Midtveisevaluering - Christel Gill Haanshus
PCR based Malaria diagnostics – Method development and application
Malaria is one of the leading infectious disease causing morbidity and death in tropical countries. Globally more than three billion people are exposed to malaria, and accordant to the World Health Organization, approximately 200 million malaria cases and 500 000 malaria deaths occurred in 2013. The last two decades the application of polymerase chain reaction (PCR) methods in detecting malaria has emerged, especially within research and epidemiology. Compared to microscopy, the gold standard in routine malaria diagnostic, PCR methods are superior in sensitivity and specificity. PCR can amplify a single copy of malaria DNA to a detectable level. However, the need to develop and improve malaria PCR techniques is still prominent. Wider deployment of sensitive molecular diagnostic tools is essential to detect submicroscopic malaria, and to better understand malaria epidemiology and transmission dynamics.
The PhD consists of four subprojects, two on method development and validation, and two based on the application of the validated methods. A conventional single-step PCR targeting the mitochondrial Plasmodium genome was developed, and showed to have a higher sensitivity in diagnosing malaria than routine microscopy and a nested 18S PCR reference method among returned travellers in Bergen, Norway (N=135). The conventional PCR method was applied in a multi-centre study to assess the malaria prevalence among patients with acute undifferentiated fever admitted to seven community hospitals across India (N=1416). In the third subproject, the conventional PCR was converted to a real-time PCR using SYBR green, and validated by employing well-defined patient material from the first subproject (N=115). The real-time PCR method is planned applied in a last subproject , where the main objective will be to perform quantitative analysis on a cohort of P. falciparum positive samples from Tanzania (Strøm et al. Malaria Journal 2013), with both high and low parasitaemia (N=76).