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Human Infections with Plasmodium knowlesi, the Philippines
Jennifer Luchavez1, Fe Espino, Peter Curameng
1Research Institute for Tropical Medicine - Parasitology, Fillinvest Compound, Alabang, Muntinlupa City, Muntinlupa 1781, the Philippines. jluchavez@yahoo.com
Emerging Infectious Diseases
|April 29, 2008
Summary
Five human cases of Plasmodium knowlesi, a simian malaria parasite, were confirmed in Palawan, Philippines. This zoonotic malaria is now documented across a wider area in Palawan, indicating local transmission.
Area of Science:
- Medical Entomology
- Infectious Diseases
- Parasitology
Background:
- Plasmodium knowlesi is a simian malaria parasite that can infect humans, posing a zoonotic risk.
- Human infections with P. knowlesi have been reported in Southeast Asia, but its distribution in the Philippines was not well-defined.
Purpose of the Study:
- To confirm and document human cases of Plasmodium knowlesi infection in Palawan, Philippines.
- To assess the geographical spread and autochthonous nature of P. knowlesi zoonotic malaria in the region.
Main Methods:
- Nested PCR was used to confirm Plasmodium knowlesi infection in human blood samples.
- Case identification and geographical data collection were performed in Palawan.
Main Results:
- Five human cases of P. knowlesi infection were confirmed.
- The cases were distributed across a significant area of Palawan, suggesting wider endemicity.
- The findings indicate autochthonous transmission of P. knowlesi in the Philippines.
Conclusions:
- Plasmodium knowlesi zoonotic malaria is present and spreading in Palawan, Philippines.
- Nested PCR is a reliable method for diagnosing P. knowlesi infections.
- Continued surveillance is necessary to monitor the spread of this zoonotic parasite.
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