Salmonella spreads by targeting and changing cells that line the gut, researchers have discovered.
The changes in the gut lining allow bugs to thrive.
As a result, salmonella bacteria are able to cross the intestine wall and infect vital organs including the kidneys and liver.
The University of Edinburgh research found that the salmonella released a protein, SopB, that changed the makeup of the cells, causing a dramatic increase in cells called microfold.
The discovery sheds light on how bacterial infections occur and spread.
Salmonella food poisoning can lead to diarrhoea, fever and even death particularly in young children.