Use of qPCR and genomic sequencing to diagnose Plasmodium ovale wallikeri malaria in a returned soldier in the setting of a negative rapid diagnostic assay.

Plasmodium ovale is one of several clinically relevant malaria species known to cause disease in humans. However, in contrast to Plasmodium falciparum and Plasmodium vivax, which are responsible for most cases of human malaria, P. ovale has a wide distribution but low prevalence in tropical regions. Here, we report the case of a soldier returning from Liberia with P. ovale wallikeri malaria. This case highlights the limitations of both microscopy and the malaria rapid diagnostic test for diagnosing infection with P. ovale and for distinguishing P. ovale wallikeri from P. ovale curtisi. To our knowledge, this is the first case report in which quantitative real-time polymerase chain reaction amplification using the Cytochrome B gene, coupled with genomic sequencing of the potra locus, was used for definitive diagnosis of P. ovale wallikeri malaria.