Friday, February 2, 2018

Gates vs. Malaria: How Bill Gates aims to win the fight of his life

Devex
By Raj Kumar

Devex Founding President and Editor-in-Chief Raj Kumar with Bill Gates at the World Economic Forum in Davos.

DAVOS, Switzerland — Bill Gates animated, gesticulating, stops himself mid-sentence. “This is way more than even you guys may want to know,” he says.

He’s speaking with Devex at the World Economic Forum’s annual meeting here, talking about the science and technology behind the push to eradicate malaria parasites — one of Gates’ favorite subjects and one which he has elevated at this meeting two years in a row.

When thinking about systemic challenges like a persistent infectious disease that’s been killing homo sapiens since we first evolved, most people find comfort in focus: It’s about bed nets or new drugs or a vaccine.

Gates is not interested in a silver bullet, a single tool. “Malaria is a very complex disease and understanding the etiology and the resistance, and do you do mass test and treat, do you do MDA [mass drug administration],” he begins. He basks in the complexity of the disease itself — how the various species of plasmodia morph and change and evade easy elimination — and the multifaceted way it must be fought. “Basically we’re trying to get rid of the human reservoir,” he says, before launching into an extended analysis of why that’s no small feat.

The first major push to eradicate malaria from the earth — a hubristic failure — was set in motion in 1955, the year Gates was born. If he gets his way, and malaria is ultimately eradicated by his planning target of 2040, he will be 85 years old. That the fight could take Gates’ entire lifetime is a marker for just how tough this so-called “zero goal” will be to reach.

It will take, Gates tells Devex, an unwavering focus on case management in the most endemic countries, particularly those of Central Africa. Fifteen countries, all but one in sub-Saharan Africa, carry 80 percent of the global malaria burden. There, eliminating all malaria is many years off and the best that can be done for now is to “shrink the map,” reducing the geography where malaria is rampant.

In some countries, including those of Central America and the Dominican Republic where relatively few cases remain — just over 40,000 last year across the region, a tiny fraction of the 216 million cases worldwide — elimination of the disease is a near-term possibility, with sustained financial commitments, including the one Gates announced just before our interview.

Those financial commitments are not assured. There is a long history of countries — including Sri Lanka, India, Swaziland, and Zanzibar — getting close to eliminating the disease only to see it come roaring back when government and donor funds were shifted to seemingly more urgent issues. Last year’s World Malaria Report by the World Health Organization showed 24 countries with a significant malaria burden seeing signs of resurgence.

But scaling up today’s approach, diagnosing and treating patients suffering from the symptoms of malaria, and distributing bed nets to others, isn’t going to be enough on its own to reach global eradication. “We’re going to have to invent new tools,” he says.

“We will have good drugs,” Gates is confident, including some that will require just a single dose and that can clear out the cells that lurk in human blood and transfer the disease to mosquitoes when they bite. Those gametocytes are particularly challenging to address because they don’t cause symptoms, so people don’t know they are a walking reservoir for the disease.

And “we will certainly keep the bed net insecticides” and indoor spraying including new compounds since some mosquitoes have developed resistance to the existing ones.

But Gates knows even these advances likely won’t be enough against a parasite that morphs through several stages during its life cycle and has evolved over many millennia to survive.

He’s looking to new ways to control the mosquito population, like the genetic engineering technique "gene drive" that could one day alter mosquitos so they can’t carry the malaria parasite or so that certain malaria-carrying species can’t reproduce and die off.

And he seemed energized by the thought of another vector control device, one that others with less patience might have already written off: An improbable laser beam device made famous by a video showing it shooting off the wings of individual mosquitos. Developed with his friend and collaborator Nathan Myhrvold at Intellectual Ventures, the “Photonic Fence” has been a decade in the making but is “still not ready for prime time.”

Gates — whose own money has funded this endeavor — is not deterred. “The test results [from a trial this past summer in Florida orange groves] have come back fairly positive, now they’re going to do some more tests, they’re going to try a bunch of different insects, they have to prove out the safety — that’s been more challenging than we expected,” he said.

Will better drugs, insecticides, and new ways to kill off mosquitos be enough? “Probably not,” especially in the countries where “the biting rate — the EIR [entomologic inoculation rate] — is like 100 bites a year.” That is, unless there was a “very powerful vector control tool where you could knock down the mosquito population, say, three seasons in a row by maybe a factor of 40.”

All of which is to say that vaccine development for malaria remains very much on Gates’s agenda. The current vaccine candidate, RTS,S, was funded by the Bill & Melinda Gates Foundation and has a “very modest duration” — its efficacy is diminished after a year and it requires four doses— “so whether that in its current form is a tool that you would put money into relative to bed nets and other things — that’s still unclear,” he said. WHO is currently engaged in a large scale pilot of the vaccine in Kenya, Ghana, and Malawi.

Another critical tool, according to Gates, is a “serology diagnostic,” a kind of “super sensitive diagnostic” that “has a long time tail” so even people who show no symptoms can be identified “to see if there’s been any malaria in an area”.

Like the parasites he’s chasing, Gates, the former hard-charging technology executive known for having little patience and not suffering fools, seems himself to have evolved. “There are still people in the field who think the eradication is not an achievable thing and that’s fine,” he said calmly. That’s a stark admission given his foundation is funding every aspect of this effort, from gene drive technologies to drug and vaccine development to bed nets and spraying, as well as so many other global health and development initiatives made more challenging because of malaria.

And even the most influential philanthropist in human history knows he can’t achieve this alone. Gates is hoping “to bring China in as a very big donor” and “Australia as a regional donor.” And he declares himself “pretty hopeful” with the United Kingdom and Germany reaching the 0.7 percent of gross domestic product aid target, and the United States Congress “maintaining these priorities.”

If this scourge on humanity does leave this earth once and for all, perhaps in the twilight of Gates’ own life, it will have been in large measure because of decades of persistence on his part. All those years of strategizing, operationalizing, and pushing the world to believe this can be done will have paid off. But there’s a long way to go yet.

“Although malaria deaths have come down … we don’t have the knock-out tool in our hands. So people’s faith and patience and belief that we can maintain this as a priority partly requires faith as well as knowing the numbers,” he concluded.

No comments: