The world's scientific and social network for malaria professionals
8486 malaria professionals are enjoying the free benefits of MalariaWorld today

Exit Strategy for conquering malaria in Africa

February 13, 2013 - 12:36 -- William Jobin

What does the future hold for the fight against malaria in Africa?

If we limit ourselves to the conventional approaches to fighting malaria - drugs, bednets and biocides - the future looks bleak. It looks like an endless war. The war started about 1950 when DDT and chloroquine looked like perfect weapons. But since then the development of resistance has shown us how ephemeral they were. The mosquitoes began to eat DDT for breakfast, and the malaria parasites learned to swim in chloroquine. Historians are showing us that malaria has incredible tenacity in Africa. We long for a solution to this horrible problem - an Exit Strategy. Unfortunately WHO, USAID and the UN agencies offer us nothing but more of the same - and with declining budgets.

For the past few decades there has been an implicit but mythical Exit Strategy for the fight against malaria - the development of a vaccine. This implied weapon has been the stimulus for enormous amounts of immunological research, and has also given solace to field workers who see the disastrous brick wall of drug and biocide resistance coming again soon. The repeat of this historic disaster will mean that once again indoor spraying of biocides becomes exceedingly expensive, that treated bednets will no longer give protection, and that the current drugs will be useless. It is a grim picture, unless one has an Exit Strategy. But relying on the mythical vaccine is simply an exercise in fantasy.

Fortunately there is a practical Exit Strategy available, using proven methods that require little technology. Perhaps the lack of technology is the reason why these weapons have not been pursued by our scientific and medical elite; they are too mundane and we all want to be modern scientists. This realistic Exit Strategy features (1) shovels for digging drainage ditches and filling swampy sites of mosquito breeding, (2) window screens and (3) affordable electricity for fans that make sleeping bearable in screened houses. Unlike the current vaccines being studied, shovels, window screens and affordable electricity are durable, and do not require re-application every few years. And we already have them all over the world. Farmers all over Africa know how to drain swamps with shovels. Carpenters all over Africa know how to screen in houses, after blocking the eaves with heavy paper or papyrus. Affordable electricity is growing at the rate of 4.1% per year in Africa, as new fuel and hydropower sources are developed faster than anyplace in the world (Christian Science Monitor 2013.) It is important to note that affordable electricity is available already in many African cities. As the majority of Africans move to urban areas, they will find affordable electricity already there. Extending it to rural areas will get us to the end.

What basis is there for confidence in this practical Exit Strategy? Simply the experience in all the northern countries where physicians no longer know what malaria looks like. The historian Snowden documented the gradual disappearance of malaria from Italy after the Second World War; largely before the advent of DDT and chloroquine (Snowden 2006, and Jobin 2010). These cheap chemicals used to be thought of as the Exit Strategy in the WHO Eradication Program – until they hit the brick wall of chemical and drug resistance the first time, about 50 years ago.

Another important feature of this practical Exit Strategy is that it has multiple benefits, while a vaccine would be highly specific not only for one disease, but even for only one strain of that disease. A vaccine against Plasmodium falciparum, the most prevalent killer in Africa, would not protect against Plasmodium vivax, a common killer in most of the tropical world.

The multiple benefits of eliminating swamps and breeding sites has been shown in Tanzania to also control some other species of mosquitoes which transmit filariasis (Castro 2010). Screening of houses also keeps out houseflies which are important in transmission of cholera and other severe diarrheal diseases. Screening of houses also increases the resale value of houses, in a way that biocide spraying could never do. Buying shovels and picks to drain a swamp gives you tools to use in growing crops as well. This Exit Strategy has multiple benefits, always a winner.

What about costs of this practical Exit Strategy? It is hard to compare anything with the cost of a mythical vaccine because none exists yet, except a recent one that gives protection to only one-third of the people injected, and would probably have to be boosted every 1-3 years. The short-term impact of this vaccine almost seals its fate as an impractical tool in Africa, but in any event it would be incredibly expensive.

