News / Health

Dengue Fever Vaccine Trials Clear First Hurdle

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

Tired of Waiting, South Africans Demand Change ‘Now’

With chronic poverty and lack of basic services largely fueling recent xenophobic attacks, many in Rainbow Nation say it’s time for government to act More

Challenges Ahead for China's Development Plans in Pakistan

Planned $46 billion in energy and infrastructure investments in Pakistan are aimed at transforming the country into a regional hub for trade and investment More

'Forbidden City' Revisits Little Known Era of Asian-American Entertainment

Little-known chapter of entertainment history captured in 80s documentary is revisited in new digitally remastered format and book More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Cinema That Crosses Borders Showcased at Tribeca Film Festivali
X
April 24, 2015 4:09 AM
Among the nearly 100 feature length films being shown at this year’s Tribeca Film Festival in New York City are more than 20 documentaries and features with international appeal, from a film about a Congolese businessman in China, to documentaries shot in Pakistan and diaspora communities in the U.S., to a poetic look at disaffected South African youth. VOA’s Carolyn Weaver has more.
Video

Video Cinema That Crosses Borders Showcased at Tribeca Film Festival

Among the nearly 100 feature length films being shown at this year’s Tribeca Film Festival in New York City are more than 20 documentaries and features with international appeal, from a film about a Congolese businessman in China, to documentaries shot in Pakistan and diaspora communities in the U.S., to a poetic look at disaffected South African youth. VOA’s Carolyn Weaver has more.
Video

Video UN Confronts Threat of Young Radicals

The radicalization and recruitment of young people into Islamist extremist groups has become a growing challenge for governments worldwide. On Thursday, the U.N. Security Council heard from experts on the issue, which has become a potent threat to international peace and security. VOA’s Margaret Besheer reports.
Video

Video Growing Numbers of Turks Discover Armenian Ancestry

In a climate of improved tolerance, growing numbers of people in Turkey are discovering their grandmothers were Armenian. Hundreds of thousands of Armenians escaped the mass deportations and slaughter of the early 1900's by forced conversion to Islam. Or, Armenian children were taken in by Turkish families and assimilated. Now their stories are increasingly being heard. Dorian Jones reports from Istanbul that the revelations are viewed as an important step.
Video

Video Migrants Trek Through Western Balkans to Reach EU

Migrants from Africa and other places are finding different routes into the European Union in search of a better life. The Associated Press followed one clandestine group to document their trek through the western Balkans to Hungary. Zlatica Hoke reports that the migrants started using that route about four years ago. Since then, it has become the second-most popular path into Western Europe, after the option of sailing from North Africa to Italy.
Video

Video TIME Magazine Honors Activists, Pioneers Seen as Influential

TIME Magazine has released its list of celebrities, leaders and activists, whom it deems the world’s “most influential” in 2015. VOA's Ramon Taylor reports from New York.
Video

Video US Businesses See Cuba as New Frontier

The Obama administration's opening toward Cuba is giving U.S. companies hope they'll be able to do business in Cuba despite the continuation of the U.S. economic embargo against the communist nation. Some American companies have been able to export some products to Cuba, but the recent lifting of Cuba's terrorism designation could relax other restrictions. As VOA's Daniela Schrier reports, corporate heavy hitters are lining up to head across the Florida Straits - though experts urge caution.
Video

Video Kenya Launches Police Recruitment Drive After Terror Attacks

Kenya launched a major police recruitment drive this week as part of a large-scale effort to boost security following a recent spate of terror attacks. VOA’s Gabe Joselow reports that allegations of corruption in the process are raising old concerns about the integrity of Kenya’s security forces.
Video

Video Japan, China in Race for Asia High-Speed Rail Projects

A lucrative competition is underway in Asia for billions of dollars in high-speed rail projects. Cambodia, India, Indonesia, Malaysia Thailand and Vietnam are among the countries planning to move onto the fast track. They are negotiating with Japan and the upstart Chinese who are locked in a duel to revolutionize transportation across Asia. VOA Correspondent Steve Herman in Bangkok has details.
Video

Video Scientists: Mosquitoes Attracted By Our Genes

Some people always seem to get bitten by mosquitoes more than others. Now, scientists have proved that is really the case - and they say it’s all because of genes. It’s hoped the research might lead to new preventative treatments for diseases like malaria, as Henry Ridgwell reports from London.
Video

Video Bible Museum Coming to Washington DC

Washington is the center of American political power and also home to some of the nation’s most visited museums. A new one that will showcase the Bible has skeptics questioning the motives of its conservative Christian funders. VOA religion correspondent Jerome Socolovsky reports.
Video

Video Armenia and Politics of Word 'Genocide'

A century ago this April, hundreds of thousands of Armenians of the Turkish Ottoman empire were deported and massacred, and their culture erased from their traditional lands. While broadly accepted by the U.N. and at least 20 countries as “genocide”, the United States and Turkey have resisted using that word to describe the atrocities that stretched from 1915 to 1923. But Armenians have never forgotten.
Video

Video Afghan First Lady Pledges No Roll Back on Women's Rights

Afghan First Lady Rula Ghani, named one of Time's 100 Most Influential, says women should take part in talks with Taliban. VOA's Rokhsar Azamee has more from Kabul.
Video

Video Keeping Washington Airspace Safe Is Tall Order

Being the home of all three branches of the U.S. federal government makes Washington, D.C. the prime target for those who want to make their messages and ideas heard. Unfortunately, many of them choose to deliver them in unorthodox ways, including from the air, as a recent incident clearly showed involving a gyrocopter landing on the Capitol’s West Lawn. VOA's George Putic has more.
Video

Video New Brain Mapping Techniques Could Ease Chronic Pain

From Boulder, Colorado, Shelley Schlender reports that new methods for mapping pain in the brain are providing validation for chronic pain and might someday guide better treatment.
Video

Video Hope, Prayer Enter Fight Against S. Africa Xenophobia

South Africa has been swept by disturbing attacks on foreign nationals. Some blame the attacks on a legacy of colonialism, while others say the economy is to blame. Whatever the cause, ordinary South Africans - and South African residents from around the world - say they're praying for the siege of violence to end. Anita Powell reports from Johannesburg.

VOA Blogs