vivaxGEN: Molecular surveillance of P. vivax

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.

Method: 4-step plan 

1. Genomic analsyses
2. Lab-based assays
3. Bioinformatics
4. Capacity-building

Outcomes

• Online interactive platform for sharing and analysing Pv genotyping data
• Online tool to determine a parasites origin of infection
• SOPs for defining parasite relatedness and discrimination of reinfection, recudescence and reinfection
• Geospatial mapping of Chloroquine resistance

Project details

Capacity Building
Drug Resistance
Genetics and Genomics
Indigenous Cases & Importation
Measurement of Transmission
P. vivax
Surveillance

Jan 2011

Afghanistan
Bhutan
Cambodia
China
Colombia
Ethiopia
Indonesia
Iran
Malaysia
Nepal
Pakistan
Solomon Islands
South Korea
Sudan
Thailand
Vanuatu
Vietnam

Genetic Epidemiology
Malaria Molecular Surveillance (MMS)