Plasmodium knowlesi detection methods for human infections—Diagnosis and surveillance

Diagnostic accuracy and limit of detection of ten malaria parasite lactate dehydrogenase-based rapid tests for Plasmodium knowlesi and P. falciparum

“…Current efforts to develop novel malaria RDTs or modify those currently available to improve specificity for P. knowlesi and other clinically relevant simian malaria species face considerable obstacles ( Yerlikaya et al., 2018 ) as manufacturers of existing commercial malaria RDTs do not often disclose which pLDH epitopes are bound by their proprietary antibodies ( Grigg et al., 2021 ). Current malaria RDT development is appropriately focused on developing highly-sensitive tests in order to facilitate elimination of P. falciparum and P. vivax , due to the increasingly recognized role that low-level asymptomatic infections have on sustaining transmission ( Stresman et al., 2020 ).…”

“…Other countries with a higher burden of human malaria, such as Indonesia ( Coutrier et al., 2018 ), India ( Tyagi et al., 2013 ), Cambodia ( Khim et al., 2011 ), Myanmar ( Jiang et al., 2010 ), and Thailand ( Putaporntip et al., 2009 ) have also reported P. knowlesi cases using molecular methods, with these cases initially being misidentified as other species using routine light microscopy. Due to similarities in morphology between P. knowlesi and other endemic Plasmodium species ( Lee et al., 2009 ), there are major limitations to microscopy as the primary method of diagnosis in endemic areas, with regional prevalence likely underestimated ( Barber et al., 2013b ; Grigg et al., 2021 ). Sensitive and specific malaria diagnostic tools are vital to ensure timely diagnosis, particularly in areas of high prevalence ( World Health Organization, 2011 ) where misidentification of P. knowlesi as other Plasmodium species can lead to delayed or inappropriate treatment and increased risk of fatal outcome ( Rajahram et al., 2019 ).…”

Diagnostic accuracy and limit of detection of ten malaria parasite lactate dehydrogenase-based rapid tests for Plasmodium knowlesi and P. falciparum

“…The RDTs evaluated in this study showed variable performance for detection of P. knowlesi , with many demonstrating sufficient sensitivity for diagnostic use despite the inherent limitations in specificity against other Plasmodium species. Current efforts to develop novel malaria RDTs or modify those currently available to improve specificity for P. knowlesi and other clinically relevant simian malaria species face considerable obstacles (26) as manufacturers of existing commercial malaria RDTs do not often disclose which pLDH epitopes are bound by their proprietary antibodies (11). Current malaria RDT development is appropriately focused on developing highly-sensitive tests in order to facilitate elimination of P. falciparum and P. vivax , due to the increasingly recognized role that low-level asymptomatic infections have on sustaining transmission (56).…”

“…Other countries with a higher burden of human malaria, such as Indonesia (5), India (6), Cambodia (7), Myanmar (8), and Thailand (9) have also reported P. knowlesi cases using molecular methods, with these cases initially being misidentified as other species using routine light microscopy. Due to similarities in morphology between P. knowlesi and other endemic Plasmodium species (10), there are major limitations to microscopy as the primary method of diagnosis in endemic areas, with regional prevalence likely underestimated (11, 12). Sensitive and specific malaria diagnostic tools are vital to ensure timely diagnosis, particularly in areas of high prevalence (13) where misidentification of P. knowlesi as other Plasmodium species can lead to delayed or inappropriate treatment and increased risk of fatal outcome (14).…”

“…Other countries with a higher burden of human malaria, such as Indonesia (5), India (6), Cambodia (7), Myanmar (8), and Thailand (9) have also reported P. knowlesi cases using molecular methods, with these cases initially being misidentified as other species using routine light microscopy. Due to similarities in morphology between P. knowlesi and other endemic Plasmodium species (10), there are major limitations to microscopy as the primary method of diagnosis in endemic areas, with regional prevalence likely underestimated (11,12).…”