Getting to Zero: Why We Need Systems Thinking to End Malaria

Happy World Malaria Day, everyone. I want to share thoughts from a recent speech I gave at the Institute for Systems Biology on what it will take to end malaria for good.

In talking about the Bill & Melinda Gates Foundation’s vision for a malaria-free world, I’m often asked: Is malaria really that complicated? Don’t we have good treatments? Aren’t bed nets pretty effective? The short answer is, yes, we do have many powerful tools to fight malaria. Unfortunately, they aren’t enough if our goal is to create a malaria-free world where no child is vulnerable to suffering and death caused by a simple mosquito bite.

Despite major progress against malaria in the past decade and a half, billions of people worldwide remain at risk of the disease. It claims the lives of 400,000 to 500,000 people annually, most of whom are children under 5. But even in the face of these challenges, I’m encouraged by the tremendous progress we’re making in identifying innovative tools and strategies to end transmission and accelerate elimination.

Earlier this month, I spoke in Seattle at the Institute for Systems Biology’s (ISB) 16th Annual International Symposium. ISB takes an interdisciplinary and multi-sector approach to the health sciences, which was reflected in an audience that included representatives from universities, nonprofits and corporations. ISB promotes strategic partnerships across areas of expertise — exactly the type of cooperation needed to fight global diseases like malaria and transform the collective health of individuals, communities and the environment.

Beyond cooperation, however, we desperately need new tools to fight malaria. And I firmly believe that systems biology, with its focus on advanced informatics and mathematical modeling, is one of the most promising approaches for rationally combining old and new tools. Defeating malaria demands that we understand the complex biological system that perpetuates cycles of infection and reinfection, and systems biology can produce realistic simulations that lead to smarter, customized sets of interventions in the field.

I talked about how systems biology applications have already yielded more effective solutions. For instance, a combination of surveillance, GPS mapping, cell phone data records, and remote sensing is helping us integrate the data coming from individual field studies by giving us insight into human mobility patterns and localized variations in climate and geography. We’re even learning more about the biting behaviors of mosquitoes.

This multi-factor approach to data analysis generates new insights and strengthens our ability to identify the appropriate combination of interventions — such as the focal drug treatment of a village combined with bednet distribution and household insecticide spraying — all required to achieve elimination in certain regions. Further, this example illustrates a core utility of systems biology — identifying combination interventions with greater impact than the sum of their parts.

But how do we get to zero cases of malaria? It’s a tall order, as we’ve seen in those parts of the world with low levels of transmission such as Cambodia where plasmodia tenaciously hang on. While diagnosing and curing a single case of malaria is a relatively straightforward task, eliminating malaria from an entire community or nation can be an incredibly complex undertaking.

The malaria parasite is a marvel of evolution, capable of rapid adaptation and able to co-opt the biology of humans and mosquitoes to ensure its survival. The same is true of the mosquitoes that transmit these parasites to people. Human behavior can be incredibly hard to predict, almost as hard as predicting the weather. But by collecting and intelligently integrating data on these variables, we can build more robust models and design interventions that can outsmart an ancient foe.

While malaria has benefitted from increased resources and commitment over the past decade, the next chapter of the fight requires us to be more efficient and targeted with the resources we have. Analyzing data based on what we have learned will help us direct resources where they can have the most impact. We also face the threat of drug and insecticide resistance. That means the more targeted we can be in our actions, the longer those tools will work. That’s where the data and integration meet reality.

Much work remains. But as I reminded the audience at ISB: consider what we’ve achieved so far with comparatively limited tools and data. Our job now is to sustain this positive momentum and drive toward new opportunities. I am especially encouraged by the fact that the lessons we learn from applying systems biology to malaria are also strengthening the fight against other global diseases such as tuberculosis and HIV. With this powerful approach, grounded in data and empowered by technology, I am confident we can devise fresh ways to rid our world of malaria and ensure all people have the opportunity to lead healthy, productive lives.