. However, additional researches are required to find molecular genetic homology and other epidemiological aspects of H. pylori in milk.

Helicobacter pylori: A foodborne pathogen?

Helicobacter pylori (H. pylori) is an organism that is widespread in the human population and is sometimes responsible for some of the most common chronic clinical disorders of the upper gastrointestinal tract in humans, such as chronic-active gastritis, duodenal and gastric ulcer disease, low-grade B-cell mucosa associated lymphoid tissue lymphoma of the stomach, and gastric adenocarcinoma, which is the third leading cause of cancer death worldwide. The routes of infection have not yet been firmly established, and different routes of transmission have been suggested, although the most commonly accepted hypothesis is that infection takes place through the faecal-oral route and that contaminated water and foods might play an important role in transmission of the microorganism to humans. Furthermore, several authors have considered H. pylori to be a foodborne pathogen because of some of its microbiological and epidemiological characteristics. H. pylori has been detected in drinking water, seawater, vegetables and foods of animal origin. H. pylori survives in complex foodstuffs such as milk, vegetables and ready-to-eat foods. This review article presents an overview of the present knowledge on the microbiological aspects in terms of phenotypic characteristics and growth requirements of H. pylori, focusing on the potential role that foodstuffs and water may play in the transmission of the pathogen to humans and the methods successfully used for the detection of this microorganism in foodstuffs and water.

Helicobacter pylori infection in family members of patients with gastroduodenal symptoms. A cross-sectional analytical study.

BACKGROUND: Primary Helicobacter pylori (H. pylori) infection is acquired predominantly in childhood in the family setting. We aimed to investigate the presence of intrafamilial concurrent H. pylori infection. DESIGN AND SETTING: Cross-sectional analytical study with a control group, conducted in a tertiary care hospital. METHODS: Fifty adult patients with gastroduodenal symptoms who underwent gastroscopy (index parents), their spouses and their children were enrolled in the study. Blood samples were collected from all of the study subjects to test for immunoglobulin G (IgG) antibody response. H. pylori antigen was investigated in the stool specimens of children only. RESULTS: The participants were divided into two groups: Group 1 consisted of the 40 patients in whom H. pylori infection was demonstrated via endoscopy, their spouses and their children. Group 2 included the remaining 10 patients who underwent endoscopy revealing negative results for H. pylori, their spouses and their children. IgG antibodies were present in all of the index parents, 95% of their spouses and 93% of their children in group 1; 13 of the children (9%) were also positive for H. pylori stool antigen (HpSA). However, IgG antibodies were present in only 2 of the 10 index parents in group 2. One of their spouses and one of their children had a positive antibody response. All of their children had negative stool antigen test results. CONCLUSION: H. pylori infections exhibit intrafamilial clustering. Parental infection, age ≥ years and having three or more siblings are the major risk factors for H. pylori infection in children.

Relating Phage Genomes to Helicobacter pylori Population Structure: General Steps Using Whole-Genome Sequencing Data.

The review uses the Helicobacter pylori, the gastric bacterium that colonizes the human stomach, to address how to obtain information from bacterial genomes about prophage biology. In a time of continuous growing number of genomes available, this review provides tools to explore genomes for prophage presence, or other mobile genetic elements and virulence factors. The review starts by covering the genetic diversity of H. pylori and then moves to the biologic basis and the bioinformatics approaches used for studding the H. pylori phage biology from their genomes and how this is related with the bacterial population structure. Aspects concerning H. pylori prophage biology, evolution and phylogeography are discussed.