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Plasmodium knowlesi: the emerging zoonotic malaria parasite
Spinello Antinori1, Laura Galimberti, Laura Milazzo
1Department of Biomedical and Clinical Sciences Luigi Sacco, III Division of Infectious Diseases Luigi Sacco Hospital, Università degli Studi di Milano, Italy. spinello.antinori@unimi.it
Acta Tropica
|October 24, 2012
Summary
Plasmodium knowlesi malaria, initially found in monkeys, now causes significant human cases in Southeast Asia. Severe symptoms and fatalities occur, but chloroquine is effective for uncomplicated infections.
Area of Science:
- Medical Parasitology
- Infectious Diseases
- Tropical Medicine
Background:
- Plasmodium knowlesi, a simian malaria parasite, was historically used experimentally in humans and later identified as a cause of natural human infections.
- First documented human infection in 1965, P. knowlesi gained prominence in 2004 due to a high prevalence in Malaysian Borneo, highlighting its zoonotic potential.
- Recent findings indicate P. knowlesi is widespread across Southeast Asia, necessitating its consideration in febrile travelers returning from endemic forested regions.
Purpose of the Study:
- To review the historical context and current understanding of Plasmodium knowlesi infections in humans.
- To emphasize the diagnostic importance of P. knowlesi in travelers presenting with fever after visiting Southeast Asian forests.
- To outline the clinical spectrum, complications, and treatment of P. knowlesi malaria.
Main Methods:
- Literature review of historical and contemporary reports on Plasmodium knowlesi.
- Analysis of epidemiological data on human P. knowlesi cases in Southeast Asia.
- Summary of clinical manifestations, complications, and treatment guidelines for P. knowlesi malaria.
Main Results:
- Plasmodium knowlesi is a significant cause of human malaria in Southeast Asia, accounting for a substantial proportion of cases in certain regions.
- Severe P. knowlesi malaria occurs in 6-9% of cases, with a 3% fatality rate, frequently presenting with respiratory distress, renal failure, and shock.
- Chloroquine is the recommended treatment for uncomplicated P. knowlesi malaria.
Conclusions:
- Plasmodium knowlesi is an emerging zoonotic pathogen of global health importance.
- Early diagnosis and appropriate treatment are crucial for managing P. knowlesi malaria and preventing severe outcomes.
- Increased awareness and consideration of P. knowlesi in the differential diagnosis of febrile illnesses in travelers are warranted.
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