News / Health

Experimental Malaria Vaccine Weakens Parasite

A young girl with malaria rests in the inpatient ward of the Malualkon Primary Health Care Center in Malualkon, in the South Sudanese state of Northern Bahr el Ghazal, June 1, 2012.
A young girl with malaria rests in the inpatient ward of the Malualkon Primary Health Care Center in Malualkon, in the South Sudanese state of Northern Bahr el Ghazal, June 1, 2012.
Jessica Berman
Scientists are developing a vaccine against malaria that is designed to limit the illness in children who have been bitten by mosquitoes carrying the disease-causing organism.  They have discovered a protein that is essential for malaria parasites to cause severe illness.

With the protein, called SEA, the parasite is able to burst through infected red blood cells, ramping up disease symptoms. But malaria parasites deprived of SEA are trapped inside the cells where they wither away and are eventually eliminated from the body by the spleen.  

Researchers at Brown University in Providence, Rhode Island, and Boston Children’s Hospital in Massachusetts discovered the protein.  

Jonathan Kurtis is director of the Center for International Health Research at Rhode Island Hospital and lead author of the study which appears in the journal Science.

Kurtis says an experimental vaccine containing antibodies against the parasitic protein was developed and tested in mice.  Rodents that received the vaccine were only mildly sick and had fewer parasites in their bodies than untreated mice.

Next, Kurtis says investigators measured levels of antibodies to the SEA protein in a group of 785 Tanzanian children.

“And children with antibodies to our protein never got severe malaria - there were zero cases - as compared to children who did not have antibodies to our protein,” Kurtis said.
 
Malaria mortality rates, 2000 - 2012Malaria mortality rates, 2000 - 2012
x
Malaria mortality rates, 2000 - 2012
Malaria mortality rates, 2000 - 2012
Researchers then analyzed blood samples collected in 1997 from 140 children in Kenya.  Investigators found there were 50 percent fewer parasites in the serum of youngsters that produced antibodies to SEA during a high transmission season.  As with the Tanzanian children, there were also no severe cases of the disease in children with antibodies against the protein, according to Kurtis.

“And so the thought is by immunizing people with the SEA proteins, so that they make their own antibodies, they’ll be protected,” he added.

The next step, Kurtis says, is to test a laboratory-made SEA vaccine to see whether it works in primates.

Kurtis says he’s excited that researchers may be on the verge of an effective drug that lessens the severity of a malaria infection, but he’s also humbled.

“Our eye has to be on the prize.  And the prize is - you’ve got a child every 15 seconds, just during this phone conversation, you know dozens and dozens of children have died of malaria,” Kurtis said. "It’s just unbelievable.”

If the vaccine proves to be safe and effective in monkeys within the next  year, researchers expect they’ll move quickly to human vaccine trials.  

Kurtis says the goal eventually is to immunize youngsters in malaria-endemic regions at the same time they are vaccinated against other childhood illnesses.

You May Like

Karzai's Legacy: Missed Opportunities?

Afghanistan's president leaves behind a much different nation than the one he inherited, yet his legacy from 13 years in power is getting mixed reviews More

US Urges Restraint in Hong Kong Protests

Protesters angered by Beijing's decision to only approve candidates that it sanctions for Hong Kong's leadership elections in 2017 More

Archive of Forgotten UCLA Speeches Offers Snapshot of History

Recordings of prominent voices in social change, politics, science and literature from 1960s, early 1970s now available on YouTube More

This forum has been closed.
Comment Sorting
Comments
     
by: Donald Fraser Miles from: Elliot Lake, Canada
May 24, 2014 8:36 AM
My own theory on malaria which I communicated years ago is that the male mosquito creates protection against the malaria parasite. Only female mosquitos bite. It may be that the female mosquito bites in part to offload the malaria parasite from its own body. Male mosquito sex hormones may protect against or kill the malaria parasite. This is a theory which has had the opportunity to be tested. No confirmation of this theory has occurred. Thus it may not be correct. However, it is my theory on malaria.

