The molecular epidemiology of malaria transmission in the Southwest Pacific
Project type
PhD
| Supervisor(s) | Division | |
| (Primary) | Infection and Immunity | .(JavaScript must be enabled to view this email address) |
| (Co-supervisor) | Infection and Immunity | .(JavaScript must be enabled to view this email address) |
Details of project
The recent dramatic reduction in malaria morbidity and mortality prompted a shift from control to consideration of malaria elimination. Such a re-orientation towards elimination requires a paradigm shift away from a goal of controlling the burden of disease to the actual interruption of malaria transmission itself. Achieving this will require the development of a completely new set of tools that directly target transmission based on an in-depth understanding of the processes governing malaria transmission.
While we have an increasing knowledge of the biology of P. falciparum gametocytes and at least a basic understanding of epidemiology of P. falciparum transmission in sub-Saharan Africa 1, very little is known both about the epidemiology of malaria transmission the SW Pacific in general and for P. vivax in particular.
Project goal: Determine the dynamics of malaria transmission in Solomon Islands using a combination of large epidemiological studies and novel molecular assays.
In 2012 and 2013 the Mueller and Barry labs are conducting a large cross-sectional population survey and a longitudinal cohort children 1-10 yrs. in Central Province, Solomon Islands together with colleagues from The University of Queensland and the Solomon Islands. By combining outstanding epidemiological studies with state-of-the-art molecular assays (RT-qPCR, nextGen sequencing) for detection and genotyping of P. falciparum and P. vivax gametocytes, this project aim to provide an in-depth understanding in transmission patterns.
In particular we aim to determine:
- the contribution of different age groups and asymptomatic vs. symptomatic infections to transmission of P. falciparum and P. vivax malaria in SI; and
- the relationship between the complexity of infection (mixed species / strain) and the relative gametocyte production of different strains / species.
In short, we aim to understand, who transmits malaria, where, when and how? As part of PhD project, you will therefore learn to establish high-throughput RT-qPCR assay for typing of asexual and sexual P. falciparum and P. vivax infection and apply them to the samples form the Solomon Islands studies. In addition, you will develop novel assays to detect (using RT-qPCR) and genotype (using nextGen sequencing) P. malariae and P. ovale gametocytes and apply them to samples from both Solomon Islands and Papua New Guinea.
The project will require spending time (~6-9 months) in the Solomon Islands to assist with the collection of samples in field studies and their preparation for later molecular analyses. As a molecular epidemiology project this project is best suited for a candidate with a solid background in molecular biology, who is keen to learn about epidemiology and work in population-based studies. The analyses of the data are non-trivial and will require decent numerical and computer skills and the willingness to learn about more advance statistical methods
Project references
- Bousema T and Drakeley. Plasmodium falciparum and Plasmodium vivax gametocytes – their epidemiology and infectivity and malaria control and elimination. Clinical Microbiology Reviews. 2011 2011:377-410.
- Mueller I, et al. Key gaps in the knowledge of Plasmodium vivax, a neglected human malaria parasite. Lancet Infect Dis. 2009 9:555-566.
- Alonso PL, et al. A research agenda to underpin malaria eradication. PLoS Med. 2011 8:e1000406.
- Lin E et al. Differential patterns of infection and disease with P. falciparum and P. vivax in young Papua New Guinean children. PLoS One. 2010 5:e9047.
- Michon P, et al. The risk of malarial infections and disease in Papua New Guinean children. Am J Trop Med Hyg. 2007 76:997-1008.
- Koepfli C, et al. How much remains undetected? Probability of molecular detection of human Plasmodia in the field. PLoS One. 2011 6:e19010.
- Juliano JJ, et al. Exposing malaria in-host diversity and estimating population diversity by capture-recapture using massively parallel pyrosequencing. Proc Natl Acad Sci USA. 2010 107:20138-20143.
Research interests
Despite impressive recent gains in the global fight to control malaria, the disease continues to exert a major burden to people in endemic countries. To date it is estimated that 2.4 and 2.8 million people worldwide are at risk of contracting P. falciparum and P. vivax, respectively. Our lab aims to contribute to further, sustainable gains in our fight against malaria.
We are conducting population-based malaria studies that are locally relevant for the control and eventual elimination of malaria from affected populations in the Asia-Pacific region and beyond. The population-based malaria research program of our group aims to bridge from basic Plasmodium biology to clinical development of new interventions to control and eventually eliminate malaria.
To that effect the research is focussed around three main ‘themes’:
- the comparative biology of P. falciparum and P. vivax host-parasite interactions;
- the (clinical) epidemiology and intervention research in Papua New Guinea; and
- evaluation of the impact of intensified malaria control programs on malaria burden and host-vector-parasite interaction.
Answering complex problems regarding host-vector-parasite interactions requires highly integrated, multi-disciplinary approaches. Our research program draws on diverse scientific disciplines ranging from molecular parasitology, host genetic adaptations and immune responses, clinical, epidemiological and population-based research, curative and preventative interventions to research on health systems, monitoring and evaluation, and social aspects of malaria.
A special focus lies on studying the P. vivax host-parasite interaction and our group is recognised as one of the best in studying the epidemiology of P. vivax. For further details of the project undertaken by the lab see: http://www.wehi.edu.au/faculty_members/professor_ivo_mueller
Research theme
Infectious diseases
Scientific discipline
- Microbiology
- Molecular Biology
- Statistics
Keywords
P. falciparum, P. vivax, transmission, gametocytes, molecular epidemiology, RT-PCR, nextGen sequencing, Solomon Islands, PNG