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

At Khmer Rouge Court, Long-Awaited Verdict Approaches

First phase of trial, which is coming to an end, has focused on forced exodus of Phnom Penh in 1975 - and now many are hopeful justice will be served More

Video When Fighting Eases, Gazans Line Up at Bakeries

When there is a lull in the conflict, residents who have been hunkered down in their apartments rush out to stock up on food and other necessities More

Video Information War Rages Alongside Real One in Ukraine

Downing of Malaysian airliner, allegations of cross-border shelling move information war in war-torn country to a new level More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Information War Rages Alongside Real One in Ukrainei
X
Al Pessin
July 31, 2014 8:13 PM
The downing of the Malaysian airliner two weeks ago, and allegations that Russians are shelling Ukrainian troops across the border, have moved the information war swirling around the Ukrainian conflict to a new level. VOA's Al Pessin reports from Kyiv.
Video

Video Information War Rages Alongside Real One in Ukraine

The downing of the Malaysian airliner two weeks ago, and allegations that Russians are shelling Ukrainian troops across the border, have moved the information war swirling around the Ukrainian conflict to a new level. VOA's Al Pessin reports from Kyiv.
Video

Video When Fighting Eases, Gazans Line Up at Bakeries

When there is a lull in the conflict in Gaza, residents who have been hunkered down in their apartments rush out to stock up on food and other necessities. Probably the most important destination is the local bakery. VOA’s Scott Bobb reports from Gaza City.
Video

Video US-Funded Program Offers Honduran Children Alternative to Illegal Immigration

President Obama and Central American leaders recently agreed to come up with a plan to address poverty and crime in the region that is fueling the surge of young migrants trying to illegally enter the United States. VOA’s Brian Padden looks at one such program in Honduras - funded in part by the United States - which gives street kids not only food and safety but a chance for a better life without, crossing the border.
Video

Video 'Fab Lab' Igniting Revolution in Kenya

The University of Nairobi’s Science and Technology Park is banking on 3-D prototyping to spark a manufacturing revolution in the country. Lenny Ruvaga has more for from Nairobi's so-called “FabLab” for VOA.
Video

Video Gazans in Shelled School Sought Shelter

Israel's air and ground assault against Hamas-led fighters in Gaza has forced many Palestinians to flee their homes, seeking safety. But safe places are hard to find, as VOA’s Scott Bobb reports from Jabaliya.
Video

Video Rapid Spread of Ebola in West Africa Prompts Global Alert

Across West Africa, health officials are struggling to keep up with what the World Health Organization describes as the worst ebola outbreak on record. The virus has killed hundreds of people this year. U.S. President Barack Obama and other world leaders are watching the developments closely as they weigh what actions, if any, are needed to help contain the disease.
Video

Video Michelle Obama: Young Africans Need to Embrace Women's Rights

U.S. first lady Michelle Obama urged some of Africa's best and brightest to advocate for women's rights in their home countries. As VOA's Pam Dockins explains, Obama spoke to some 500 participants of the Young African Leaders Initiative, a six-week U.S.-based training and development program.
Video

Video Immigrant Influx on Texas Border Heats Up Political Debate

Immigrants from Central America continue to cross the U.S.-Mexico border in south Texas, seeking asylum in the United States, as officials grapple with ways to deal with the problem and provide shelter for thousands of minors among the illegal border crossers. As VOA's Greg Flakus reports from Houston, the issue is complicated by internal U.S. politics and U.S. relations with the troubled nations that immigrants are fleeing.
Video

Video Study: Latino Students Most Segregated in California

Even though legal school segregation ended in the United States 60 years ago, one study finds segregation still occurs in the U.S. based on income and race. The University of California Los Angeles Civil Rights Project finds that students in California are more segregated by race than ever before, especially Latinos. Elizabeth Lee reports for VOA from Los Angeles.

AppleAndroid