Rate of Helicobacter pylori Infection in Children and Clonality of Taiwan Strains

Abstract

The spiral shaped bacterium, Helicobacter pylori, is now regarded as the major cause of stomach diseases such as acute gastritis, gastric and duodenal ulcers, gastric lymphoma, and gastric adenocarcinoma (1,18). Many surveys have revealed that the number of the infected is low in the younger age and increases as a function of age, reaching a plateau at old age. The surveys also showed that the infection might be related to the state of hygiene: the poorer the hygiene, the higher the infection rate (6,9,11,20). Such notion is supported by the observation that the infection rate is higher in younger children whose hygienic concept and state are poorer than older children (6). It is now suggested that the infection occurs mostly during the younger age and that there are cohort effects (15,(23)(24)(25). These surveys were carried out using seroconversion as the marker for infection (6,8,10,13,14). Seroconversion only suggests that a child has encountered a sufficient dose of H. pylori to induce seroconversion, but does not necessarily have a current infection. Presumably, when the dose is below the threshold for the immune reaction, seroconversion might not be induced. Babies are presumably born without indigenous H. pylori. We therefore used three methods, culture for viable H. pylori, CLO test for the presence of urease, and PCR for the presence of dead or live H. pylori. We examined the H. pylori infection in babies and children to see how early a child might be infected and what the kinetics of infection would be as a function of age. Rate of Helicobacter pylori

Prevalence and risk factors of Helicobacter pylori infection in healthy schoolchildren

“…We think that this is may be an artifact of studying only 6‐ and 9‐year‐olds rather than a wider age range. Several epidemiological reports have shown that the rate of H. pylori infection increases significantly with age, with more than 80% of children being infected by the age of 10 years 10–15 . Although the chronic diseases linked to H. pylori are predominantly of adult onset, this bacterium often infects young children, but infection often remains asymptomatic and so it is difficult to obtain precise estimates of the age of acquisition 16,17 .…”

Extraction and Purification of Anti-Helicobacter pylori IgY

“…As major pathogen to cause gastric and duodenal ulcer and possibly gastric cancer, H. pylori can infect repeatedly more than 90% of adults (Chu et al, 2003). In this study, we established a procedure to produce the anti-H. pylori IgY through the eggs of White Leghorn hens.…”

“…Helicobacter pylori infection is frequently observed in adults worldwide and causes gastric and duodenal ulcers, gastric lymphoma, and possibly gastric carcinomas (Shin et al, 2002;Chu et al, 2003). Neutralization of highly acidic environment by secreted urease leads to Helicobacter spp.…”

Solid Lipid Nanoparticle Carrier Platform Containing Synthetic TLR4 Agonist Mediates Non-Viral DNA Vaccine Delivery

“…A mammalian expression vector pcDNA3.1(-) encoding 717 bp H. pylori antigen Urease alpha (GenBank: AF373569.1) [19] was synthesised by Genscript (Piscataway, NJ, USA). The 5782 bp construct was amplified in Escherichia coli strain DH5α and purified using the QIAprep Spin Miniprep Kit (Qiagen, Germantown, MD, USA) and stored at −20 • C until use.…”