News / Health

Dengue Fever Vaccine Trials Clear First Hurdle

TEXT SIZE - +
Jessica Berman
Human trials of an experimental dengue fever vaccine have just concluded, and the experimental compound looks promising in offering protection against the complex mosquito-borne illness that afflicts millions of people living in tropical and sub-tropical regions.

Dengue fever, spread by the bite of an infected Aedes mosquito, is caused by four different but related viruses, making the development of a vaccine difficult, according to Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.

“The problem with a dengue vaccine is that unlike other viruses where if you get infected with one or vaccinated with one you’re protected, period, after you recover.  Whereas with dengue since there are four types, a vaccine needs to protect you against all four, because if you are only protected against one or two, you are still susceptible to one or the other of the three or four viruses,” Fauci said.

The U.S. government-funded trial was small, involving 112 healthy men and women between the ages of 18 and 50.  The purpose was to see whether the experimental vaccine, made up of live but weakened viruses, was both safe and stimulated an antibody response against all four dengue types.

Researchers at Johns Hopkins School of Public Health in Baltimore, Maryland formulated four different versions of the combination vaccine, and tested a separate vaccine in each of four groups of 20 study participants.  All of the dengue vaccines produced an antibody response.  But one experimental compound, called TV003, induced an immune response against all four dengue viruses in 45 percent of participants.  And an immune response to three viruses was seen in about 90 percent of participants.

The combination vaccine was safe, producing only a faint rash in about 60 percent of the participants, according to Fauci.

“I’m cautiously optimistic that we will have a vaccine after a period of time.  But again, this is in [the very early] stages - only a Phase One trial,” Fauci said.

The experimental dengue vaccine will undergo more safety and effectiveness testing in Phase 2 and Phase 3 trials, with researchers looking to see how well it creates an immune response against all four dengue viruses in Brazil and Thailand, where the mosquito-borne illness is endemic.

Dengue fever, also known as break bone fever, infects an estimated 50 million to 00 million people in developing countries each year.  Experts say the vaccine should cost less than $1 dollar a dose to produce, making it accessible to developing countries most impacted by the disease.

You May Like

Multimedia Relatives of South Korean Ferry Victims Fire at Authorities

46 people are confirmed dead, but some 250 remain trapped inside sunken ferry More

War Legacy Haunts Vietnam, US Relations

$84 million project aims to clean up soil contaminated by Agent Orange More

Wikipedia Proves Useful for Tracking Flu

Technique gave better results than Center for Disease Control (CDC) and Google’s Flu Trends More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Ukraine, Russia, United in Faith, Divided in Politicsi
X
Michael Eckels
April 19, 2014
There is a strong historical religious connection between Russia and Ukraine. But what role is religion playing in the current conflict? In the run-up to Easter, Michael Eckels in Moscow reports for VOA.
Video

Video Ukraine, Russia, United in Faith, Divided in Politics

There is a strong historical religious connection between Russia and Ukraine. But what role is religion playing in the current conflict? In the run-up to Easter, Michael Eckels in Moscow reports for VOA.
Video

Video Face of American Farmer is Changing

The average American farmer is now 58 years old, and farmers 65 and older are the fastest growing segment of the population. It’s a troubling trend signaling big changes ahead for American agriculture as aging farmers retire. Reporter Mike Osborne says a new report from the U.S. Census Bureau is suggesting what some of those changes might look like... and why they might not be so troubling.
Video

Video Donetsk Governor: Ukraine Military Assault 'Delicate But Necessary'

Around a dozen state buildings in eastern Ukraine remain in the hands of pro-Russian protesters who are demanding a referendum on self-rule. The governor of the whole Donetsk region is among those forced out by the protesters. He spoke to VOA's Henry Ridgwell from his temporary new office in Donetsk city.
Video

Video Drones May Soon Send Data From High Seas

Drones are usually associated with unmanned flying vehicles, but autonomous watercraft are also becoming useful tools for jobs ranging from scientific exploration to law enforcement to searching for a missing airliner in the Indian Ocean. VOA’s George Putic reports on sea-faring drones.
Video

Video New Earth-Size Planet Found

Not too big, not too small. Not too hot, not too cold. A newly discovered planet looks just right for life as we know it, according to an international group of astronomers. VOA’s Steve Baragona has more.
Video

Video Copts in Diaspora Worry About Future in Egypt

Around 10 percent of Egypt’s population belong to the Coptic faith, making them the largest Christian minority in the Middle East. But they have become targets of violence since the revolution three years ago. With elections scheduled for May and the struggle between the Egyptian military and Islamists continuing, many Copts abroad are deeply worried about the future of their ancient church. VOA religion correspondent Jerome Socolovsky visited a Coptic church outside Washington DC.
Video

Video Critics Say Venezuelan Protests Test Limits of Military's Support

During the two months of deadly anti-government protests that have rocked the oil-rich nation of Venezuela, President Nicolas Maduro has accused the opposition of trying to initiate a coup. Though a small number of military officers have been arrested for allegedly plotting against the government, VOA’s Brian Padden reports the leadership of the armed forces continues to support the president, at least for now.
Video

Video More Millenials Unplug to Embrace Board Games

A big new trend in the U.S. toy industry has more consumers switching off their high-tech gadgets to play with classic toys, like board games. This is especially true among the so-called millenial generation - those born in the 1980's and 90's. Elizabeth Lee has more from an unusual café in Los Angeles, where the new trend is popular and business is booming.
Video

Video Google Buys Drone Company

In its latest purchase of high-tech companies, Google has acquired a manufacturer of solar-powered drones that can stay in the air almost indefinitely, relaying broadband Internet connection to remote areas. It is seen as yet another step in the U.S. based Web giant’s bid to bring Internet to the whole world. VOA’s George Putic reports.
AppleAndroid