About 100 years ago Dr Ronald Ross, a distinguished medical officer in the British Empire's military medical service in India, demonstrated for the first time the critical part played by Anopheles mosquitoes in the transmission of malaria to humans. Born in India and medically educated in St Bartholomew's Hospital in London, he was subsequently awarded the Nobel Prize for his seminal work in identifying the life cycle of the malarial parasite in its mosquito host and the source of what had until that time been thought to be some kind of miasma which inflicted cyclical and often fatal fevers in those people who lived in marshy and moist areas of the world.
It was not unreasonable to suppose that, once the life cycle of the Plasmodium parasite which causes malaria had been identified and its means of transmission to humans demonstrated, further scientific medical developments might have led to eradication of the disease in humans. Indeed, for many decades great strides were made towards just that desirable objective.
More effective drugs were developed to combat the disease and insecticide programmes to fight the mosquitoes were extended. A global eradication programme was announced by the World Health Organisation in 1955 and, within a decade, malaria had been either eradicated or significantly reduced in nearly 50 countries. It looked as if the battle would be won. But, even as the most lethal of the four malaria parasites was becoming immune to the drugs, and as significant numbers of Anopheles mosquitoes were becoming immune to the effects of DDT and DDT itself was becoming unpopular as an insecticide, so malaria began to spread again.
Where the WHO had reckoned that maybe fewer than four million people might be afflicted by malaria in the 1980s, the real figure turned out to be more than 10 times that. Now somewhere between one and three million people die of malaria each year, many of them children under the age of five years. Between two and three billion are still at risk and every year about 500 million people fall victim to the Plasmodium parasite. It may not be insignificant that, in terms of the people afflicted, the vast majority live in equatorial developing countries, even if increasing numbers of tourists and business people from northern European and American nations are finding malaria increasingly difficult to avoid. And the currently best mechanism of malaria avoidance - an insecticide-impregnated mosquito net over everyone's bed - is unlikely to have major preventive effects in countries where many have no houses, never mind beds or mosquito nets.
Meanwhile, the equatorial developing countries find it increasingly difficult to develop. Poverty, overpopulation, urbanisation and other factors make it difficult enough without the scourge of malaria further sapping human energy and medical resources. It is very much to be hoped that last week's international conference of experts in Hyderabad noted the disparity of imperatives between the rich and the impoverished countries of this globe. It is more fervently to be hoped that those of us who are both better off and less immediately threatened by the devastation of malaria will do a great deal more to combat effectively the life-sapping scourge of malaria that is being suffered by our less affluent equatorial brothers and sisters.