A pill that vaccinates people against salmonella has been developed amid fears terrorists could turn the deadly food poisoning bug into a weapon.
Designed to be taken by mouth, it also has the added advantage of using the same pathway that salmonella uses to wreak havoc on the digestive system.
Salmonella is responsible for one of the most common food-borne illnesses in the world. In the US alone, the Centres for Disease Control and Prevention estimates there are about 1.4 million cases with 15,000 hospitalisations and 400 deaths each year.
It is thought that for every reported case, there are approximately 39 undiagnosed infections. Overall, the number of salmonella cases in the US has not changed since 1996.
There is no vaccine currently available for salmonella poisoning. Antibiotics are the first choice in treating infection, but the fact that some strains are quickly developing antibiotic resistance is a serious concern.
Professor Ashok Chopra, of The University of Texas Medical Branch, said: “In the current study, we analysed the immune responses of mice that received the vaccination by mouth as well as how they responded to a lethal dose of salmonella.
“We found that the orally administered vaccines produced strong immunity against salmonella, showing their potential for future use in people.”
Another dangerous aspect of salmonella is that it can be used as a bioweapon, which happened in Oregon in 1984 when a religious cult intentionally contaminated ten restaurant salad bars and sickened 1,000 people.