 |
|
New research confirms potential deadly nature of emerging new monkey malaria species in humans
September 10, 2009Researchers in Malaysia have identified key laboratory and clinical features of an emerging new form of malaria infection. The research, funded by the Wellcome Trust, confirms the potentially deadly nature of the disease.
Malaria kills more than a million people each year. It is caused by malaria parasites, which are injected into the bloodstream by infected mosquitoes. Of the four species of malaria that commonly cause disease in humans, Plasmodium falciparum, found most commonly in Africa, is the most deadly. P. malariae, found in tropical and sub-tropical regions across the globe, has symptoms that are usually less serious.
Recently, researchers at the University Malaysia Sarawak, led by Professors Balbir Singh and Janet Cox-Singh, showed that P. knowlesi, a malaria parasite previously thought to mainly infect only monkeys - in particular long-tailed and pig-tailed macaques found in the rainforests of Southeast Asia - was widespread amongst humans in Malaysia. Subsequent reports in neighbouring Southeast Asian countries have led to the recognition of P. knowlesi as the fifth cause of malaria in humans.
Now, in a study published in the journal Clinical Infectious Diseases, Professors Singh and Cox-Singh, together with colleagues from University Malaysia Sarawak, Kapit Hospital and the University of Western Australia, have published the first detailed prospective study of the clinical and laboratory features of human P. knowlesi infections.
"P. knowlesi malaria can easily be confused with P. malariae since these two parasites look similar by microscopy, but the latter causes a benign form of malaria," says Professor Singh. "In fact, because the P. knowlesi parasites reproduce every twenty four hours in the blood, the disease can be potentially fatal, so early diagnosis and appropriate treatment is essential. Understanding the most common features of the disease will be important in helping make this diagnosis and in planning appropriate clinical management."
The researchers initially recruited over 150 patients admitted to Kapit Hospital in Sarawak, Malaysian Borneo, between July 2006 and January 2008 who had tested positive with a blood film slide for Plasmodium species. Using molecular detection methods, P. knowlesi was found to be by far the most common infection amongst these patients, accounting for over two-thirds of all cases.
As with other types of malaria in humans, P. knowlesi infections resulted in a wide spectrum of disease. Most cases of infection were uncomplicated and easily treated with chloroquine and primaquine, two commonly used anti-malarial drugs. However, around one in ten patients had developed complications and two died. Complications included breathing difficulties and kidney problems (including kidney failure in a small number of cases), which are also common in severe P. falciparum cases. Although the researchers saw a case fatality rate of just under 2%, which makes P. knowlesi malaria as deadly as P. falciparum malaria, they stress that an accurate fatality rate is hard to determine given the relatively small number of cases studied so far.
All of the P. knowlesi patients - including those with uncomplicated malaria - had a low blood platelet count. In other human forms of malaria, this would only be expected in less than eight out of ten cases. In addition, the P. knowlesi platelet counts tended to be significantly lower than for other malarias. However, even though blood platelets are essential for blood clotting, no cases of excessive bleeding or problems with clotting were identified. The researchers believe the low blood platelet count could be used as a potential feature for diagnosis of P. knowlesi infections.
Recently, there have been cases of European travellers to Malaysia and an American traveller to the Philippines being admitted into hospital with knowlesi malaria following their return home.
"The increase in tourism in Southeast Asia may mean that more cases are detected in the future, including in Western countries," says Professor Singh. "Clinicians assessing a patient who has visited an area with known or possible P. knowlesi transmission should be aware of the diagnosis, clinical manifestations, and rapid and potentially serious course of P. knowlesi malaria."
Wellcome Trust
Now, in a study published in the journal Clinical Infectious Diseases, Professors Singh and Cox-Singh, together with colleagues from University Malaysia Sarawak, Kapit Hospital and the University of Western Australia, have published the first detailed prospective study of the clinical and laboratory features of human P. knowlesi infections.
"P. knowlesi malaria can easily be confused with P. malariae since these two parasites look similar by microscopy, but the latter causes a benign form of malaria," says Professor Singh. "In fact, because the P. knowlesi parasites reproduce every twenty four hours in the blood, the disease can be potentially fatal, so early diagnosis and appropriate treatment is essential. Understanding the most common features of the disease will be important in helping make this diagnosis and in planning appropriate clinical management."
The researchers initially recruited over 150 patients admitted to Kapit Hospital in Sarawak, Malaysian Borneo, between July 2006 and January 2008 who had tested positive with a blood film slide for Plasmodium species. Using molecular detection methods, P. knowlesi was found to be by far the most common infection amongst these patients, accounting for over two-thirds of all cases.
As with other types of malaria in humans, P. knowlesi infections resulted in a wide spectrum of disease. Most cases of infection were uncomplicated and easily treated with chloroquine and primaquine, two commonly used anti-malarial drugs. However, around one in ten patients had developed complications and two died. Complications included breathing difficulties and kidney problems (including kidney failure in a small number of cases), which are also common in severe P. falciparum cases. Although the researchers saw a case fatality rate of just under 2%, which makes P. knowlesi malaria as deadly as P. falciparum malaria, they stress that an accurate fatality rate is hard to determine given the relatively small number of cases studied so far.
All of the P. knowlesi patients - including those with uncomplicated malaria - had a low blood platelet count. In other human forms of malaria, this would only be expected in less than eight out of ten cases. In addition, the P. knowlesi platelet counts tended to be significantly lower than for other malarias. However, even though blood platelets are essential for blood clotting, no cases of excessive bleeding or problems with clotting were identified. The researchers believe the low blood platelet count could be used as a potential feature for diagnosis of P. knowlesi infections.
Recently, there have been cases of European travellers to Malaysia and an American traveller to the Philippines being admitted into hospital with knowlesi malaria following their return home.
