Salmonella is a common intestinal bacterium that causes illness in humans. It is found worldwide in animals and can be transmitted to humans through contaminated foods like eggs, poultry and peanuts. After being consumed, Salmonella passes through the stomach and intestines, where it penetrates the intestinal wall and enters the bloodstream, potentially infecting the liver or spleen. Proper handwashing and food preparation can help prevent Salmonella transmission.