Diagnosis and Molecular Analysis on Imported Plasmodium ovale curtisi and P. ovale wallikeri Malaria Cases from West and South Africa during 2013-2016

Abstract

Majority of the imported malaria cases in Korea is attributed to <i>Plasmodium falciparum</i> and <i>P. vivax</i> infections, whereas <i>P. malariae</i> and <i>P. ovale</i> infections are very rare. Falciparum and ovale malaria are mostly imported from Africa, while most of the vivax malaria cases are imported from Southeast Asia. Here, we report 6 Korean imported ovale malaria cases (4 males and 2 females) who had visited in Africa during 2013-2016. These subjects were diagnosed with <i>P. ovale</i> based on microscopic findings, <i>Plasmodium</i> species-specific nested-PCR, and phylogenetic clade using 18S rRNA gene sequences. We identified 2 <i>P. ovale</i> subtypes, 1 <i>P. ovale curtisi</i> (classic type) and 5 <i>P. ovale wallikeri</i> (variant type). All patients were treated with chloroquine and primaquine, and no relapse or recrudescence was reported for 1 year after treatment. With increase of travelers to the countries where existing Plasmodium species, the risk of <i>Plasmodium</i> infection is also increasing. Molecular monitoring for imported malaria parasites should be rigorously and continuously performed to enable diagnosis and certification of <i>Plasmodium</i> spp.