Science Current Events | Science News | Brightsurf.com
 

'Benign' malaria key driver of human evolution in Asia-Pacific

September 05, 2012
Their finding challenges the widely-accepted theory that Plasmodium falciparum, which causes the most lethal form of malaria, is the only malaria parasite capable of driving genome evolution in humans. The study was published today in the journal PLOS Medicine.

Professor Ivo Mueller from the Walter and Eliza Hall Institute and Barcelona Centre for International Health Research (CRESIB) led the study, with colleagues from the Papua New Guinea Institute of Medical Research, Centre of Global Health and Diseases, US, and the University of Western Australia.

Malaria is a devastating parasitic disease that kills up to one million people a year. It is a major cause of poverty and a barrier to economic development. Approximately half of the world's population is at risk of malaria infection.

"Humans and malaria parasites have been co-evolving for thousands of years," Professor Mueller said. "Malaria has been a major force in the evolution of the human genome, with gene mutations that provide humans with some protection against the disease being preserved through natural selection because they aid in survival."

Professor Mueller said the study has challenged the perception that P. falciparum malaria is the only malaria species that affects human genome evolution. "It has long been assumed that Plasmodium falciparum, the species that causes the most severe disease and most deaths from malaria, is the most important driver of this gene selection in humans," Professor Mueller said. "Our results suggest that P. vivax malaria, though until recently widely considered to be a 'benign' form of malaria, actually causes severe enough disease to provide evolutionary selection pressures in the Asia-Pacific."

Professor Mueller said that the research team was interested in whether P. vivax malaria might be the cause of the unusually high rates of Southeast Asian ovalocytosis (SAO), a hereditary red blood cell disorder, in the Asia-Pacific region. "SAO occurs in approximately 10 to 15 per cent of the population in parts of the South West Pacific and is caused by a hereditary mutation in a single copy of a gene that makes a red blood cell membrane protein. This is almost an absurdly high frequency when you consider that inheriting two copies of the mutation is invariably fatal, so we figured it must confer a strong advantage to the carriers," he said.

The research team looked at the incidence of P. vivax and P. falciparum infections in three studies that included a total of 1975 children in Papua New Guinea aged 0-14 years. "We found that SAO-positive children were significantly protected against P. vivax infection, with 46 per cent reduction of clinical disease in infants with little or no immunity, and 52-55 per cent reduction in the risk of infection in older children. We also saw a significant decrease in parasite numbers in infants and older children, which is linked to a decrease in risk of clinical disease," Professor Mueller said.

The finding could have dramatic implications for future malaria vaccine design and development, Professor Mueller said. "Studying the mechanisms that cause SAO-positive people to be protected against P. vivax malaria could help us to better understand the mechanics of infection and help us to identify better targets for a malaria vaccine," he said.

Walter and Eliza Hall Institute


Related Malaria Current Events and Malaria News Articles


Skin patch could replace the syringe for disease diagnosis
Drawing blood and testing it is standard practice for many medical diagnostics. As a less painful alternative, scientists are developing skin patches that could one day replace the syringe.

Protein found in insect blood that helps power pests' immune responses
Pest insects may be sickened to learn to that researchers at Kansas State University have discovered a genetic mechanism that helps compromise their immune system.

Climate change alters the ecological impacts of seasons
If more of the world's climate becomes like that in tropical zones, it could potentially affect crops, insects, malaria transmission, and even confuse migration patterns of birds and mammals worldwide.

New theorem determines the age distribution of populations from fruit flies to humans
The initial motivation was to estimate the age structure of a fruit fly population, the result a fundamental theorem that can help determine the age distribution of essentially any group.

Study questions the prescription for drug resistance
In response to the rise of drug-resistant pathogens, doctors are routinely cautioned against overprescribing antimicrobials. But when a patient has a confirmed bacterial infection, the advice is to treat aggressively to quash the infection before the bacteria can develop resistance.

DNA 'bias' may keep some diseases in circulation, Penn biologists show
It's an early lesson in genetics: we get half our DNA from Mom, half from Dad.

