News / Health

Malaria Vaccine Offers Hope

This undated photo supplied by WGBH/Nova shows a mosquito at work.
This undated photo supplied by WGBH/Nova shows a mosquito at work.

Related Articles

Study: Pregnant Women Not Gaining Access to Malaria Prevention

Malaria infections, primarily in sub-Saharan Africa, responsible for deaths of some 200,000 newborns and 10,000 new mothers each year

Audio Warmer Temps Trigger More Disease

Scientists say climate change creating favorable environment for germs, pests
VOA News
An experimental malaria vaccine appears to offer protection against infection in healthy adults, according to U.S. researchers. The researchers also say early results indicate the vaccine is safe and “generated an immune response” in the group of volunteers tested.

The vaccine, known as PfSPZ, is composed of live but weakened sporozoites of the species Plasmodium falciparum, the most deadly of the malaria-causing parasites.

Malaria is transmitted to humans by the bite of an infected mosquito. After the bite occurs, infectious malaria parasites in the immature, sporozoite stage of their life cycle, first travel to the liver, where they multiply, and then spread through the bloodstream.

“In this trial, we showed in principle that sporozoites can be developed into a malaria vaccine that confers high levels of protection and is made using the good manufacturing practices that are required for vaccine licensure,” said Dr. Robert A. Seder, chief of the Cellular Immunology Section of the NIAID Vaccine Research Center and principal investigator of the trial.

One potential drawback to the vaccine is that it appeared most effective when administered intravenously because lower doses given under the skin did not yield similar results.

“Despite this challenge, these trial results are a promising first step in generating high-level protection against malaria, and they allow for future studies to optimize the dose, schedule and delivery route of the candidate vaccine,” said Seder.

Fifty-seven adults between 18 and 45 years old took part in Phase One of the trial. Forty received the vaccine and 17 did not. Some of those who received the vaccine were given increasing doses. After seven days of monitoring, “no severe adverse effects associated with the vaccine occurred, and no malaria infections related to vaccination were observed.”

Furthermore, those who received the most vaccine generated more antibodies against malaria, researchers said.

Three weeks after the last dosage, participants -- both those who received the vaccine and the control group -- were exposed to bites from five mosquitoes carrying the P. falciparum strain from which the PfSPZ Vaccine was derived.

The researchers found that the higher dosages of PfSPZ Vaccine were associated with protection against malaria infection. Only three of the 15 participants who received higher doses of the vaccine became infected, compared to 16 of 17 participants in the lower dose group who became infected. Among the 12 participants who received no vaccine, 11 participants became infected, researchers said.

Researchers say they plan several follow-up studies to test dosage schedules and whether larger doses delivered under the skin can offer the same immune response.

“The global burden of malaria is extraordinary and unacceptable,” said Dr. Anthony Fauci, the NIAID director. “Scientists and health care providers have made significant gains in characterizing, treating and preventing malaria; however, a vaccine has remained an elusive goal. We are encouraged by this important step forward.”

The vaccine was developed by scientists at Sanaria Inc. The clinical evaluation was conducted by researchers at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, and their collaborators at the Walter Reed Army Institute of Research and the Naval Medical Research Center.

The results of the study were published in the August 8 issue of Science.

You May Like

Lesotho Faces New Round of Violence, Political Crisis

Brutal killing of military officer has sent former leaders back into S. Africa where they're watching anxiously as regional officials head in to try to restore peace More

Video US Diplomat Expects Adoption of Bosnian Massacre Anniversary Resolution

Samantha Power says there's broad consensus about killings in Bosnia's war, but Russia calls resolution 'divisive,' backs UN countermeasure More

UN Report Exposes Widespread Boko Haram Atrocities

Damning report graphically details pattern of vicious, widespread atrocities committed by Islamist militants More

This forum has been closed.
Comment Sorting
Comments
     
by: Toogee from: South Lake Tahoe
August 11, 2013 9:31 PM
This pic shown is that of an Aedes aegypti, which vectors a few nasty pathogens like dengue fever, chikungunya and yellow fever, but isn't a primary vector of malaria, is it?

by: kooni from: missipi
August 11, 2013 6:50 PM
they weren't actually bitten by the mosquito you idiot, there blood was tested with the malaria to see if the white cells respond to it.

by: Cranksy from: USA
August 09, 2013 1:31 PM
"Three weeks after the last dosage, participants -- both those who received the vaccine and the control group -- were exposed to bites from five mosquitoes carrying the P. falciparum strain from which the PfSPZ Vaccine was derived." I read the linked material that stated "[t]his controlled human malaria infection procedure — a standard process in malaria vaccine trials...." Isn't this type of exposure considered unethical? Volunteers or not these people didn't simply remain or return to the places where they live their lives to be naturally exposed to P. falciparum "the most deadly form of the malaria-causing parasites."

