Bacteria

Helicobacter pylori (commonly shortened to H. pylori) is a spiral-shaped bacterium that has evolved a unique ability: it survives in one of the harshest environments of the human body — the stomach. For decades, scientists believed that stomach ulcers and gastritis were caused solely by stress or diet. The discovery of H. pylori completely changed this perspective, proving that a bacterial infection could directly damage the stomach lining and even increase the risk of gastric cancer.

Klebsiella pneumoniae is a bacterium that lives quietly in the human body and the environment but has the potential to cause severe and often life-threatening infections. Belonging to the family Enterobacteriaceae, this microorganism is commonly found in the gut, skin, and respiratory tract. In healthy individuals, it rarely causes illness. However, when the immune system is weakened, or when the bacterium enters areas of the body where it should not be, it can trigger serious conditions such as pneumonia, bloodstream infections, urinary tract infections, and sepsis.

Bacteria are among the oldest living organisms on Earth. Invisible to the naked eye, they exist in virtually every environment: soil, water, air, and inside the human body. While many...