Dr. Lisa Reimer is a postdoctoral fellow with Case Western Reserve University (CWRU) Center for Global Health and Diseases. Since February 2009 she has been conducting entomological studies at the Papua New Guinea Institute of Medical Research (PNGIMR). She has demonstrated strengths as a vector biologist in the field and laboratory and successfully leads a research team of Papua New Guinean scientists, technicians and students. In order to meet her long-term career objectives as an independent investigator researching malaria transmission dynamics, she requires mentorship in the areas of malaria epidemiology and disease transmission. Further training in statistics, study design and research ethics will allow her to develop skills necessary to conduct competitive and comprehensive research. Drs. Peter Zimmerman from CWRU and Ivo Mueller from PNGIMR will assist the candidate in developing an independent research career through targeted training activities and by implementing the research proposed. Co-mentor Dr. Jetsumon Prachumsri of the Armed Forces Research Institute of Medical Science (AFRIMS) will provide specific transmission biology training to the candidate. CWRU and PNGIMR have a long history of collaboration in malaria research and training. Dr. Zimmerman's lab has worked closely with Dr. Mueller's lab over the last ten years to strengthen the molecular epidemiology program at PNGIMR and to establish training curricula for Fogarty International Center sponsored programs. Dr. Reimer's background in mosquito biology and the proposed mentorship in malaria epidemiology and transmission will make it possible for her to complete novel research in transmission dynamics. The Anopheles punctulatus complex includes 12 species of mosquitoes, encompassing many of the major malaria vectors in Papua New Guinea. Many of the species within this complex are isomorphic, and it is only recently that molecular techniques have been developed to aid in identification. In addition, four human malaria species are endemic in Papua New Guinea, and are transmitted year round. This matrix of vector and parasite species produces a variable transmission landscape, which is effected by vector and parasite species distributions, vector ecology, and vector-parasite interactions. Previous studies have identified key behavioral characteristics of many vector species, including biting times, biting rates, and host indices. On-going studies are gathering similar information for vector species correctly identified using molecular techniques. However, information regarding the inherent physiological ability of these vectors to maintain and transmit Plasmodium is scarce. It is necessary to take vector competence into account in order to effectively control malaria in such a complicated vector-parasite environment. The primary aim of this study is to determine the malaria transmission potential of four common species of Anopheles in Papua New Guinea. Colony mosquitoes will be experimentally infected by feeding them with a sample of blood containing a known number of either Plasmodium falciparum or P. vivax gametocytes. The infection within the mosquito will be monitored by recording both oocyst densities in the midgut as well as sporozoite densities in the salivary glands. In addition, since mixed Plasmodium infections are common in human and mosquito populations, the secondary aim of this study is to determine the ability of An. punctulatus to maintain a mixed infection of P. falciparum and P. vivax. Colony mosquitoes will be fed a sample of blood with a mixed infection and parasite development will be monitored. In addition, the effect of an initial P. falciparum infection on subsequent P. vivax development will be measured, and vice versa.
In many malaria endemic countries around the world, the interaction of multiple vector and parasite species results in a complex transmission environment. Understanding specific vector - parasite associations within this overall dynamic is necessary for the implementation of effective integrated vector management and malaria control strategies.
|Reimer, Lisa J; Thomsen, Edward K; Koimbu, Gussy et al. (2016) Malaria transmission dynamics surrounding the first nationwide long-lasting insecticidal net distribution in Papua New Guinea. Malar J 15:25|
|Erickson, Sara M; Thomsen, Edward K; Keven, John B et al. (2013) Mosquito-parasite interactions can shape filariasis transmission dynamics and impact elimination programs. PLoS Negl Trop Dis 7:e2433|
|Keven, John B; Henry-Halldin, Cara N; Thomsen, Edward K et al. (2010) Pyrethroid susceptibility in natural populations of the Anopheles punctulatus group (Diptera: Culicidae) in Papua New Guinea. Am J Trop Med Hyg 83:1259-61|
|Mehlotra, Rajeev K; Gray, Laurie R; Blood-Zikursh, Melinda J et al. (2010) Molecular-based assay for simultaneous detection of four Plasmodium spp. and Wuchereria bancrofti infections. Am J Trop Med Hyg 82:1030-3|