Plasmodium knowlesi infection imported to Germany, January 2013.

Area of Science:

• Tropical medicine
• Parasitology
• Infectious diseases

Background:

• Plasmodium knowlesi is a simian malaria parasite originally found in macaques.
• Human infections with Plasmodium knowlesi were first recognized in Borneo and subsequently reported throughout Southeast Asia.
• The geographical range of Plasmodium knowlesi infections is expanding.

Observation:

• A case of Plasmodium knowlesi malaria was imported to Germany from Thailand.
• The patient did not use antimalarial chemoprophylaxis.
• The patient experienced daily fever attacks.

Findings:

• Microscopy initially suggested Plasmodium malariae due to the presence of trophozoites and gametocytes.
• Polymerase chain reaction (PCR) confirmed the diagnosis of Plasmodium knowlesi malaria.
• This case highlights the potential for imported simian malaria.

Implications:

• Increased global travel necessitates awareness of Plasmodium knowlesi as a potential cause of malaria outside endemic areas.
• Accurate diagnostic methods, including PCR, are crucial for identifying Plasmodium knowlesi, which can be misidentified by microscopy.
• This finding underscores the importance of considering non-falciparum malaria in febrile travelers returning from endemic regions.