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

Sydney Hostage-taker Failed to Manipulate Social Media

Gunman forced captives to use personal Facebook, YouTube accounts to issue his demands; online community helped flag messages, urged others not to share them More

UN Seeks $8.4 Billion to Help War-Hit Syrians

Effort aimed at helping Syrians displaced within their own country and those who've fled to neighboring ones More

Who Are the Pakistani Taliban?

It's an umbrella group of militant organizations whose objective is enforcement of Sharia in Pakistan 'whether through peace or war' 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.
Will Pakistan School Shooting Galvanize Pakistan Against Extremism?i
X
Ayesha Tanzeem
December 17, 2014 11:54 AM
The attack on a military school in Pakistan’s northwest city of Peshawar left 141 dead, including 132 children. Strong statements of condemnation poured in from across the world. The country announced three days of mourning, and the leadership, both political and military, promised retribution. VOA's Ayesha Tanzeem looks at how likely the Pakistani government is to clamp down on all extremist groups.
Video

Video Will Pakistan School Shooting Galvanize Pakistan Against Extremism?

The attack on a military school in Pakistan’s northwest city of Peshawar left 141 dead, including 132 children. Strong statements of condemnation poured in from across the world. The country announced three days of mourning, and the leadership, both political and military, promised retribution. VOA's Ayesha Tanzeem looks at how likely the Pakistani government is to clamp down on all extremist groups.
Video

Video ‘Anti-Islamization’ Marches Increase Tensions In Germany

Anti-immigrant rallies in Germany have been building in recent weeks, peaking Monday night in the city of Dresden where tens of thousands of people turned out to demonstrate against what they call the ‘Islamization’ of the West. Germany has offered asylum to more Syrian refugees than any other country, and this appears to have set off the protests. Henry Ridgwell reports from London.
Video

Video Aceh Rebuilt Decade After Tsunami, But Scars Remain

On December 26, 2004 there was an earthquake in the Indian Ocean so powerful it caused the Earth’s axis to wobble a few centimeters. Onshore on the island of Sumatra, the resulting tsunami was devastating. A decade later, VOA Correspondent Steve Herman reports from Banda Aceh, Indonesia, where although there is little remaining evidence of the physical devastation, the psychological scars among survivors remain.
Video

Video Refugees Living in Kenya Long for Peace in the Home Countries

Kenya is host to numerous refugees seeking safe haven from conflict. Immigrants from Somalia face challenges in their new lives in Kenya. Ahead of International Migrants Day (December 18) Lenny Ruvaga has more for VOA News from the Kenyan capital.
Video

Video Turkey's Authoritarianism Dismays Western Allies

The Turkish government has been defiant in the face of criticism at home and abroad for its raids targeting opposition media. The European Union on Monday expressed dismay after President Recep Tayyip Erdogan lashed out at Brussels for criticizing his government's action. Turkey's bid to be considered for EU membership has been on hold while critics accuse the NATO ally of increasingly authoritarian rule. Zlatica Hoke reports.
Video

Video US-China Year in Review: Hong Kong to Climate Change

The United States is pushing for a code of conduct to resolve territorial disputes in the South China Sea as it works to improve commercial ties with Beijing. VOA State Department correspondent Scott Stearns reports on a year of U.S. policy toward China from Hong Kong to climate change.
Video

Video Japanese Leader’s Election Win Raises Potential for Conflict with Neighbors

Japan’s Prime Minister Shinzo Abe and his allies easily won a two-thirds majority in parliament Sunday, even though the country has slipped into recession under his conservative policies. VOA’s Brian Padden reports from Seoul, that the prime minister’s victory will empower him to continue economic reforms but also pursue a nationalist agenda that will likely increase tensions with Japan’s neighbors.
Video

Video Nuba Mountain Families Hide in Caves to Escape Aerial Bombings

Despite ongoing peace talks between Sudan's government and the rebel Sudan People’s Liberation Movement-North, or SPLM-N, daily aerial attacks continue in South Kordofan province’s Nuba Mountains. Adam Bailes was there and reports for VOA that government forces are targeting civilian areas, rather than military positions, with their daily bombardments.

All About America

AppleAndroid