Present in more than half the world's population, Helicobacter pylori is a bacterium that is often inconspicuous but dangerous. Classified as a carcinogen by the WHO, it is believed to be responsible for millions of cases of stomach cancer each year. This article focuses on this invisible killer, which is also prevalent in Africa.

A seemingly ordinary bacterium

Discovered in the 1980s by Australian researchers Barry Marshall and Robin Warren, Helicobacter pylori (or H. pylori ) lives in the lining of the stomach, where it causes chronic inflammation.

For a long time, it was believed that ulcers were caused by stress or a poor diet. We now know that this bacterium is the main cause of gastritis and gastric ulcers , and that it can eventually lead to cancer .

Often, the infection goes unnoticed. But behind this silence, H. pylori slowly eats away at the stomach lining and damages the cells that protect it.

Gastric cancer: the 5th most common cancer in the world

According to the International Agency for Research on Cancer (IARC), gastric cancer is now the fifth most diagnosed cancer and the fifth leading cause of cancer death worldwide.

Each year, nearly 770,000 people die from it , and about one million new cases are recorded.

Research conducted by Nature Medicine in 2024 estimates that up to 76% of gastric cancers are attributable to Helicobacter pylori , representing between 8 and 12 million potential cases in the coming years if nothing is done.

An infection that is very common in Africa

In Africa, the bacteria is widespread. Studies suggest infection rates exceeding 70% in several countries.

Lack of access to clean water, overcrowding and certain domestic practices (sharing utensils, communal meals) promote its spread.

The problem is that screening remains rare and symptoms are often overlooked. As a result, many cases are detected at an advanced stage.

How the bacteria affects the stomach

H. pylori secretes enzymes that neutralize gastric acidity, allowing it to survive in a normally hostile environment.

But this adaptation mechanism causes chronic inflammation which, in the long term, damages tissues.

The cells in the stomach then undergo mutations that can develop into a malignant tumor.

Not all infections lead to cancer, but certain factors increase the risk:

-smoking,

-a diet high in salt or preservatives,

-a family history of gastric cancer,

-and the presence of more virulent strains (such as those carrying the CagA gene ).

Diagnosis and treatment

The diagnosis is based on various examinations:

-urea breath test ,

-blood or stool analysis ,

-endoscopy for severe cases.

The treatment combines two antibiotics and a proton pump inhibitor (PPI) for 10 to 14 days.

Once the treatment is complete, a follow-up test confirms the eradication of the bacteria.

Doctors emphasize the importance of not interrupting treatment to avoid bacterial resistance, which is becoming increasingly common.

Good habits to prevent infection

-Drink clean or boiled water

-Wash your hands before meals

-Wash the fruits and vegetables thoroughly

-Avoid sharing utensils or toothbrushes

-Consult a doctor if you experience persistent pain or heartburn.

Prevention, coupled with targeted screening, is the best weapon to curb the progression of gastric cancer in high prevalence regions.

An invisible but avoidable enemy

Often silent, Helicobacter pylori can live for years in the stomach without causing symptoms, while preparing the ground for serious illness.

Experts say this is a major public health issue , especially in developing countries.

"We know how to identify and treat H. pylori . The real challenge is to act before it causes irreversible damage," emphasizes a WHO report.

In short, this bacterium is not inevitable: it can be detected, treated, and eliminated. However, it is essential to talk about it and raise awareness.