A Japanese study published in The Pediatric Infectious Disease Journal, investigated the transmission of H. pylori within young patients and their families. Helicobacter pylori is a bacterium that weakens the protective mucous coating of the esophagus, stomach or duodenum, allowing acid to irritate the sensitive lining beneath, causing inflammation (gastritis) or ulcers to form. Most ulcers result from infection with H. pylori.

Forty-two pediatric patients, who were diagnosed with H. pylori gastritis with or without duodenal/stomach ulcers, took part in the study as well as 119 family members,  including mothers, fathers, siblings, and grandparents. Comparative results from the DNA fingerprinting analysis of the cultures taken, showed that mother-to-child transmission of the H. pylori infection is a major route of intra-familial clustering of the bacteria. Of the 42 mothers who were tested, 85.7% tested positive for H. pylori and 69% had the identical DNA strain to the one that their child had. Only 17% of the 39 fathers tested, had the identical bacteria strain, even though 73% tested positive for the bacteria. In one of the subjects, a grandmother’s H. pylori strain was identical to the grandchild’s and, in this case, she was the primary caregiver. Previous studies had shown that the H. pylori infection may be spread from sibling-to-sibling in large families. However, this study took place in Japan, where smaller families are the norm, and results indicated that 53% of siblings were H. pylori negative and sibling-to-sibling transmission was excluded in more than two-thirds of the families.

Researchers concluded that the predominance of mother-to-child transmission of H. pylori infection may be due to the amount of time a mother spends in contact with the child compared to time the father spends with the child. The researches noted that, for reasons not fully understood, the peak occurrences of infection appear during the first and fifth years of life.

First published in the Inside Tract® newsletter issue 173 – 2009
Konno M et al. Predominance of Mother-to-Child Transmission of Helicobacter pylori Infection Detected by Random Amplified Polymorphic DNA Fingerprinting Analysis in Japanese Families. The Pediatric Infectious Disease Journal. 2008;27(11):999-1003.