The greatest impact upon the spread of malaria are economic activities and efforts to control the disease. While DDT finally eradicated malaria from Europe the disease had already been declining since the late 19th century. As Europe became wealthy and more developed, so the incidence of malaria declined. As the area of land under agricultural production increased, so the number of mosquito breeding pools declined. Improvements in technology meant fewer workers were required resulting in increased urban populations and reduced rural populations and the probability that the disease would spread was reduced. As people began to own more livestock mosquitoes had a greater number of potential animals upon which to feed reducing the spread still further. In addition, improved housing separated farmers from livestock and provided better protection from mosquitoes. Malaria is now a disease of the poor. Have you ever visited a country that still has malaria?

My wife and I visited Tunisia in 1972, a country that had malarial mosquitoes even though we didn't know it at the time. This was our first introduction to mosquitoes and they seemed to like British blood (why wouldn't they) and the hotel upon a request would spray your room while you were having a meal in the dining room. The spray was very effective considering that the windows didn't have fly screens. The spray was DDT, a product that has been banned worldwide because of its impact on bird populations. DDT was cheap and very effective. Nothing has been produced to replace it that is also affordable. The impact on wildlife has since been proven to be less serious than originally thought and with climate change an effective spray is even more needed than before. Should the ban on DDT be rescinded?

There are persistent reports that China continues to produce and distribute DDT even though it signed the accord that banned it. It also has been accused of exporting DDT to 3rd world countries. Given how effective DDT is (when combined with the use of netting, standing water maintenance and other controls on larva) perhaps China should admit it produces DDT and share it more openly with the countries that need it.

South Africa recently experienced a malaria epidemic after they removed the use of DDT and malaria returned after an absence of around 40 years. DDT was reintroduced and the result of was an 80% reduction in cases. The success of malaria was clearly more dependent on vector control than on rainfall. Malaria is a major determinant of poverty. Protocols that aim to limit CO2 emissions and economic growth, will not materially affect the spread of infectious diseases but will hamper the abilities of poor countries to cope with health crises. Man's activities have a far greater impact on the spread of malaria than climate, and more than the part that man's emissions may be playing in changing the climate. If we want to see successes in malaria control, reducing the levels of government bureaucracy is paramount. As in Europe and North America, the long run control of malaria and other infectious diseases depends on the ability of people to increase their wealth and prosperity. However, this will be hampered by attempts to reduce greenhouse gas emissions and through proposed reliance on expensive and inefficient 'renewable' energy. As Bill Gates and others have discovered and are investing in, cheap energy from the likes of fusion nuclear technology is the key to prosperity in 3rd world countries and prosperity leads to better control of malaria. Should our focus be on wealth creation or climate change?