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
TEXT SIZE - +
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

Photogallery Pope's Easter Prayer: Peace in Ukraine, Syria

Pontiff also calls for end to terrorist acts in Nigeria, violence in Iraq, and success in peace talks between Israelis and Palestinians More

Abdullah Holds Lead in Afghan Presidential Election

Country's Election Commission says that with half of the ballots counted, former FM remains in the lead with 44 percent of the vote More

Russia-Ukraine Crisis Could Trigger Cyber War

As tensions between Kyiv and Moscow escalate, so too has frequency of online attacks targeting government, news and financial sites 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.
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