Tropical disease prevalence in Latin America presents opportunity for US, Baker Institute expert says
Recently published prevalence estimates of neglected tropical diseases (NTDs) in five Latin American countries - Bolivia, Cuba, Ecuador, Nicaragua and Venezuela - could suggest a new direction for United States foreign policy in the region, according to a tropical-disease expert at Rice University's Baker Institute for Public Policy.

Dry roasting could help trigger peanut allergy
Dry roasted peanuts are more likely to trigger an allergy to peanuts than raw peanuts, suggests an Oxford University study involving mice.

A New Way to Prevent the Spread of Devastating Diseases
For decades, researchers have tried to develop broadly effective vaccines to prevent the spread of illnesses such as HIV, malaria, and tuberculosis.

Technique to model infections shows why live vaccines may be most effective
Vaccines against Salmonella that use a live, but weakened, form of the bacteria are more effective than those that use only dead fragments because of the particular way in which they stimulate the immune system, according to research from the University of Cambridge published today in the journal PLOS Pathogens.
More Malaria Current Events and Malaria News Articles

The Malaria Project: The U.S. Government's Secret Mission to Find a Miracle Cure

The Malaria Project: The U.S. Government's Secret Mission to Find a Miracle Cure
by Karen M. Masterson (Author)


A fascinating and shocking historical exposé, The Malaria Project is the story of America's secret mission to combat malaria during World War II—a campaign modeled after a German project which tested experimental drugs on men gone mad from syphilis.

American war planners, foreseeing the tactical need for a malaria drug, recreated the German model, then grew it tenfold. Quickly becoming the biggest and most important medical initiative of the war, the project tasked dozens of the country’s top research scientists and university labs to find a treatment to remedy half a million U.S. troops incapacitated by malaria.

Spearheading the new U.S. effort was Dr. Lowell T. Coggeshall, the son of a poor Indiana farmer whose persistent drive and curiosity led him to...

The Making of a Tropical Disease: A Short History of Malaria (Johns Hopkins Biographies of Disease)

The Making of a Tropical Disease: A Short History of Malaria (Johns Hopkins Biographies of Disease)
by Randall M. Packard (Author)


Malaria sickens hundreds of millions of people—and kills one to three million—each year. Despite massive efforts to eradicate the disease, it remains a major public health problem in poorer tropical regions. But malaria has not always been concentrated in tropical areas. How did other regions control malaria and why does the disease still flourish in some parts of the globe?From Russia to Bengal to Palm Beach, Randall Packard’s far-ranging narrative traces the natural and social forces that help malaria spread and make it deadly. He finds that war, land development, crumbling health systems, and globalization—coupled with climate change and changes in the distribution and flow of water—create conditions in which malaria's carrier mosquitoes thrive. The combination of these...

The Fever: How Malaria Has Ruled Humankind for 500,000 Years

The Fever: How Malaria Has Ruled Humankind for 500,000 Years
by Sonia Shah (Author)


In recent years, malaria has emerged as a cause célèbre for voguish philanthropists. Bill Gates, Bono, and Laura Bush are only a few of the personalities who have opened their pocketbooks in hopes of eradicating the scourge. How does a parasitic disease that we’ve known how to prevent for more than a century still infect three hundred million people every year, killing nearly one million of them? In The Fever, the journalist Sonia Shah sets out to answer this question, delivering a timely, inquisitive chronicle of the illness and its influence on human lives. The Fever captures the curiously fascinating, devastating history of this long-standing thorn in the side of humanity.

Little Things Make Big Differences: A Story about Malaria

Little Things Make Big Differences: A Story about Malaria
by John Nunes (Author)


Little Things Make Big Differences is a story about Rehema, a young girl who lives in the African country of Tanzania. When she was a baby, Rehema was infected with malaria, but because her parents were able to get treatment for her, she survived. In the book, Rehema describes what children in the United States can do to help fight malaria.

One little bite from one mosquito doesn't seem like a big thing, but if that mosquito carries the parasite that causes malaria, its bite can be very serious. Malaria is one of the most common infectious diseases, and it can be deadly. Each year, one million people die of malaria-that's one death every 30 seconds. In Africa, 75 percent of the malaria victims are children. Prevention is not only possible, but it's simple.



Author...

