Bill Gates vs. the mosquitoes, who's winning?

Oct 16, 2011

Four years ago the Bill & Melinda Gates Foundation called for the eradication of malaria. Since then it has spent nearly $2 billion in the effort.

While there has been success, many still wonder: What factors are driving malaria away? What's causing the success? There are also many confounding factors at play ranging from climate change to the mysterious disappearance of mosquitoes in east Africa.

This week the foundation hosts a summit for the world’s malaria experts to map out the next steps.

On the front lines

Fighting malaria is a centerpiece of the foundation's strategy to save lives around the world, and they have helped deploy a dizzying array of weaponry in this battle.

The war against malaria – and the pesky mosquitoes that carry it – calls for every weapon you can imagine. The global strategy coordinated by organizations such as Roll Back Malaria, and the Gates Foundation’s approach, has relied on these three big guns:

  • Bed-nets, treated with insecticides, to prevent mosquitoes from biting people at night,
  • spraying insecticides in homes,
  • expanding the drugs used for treatment of people once they're infected with malaria.

Those are the mundane approaches. Then there's the high-tech (and unusual):

  • A vaccine (top of everyone's list), that would protect everyone who lives in or visits a malaria zone;
  • Nathan Myrhvold (Microsoft's former technology wizard) is working on a laser zapping machine to get mosquitoes; and
  • various scientists are working on genetically modifying mosquitoes, so they can't reproduce or spread the disease.

None of these is ready for prime-time. The best vaccine candidates so far are only half-way effective.

Fewer deaths, but do we know why?

Video of a malaria parasite inside a red blood cell:

Still, there's certainly been progress when it comes to saving lives. Ten traditionally malaria-infested countries (mostly in Asia) should eliminate malaria deaths by 2015, says David Brandling-Bennet, chief of malaria programs at the Gates Foundation:

"We are making progress, especially toward getting better control of malaria around the world, including in Africa. And this is first time we have seen high-level control of malaria in a number of African countries," he says.

The question remains, What factors are driving malaria away? What's causing the success?

As Tom writes on the Humanosphere blog, nobody can say for sure what's making the biggest difference:

Part of the problem with estimating success in combating malaria comes from the difficulty in accurately identifying the disease burden.

Malaria is often not diagnosed or misdiagnosed, especially in poor countries, because its symptoms are somewhat generic – fever, fatigue — and most of its fatal victims are children in poor communities where health services, let alone data collection, are poor or non-existent.

Factors include: the the bed-nets, insecticides, and medications mentioned above.  But there's also a natural cycle to malaria, climate change, and the strange disappearance of mosquitoes in east Africa (it appears nobody knows why they're disappearing).

The malaria life cycle in man and mosquito:

Of course we want to get rid of malaria -- don't we?

This is an odd part of the discussion. Malaria was eliminated from the United States and many other countries, long ago. But, Tom notes, the goal of "eradicating" malaria from Earth is actually controversial.

The problem ... isn’t the sentiment. Everyone would like to see malaria go the way of smallpox. The problem is that if eradication fails, again, many are concerned the more modest but life-saving efforts aimed at controlling the disease will be abandoned, again.

One reason is that so many of the most malaria-infested countries (in sub-Saharan Africa) have poor health systems, in general. Those shortcomings have undermined many previous malaria efforts. The parasite might seem to be gone, but if it's persisting at low levels, then it tends to flare up again when the world moves on to other problems.

So, it's a noble goal to declare "we will eradicate malaria," but people might potentially be better off with a campaign that says "we will keep malaria under control."