Seeking new momentum in malaria fight

Experts, program heads, and present and future leaders in the fight against malaria gathered at Harvard Business School in June for a weeklong workshop aimed at supporting global eradication efforts.

The program is an annual event that rotates among locations chosen by the three host organizations: Harvard University, the Barcelona Institute for Global Health at the University of Barcelona, and the Swiss Tropical and Public Health Institute at the University of Basel.

While the number of malaria cases has fallen in recent years, experts say a renewed effort and new tools are needed if progress is to be maintained. Pedro Alonso, director of the Global Malaria Programme at the World Health Organization (WHO), and Dyann Wirth, Richard Pearson Strong Professor and chair of the Harvard Chan School’s Department of Immunology and Infectious Diseases and a board member of Harvard’s Defeating Malaria: From the Genes to the Globe initiative, sat down with the Gazette to talk about the challenging goal of relegating malaria, like smallpox, to the past.

Q&A

Pedro Alonso and Dyann Wirth

GAZETTE: Tell me about the leadership event. Why is it important in the effort to rid the world of malaria?

ALONSO: The event is a leadership course on malaria and malaria eradication. This was something that Dyann and Professor [Marcel] Tanner from Switzerland and myself thought of a number of years back. At the time, the world had been doing really well in the fight against malaria and the concept of eradication, which means doing away completely with the parasite from the face of the planet, was back on the table.

Looking back on the first attempt to eradicate malaria, in the 1950s, there were a number of lessons to be captured, but I believe two important ones. One, research was abandoned during that first eradication campaign. There was this notion that we had the tools and the knowledge, and there was no need for further research. That was a fatal mistake that we didn’t want to make again.

The second is that it is often said that the first malaria eradication campaign failed to eradicate malaria but nearly succeeded in eradicating research and malariologists. Therefore, the other key driver was the notion that you do need — even when you are making good progress — to build a very strong foundation of well-trained leaders who will be able to drive this process in the years to come.

GAZETTE: How ambitious is the goal of eradication?

ALONSO: It is a tough job and it’s going to take us a long time to do it. As to the question: Will there be eradication? The answer is yes. But we now need to discuss when and how we are going to achieve it. We have all of the right tools in place, but do we have all the human resources and technical capacity in place?

WIRTH: In some ways we’ve captured the low-hanging fruit. Doing better implementation of what we already have has caused a dramatic decline. In some countries, malaria cases went down by 75 percent. And overall reduction is somewhere in the 40 to 50 percent range.

“The World Malaria Report from the WHO said malaria is at a crossroads. Now’s the time when we need to really dig in and try to understand why progress slowed.”

Dyann Wirth

GAZETTE: You mentioned low-hanging fruit. Are we talking about simple things, easy to deploy, like bed nets?

WIRTH: Yes. Long-lasting-insecticide-treated bed nets, residual insecticide spraying, and diagnosis and treatment at scale with effective drugs. Those are the pillars of what has worked, but now progress has slowed. Overall progress is great, but the [change] over the last couple of years has not been so great.

The World Malaria Report from the WHO said malaria is at a crossroads. Now’s the time when we need to really dig in and try to understand why progress slowed. And — Pedro and I share this belief — we are going to need new tools.

The ideal would be a long-lasting, very effective vaccine. That’s the kind of thinking we need now, because to develop a vaccine starting now is a decade-long process.

That’s just an example. Perhaps we could genetically engineer mosquitoes to change their ability to transmit [the malaria parasite], or to reproduce. But questions remain about whether it will work and whether that’s the right strategy.

GAZETTE: Who attends the workshop?

WIRTH: We try to get as broad a range of participants as possible. We have people coming from leading research institutions, heads of national malaria control programs, heads of agencies or programs that identify need for products and develop products, people from major philanthropic organizations, the major funders, and we have people from multilaterals like the Global Fund to Fight AIDS, Tuberculosis, and Malaria …

ALONSO: From the U.S. government, the President’s Malaria Initiative, Centers for Disease Control and Prevention, National Institutes of Health …

WIRTH: And we have people from the WHO’s Global Malaria Programme and Pan American Health Organization who are positioned in regional centers where they act as resource people for country programs.

