Thai medical scientists have developed the world's first dengue fever vaccine, which it plans to test over the next three years.

The vaccine will be tested in three phases, including on human subjects over the next three years.

Thailand's Department of Disease Control has made preparations for the tests in the country's central province of Ratchaburi.

About 2,500 people will be needed for the trial period during 2008-2010.

If the vaccine is a success, Thailand expects to save more than one billion-baht or 30 billion won a year in government expenses for the treatment of dengue sufferers.