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

    Vietnam Urges US to Lift Lethal Weapons Ban Amid S. China Sea Tensions

    US president’s upcoming visit to Vietnam underscores strength of relationship, and lifting embargo would reflect that trust, ambassador says

    Are US Schools Turning a Blind Eye to Radical Qatari Preachers?

    Parade of radical Islamist clerics using mosque at Qatar’s Education City draws mounting criticism for American universities that maintain satellite branches there

    Why Islamic State Is Down But Not Out

    Despite loss of territory, group’s ferocious attacks over past three months seen as testimony to its continued durability and resourcefulness

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    Displaced By War, Syrian Artist Finds Inspiration Abroadi
    X
    May 02, 2016 1:36 PM
    Saudi-born Syrian painter Mohammad Zaza is among the millions who fled their home for an uncertain future after Syria's civil war broke out. Since fleeing Syria, Zaza has lived in Lebanon, Egypt, Jordan and now Turkey where his latest exhibition, “Earth is Blue like an Orange,” opened in Istanbul. He spoke with VOA about how being displaced by the Syrian civil war has affected the country's artists.
    Video

    Video Displaced By War, Syrian Artist Finds Inspiration Abroad

    Saudi-born Syrian painter Mohammad Zaza is among the millions who fled their home for an uncertain future after Syria's civil war broke out. Since fleeing Syria, Zaza has lived in Lebanon, Egypt, Jordan and now Turkey where his latest exhibition, “Earth is Blue like an Orange,” opened in Istanbul. He spoke with VOA about how being displaced by the Syrian civil war has affected the country's artists.
    Video

    Video Ethiopia’s Drought Takes Toll on Children

    Ethiopia is dealing with its worst drought in decades, thanks to El Nino weather patterns. An estimated 10 million people urgently need food aid. Six million of them are children, whose development may be compromised without sufficient help, Marthe van der Wolf reports for VOA from the Metahara district.
    Video

    Video Little Havana - a Slice of Cuban Culture in Florida

    Hispanic culture permeates everything in Miami’s Little Havana area: elderly men playing dominoes as they discuss politics, cigar rollers deep at work, or Cuban exiles talking with presidential candidates at a Cuban coffee window. With the recent rapprochement between Cuba and United States, one can only expect stronger ties between South Florida and Cuba.
    Video

    Video California Republicans Weigh Presidential Choices Amid Protests

    Republican presidential candidates have been wooing local party leaders in California, a state that could be decisive in selecting the party's nominee for U.S. president. VOA's Mike O’Sullivan reports delegates to the California party convention have been evaluating choices, while front-runner Donald Trump drew hundreds of raucous protesters Friday.
    Video

    Video Kurdish Football Team Helps War-Torn City Cope

    With the conflict still raging across much of Turkey’s predominantly Kurdish southeast, between the rebel PKK and the Turkish state, many Kurds are trying to escape the turmoil by focusing on the success of their football team Amedspor in Diyarbakir. The club is increasingly becoming a symbol for Kurds, not only in Diyarbakir but beyond. Dorian Jones reports from southeast Turkey.
    Video

    Video ‘The Lights of Africa’ - Through the Eyes of 54 Artists

    An exhibition bringing together the work of 54 African artists, one from each country, is touring the continent after debuting at COP21 in Paris. Called "Lumières d'Afrique," the show centers on access to electricity and, more figuratively, ideas that enlighten. Emilie Iob reports from Abidjan, the exhibition's first stop.
    Video

    Video Pakistani School Helps Slum Kids

    Master Mohammad Ayub runs a makeshift school in a public park in Islamabad. Thousands of poor children have benefited from his services over the years, but, as VOA's Ayesha Tanzeem reports, roughly 25 million school-age youths don't get an education in Pakistan.
    Video

    Video Florida’s Weeki Wachee ‘Mermaids’ Make a Splash

    Since 1947, ‘mermaids’ have fascinated tourists at central Florida’s Weeki Wachee Springs State Park with their fluid movements and synchronized ballet. Performing underwater has its challenges, including cold temperatures and a steady current, as VOA’s Lin Yang and Joseph Mok report.
    Video

    Video Somali, African Union Forces Face Resurgent Al-Shabab

    The Islamic State terror group claimed its first attack in Somalia earlier this week, though the claim has not been verified by forces on the ground. Meanwhile, al-Shabab militants have stepped up their attacks as Somalia prepares for elections later this year. Henry Ridgwell reports there are growing frustrations among Somalia’s Western backers over the country’s slow progress in forming its own armed forces to establish security after 25 years of chaos.
    Video

    Video Documentary Tells Tale of Chernobyl Returnees

    Ukraine this week is marking the 30th anniversary of the world's worst nuclear accident, at the Chernobyl nuclear power plant. Soviet officials at first said little about the accident, but later evacuated a 2,600-square-kilometer "exclusion zone." Some people, though, came back. American directors Holly Morris and Anne Bogart created a documentary about this faithful and brave community. VOA's Tetiana Kharchenko reports from New York on "The Babushkas of Chernobyl." Carol Pearson narrates.
    Video

    Video Nigerians Feel Bite of Buhari Economic Policy

    Despite the global drop in the price of oil, Nigerian President Muhammadu Buhari has refused to allow the country's currency to devalue, leading to a shortage of foreign exchange. Chris Stein reports from Lagos businessmen and consumers are feeling the impact as the country deals with a severe fuel shortage.
    Video

    Video  Return to the Wild

    There’s a growing trend in the United States to let old or underused golf courses revert back to nature. But as Erika Celeste reports from one parcel in Grafton, Ohio, converting 39 hectares of land back to green space is a lot more complicated than just not mowing the fairway.

    Special Report

    Adrift The Invisible African Diaspora