WASHINGTON (Reuters) - A new type of vaccine that sneaks into the body and then self-destructs -- all without needles -- may offer a new way to protect against a range of diseases, U.S. researchers reported on Monday. The researchers genetically engineered a type of Salmonella bacteria to carry a little piece of Streptococcus and dripped it into the mouths of mice. Reporting in the Proceedings of the National Academy of Sciences, they said the vaccine protected the mice, and the Salmonella carrier blew itself up.
