Pylori Transmission Research Articles

Whole-genome sequencing analyses and antibiotic resistance situation of 48 Helicobacter pylori strains isolated in Zhejiang, China

PurposeIn the Zhejiang region, research on Helicobacter pylori is lacking. The purpose of this study was to assess the extent of antibiotic resistance in H. pylori in this region, explore alternative methods for predicting the resistance patterns of H. pylori, and investigate the colonization of native gastric mucosa by other clades of H. pylori in the structure population of this bacterium.MethodsStrains were cultured under microaerobic conditions, and antimicrobial susceptibility testing (AST) was performed via agar dilution. Whole-genome sequencing (WGS) was performed via next-generation sequencing (NGS) technology. Epidemiological data including data from this study and reported articles from Zhejiang, China, were included. Further analyses based on AST, WGS, and epidemiological date include virulence genes, antibiotic resistance-related mutations, and phylogenetic trees based on 7 housekeeping genes and core-genome single nucleotide polymorphisms (SNPs).ResultsThe bacterial isolates in this study presented higher antibiotic resistance rates than previously reported, especially against levofloxacin and clarithromycin. The point mutation A2147G in 23 S rRNA is specific to clarithromycin resistance. Mutations at position/s 87 and/or 91 of the gyrA gene amino acid sequence are highly consistent with levofloxacin resistance highly. The point mutations C1707T in 23 S rRNA and E463K in the gyrB gene have not been previously documented in China. All the bacterial isolates belong to Asian branches in the structure population. The resistance rate to clarithromycin of isolates from hosts born after January 1, 1977 is statistically higher than that of hosts born before 1977.ConclusionEradication therapy based on AST results is urgently needed in Zhejiang. The point mutation A2147G in 23 S rRNA and point mutations in the gyrA gene at amino acid/s 87 and/or 91 are sufficient for predicting resistance to clarithromycin and levofloxacin, respectively. The isolate with the mutation E463K in the gyrB gene represents a significant contribution to the field. Mutations in 23 S rRNA may offer valuable insights into the dynamics of H. pylori transmission among hosts.

Attitudes and Practices Regarding Helicobacter Pylori Infection Among the Public in Jordan: A Cross-Sectional Survey.

Helicobacter pylori is a major infection that can cause a variety of complications, including stomach cancer and peptic ulcers. There is a scarcity of research on the awareness of H. pylori in the general population in Jordan. Because public awareness and behavioral changes are powerful tools in curbing transmission rates, this study evaluated Jordanians' beliefs and behaviors about H. pylori infection. The study was carried out in 2021 between May and July. Those who met the requirements for inclusion were asked to fill out a questionnaire through interviews. The questionnaire had three sections: sociodemographic data, participants' attitudes regarding H. pylori infection, and daily practices that could affect H. pylori transmission. Responses were collected from 767 participants, 50.7% were females, 65.8% were married, and 65.1% had a high educational level. Only 31.6% of the participants held a positive attitude. The female gender was significantly associated with better attitudes regarding H. pylori infection. One-third of the interviewed participants showed good practices. The female gender and being 50 years old and above were significantly associated with better practices. This study demonstrated that attitudes and practices regarding H. pylori infection in Jordan were unsatisfactory. Subsequently, public health efforts should be aimed at modifying those behaviors to decrease the disease burden.

The Magnitude and associated factors of Helicobacter Pylori Infection among Dyspeptic Patients at the Arba Minch General Hospital in Southern Ethiopia