"The increase in tourism in Southeast Asia may mean that more cases are detected in the future, including in Western countries," says Professor Singh. "Clinicians assessing a patient who has visited an area with known or possible P. knowlesi transmission should be aware of the diagnosis, clinical manifestations, and rapid and potentially serious course of P. knowlesi malaria."
Wellcome Trust
Malaria Current Events and Malaria News RSSOn the Trail of a Vaccine for Lyme Disease: Yale Researchers Target Tick Saliva
A protein found in the saliva of ticks helps protect mice from developing Lyme disease, Yale researchers have discovered. The findings, published in the November 19 issue of Cell Host & Microbe, may spur development of a new vaccine against infection from Lyme disease, which is spread through tick bites.
Research calls for better assessment of tests for tuberculosis, HIV/AIDS and malaria
A rapid and accurate diagnosis is the first step towards treatment in the fight against infectious disease.
Small nanoparticles bring big improvement to medical imaging
If you're watching the complex processes in a living cell, it is easy to miss something important-especially if you are watching changes that take a long time to unfold and require high-spatial-resolution imaging.
Prioritizing low-cost, simple health measures would save 2.5 million child lives a year
Almost a third of the children under age five who die each year could be saved if governments rebalance health spending to ensure low-cost, simple interventions such as safe water and hygiene, bed nets and basic maternal and newborn care, leading aid agency World Vision said today. Currently, 8.8 million children a year die before age five, most of preventable causes.
Drug industry, nonprofits join forces to fight world's neglected diseases
Drug companies and nonprofit organizations are joining forces to develop new drugs and vaccines to target so-called "neglected" diseases that claim millions of lives in the developing world each year.
U.S. and European Experts Applaud Creation of New Transatlantic Task Force on Global Antibiotic Resistance Threat
Experts on both sides of the Atlantic applaud President Barack Obama and Swedish Prime Minister Fredrik Reinfeldt, representing the European Union (EU) Presidency, for establishing a transatlantic task force to address antibiotic resistance, an urgent and growing problem that threatens patient safety and public health worldwide.
1930s drug slows tumor growth
Drugs sometimes have beneficial side effects. A glaucoma treatment causes luscious eyelashes. A blood pressure drug also aids those with a rare genetic disease.
DNA barcodes: Creative new uses span health, fraud, smuggling, history, more
The scientific ability to quickly and accurately identify species through DNA "barcoding" is being embraced and applied by a growing legion of global authorities - from medical and agricultural researchers to police and customs authorities to palaeontologists and others.
PATH Malaria Vaccine Initiative shares strategy for developing 'next-generation' malaria vaccines
Marking its tenth anniversary year, the PATH Malaria Vaccine Initiative (MVI) today unveiled a new strategy that sets the stage for an aggressive push targeting the long-term goal of eliminating and eradicating malaria. Malaria is one of the world's deadliest infectious diseases, killing nearly 900,000 people a year, most of them children in sub-Saharan Africa.
Global challenges and opportunities in fighting HIV/AIDS and neglected diseases
Responding to the HIV/AIDS pandemic and tackling so-called neglected tropical diseases are the focus of the November/December 2009 edition of Health Affairs.
More Malaria Current Events and Malaria News Articles
 |
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... |
 |
The Malaria Capers : More Tales of Parasites and People, Research and Reality 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. . |
 |
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... |
 |
Compiled 1981-1984 by Malaria! |
 |
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 laugh-out-loud funny 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 arrives at the Peace Corps office–sporting her best safari chic attire –to casually look into the steps one might take if one were to become a global humanitarian, a la Angelina Jolie. But when Eve meets John, her dashing young Peace Corps recruiter, all her ambivalence flies out the window. She absolutely must join the Peace Corps -... |
 |
Parasites! - The Malaria Parasite by Sheila Wyborny (Author) Malaria is a serious disease caused by a tiny mosquito-borne parasite called Plasmodium. It once affected entire empires, but thanks to the work of health organizations, malaria is now mostly confined to warm, moist climates. Scientists are still at work today, however, developing methods of curing the disease and destroying its carriers. |
![GIANTmicrobes: Malaria (Plasmodium Falciparum) [Toy]](http://ecx.images-amazon.com/images/I/21%2BeHMzjARL._SL160_.jpg) |
GIANTmicrobes: Malaria (Plasmodium Falciparum) [Toy] by Giant Microbes GIANTmicrobes are fun and educationala great way to learn about various health topics and the microscopic critters that are found in and around us. Each microbe character is 5-7 in size--over a million times their actual size! Perfect for teachers, parents and budding scientiststhey also make humorous gifts. Each microbe comes with an information tag including scientific name, an image of the actual microbe, and a mini history and science lesson. Not suitable for children under 3 years. Our products are made by top manufacturers who care about toy safety, quality and value. Your order will ship factory fresh directly from our warehouse to your door. We carefully inspect and beautifully package every order before shipment to ensure that you receive high quality products that are... |
 |
Malaria: Fever Wars Starring: Artist Not Provided |
 |
Molecular Approaches to Malaria by Irwin W. Sherman (Editor) "Molecular Approaches to Malaria" provides an overview of the rapid and significant developments that have occurred in malaria research, including the 2002 genome sequencing of Plasmodium falciparum and its mosquito vector, Anopheles gambiae. This work: provides a concise source of up-to-date research findings; appeals to a diverse audience, including malaria researchers, teachers, investigators, and public health professionals; offers contributions by recognized malaria researchers with practical experience; and, presents comprehensive coverage of topics including a clearly written introduction to Plasmodium molecular biology. |
 |
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 becomes vulnerable, how professionals came to know about the parasite and learned how to fight them, and how people view the disease and came to the point where they could understand and support the struggle... |
| © 2009 BrightSurf.com |