It’s been bugging humans for 58,000 years and we still can’t seem to shake it. H. pylori, a type of bacteria that thrives in the human stomach, is the most common chronic infection worldwide. While many people suffer no ill effects from it, in others it can cause ulcers or even gastric cancers.
So how do you get infected with h. pylori and when do you need to worry? That’s what @thebellydepot wanted to know on Twitter:
H. pylori can infect anyone, no matter their age, race, gender or where they live. Today, h. pylori is much more common in developing countries, where most people catch it as children. By age 50, more than 80% of people in developing countries will have been infected with the bacteria. In contrast, testing has shown that while children in developed countries like the U.S. are unlikely to have h. pylori, about 50% of people over 60 have it. For reasons that are not entirely clear, African-American and Latino populations have higher rates of infection.
Oddly enough for a bug that’s been around for thousands of years, we actually aren’t completely sure how h. pylori is spread. The evidence we do have suggests that it’s spread from oral contact with others’ saliva or fecal material. Rates of h. pylori are higher in countries where water and food supplies are more likely to be contaminated with fecal material. H. pylori also seems to be more likely to spread within a family, so if one person gets it, their relatives might pick it up too.
Once someone is infected with h. pylori, it travels to the stomach and sets up shop underneath the mucous lining that protects the stomach lining. By damaging this mucous layer, it triggers inflammation and makes the stomach and part of the small intestine vulnerable to damage from the harsh acids produced during digestion.
The irritation caused by h. pylori can lead to ulcers or chronic gastritis that may cause abdominal pain, fatigue, bleeding or anemia. H. pylori is the cause of the vast majority of gastric and duodenal ulcers. In addition, over decades, the bacteria may lay the groundwork for stomach cancer and a type of gastric lymphoma. Studies suggest that infection raises the risk of stomach cancer 2-8 times the usual risk, and approximately 36% of gastric cancer in developed countries can be attributed to h. pylori.
However, the risk of developing cancer remains very low (about 1-3% according to some studies) even for people with the bug, and it appears to decrease after treatment. In fact, some gastric lymphomas may be cured simply by taking antibiotics to wipe out h. pylori. And here’s a bit of surprising good news: For unknown reasons, h. pylori infection appears to lower the risk of esophageal cancer.
Fortunately, we have developed good ways to test for and treat h. pylori. Because most people who have h. pylori suffer no negative effects, usually only people with symptoms consistent with ulcers or gastric cancer like pain, nausea, fatigue and fullness are tested and treated for the bacteria. Different kinds of tests for the bug include a noninvasive breath test, blood tests, stool tests, or biopsies of the stomach or small intestine.
Treatment consists of a combination of different antibiotics, and a medication to decrease acid production in the stomach. Often, doctors retest patients after they’ve finished their antibiotics to make sure the bacteria are gone. But once the pesky infection has been eliminated, reinfection is unlikely.