Background: Infection with Helicobacter pylori (H. pylori) is a major public health problem, with a higher prevalence reported in developing countries, including Ethiopia. Persistent H. pylori infection could result in chronic gastritis, duodenal ulcers, and subsequently gastric carcinoma. However, the burden of the infection varies within and between countries. Methods: An institution-based cross-sectional study was carried out on 422 adult dyspeptic patients attended at Arba Minch General Hospital from March 1st to June 30th, 2022. Pretested structured questionnaires were used to collect socio-demographic characteristics, clinical information, and other related factors for H. pylori infection. Stool samples were analyzed using the H. pylori fecal antigen rapid test kit. The data was analyzed using SPSS version 25. The p-value < 0.05 was considered statistically significant. Results: The overall magnitude of H. pylori was found to be 32.2% (136/422), with a 95% CI = (27.7-36.5). The highest proportion of H. pylori occurred in male study participants (55.1%) and in participants aged 31-40 years (42.6%). H. pylori stool antigen positivity was significantly associated with alcohol consumption [AOR = 1.87, 95% CI: (1.06-3.29)], smoking cigarettes [AOR = 2.75, 95% CI: (1.43-5.27)], and hand washing practice after the toilet [AOR = 3.02, 95% CI: (1.41-6.48)]. Conclusion: Overall, a considerable magnitude of H. pylori was identified in the setting. Alcohol consumption, smoking cigarettes, and hand washing practice after using the toilet were found to be statistically significantly associated with H. pylori infection. Health education is therefore essential, particularly regarding societal lifestyle changes and knowledge of the potential sources of infection and H. pylori transmission.

Frequency and seasonality of viable Helicobacter pylori in drinking water in Dhamar Governorate, Yemen.

Helicobacter pylori is an important and common bacterial pathogen in humans. The accumulated evidence of the existence of H. pylori in water from different environmental sources suggests a water-borne transmission route. This study aimed to investigate the occurrence of H. pylori in different water sources used by human populations in Dhamar Governorate, Yemen. 250 samples were randomly collected from the municipal water supply network, wells, and springs. The samples were processed, plated onto modified campy-blood agar, and incubated under microaerobic conditions for 4-10 days. Bacterial identification was based on morphological properties and biochemical tests. Bacteriological analysis showed that 9.6% and 13.2% of tap and surface water samples were contaminated with H. pylori, respectively. Despite a higher frequency in samples from rural areas, these were not significantly (p=0.068) more contaminated than the samples from urban areas. Regarding the seasonal variations of H. pylori detection, 85.71% of positive samples were detected in the late winter and spring seasons (February to May). To conclude, H. pylori transmission through water is likely to occur in Dhamar Governorate. Further prospective studies are highly recommended to provide further evidence and a clearer picture of H. pylori transmission.

Intracellular presence and genetic relationship of Helicobacter pylori within neonates' fecal yeasts and their mothers' vaginal yeasts.

Helicobacter pylori are transmissible from person to person and among family members. Mother-to-child transmission is the main intrafamilial route of H. pylori transmission. However, how it transmits from mother to child is still being determined. Vaginal yeast often transmits to neonates during delivery. Therefore, H. pylori hosted in yeast might follow the same transmission route. This study aimed to detect intracellular H. pylori in vaginal and fecal yeasts isolates and explore the role of yeast in H. pylori transmission. Yeast was isolated from the mothers' vaginal discharge and neonates' feces and identified by internal transcribed spacer (ITS) sequencing. H. pylori 16S rRNA and antigen were detected in yeast isolates by polymerase chain reaction and direct immunofluorescence assay. Genetic relationships of Candida strains isolated from seven mothers and their corresponding neonates were determined by random amplified polymorphic DNA (RAPD) fingerprinting and ITS alignment. The Candida isolates from four mother-neonate pairs had identical RAPD patterns and highly homologous ITS sequences. The current study showed H. pylori could be sheltered within yeast colonizing the vagina, and fecal yeast from neonates is genetically related to the vaginal yeast from their mothers. Thus, vaginal yeast presents a potential reservoir of H. pylori and plays a vital role in the transmission from mother to neonate.

Potentially Infectious Helicobacter pylori in Tap Water in Kermanshah, Western Iran.

Although the pathogenesis of Helicobacter pylori is well-defined, the origin and transmission of the bacterium have remained largely unknown. The water transmission hypothesis suggested that water acts as a carrier in oral-fecal transmission, especially in high-prevalence areas. We aimed to evaluate the possible contamination of tap water with infective H. pylori in Kermanshah, Iran from Sep-Oct 2020. Tap water samples were collected from varieties of probable high-alert regions and the viability of H. pylori were achieved using culture and real-time PCR techniques (ureA gene expression). Out of 50 tap water samples, 3 were positive for H. pylori before enrichment and 6 were positive after enrichment by RT qPCR, while H. pylori colonies of two samples were observed on brucella agar plates. The results of positive samples demonstrated the probable presence of viable H. pylori in tap water samples, showing that tap water distribution systems could be a potential route for H. pylori transmission.