ALONSO: We at times struggle with calling this a course, because what it becomes is a joint dialogue and discussion. So it has the format of a course, but it takes just a couple of minutes before that person is questioned by the participants. It really brings people together with very different backgrounds, from across the world, and one of its strengths is this element of networking.

You put into the room someone from the Jiangsu Institute of Parasitic Diseases in China, which has just reached zero cases for the first time in the last 3,000 years — has stopped malaria — with someone from Senegal, which is still struggling with a fair amount of malaria, or from Tanzania. That cross-fertilization, putting people in the same room for a week with the best facilitators in each discipline — it’s a wonderful experience and one that leaves a deep impression on them.

GAZETTE: We talk about challenges, but there are quite a few countries where malaria has been eliminated. It used to be here in the U.S. and I’m interested in the China example. What has been the decline in cases worldwide over the last 10 years?

ALONSO: In the early part of last century, there were still major outbreaks of malaria here in Boston, and there were big ones in Washington, D.C. Malaria was only eliminated in the 1960s from the U.S.

Probably most of the planet had malaria transmission 150 years ago. So countries have been eliminating malaria. That has been through a combination of economic and social development and a very targeted plan of public health action.

So there’s been great progress in many parts of the world, and a certain sense that probably the easier ones are the ones that have eliminated malaria through a combination of economic development and the fact that efficiency of mosquitoes varies from some parts to others. Where it has been eliminated, probably the mosquito was not the most efficient at transmitting malaria.

We are starting to see some of the harder countries managing to cross the finish line. Perhaps the most remarkable example is Sri Lanka, which is an island country but a very tropical one, with pretty good mosquitoes. And they managed to eliminate and be certified.

China managing to do this is really a major [milestone]. China was a highly endemic country and last year they, for the first time in history, reached zero cases. That needs to be confirmed over the next couple of years, three years, before they can be certified.

In terms of absolute numbers, we are now somewhere around 220 million cases, which is down from something like 250 million or 260 million. If you say that’s not a lot, remember we’ve had huge population growth in that time. So, in terms of rates, you’re actually talking about a 40 percent reduction in cases and a 65 to 67 percent reduction in deaths.

GAZETTE: What has been the key for the countries that have been successful?

ALONSO: Political commitment. It’s a rather loose term, but you can point to that and say that is what it is.

Last week we certified Paraguay, which people may think an unlikely country to be malaria-free. But Paraguay has a 35-year history of aiming to eliminate malaria, across very different governments and political situations.

Sri Lanka actually eliminated malaria in the face of significant civil strife. They made up their mind as a country and said we’ll fight each other — rather viciously — on many other things, but the one thing that we agree on is that we’re going to get rid of malaria.

WIRTH: The other piece — in the countries that have eliminated — is that they’ve had the right combination of professional staff supported by universities. In Sri Lanka, there was this integration between the people doing the elimination and the knowledge base and research base that told them how to do it and kept up with it. I actually think that is underemphasized. In the end, each country has to solve its own specific problem. There can be standard operating procedures but they have to be adapted with local knowledge.

GAZETTE: Where are there gaps in research?

WIRTH: I think we need to understand how the parasite evolves and is selected.

The parasite is a survivor, as is the mosquito. The survival tactics include resistance to drugs and insecticide, so we need to understand that and be able to use that to our advantage. I think we need a way of preventing disease and preventing transmission that’s more broad-based, and without a vaccine that’s going to be difficult. The alternative to that is really a change in the mosquito biology. Either you reduce the number of mosquitoes that can transmit disease or keep the mosquito population extant but populate it with mosquitoes that can’t transmit the disease. There are various ways of thinking about that, but those are tools that are really missing.

This interview was edited for length and clarity.