vivaxGEN: A global collaboration using translational genomics to develop new molecular surveillance tools to support the elimination of P. vivax
Aim:

To develop novel molecular surveillance tools that provide clinically relevant information on emerging parasite adaptations, transmission dynamics, the major routes of parasite spread within and across borders, and the impact of local treatment policies on the dormant liver-stage reservoir.

The problem – limitations of traditional surveillance tools:

In the Asia-Pacific, Horn of Africa and Americas, Plasmodium vivax is now the predominant cause of malaria, affecting the world’s poorest and most vulnerable communities. Efforts to contain P. vivax have been constrained by the parasite’s ability to adapt and form dormant liver stages that can relapse months after inoculation. Traditional malaria surveillance focuses on measuring the prevalence or incidence of infection, essentially counting clinical cases. Whilst this is useful for monitoring transmission reduction, it does not inform on a dynamic parasite population that may be adapting to public health interventions. New surveillance tools have potential to provide far greater insights into the parasite reservoirs, and how they are adapting and spreading within and across national borders.

Our strategy to develop and implement new molecular surveillance tools:

Our research program incorporates molecular biology, population genetics and genomics, and software development to inform on the biology of P. vivax. To assimilate these data, we are developing laboratory and online analytical tools for molecular surveillance. Our strategy employs a 4-step plan:

  1. Genomic analyses of a growing global collection of P. vivax infections to identify subsets of markers (barcodes) that can inform on local transmission patterns, parasite spread within and across borders, imported infections and their origins, drug resistance and other forms of parasite adaptation.
  2. Laboratory-based assays to generate these P. vivax barcode markers to support cost-effective high throughput genotyping of representative host and parasite population.
  3. Bioinformatics tools to support local researchers, control programs and other key stakeholders to effectively analyse and interpret the parasite genotyping data.
  4. In country capacity building to ensure effective translation of molecular surveillance tools and generate locally informative data in a timely manner. The program currently comprises partners from 16 countries, that have collectively contributed a global collection of >1,000 P. vivax genomes and >6,000 patient samples from cross-sectional surveys as well as unique longitudinal cohorts with up to one year follow up.

In the next five years, specific objectives of the program are to:

  1. Expand the global repository of P. vivax genomes and generate new knowledge on emerging molecular adaptations, including evolving drug resistance
  2. Transfer our earlier microsatellite-based tools into higher-throughput SNP methodologies
  3. Expand on earlier tools for mapping imported infections by developing higher resolution tools to track P. vivax spread within-country and across border regions
  4. Develop molecular tools to track relapses that can inform on the efficacy and adherence of local treatment policies to minimize the liver-stage reservoir
  5. Implement the molecular surveillance tools in a range of endemic settings at sites in Bhutan, China, Indonesia, Malaysia and Vietnam.
Implications for policy and practice:

This program will provide researchers and malaria control programs in endemic countries with actionable knowledge, supporting the rapid containment and elimination of P. vivax.

For further information:

Contact Associate Professor Sarah Auburn via email.