Experimental vaccine against dengue 100% effective: study

PanARMENIAN.Net - An experimental vaccine against dengue, the world's most common mosquito-borne virus, was 100 percent effective in early trials and could speed up the pace of a vaccine against Zika, researchers said Wednesday, March 16, according to AFP.

Dengue -- which is in the same family of flaviviruses as Zika -- infects some 390 million people each year in more than 120 countries of the world.

The vaccine candidate, known as TV003, was tested in a group of 48 people -- half of whom received the vaccine, with the other half given a placebo.

TV003 is made by researchers at the U.S. National Institutes of Health (NIH) from a mixture of four weakened but live viruses, targeted to each of the four serotypes of dengue.

Six months after vaccination, the two groups were exposed to a weakened form of dengue serotype 2 virus, the hardest of the four dengue strains to prevent.

Of the 41 people that remained in the study until the end, none of the 21 who were vaccinated showed any evidence of dengue.

The 20 in the placebo group all had dengue virus in their blood. Eighty percent of them developed a rash, and 20 percent showed lower white blood cell counts, suggesting their bodies were fighting an infection.

The study was done in the United States, where dengue does not circulate in the population.

This helped researchers identify the vaccine's effectiveness in people who had not been previously exposed to any strain of dengue.

Researchers said their findings may assist in the development of a vaccine against Zika, which has been linked to surge in birth defects in Brazil.

Top U.S. health experts have said a vaccine against the mosquito-borne disease will take years to develop.

"We think that this is a tool that can really accelerate vaccine development, it's a tool that we think can be extrapolated to others flaviviruses," said Durbin, according to AFP.

"We hope to do this with Zika virus. There's an urgent need for a Zika vaccine."