Scientists have used a new technology to develop a vaccine for norovirus, a cause of diarrhea and vomiting: They have tobacco plants grow the vaccine, according to a news release from the American Chemical Society.

Norovirus, sometimes called the "cruise ship virus," can spread quickly through passenger liners, schools, offices and military bases.

The process uses an engineered plant virus, which then causes the vaccine to grow in the plant. The technology opens the door to more efficient, inexpensive ways to bring vaccines quickly to the public, said Charles Arntzen.

He thinks the system could someday be used to quickly build up a stockpile of vaccines for newly emerged diseases such as the H1N1 strain known as swine flu.

The norovirus also mutates constantly, making it hard to develop a vaccine through traditional means.

"With plant-based vaccines, we can generate the first gram quantities of the drug and do clinical tests within eight to 10 weeks ... We could easily scale that up for commercial use in a two- to four-month period," he said.

Plant-based vaccine production also could be cheaper, he said. Building greenhouses costs less than sterilized facilities.

After successful experiments in mice, his team is developing a nasal delivery system for the virus-like particles. Arntzen expects to start clinical trials in late 2009 or early 2010.