There have been reports in Korea of imported malaria cases of four Plasmodium species, but there has been no report of imported Plasmodium ovale malaria confirmed by molecular biological methods. We report an imported case of that was confirmed by Wright-Giemsa-stained peripheral blood smear and nested polymerase chain reaction targeting the small subunit ribosomal RNA gene. The amplified DNA was sequenced and compared with other registered P. ovale isolates. The isolate in this study was a member of the classic type group. The patient was a 44-yr-old male who had worked as a woodcutter in Cote d'Ivoire in tropical West Africa. He was treated with hydroxychloroquine and primaquine and discharged following improvement. In conclusion, P. ovale should be considered as an etiology in the imported malaria in Korea, because the number of travelers to P. ovale endemic regions has recently increased.
Sequence Analysis, DNA ; Polymerase Chain Reaction ; Plasmodium ovale/*genetics ; Male ; Malaria/*diagnosis/etiology ; Humans ; Genes, rRNA ; Adult

In contrast to the gradual reduction in the number of locally transmitted malaria cases in China, the number of imported malaria cases has been increasing since 2008. Here, we report a case of a 39-year-old Chinese man who acquired Plasmodium ovale wallikeri infection while staying in Ghana, West Africa for 6 months in 2012. Microscopic examinations of Giemsa-stained thin and thick blood smears indicated Plasmodium vivax infection. However, the results of rapid diagnostic tests, which were conducted 3 times, were not in agreement with P. vivax. To further check the diagnosis, standard PCR analysis of the small-subunit rRNA gene was conducted, based on which a phylogeny tree was constructed. The results of gene sequencing indicated that this malaria is a variant of P. ovale (P. ovale wallikeri). The infection in this patient was not a new infection, but a relapse of the infection from the one that he had contracted in West Africa.
Adult ; Azure Stains ; Base Sequence ; China ; DNA, Protozoan/chemistry/genetics ; DNA, Ribosomal/chemistry/genetics ; Ghana ; Humans ; Malaria/*diagnosis/parasitology ; Male ; Molecular Sequence Data ; Phylogeny ; Plasmodium ovale/*classification/genetics/isolation & purification ; Polymerase Chain Reaction ; Recurrence ; Sequence Analysis, DNA ; Travel

Malaria is a parasitic infection caused by Plasmodium species. Most of the imported malaria in Korea are due to Plasmodium vivax and Plasmodium falciparum, and Plasmodium ovale infections are very rare. Here, we report a case of a 24-year-old American woman who acquired P. ovale while staying in Ghana, West Africa for 5 months in 2010. The patient was diagnosed with P. ovale malaria based on a Wright-Giemsa stained peripheral blood smear, Plasmodium genus-specific real-time PCR, Plasmodium species-specific nested PCR, and sequencing targeting 18S rRNA gene. The strain identified had a very long incubation period of 19-24 months. Blood donors who have malaria with a very long incubation period could be a potential danger for propagating malaria. Therefore, we should identify imported P. ovale infections not only by morphological findings but also by molecular methods for preventing propagation and appropriate treatment.
Blood/parasitology ; DNA, Protozoan/chemistry/genetics ; Female ; Ghana ; Humans ; Korea ; Malaria/*diagnosis/parasitology/*pathology ; Microscopy ; Plasmodium ovale/*isolation & purification ; Polymerase Chain Reaction ; RNA, Ribosomal, 18S/genetics ; Sequence Analysis, DNA ; *Travel ; Young Adult