The search for an effective vaccine against dengue, underway since the 1940s, might as bear fruit in 2015, says an India Today report. So far, no vaccine has been developed against the mosquito-borne diesease though there were several potential ones in various stages of development, notes the report.

The vaccine being developed by Sanofi Pasteur is said to be the frontrunner in the race and could be licensed by 2015, according to Dengue Vaccine Initiative. The vaccine will complement, but not replace, prevention methods such as vector control, the report pointed out. The vaccine is currently being tested on 4,000 children in Thailand and the company expects positive results by September this year.
Called the 'yellow fever dengue chimeric vaccine', it is based on a yellow fever vaccine strain genomic backbone in which two genes have been substituted with dengue genes. The vaccine would need to be given in three installments over one year to counter the threat from the four different types of dengue virus, none of which confers immunity to the others. Earlier studies have shown a balanced immune response against all the four dengue types. Scientists are expecting an efficacy rate of about 75 to 80 percent, added the report.