Scientists working independently in the San Diego-based Sidney Kimmel Cancer Center and the Sanger Center in Cambridge, England, have discovered that the genetic makeup of salmonella and typhoid are 99% identical - prompting suggestions that the food poisoning bacteria may hold the key to the development of a vaccine to eradicate the deadly disease.

Detailed in studies published today in the journal Nature, the research explained how the disease, which kills around 600,000 people a year and sickens 17m, is closely related to the germ, which causes a few days of stomach upset and diarrhoea in at least 1,000 times more people every year.

The only significant genetic difference between the two germs is that typhoid contains about 150 more strings of junk genetic material. Scientists believe that it is these junk genes that enable the typhoid germ to leave the human gut and enter the liver, the spleen and bone marrow, causing pneumonia and intestinal bleeding.

From the Kimmel Cancer Center, molecular biologist Michael McClelland revealed that the discovery could help researchers to modify salmonella bacteria and create a vaccine effective enough to eradicate typhoid across the globe.