The cost of digging a ditch or installing screens on your house is low, especially if you do it yourself. For comparison, we would want it to be cheaper than the current chemically-based strategy of WHO and the US PMI, based on drugs, bednets and biocides. The most recent data from PMI indicate that spraying a house in Africa costs at least $7 per person protected, by a spray that was effective for about 3 months (Jobin 2012). To give year-round protection in a house with a family of 6 would cost $168 per year.

If screens were installed to last 10 years and they cost less than $1,680 they would be competitive with spraying. And this comparison neglects the cost of drugs and bednets. So screens look pretty good, especially if you do the work yourself and only have to buy the metallic screen material, some light lumber, and heavy paper to seal the eaves. Likewise if you drain the swamps and depressions around your house, you could get some pretty good picks, hoes and shovels for $1,680. This is where community efforts make the practical Exit Strategy even more feasible, as you could share these tools with your neighbors.

So I have a suggestion. Let us focus on communities in the midst of the malaria battle, and offer them an Exit Strategy that they can implement themselves. Then when WHO and the Global Fund fail, when mosquitoes learn to coexist with pyrethroids, and when ACT is no longer effective, the communities can continue the fight.

References:

Castro et al 2010 The importance of drains for the larval development of lymphatic filariasis and malaria vectors in Dar es Salaam, United Republic of Tanzania. PLoS Negl Trop Dis. 2010 May 25;4(5)

Christian Science Monitor 2013, Mike Pflanz, January 1. Boston, USA

Jobin 2010 A realistic strategy for fighting malaria in Africa, Boston Harbor Publishers, Massachusetts, USA

Jobin 2012 Improving the US Presidential Malaria Initiative, Boston Harbor Publishers, Massachusetts, USA

Snowden 2006 The conquest of malaria, Yale University Press, New Haven, USA

Average: 

Comments

Ricardo Ataide's picture
Submitted by Ricardo Ataide on

Hi Bill,

I agree that such an approach is ideal, but who would pay for it? The owners of the houses would pay for the shovels and the screens and would have to do the work? Or would the community pay, since everyone in the community will benefit? Or is it a government obligation? Would every household get a shovel, or just a few? I'm assuming it is not easy to get everyone in a community on board and it only takes one person not to let people in their lands to drain swampy water to make the entire plan crumble.

Ricardo Ataíde

William Jobin's picture
Submitted by William Jobin on

Thank you Ricardo,

...for taking my Exit Strategy one step further, to the practical realm of funding and ownership. I am working out some details based on a recent report by Chris Murray at the Institute for Health Metrics and Evaluation, entitled "Financing Global Health 2012: The End of the Golden Age?" Murray is Director of the Institute and got his funding from Gates. The funding I cite is for Development Assistance for Health, specifically for the fight against malaria in the field.

As you can see by the title, the donors are getting tired. Global funding in USD was $1.94 billion in 2009, but dropped to $1.86 billion in 2010. Murray's summarizing of the figures on funding requires his staff to do a lot of work, so he does not have accurate figures yet for 2011 and 2012. But the available Global Funds are still decreasing. It has been estimated that the funds currently available for maintaining just the current WHO strategy, and only for the African continent, were about half the amount needed (Jobin 2010 "A realistic strategy for fighting malaria in Africa", Boston Harbor Publishers, available for electronic delivery to African customers, thru Amazon.com).

The one bright spot in the picture is contributions from the US which rose to $0.5 billion in 2010, then $0.6 in 2011, and which are holding steady or rising. It appears that the new US government will continue to support the fight against malaria. However the funds coming from UN agencies and the Global Fund are showing serious decreases.