Quinine: Malaria and the Quest for a Cure That Changed the World

Quinine: Malaria and the Quest for a Cure That Changed the World
by Fiammetta Rocco (Author)


Quinine: The Jesuits discovered it. The Protestants feared it. The British vied with the Dutch for it, and the Nazis seized it. Because of quinine, medicine, warfare, and exploration were changed forever.For more than one thousand years, there was no cure for malaria. In 1623, after ten cardinals and hundreds of their attendants died in Rome while electing Urban VII the new pope, he announced that a cure must be found. He encouraged Jesuit priests establishing new missions in Asia and in South America to learn everything they could about how the local people treated the disease, and in 1631, an apothecarist in Peru named Agostino Salumbrino dispatched a new miracle to Rome. The cure was quinine, an alkaloid made from the bitter red bark of the cinchona tree.From the quest of the...

Humanity's Burden: A Global History of Malaria (Studies in Environment and History)

Humanity's Burden: A Global History of Malaria (Studies in Environment and History)
by James L.A. Webb Jr. (Author)


Humanity's Burden provides a panoramic overview of the history of malaria. It traces the long arc of malaria out of tropical Africa into Eurasia, its transfer to the Americas during the early years of the Columbian exchange, and its retraction from the middle latitudes into the tropics since the late nineteenth century. Adopting a broadly comparative approach to historical patterns and processes, it synthesizes research findings from the natural and social sciences and weaves these understandings into a narrative that reaches from the earliest evidence of malaria infections in tropical Africa up to the present. Written in a style that is easily accessible to non-specialists, it considers the significance of genetic mutations, diet, lifestyle, migration, warfare, palliative and curative...

The Malaria Capers: Tales of Parasites and People

The Malaria Capers: Tales of Parasites and People
by Robert S. Desowitz (Author)


"Reads like a murder mystery. . . . [Desowitz] writes with uncommon lucidity and verse, leaving the reader with a vivid understanding of malaria and other tropical diseases, and the ways in which culture, climate and politics have affected their spread and containment."—New York Times Why, Robert S. Desowitz asks, has biotechnical research on malaria produced so little when it had promised so much? An expert in tropical diseases, Desowtiz searches for answers in this provocative book.

End Malaria

End Malaria
by Michael Bungay Stanier (Editor)


End Malaria is more than a book, it’s a great cause.

At least $20 from each copy sold by us goes directly to Malaria No More to send a mosquito net to a family in need and to support life-saving work in the fight against malaria. Malaria No More, an international advocacy organization, is on a mission to end malaria related deaths by 2015.

In addition to saving lives, buying this book means you can enjoy essays by 62 of American’s favorite business authors, including Tom Peters, Nicholas Carr, Pam Slim, and Sir Ken Robinson. Organized into three main sections—Focus, Courage, Resilience—and eight subsections—Tap Your Strengths, Create Freedom, Love & Be Kind, Disrupt Normal, Take Small Steps, Embrace Systems, Get Physical, Collaborate—all essays in End...

Malaria, Poems

Malaria, Poems
by Cameron Conaway (Author)


Malaria kills nearly one million people each year. Hundreds of millions more are sickened by the disease, and many of them are permanently disabled. Billions are spent each year to understand it. Researchers know the molecular details of the interaction between the mosquito and our own red blood cells, and the myriad ways in which malaria impacts the global economy and the advancement of humanity. But what of the public? Though its story is told in thousands of articles and in hundreds of books, many in the developed world are unaware of how prevalent malaria still is. Malaria, Poems testifies to the importance of bridging the chasm between science and art. It adds thread to a tattered and tragic global narrative; it is poetry’s attempt to reawaken care in a cold case that keeps...

Malaria and the International Traveler

Malaria and the International Traveler
by CME Resource/NetCE


Malaria poses a particularly serious threat to U.S. travelers who lack immunity to it, and delayed diagnosis is a leading cause of death among malaria patients in the United States. The purpose of this course is to provide healthcare professionals with the information necessary to accurately identify, treat, and educate patients regarding the risks of malaria in order to protect those who may be exposed to the disease. In addition, members of the public may use this course to enhance their personal knowledge of the subject matter presented.

Upon completion of this course, you should be able to:

1. Describe the history and natural life cycle of malaria.
2. Identify how and where the transmission of malaria occurs.
3. Differentiate between uncomplicated...

© 2014 BrightSurf.com