Assessment of Helicobacter pylori infection

Background: A Gram-negative bacteria called Helicobacter pylori (H. pylori) colonizes the stomach lining and is a substantial contributor to several gastrointestinal illnesses. It is a spiral-shaped bacterium with several modifications that enable it to live in the stomach’s severely acidic environment. Methods: In this paper, we discussed Helicobacter pylori (H. pylori) disease, its epidemiology, pathophysiology, hygiene, causes, risk factors, clinical manifestation and complications, method of transmission, diagnosis, treatment, and incubation period in the human body. Results: The incidence and prevalence of H. pylori infection can be influenced by factors such as age, socioeconomic status, geographical location, and living conditions. Generally, H. pylori infection is more common in developing countries with poorer sanitation and hygiene standards. it is estimated that approximately 50% of the world’s population is infected with H. pylori. Conclusion: We have concluded that although the precise way of H. pylori transmission is not entirely understood, it is thought to largely spread via oral-oral or fecal-oral routes. It can manufacture the enzyme urease, which turns stomach urea into ammonia, neutralizing the acidic environment and creating a suitable environment for its life. Today, H. pylori is recognized as the primary contributor to chronic gastritis. Key Words: Helicobacter pylori (H. pylori), epidemiology, causes, complication, prevalence, treatment

Helicobacter pylori virulence factors: subversion of host immune system and development of various clinical outcomes.

Helicobacter pylori (H. pylori) is a worldwide spread bacterium, co-evolving with humans for at least 100 000 years. Despite the uncertainty about the mode of H. pylori transmission, the development of intra-gastric and extra-gastric diseases is attributed to this bacterium. The morphological transformation and production of heterogenic virulence factors enable H. pylori to overcome the harsh stomach environment. Using numerous potent disease-associated virulence factors makes H. pylori a prominent pathogenic bacterium. These bacterial determinants are adhesins (e.g., blood group antigen-binding adhesin (BabA)/sialic acid-binding adhesin (SabA)), enzymes (e.g., urease), toxins (e.g., vacuolating cytotoxin A (VacA)), and effector proteins (e.g., cytotoxin-associated gene A (CagA)) involved in colonisation, immune evasion, and disease induction. H. pylori not only cleverly evades the immune system but also robustly induces immune responses. This insidious bacterium employs various strategies to evade human innate and adaptive immune responses, leading to a life-long infection. Owing to the alteration of surface molecules, innate immune receptors couldn't recognise this bacterium; moreover, modulation of effector T cells subverts adaptive immune response. Most of the infected humans are asymptomatic and only a few of them present severe clinical outcomes. Therefore, the identification of virulence factors will pave the way for the prediction of infection severity and the development of an effective vaccine. H. pylori virulence factors are hereby comprehensively reviewed and the bacterium evasion from the immune response is properly discussed.

The Association Between Oral Helicobacter pylori and Gastric Complications: A Comprehensive Review.

Helicobacter pylori (H. pylori) is linked to chronic gastritis, duodenal or gastric ulcers, and gastric cancer (GC). Because the oral cavity is the first component of the gastrointestinal tract (GIT) and the entrance point for H. pylori, it has been proposed as a possible reservoir of H. pylori. As a result, a putative oral-oral transmission pathway of H. pylori poses the possibility of whether personal contact, such as kissing or sharing a meal, might trigger H. pylori transmission. As a result, several investigations have been done on this issue using various approaches for detecting H. pylori in oral and stomach samples. Furthermore, the relationship between H. pylori and gastrointestinal disorders has yet to be studied. The evidence for the association between H. pylori and gastric diseases and their complications is still a controversial subject due to the existing literature in this review. The goal of this comprehensive review was to collect all available published articles and critically evaluate existing investigations looking into the relationship between oral H. pylori contamination and the danger of gastric complications. Few studies indicated an association between H. pylori and gastric diseases. Furthermore, more longitudinal randomized clinical studies to further investigate the association between H. pylori and gastric diseases are warranted.

