A panoramic photograph of Malham Cove in North Yorkshire.

kegglogoMalaria

If you came to my talk, thanks for coming and here are the list of items I said I'd show you. Even if you didn't come then this page shows you some of the things I talked about.

Malaria the disease

 "Malaria has probably killed more human beings than any other single disease". - Livingstone, 1971

For as long as there have been humans there has been malaria. Slavery in Africa, the fall of the Roman Empire and the rise of Mussolini in Italy are all closely tied to this disease with whole books written on the topic.

In the modern world, we are particularly interested in Malaria because it is so good at killing us but also because it is such a debilitating and isolating disease. Our best estimate is that malaria costs a country about 1.3 percentage ponts of growth per year. As the late Andrew Spielman put it in the best video on strategies for fighting malaria you can watch,

"Malaria is like no other disease, it isolates communities, people simply don’t go there. It violates Adam Smith’s precept of freedom of movement as being essential for economic growth. It sits on the people. It protects them from intruders but also denies them access to the world economy. I think that’s probably the most important element of economic growth in Africa…"

A false dawn in controlling malaria

Quinine was known in Europe since the Spanish were given it by natives of Peru and Bolivia in the 17th Century. It remained effective until over-use in the 20th Century led to resistance developing. Quinine is an interesting chemical because it fluoresces blue under ultraviolet light, try it if you're in a nightclub and get a Gin & Tonic. If that seems a bit nasty, then you're not wrong. Quinine is a horrible drug and if it wasn't found in nature there's no way we'd let even tiny amounts be put in Tonic Water.

Given the side-effects of quinine, and malaria's increasing resistance to it, the US Army, amongst others, started large programmes to find new alternatives and created lots of drugs which were much more effective and with fewer side-effects. Chloroquine was popularised after the second World War and further urgent research was carried out during the Vietnam War where it was reported that more soldiers were incapacited due to malaria than due to enemy fire.

By far the biggest step forward in controlling and eradicating malaria came with the discovery and widespread use of DDT. This chemical seems almost completely harmless to birds and mammals but kills insects dead on contact, stays active on walls for long periods and is extremely cheap to produce and spray. Widespread spraying to kill mosquitoes and the distribution of cheap anit-malarials reduced malaria deaths worldwide to extremely low levels. Harvard Medical school stopped teaching students about malaria, and experts thought the disease would be eradicated like Polio and Smallpox within five years.

The reality, as reported in New Scientist, was far more depressing. The excellent Silent Spring by Rachel Carson made the world aware that DDT was weakening the shells of birds across the globe and its use was severely restricted. Governments saw that malaria was no longer a large problem in many countries and didn't continue with the expensive programmes. which would be needed to achieve eradication. Malaria came back to communities that had lost their immunity, and killed more than ever before. Undergraduates learn about Malaria at all medical schools again.

 

Malaria the microorganism

The best way to learn all the details about malaria is to listen to the excellent free podcasts at This Week in Paratism.

There are a lot of reasons why it's difficult to study malaria. Firstly it wasn't until 1972 that we figured out how to grow it in a lab so there wasn't much chance to study until then. Even now, it's time-consuming and temperamental making experiments very hard. Furthermore, it's genome is extremely strange. DNA is made up of four molecules which we give the letters C, G, A and T. In most organisms there are about equal numbers of all four but in Plasmodium falciparum (that's the severe malaria we study) ninety p percent of the DNA is C or G. That makes a lot of genetic manipulations really difficult to do.

 

Recent progress

Thanks in large part to money and talent from the Bill & Melinda Gates Foundation, Glaxo Smith-Kline, the WHO, UNICEF, UNDP, The World Bank and many others... we are starting to roll back malaria. Deaths have fallen in all of the last ten years, at an increasing rate and are now down 20% in a decade.

China's project 523 setup by Mao in the late 1960s has provided with an incredibly powerful new drug with which to fight malaria and as long as we avoid resistance by strictly adhering to combination treatments we may have time overcome to parasite in much of the world.

What now

The money that the Bill & Melinda Gates foundation have dedicated to malaria research and eradication is already making a different, both on the ground in Africa and in basic science at places like the Liverpool School of Tropical Medicine.

Money is still a problem though. Public funding of science has been falling since the cold war, with the UK following a similar trend to the USA. As described excellently by Brian Cox, we spent a tiny proportion of our wealth on science despite the benefits it brings. Private funding of science has not produced the same breakthroughs as public funded, and thus publicly shared, science. The worrying truth is that we've already solved the easy problems; we can't expect to solve the hard problems left behind without continued focus.