This webinar discusses how new quantitative polymerase chain reaction (qPCR) and reverse transcription qPCR (RT-qPCR) tests can accelerate the discovery and development of much-needed anti-malarial drugs and vaccines.
Novel anti-malaria drugs and vaccines are currently evaluated using the Controlled Human Malaria Infection (CHMI) model, in which human volunteers receive a candidate drug or vaccine and are "challenged" with live Plasmodium falciparum sporozoites. Participants are then followed closely during the ensuing month, and if investigators detect the presence of malaria parasites in peripheral blood, it can indicate that the drug or vaccine was ineffective.
Historically, the gold standard test for erythrocyte stage Plasmodium infection has been microscopic examination of thick blood smears (TBS), which is analytically sensitive to 5-10 parasites per microliter of whole blood under ideal conditions. Because participants can be symptomatic prior to becoming TBS-positive, CHMI studies traditionally housed participants in a hospital ward or hotel during the potential symptomatic period.
More recently, qPCR/RT-qPCR-based tests have improved the analytical sensitivity of infection detection by several orders of magnitude and now permit pre-symptomatic infection detection. Such tests accelerate infection detection compared to TBS and enable CHMI studies to be conducted without domiciling participants.
In this webinar, Sean Murphy of the University of Washington discusses efforts to improve the limit of detection for Plasmodium 18S rRNA/rDNA assays to 10-20 parasites per milliliter of blood. His presentation describes how such tests have reduced the costs, complexity, and risks of CHMI studies by accelerating infection detection and will detail external quality assurance efforts between laboratories that corroborate these diagnostic improvements.