Concurrence of Helicobacter pylori Infection and Its Associated Factors in Korean Couples.

BackgroundThis study evaluated the prevalence of Helicobacter pylori infection and the risk factors associated with H. pylori transmission among spouses.MethodsWe assessed the spousal concurrence of H. pylori infection using the Campylobacter-like organism (CLO) test under gastro-endoscopy in 132 couples. Based on the CLO test results, participants were categorized into H. pylori concurrent and independent groups. The chi-square test and Student t-test were performed for demographic comparisons between the concurrent and independent H. pylori groups. In addition, multivariate logistic regression analysis was performed to identify factors associated with concurrent H. pylori infection.ResultsThe study revealed that the concurrence rate of H. pylori infection was 42.4% in married Korean couples. The odds ratio (OR) derived from the concurrence of H. pylori infection tended to decrease in older couples (OR, 0.975; 95% confidence interval [CI], 0.949–1.002; P=0.072). Gastric erosion was also associated with a decreased OR for concurrent infection (OR, 0.488; 95% CI, 0.295–0.808; P=0.005). Conversely, active duodenal ulcers were associated with an increased OR for concurrent infections (OR, 6.501; 95% CI, 1.267–33.346; P=0.025). Duodenal ulcer scars tended to increase the OR of concurrent infections (OR, 1.392; 95% CI, 0.815–2.380; P=0.226).ConclusionSpousal transmission and concurrence of H. pylori infection were negatively associated with gastric erosion; however, they were positively associated with active duodenal ulcers. Further studies are warranted to elucidate the mechanisms underlying these findings.

Investigation of Helicobacter pylori transmission between spouses

Investigation of Helicobacter pylori transmission between spouses

Milk and dairy products as a possible source of environmental transmission of Helicobacter pylori

Helicobacter pylori (H. pylori) is found worldwide, and it is estimated that more than 50% of the population is infected. The presence of H. pylori in the gastrointestinal tract is associated with the occurrence of serious human diseases such as chronic gastritis, duodenal ulcer or gastric cancer. Therefore, the International Agency for Research on Cancer classified H. pylori as a Group 1 carcinogen in 1994. The routes of H. pylori transmission are not yet precisely known. Many authors agree that humans may become infected by H. pylori through foodstuffs. Milk is one of the basic foods of people of all age categories. Helicobacter pylori has been isolated from milk derived from various livestock, such as cows, sheep, goat, camel or buffalo milk. This review research paper indicates that H. pylori may be present in different types of foods and suggests that consumption of milk and selected dairy products may be a source of H. pylori infection for humans.

Detection of Helicobacter pylori in oral yeasts from students of a Chilean university.

Nearly 73% of the Chilean population is infected with Helicobacter pylori (H. pylori), a factor predisposing for gastric cancer. Recent studies have demonstrated the presence of this pathogen within yeasts, suggesting that this fact can directly influence the failure of a treatment, transmission, and reinfection. To detect the presence of H. pylori inside oral yeasts isolated from students of the University of Concepción (Chile). 72 samples, obtained from the oral cavity using cotton swabs were incubated in YPD broth for 48h at 37°C and posteriorly seeded in Sabouraud Dextrose agar plus chloramphenicol at the same temperature and for the same time. Yeasts isolated were observed microscopically (wet mounting and Gram-stained) and identified using microbiological techniques. Intracellular H. pylori detection was performed by the amplification of 16S rDNA by PCR. Oral yeasts were detected in 24 samples (33.3%), being C. albicans (79.2%) the most frequent species, followed by C. dubliniensis (12.4%), C. krusei (4.2%), and C. tropicalis (4.2%). When analyzed by PCR, 15 of the 24 oral yeasts 62.5 % were positive for H. pylori 16S rDNA. From the 15 individuals positive for yeast harboring H. pylori, 81% of them reported stomach discomfort, and the presence of the bacteria was diagnosed at some moment in 20% of them. The intracellular presence of the H. pylori in oral yeasts suggests an endosymbiotic relationship of these microorganisms, which could favor H. pylori transmission and reinfection in the gastrointestinal tract.

