First case of human infection with Plasmodium knowlesi in Laos

Abstract

On July 17, 2016, a 12-year-old Laotian boy living in Bengvilay village, Sanamxay district, Attapeu province (adjacent to Cambodia) in Laos visited Bengvilay Health Center. He manifested malaria-like symptoms and signs such as high fever (40 o C), shivering, and nausea. The patient did not have a history of traveling outside of Attapeu province, Laos. The fever started 3 days before he visited the health center. He was diagnosed as having been infected with Plasmodium vivax malaria by a Rapid Diagnostic Test (RDT) kit (Malaria Ag Pf/Pv, Standard Diagnostics, Republic of Korea) at the health center, and a 3-day course of artemether/lumefantrine was prescribed. The patient recovered after the treatment. Prior to this episode, the patient had been recorded as having 4 previous malaria episodes that were diagnosed by the RDT kit, but detailed information, such as Plasmodium species and symptoms, was not recorded. The family used insecticide-treated bednets inside their home. The family was employed in agriculturally related jobs and occasionally went to the forest to collect foods and other necessities. The patient sometimes accompanied his family to the forest. A finger-prick blood sample was collected on a filter paper (Whatman FTA Classic Cards, GE Healthcare Life Science, United Kingdom) prior to the treatment, and we implemented a molecular approach to confirm the Plasmodium species by PCR and DNA sequencing.