Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New research confirms potential deadly nature of emerging monkey malaria species in humans

11.09.2009
Researchers in Malaysia have identified key laboratory and clinical features of an emerging new form of malaria infection.

Researchers 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 South-east Asia - was widespread amongst humans in Malaysia. Subsequent reports in neighbouring South-east 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 per cent, 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 South-east 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."

Reference
Daneshvar C, et al. Clinical and laboratory features of human Plasmodium knowlesi infections. Clin Infect Dis. 2009;49(6):852-60.
Contact
Craig Brierley
Senior Media Officer
Wellcome Trust
T +44 (0)20 7611 7329
E c.brierley@wellcome.ac.uk
Notes for editors
The Wellcome Trust is the largest charity in the UK. It funds innovative biomedical research, in the UK and internationally, spending over £600 million each year to support the brightest scientists with the best ideas. The Wellcome Trust supports public debate about biomedical research and its impact on health and wellbeing.

Resni Mona | Research asia research news
Further information:
http://www.wellcome.ac.uk
http://www.wellcome.ac.uk/News/Media-office/Press-releases/2009/WTX056446.htm
http://www.researchsea.com

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>