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.

Infections with Helicobacter pylori and challenges encountered in Africa.

Helicobacter pylori (H. pylori) is the causative agent of gastritis, peptic ulcer disease, mucosa associated lymphoid tissue lymphoma and gastric cancer (GC). While this bacterium infects 50% of the world’s population, in Africa its prevalence reach as high as 80% as the infection is acquired during childhood. Risk factors for H. pylori acquisition have been reported to be mainly due to overcrowding, to have infected siblings or parent and to unsafe water sources. Despite this high H. pylori prevalence there still does not exist an African guideline, equivalent to the Maastricht V/Florence Consensus Report of the European Helicobacter and Microbiota Study Group for the management of this infection. In this continent, although there is a paucity of epidemiologic data, a contrast between the high prevalence of H. pylori infection and the low incidence of GC has been reported. This phenomenon is the so-called “African Enigma” and it has been hypothesized that it could be explained by environmental, dietary and genetic factors. A heterogeneity of data both on diagnosis and on therapy have been published. In this context, it is evident that in several African countries the increasing rate of bacterial resistance, mainly to metronidazole and clarithromycin, requires continental guidelines to recommend the appropriate management of H. pylori. The aim of this manuscript is to review current literature on H. pylori infection in Africa, in terms of prevalence, risk factors, impact on human health, treatment and challenges encountered so as to proffer possible solutions to reduce H. pylori transmission in this continent.

Presence of Helicobacter Pylori in the Stomach and Laryngeal Mucosal Linings in Patients with Laryngeal Cancer.

SUMMARY – Helicobacter (H.) pylori is the cause of one of the most common chronic bacterial infections in humans. Risk factors for the development of laryngeal cancer are cigarette smoke, alcohol, and human papillomavirus. Several papers report on H. pylori isolated in tooth plaque, saliva, middle ear and sinuses. Many articles describe the presence of H. pylori in laryngeal cancer cases, however, without noting the possible source of infection, i.e. stomach or oral cavity. The aim of this study was to determine which patients and to what extent simultaneously developed H. pylori colonization in the stomach and the larynx. Prospective examinations were performed in 51 patients with laryngeal squamous cell carcinoma. The study group included patients with laryngeal squamous cell carcinoma histopathologically confirmed by two independent pathologists. The patients underwent fiber esophagogastroduodenoscopy with tumor tissue biopsy. Laryngeal and gastric biopsies were examined by histologic staining technique for histopathologic detection of H. pylori and with DNA analyses using the standardized fluorescent ABI Helicobacter plus-minus PCR assay. Laryngeal carcinoma patients showed positive H. pylori test results simultaneously in the laryngeal and stomach areas, implying H. pylori transmission from the stomach to the laryngeal area. In addition, H. pylori positive test results along with negative H. pylori results in the stomach region were also recorded, suggesting a possible bacteria migration from the oral cavity. In conclusion, H. pylori was found in the area of laryngeal carcinoma, and its migration appeared likely to occur both upwards (from the stomach to the mouth) and downwards (from the oral cavity to the stomach).

Are non-pylori helicobacters present in the human oral cavity?

Helicobacter pylori (H. pylori) is a human gastric pathogen. Because of presence of H. pylori oral cavity, there is a possibility of H. pylori transmission by oral-oral route. In a crosssectional study, the presence of some virulence factors of H. pylori and also non-pylori Helicobacters in dental plaque samples of participants was investigated. The samples were collected from at least two teeth surfaces. DNA of the samples was extracted using specific kit. The presence of dupA (jhp0917 and jhp0918) and babA2 genes and also Helicobacter genus and H. pylori species was investigated using polymerase chain reaction by specific primers. In total 44% (20/45) and 86.7% (39/45) of samples was positive for ureC and 16SrRNA genes respectively. The frequency of babA2, jhp0917 and jhp0918 genes in H. pylori isolates were 40, 20 and 65% respectively. It seems 19 samples were positive probably non-pylori Helicobacters. In the present study we report for the first time the presence of non-pylori Helicobacter species and also high frequency of babA2 and dupA genotypes in dental plaque samples.