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Olympics Construction Scars Sacred Korean Mountaini
X
July 02, 2015 4:10 AM
Environmentalists in South Korea are protesting a Winter Olympics construction project to build a ski slope through a 500-year-old protected forest. Brian Padden reports that although there is strong national support for hosting the 2018 Pyeongchang Winter Olympics, there are growing public concerns over the costs and possible ecological damage at the revered mountain.
Video

Video Olympics Construction Scars Sacred Korean Mountain

Environmentalists in South Korea are protesting a Winter Olympics construction project to build a ski slope through a 500-year-old protected forest. Brian Padden reports that although there is strong national support for hosting the 2018 Pyeongchang Winter Olympics, there are growing public concerns over the costs and possible ecological damage at the revered mountain.
Video

Video Xenophobia Victims in South Africa Flee Violence, Then Return

Many Malawians fled South Africa early this year after xenophobic attacks on African immigrants. But many quickly found life was no better at home and have returned to South Africa – often illegally and without jobs, and facing the tough task of having to start over. Lameck Masina and Anita Powell file from Johannesburg.
Video

Video Family of American Marine Calls for Release From Iranian Prison

As the crowd of journalists covering the Iran talks swells, so too do the opportunities for media coverage.  Hoping to catch the attention of high-level diplomats, the family of American-Iranian marine Amir Hekmati is in Vienna, pleading for his release from an Iranian prison after nearly 4 years.  VOA’s Heather Murdock reports from Vienna.
Video

Video UK Holds Terror Drill as MPs Mull Tunisia Response

After pledging a tough response to last Friday’s terror attack in Tunisia, which came just days before the 10th anniversary of the bomb attacks on London’s transport network, British security services are shifting their focus to overseas counter-terror operations. VOA's Henry Ridgwell has more.
Video

Video Obama on Cuba: This is What Change Looks Like

President Barack Obama says the United States will soon reopen its embassy in Cuba for the first time since 1961, ending a half-century of isolation. VOA White House correspondent Luis Ramirez reports.
Video

Video Hate Groups Spread Influence Via Internet

Hate groups of various kinds are using the Internet for propaganda and recruitment, and a Jewish human rights organization that monitors these groups, the Simon Wiesenthal Center, says their influence is growing. The messages are different, but the calls to hatred or violence are similar. VOA's Mike O’Sullivan reports.
Video

Video US Silica Sand Mining Surge Worries Illinois Residents, Businesses

Increased domestic U.S. oil and gas production, thanks to advances known as “fracking,” has created a boom for other industries supporting that extraction. Demand for silica sand, used in fracking, could triple over the next five years. In the Midwest state of Illinois, people living near the mines are worried about how increased silica sand mining will affect their businesses and their health. VOA’s Kane Farabaugh has more in this first of a series of reports.
Video

Video Blind Somali Journalist Defies Odds in Mogadishu

Despite improving security in the last few years, Somalia remains one of the most dangerous countries to be a journalist – even more so for someone who cannot see. Abdulaziz Billow has the story of journalist Abdifatah Hassan Kalgacal, who has been reporting from the Somali capital for the last decade despite being blind.
Video

Video Texas Defies Same-Sex Marriage Ruling

Texas state officials have criticized the US Supreme Court decision giving same-sex couples the right to marry nationwide. The attorney general of Texas says last week's decision did not overrule constitutional "rights of religious liberty," and therefore officials performing wedding services can refuse to perform them for same-sex couples if it is against their religious beliefs. Zlatica Hoke reports on the controversy.
Video

Video Rabbi Hits Road to Heal Jewish-Muslim Relations in France

France is on high alert after last week's terrorist attack near the city Lyon, just six months after deadly Paris shootings. The attack have added new tensions to relations between French Jews and Muslims. France’s Jewish and Muslim communities also share a common heritage, though, and as far as one French rabbi is concerned, they are destined to be friends. From the Paris suburb of La Courneuve, Lisa Bryant reports about Rabbi Michel Serfaty and his friendship bus.
Video

Video Saudi Leaks Expose ‘Checkbook Diplomacy’ In Battle With Iran

Saudi Arabia’s willingness to wield its oil money on the global diplomatic stage appears to have been laid bare, after the website WikiLeaks published tens of thousands of leaked cables from Riyadh’s Ministry of Foreign Affairs. VOA's Henry Ridgwell reports.
Video

Video In Kenya, Police Said to Shoot First, Ask Questions Later

An organization that documents torture and extrajudicial killings says Kenyan police were responsible for 1,252 shooting deaths in five cities, including Nairobi, between 2009 and 2014, representing 67 percent of all gun deaths in the areas reviewed. Gabe Joselow has more from Nairobi.

VOA Blogs