I need some more time to go over these figures and will get back to you soon. However, the general ideas I am looking at - to answer your questions - are the following:

(A) In addition to the current funding for fighting malaria in Africa, I propose that the Exit Strategy be supported by local communities and households. They will see the direct benefits, so I think they should contribute at least their own efforts and labor, This approach requires that communities be organized as part of the Exit Strategy. It is unfortunate that this community aspect has been neglected by the UN and other big donors from the North; but Sudan, South Africa and Mozambique have shown that it can be very important in giving continuity and relevance to the fight.

(B) This community effort and contribution should be in addition to the donor funding, not a replacement. So I propose that each country be responsible - within their National Malaria Control Program - for organizing the communities. If the MOH will not undertake this, then I propose that Inter-Faith groups such as the ones in Mozambique and Nigeria, be asked to organize the communities. Between the Muslims, Jews, Christians and Hindus in Mozambique they have a much better coverage on the ground than does the MOH.

(C) Regarding the donor funding from the US Presidential Malaria Initiative - the one source of funding which is stable or increasing - I propose that we ask them to allocate 10% of the spray program funding and 10% of their bednet funding, to a community based effort to get homeowners to install screens, and improve drainage. As they develop this aspect - which will gradually reduce the amount of spraying and bednets needed - I will ask them to expand it. Thus instead of spraying the same houses year after year, they will gradually be able to reduce the spraying. This will happen anyway as resistance is developing to the pyrethroids they are using. As screens are installed and mosquito breeding is reduced, the need for spraying and bednets will shrink, thus freeing the funds for the screens and drainage.

(D) One other principle I propose to get funding for local drainage and house screening is specific for countries with large natural resources coming from oil and mining. There are several of these countries - Angola being a good example - where it is clear that billions of new revenue are coming into their country, but very little of it is showing up in MOH budgets. If the US PMI simply required matching funding from Angola, this would add millions to the fight.

I would appreciate any suggestions you or others have on these principles, and in the meantime I will get to work on the budget figures from Murray's report.

Bill, with my calculator turned on

William Jobin Director of Blue Nile Associates

Jeff Juel's picture
Submitted by Jeff Juel on

Hello Bill,
I got my login to MalariaWorld working today and this is my first comment.

I am certain that you are on the right track with your postings. Traditional approaches to vector control are worthy of attention - with a twist.

Here's something to ponder: It is not the swamp or the wetland that's the problem - it's the stagnant water. What if there was a way to "fill and drain" a wetland - using water moved via the tides?

Traditional filling and draining of wetlands (with soil and ditching) destroys wetlands and is (or should be) environmentally controversial. Filling and draining them with water solves the problem without destroying the wetland and harming the flora and fauna that rely on them.

As long as the high water level in the wetland is the same on every tide, the filling and draining will dilute the mosquito eggs and larvae to zero. (I call this "monotonous high tides".)

What I have in mind could be used for marshes and wetlands that lie at or near Mean Higher High Water, situated behind dikes/levees near coastlines and along the lower reaches of rivers that are under tidal influence. This applies to a surprising large fraction of the world that is inhabited by humans.

The water in the canals and channels of the wetland would rise and fall with the tides - with brief periods of stagnant water before and after each filling. Egg laden mosquitoes might be fooled into depositing their eggs when the water is stagnant. The larvae would ultimately be diluted to oblivion.

Advocates for wildlife that rely on vital wetland habitats might provide funding for this.

Constructing the levees and drainage infrastructure that this scheme utilizes would save lives and provide flood control benefits while thwarting the breeding of floodwater mosquitoes.

Simple modifications to the drainage infrastructure associated with an existing flood control project could be done for a nominal cost.

The device that produces monotonous high tides is fail-safe; it operates unattended for years; and it requires no power - the flow of water makes the device open and close.

I hope that you will read a document that I composed describing my ideas in detail --> http://www.issuu.com/jueltidegates/docs/a_new_weapon_in_the_war_against_malaria_or_an_insi

I welcome your suggestions and any comments.

Jeff Juel, PE

Jeff Juel, PE
www.jueltide.com