Detection of Helicobacter pylori in Drinking Water by Loop-Mediated Isothermal Amplification

Background: There should be a public environmental reservoir for Helicobacter pylori in the developing countries, such as Iran, due to their high infection rate of over 70%. Epidemiological findings revealed that water could be a possible source of H. pylori transmission. However, high prevalence of H. pylori in drinking water in Kermanshah, West of Iran, was detected in the authors' previously published study. The current study aims at designing a more accurate and rapid procedure to investigate the prevalence of Helicobacter species and cagA gene in drinking water samples in Kermanshah, from October to December 2012. Methods: In the current study, 60 tap water samples were obtained and specific polymerase chain reaction (PCR) targeted cagA and 16s rRNA was performed. A loop-mediated isothermal amplification (LAMP) targeted ureC gene was developed to accurately detect H. pylori in water samples. Results: The prevalence of ureC by PCR, ureC by LAMP and 16s rRNA by PCR were 26.67%, 38%, and 61.67%, respectively. Among 24 samples (40%), 1 of the 2 tests was positive. The prevalence of cagA gene among ureC positive, 16s rRNA positive and all samples were 18.75%, 13.51%, and 10%, respectively. Conclusions: Helicobacter pylori contamination in drinking water was considerably higher using LAMP compared with PCR. It is noteworthy that some H. pylori positive samples were also positive for Caga.

Role of food in environmental transmission of Helicobacter pylori.

Helicobacter pylori (H.pylori) is a gram-negative bacterium that has infected more than half of the world's population. This pathogen colonizes the human gastric mucosa and is usually acquired during childhood. It is an important cause of peptic ulcers, chronic gastritis and stomach cancer. Among the risk factors for acquisition of H. pylori infection, poor socioeconomic status, poor sanitization and hygiene practices, and contaminated food and water, are the most significant ones. The main route of H. pylori transmission is still unknown. Studies show that H.pylori bacteria can spread directly from one person to the other, or indirectly from an infected person to the environment. Person to person transmission is divided into fecal-oral, gastric-oral, oral-oral, sexual routes. Presently, interpersonal pathways are more acceptable than environmental exposure routes. Literatures indicate the presence and survival of H. pylori in food samples, such as milk, vegetables and meat, and suggest these foods may play an important role in the environmental transmission of this pathogen. In addition, other studies report the presence of H. pylori in the gastric tissue of some animals (e.g. sheep and cow) and therefore, it is likely they participate in the food chain transmission as reservoirs besides human. Although there are findings which indicate the probable role of food products in the environmental transmission of H. pylori, there is still not enough direct evidence to confirm this and more studies are needed. However, attention to food contamination sources (unhygienic water) and controlling them may prevent transmission of pathogens associated with health.

Isolation and characterization of Helicobacter pylori recovered from gastric biopsies under anaerobic conditions

Background and AimHelicobacter pylori can survive long incubation periods under anaerobic conditions, and should be possible to isolate under anaerobic conditions. Our aim was to isolate H. pylori in anaerobic conditions, from gastric biopsies of H. pylori infected patients. MethodsWe enrolled 27 patients with bleeding (erosive) gastritis (mean age 36.3 years, 55.6% male) from Hanoi, Vietnam. H. pylori status was confirmed by qPCR. ResultsH. pylori were recovered under anaerobic and micro-aerobic conditions from gastric biopsies in 16 patients. Anaerobic conditions yielded significantly higher H. pylori recovery rates than micro-aerobic conditions (81.3% vs. 31.3%, P= 0.01). H. pylori isolates were characterized by PCR for specific virulence markers and the genotypes were similar to those previously described in this region of the world. ConclusionsH. pylori can be isolated under anaerobic conditions. These findings may provide new insight into the physiology of this human pathogen and help to identify the route of H. pylori transmission.