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Treasure Hunters Seek 'Hidden Treasure' in Central Kenyai
X
Gabe Joselow
September 29, 2014 6:20 PM
Could a cave in a small village in central Kenya be the site of buried treasure? A rumor of riches, left behind by colonialists, has some residents dreaming of wealth, while others see it as a dangerous hoax. VOA's Gabe Joselow has the story.
Video

Video Treasure Hunters Seek 'Hidden Treasure' in Central Kenya

Could a cave in a small village in central Kenya be the site of buried treasure? A rumor of riches, left behind by colonialists, has some residents dreaming of wealth, while others see it as a dangerous hoax. VOA's Gabe Joselow has the story.
Video

Video Iran's Rouhani Skeptical on Syria Strikes

Iranian President Hassan Rouhani expressed skepticism Friday that U.S.-led airstrikes in Iraq and Syria could crush Islamic State militants. From New York, VOA’s Margaret Besheer reports the president was also hopeful that questions about Iran’s nuclear program could be resolved soon.
Video

Video US House Speaker: Congress Should Debate Authorization Against IS

As wave after wave of U.S. airstrikes target Islamic State militants, the speaker of the Republican-controlled House of Representatives says he would be willing to call Congress back into session to debate a formal, broad authorization for the use of military force. VOA’s Michael Bowman reports from Washington, where legislators left town 10 days ago for a seven-week recess.
Video

Video Ebola Patients Find No Treatment at Sierra Leone Holding Center

At a holding facility in Makeni, central Sierra Leone, dozens of sick people sit on the floor in an empty university building. They wait in filthy conditions. It's a 16-hour drive by ambulance to Kailahun Ebola treatment center. Adam Bailes was there and reports on what he says are some of the worst situations he has seen since the beginning of this Ebola outbreak. And he says it appears case numbers may already be far worse than authorities acknowledge.
Video

Video Identifying Bodies Found in Texas Border Region

Thousands of immigrants have died after crossing the border from Mexico into remote areas of the southwestern United States in recent years. Local officials in south Texas alone have found hundreds of unidentified bodies and buried them in mass graves in local cemeteries. Now an anthropologist and her students at Baylor University have been exhuming bodies and looking for clues to identify them. VOA’s Greg Flakus has more from Waco, Texas.
Video

Video Ebola Robs Liberians of Chance to Say Good-Bye to Loved Ones

In Liberia, where Ebola has killed more than 1,500 people, authorities have worked hard to convince people to allow specialized burial teams to take away dead bodies. But these safety measures, while necessary, make it hard for people to say good bye to their loved ones. VOA's Anne Look reports on the tragedy from Liberia.
Video

Video Reconstruction? What Reconstruction? Life After War in Gaza

It’s been a month since Israel and the Palestinians agreed to a ceasefire to end 52 days of an air and tank war that left 60,000 homes in Gaza damaged or destroyed and 110,000 homeless. Sharon Behn reports that lack of reconstruction is leading to despair.
Video

Video US, Saudi Arabia and UAE Hit Islamic State's Oil Revenue

The United States, Saudi Arabia and the United Arab Emirates have bombed oil facilities operated by Islamic State militants in Syria. It was a truly collaborative effort, with the two Arab countries dropping the majority of the bombs. The 12 refineries targeted were estimated to generate as much as $2 million per day for the terrorist group. VOA Pentagon correspondent Carla Babb has the story.
Video

Video Russia's Food Sanctions Raise Price Worries, Hopes for Domestic Production

Russia retaliated against Western sanctions imposed for its actions in Ukraine by halting food imports from the West. The temporary import ban on food from Australia, the European Union, Norway and North America has Russian consumers concerned that they could face a sharp increase in food prices. But in an ironic twist, the restrictions aimed at the Kremlin have made Russia's domestic food producers hopeful this can boost their business. VOA's Daniel Schearf reports from Moscow.
Video

Video Washington to Pyongyang: 'Shut This Evil System Down'

U.S. Secretary of State John Kerry is calling on North Korea to shut down prison camps and other human rights abuses following a United Nations Commission of Inquiry into "widespread and systematic human rights violations." VOA State Department Correspondent Scott Stearns reports from the United Nations.
Colonel Steve ‘Spiros’ Pisanos left Greece and came to the U.S. to learn to fly. He flew fighters for the Allies in World War II, narrowly escaping death multiple times.Colonel Steve ‘Spiros’ Pisanos left Greece and came to the U.S. to learn to fly. He flew fighters for the Allies in World War II, narrowly escaping death multiple times.

AppleAndroid