In the midst of growing concerns about dangerous dengue fever and other mosquito-borne illnesses, researchers have just completed phase three clinical testing of a dengue vaccine. Initial results are promising, giving professionals hope for the future.

According to the US Centers for Disease Control and Prevention, as many as 400 million people are infected with the dengue virus each year. Unlike the debilitating but non-fatal chikungunya virus that is sweeping across the Caribbean, dengue fever has been known to cause rare fatalities among the weak  and the untreated.

This year, the number of dengue outbreak appear to be spreading, with mosquito carriers moving further north as the weather warms.

To avoid unnecessary deaths, researchers have been clamoring to develop a vaccine that can stave off the infection, however, few have proven effective.

Now, a study detailing clinical trial results of a new dengue vaccine offer a ray of hope.

The study, published in The Lancet shows that among 6851 children from at-risk regions randomly selected to receive a vaccine regimen, only 117 children were confirmed to have contracted dengue fever more than 28 after final injection.

In comparison, 133 of 3424 initially healthy children given a placebo were infected.

This reportedly shows that the vaccine is about 56 percent effective.

Commenting on the study, Lancet member Annelies Wilder-Smith from Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore said that while encouraging, these results should not cause the scientific community to rest easy.

"For the moment, [this latest] vaccine is the best we have; however, with 56% efficacy it will never be a single solution," she said. "Continued support for the development of other novel strategies including drugs, improved case management, insecticides, and new approaches to vector control, is needed before effective dengue control becomes a credible prospect."

The study was published in The Lancet on July 11.