Helicobacter pylori serostatus in backpackers following travel to tropical countries.

Abstract

The mode of transmission of Helicobacter pylori is unknown. The seroprevalence of H. pylori and the rate of transmission of feco-oral pathogens in developing countries are both high. Long-term travelers to these regions, who come from developed countries are thus potentially at increased risk of an infection with this bacterium. We studied the H. pylori serology status before and after travel of 104 backpackers who traveled to tropical countries; 76 medical students who did not leave Israel served as controls. Southeast Asia (70%) and South America (24%) were the major destinations, but the area of travel had no effect on the seroconversion rate. The total time spent abroad was 53 person-years. Thirty six of the travelers and 30 controls were positive at the outset. Seropositivity at entry was significantly associated with being a Sepharadic Jew or having a parent with a peptic ulcer disease. The majority of travelers (86.5%) and controls (92.1%) did not change their serostatus. Four travelers seroconverted, but 10 seroreverted, while three controls seroconverted, and three others seroreverted. No significant association with gastroenteritis was found. Serostatus may have been affected by mefloquine use because none of the four seroconverters, but eight of 10 seroreverters used it as malaria prophylaxis. In vitro studies demonstrated that mefloquine has anti-H. pylori activity. Feco-oral transmission is apparently not an important route of transmission of this organism among travelers.

Anti-Helicobacter pylori Potential of Artemisinin and Its Derivatives

“…It may not be out of place to mention here that a recent epidemiological study in child refugees in Western Australia indicated that premigration antimalarial treatment significantly reduced the odds of H. pylori infection after adjusting for age and sex and therefore predicted a protective effect of antimalarials against H. pylori infection (6). An earlier in vitro study with backpackers from developed countries after travel to tropical countries indicated that mefloquine, a traveler's choice antimalarial, has anti-H. pylori activity (39). Whereas the latter study corroborates the findings described above, the former study indirectly supports our serendipitous observation that artemisinin has strong anti-H. pylori effect.…”

A conceptual model of water's role as a reservoir in Helicobacter pylori transmission: a review of the evidence

“…However, low rates of co-infection do not eliminate the possibility of a common-source transmission as HAV is more contagious than H. pylori, HAV infection lasts a relatively short period of time, multiple routes of transmission may exist for each organism and the distribution of the two microorganisms in the population may be different [81]. Non-significant differences in H. pylori prevalence of workers occupationally exposed and not exposed to sewage [82,83] and low rates of seroconversion among travellers to developing countries [84,85] have led some to reject the notion of common-source pathways. However, this ignores the likelihood that people take special precautions to avoid potentially high-risk exposures while at work or travelling.…”