Scientists have made a promising advance for controlling dengue fever, a tropical disease spread by mosquito bites. They've rapidly replaced mosquitoes in the wild with skeeters that don't spread the dengue virus. (AP)

Last Wednesday at the International Biotechnology Congress in Havana, Cuba, leaders of a clinical trial announced their project for a vaccine against dengue fever.

The research director at the Genetic Engineering and Biotechnology Center, or Cigb, Gerardo Guill�n, said research in monkeys proved the vaccine's effectiveness in controlling the multiplication of the virus. The vaccine is designed to act on all four known variants of the dengue virus, Guill�n said.

Bugs that Give You More than a Sting

Guill�n said that so far there are no products in existence anywhere that prevent dengue fever, although several international pharmaceutical firms are developing weaker vaccines that use the virus itself to treat the illness.

Cigb worked with France's Pasteur Institute to develop the vaccine.

Dengue, which is transmitted by the Aedes aegypti mosquito, is characterized by a high fever and intense general malaise accompanied by skin eruptions.

Paraguay Threatened by Dengue

Last year, dengue epidemics broke out in several countries in Latin America.

According to figures from the Pan American Health Organization, each year the disease affects about 100 million people worldwide.

Laura Poll�n, leader of the Cuban opposition group known as the "Ladies in White," died from dengue in October of cardiorespiratory arrest at the age of 63. She had been hospitalized for over a week when the Calixto García Hospital in Havana confirmed that she had been diagnosed with Type 4 of the deadly disease.

In 2010, 1.5 million people were infected and over 1,000 died from dengue in Latin America alone.