'Benign' malaria key driver of human evolution in Asia-PacificSeptember 04, 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 Articles:
Malaria is a global killer and a world health concern.
Scientists have discovered a gene that allows to double the production of artemisinin in the Artemisia annua plant.
EPFL scientists have fully modeled the metabolism of the deadliest malaria parasite.
Should we commit to eradicate malaria worldwide, asks a debate article published by The BMJ today?
An investigational malaria vaccine given intravenously was well-tolerated and protected a significant proportion of healthy adults against infection with Plasmodium falciparum malaria -- the deadliest form of the disease -- for the duration of the malaria season, according to new findings published in the Feb.
Malaria mosquitoes prefer to feed -- and feed more -- on blood from people infected with malaria.
A lineage of multidrug resistant P. falciparum malaria superbugs has widely spread and is now established in parts of Thailand, Laos and Cambodia, causing high treatment failure rates for the main falciparum malaria medicines, artemisinin combination therapies (ACTs), according to a study published today in The Lancet Infectious Diseases.
The goal of eliminating malaria in countries like India could be more achievable if mosquito-control efforts take into account the relationship between mosquitoes and cattle, according to an international team of researchers.
Giving preventive antimalarial drugs to children up to age 10 during active malaria season reduced the cases of malaria in that age group and lowered the malaria incidence in adults, according to a randomized trial carried out in Senegal and published in PLOS Medicine by researchers from the Université Cheikh Anta Diop, Senegal, the London School of Hygiene & Tropical Medicine, UK, and other collaborators.
OIST researchers reconstruct the 3-D structure of a malaria protein in combination with human antibodies.
Related Malaria Reading:
The Fever: How Malaria Has Ruled Humankind for 500,000 Years
by Sonia Shah (Author)
In recent years, malaria has emerged as a cause celebre for voguish philanthropists. Bill Gates, Bono, and Laura Bush are only a few of the personalities who have lent their names--and opened their pocketbooks--in hopes of stopping the disease. Still, in a time when every emergent disease inspires waves of panic, why aren't we doing more to tame one of our oldest foes? And how does a pathogen that we've known how to prevent for more than a century still infect 500 million people every year, killing nearly one million of them?
In The Fever, journalist Sonia Shah sets out to answer those... View Details
The Malaria Project: The U.S. Government's Secret Mission to Find a Miracle Cure
by Karen M. Masterson (Author)
A shocking exposé of America’s secret mission to combat malaria during World War II with a campaign that tested experimental drugs on men gone mad from syphilis.
Foreseeing the need for a malaria drug, American war planners re-created Germany’s research model, then grew it tenfold. Spearheading the effort, Dr. Lowell T. Coggeshall recruited private corporations as well as chemists from Harvard and Johns Hopkins to make novel compounds, which were then tested on human subjects.
By 1943, a dozen strains of malaria were injected into mental health patients and convicted... View Details
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... View Details
Malaria Dreams: An African Adventure
by Stuart Stevens (Author)
While attempting to transfer a friend's Land Rover from the Central African republic to Europe, two travel companions experience various adventures and hijinks in such locales as Lake Chad, Timbuktu, and the Sahara View Details
First Comes Love, then Comes Malaria: How a Peace Corps Poster Boy Won My Heart and a Third World Adventure Changed My Life
by Eve Brown-Waite (Author)
In this hilarious memoir, a pampered city girl falls head over little black heels in love with a Peace Corps poster boy and follows him— literally to the ends of the earth.
Eve Brown always thought she would join the Peace Corps someday, although she secretly worried about life without sushi, frothy coffee drinks and air conditioning. But with college diploma in hand, it was time to put up or shut up. So with some ambivalence she arrived at the Peace Corps office, sporting her best safari chic attire, to casually look into the steps one might take to become a global... View Details
Malaria: Poverty, Race, and Public Health in the United States
by Margaret Humphreys (Author)
In Malaria: Poverty, Race, and Public Health in the United States, Margaret Humphreys presents the first book-length account of the parasitic, insect-borne disease that has infected millions and influenced settlement patterns, economic development, and the quality of life at every level of American society, especially in the south.
Humphreys approaches malaria from three perspectives: the parasite's biological history, the medical response to it, and the patient's experience of the disease. It addresses numerous questions including how the parasite thrives and eventually... View Details
The Long Struggle against Malaria in Tropical Africa
by James L. A. Webb Jr (Author)
The Long Struggle Against Malaria in Tropical Africa investigates the changing entomological, parasitological, and medical understandings of vectors, parasites, and malarial disease that have shaped the programs of malaria control and altered the transmission of malarial infections. It examines the history of malaria control and eradication in the contexts of racial thought, population movements, demographic growth, economic change, urbanization, warfare, and politics. It will be useful for students of medicine and public health, for those who are involved with malaria research studies, and... View Details
by Mick Isle (Author)
Recounts the history and effects of malaria, describes how the disease spreads, and offers information about diagnosis, treatment, and the threat of malaria in the modern world. View Details
PLAQUENIL Tablet: Prevents and Treats Acute Attacks of Malaria; and also Used to Treat Lupus and Rheumatoid Arthritis
by James Lee Anderson (Author)
“Although, your health condition may impact your everyday life, do not let it define who you are.” PLAQUENIL (hydroxychloroquine) is used to prevent and to treat malaria and to treat some conditions such as liver disease caused by protozoa. It is also used in the treatment of arthritis to help relieve inflammation, swelling, stiffness, and joint pain and to help control the symptoms of lupus erythematosus (lupus; SLE). Hydroxychloroquine belongs to the family of medicines called antiprotozoals. Protozoa are tiny, one-celled animals. Some are parasites that can cause many different kinds... View Details
Spatial Agent-Based Simulation Modeling in Public Health: Design, Implementation, and Applications for Malaria Epidemiology (Wiley Series in Modeling and Simulation)
by S. M. Niaz Arifin (Author), Gregory R. Madey (Author), Frank H. Collins (Author)
Presents an overview of the complex biological systems used within a global public health setting and features a focus on malaria analysis
Bridging the gap between agent-based modeling and simulation (ABMS) and geographic information systems (GIS), Spatial Agent-Based Simulation Modeling in Public Health: Design, Implementation, and Applications for Malaria Epidemiology provides a useful introduction to the development of agent-based models (ABMs) by following a conceptual and biological core model of Anopheles gambiae for malaria epidemiology. Using spatial... View Details