So what is malaria and why do we get so concerned about it? After all, it's only caused by a bite from a bug!
That bug, of course, is a mosquito which, when it bites, feeds on your blood and in doing so can transmit disease from person to person. Whilst it is very difficult to estimate numbers, roughly speaking it is thought that as many as 750,000 human deaths per annum are caused by mosquitoes making it the most deadly creature on earth. Some of those deaths are caused by Dengue fever but over half the total number of deaths is caused by malaria. This makes them almost as dangerous to men as men themselves!
It is likely that malaria has affected human beings throughout our evolution but as far as we can see, the first reports documented of a disease with symptoms matching those of malaria date back to the ancient Egyptians in around 1550 B.C. and then by the ancient Greeks in about 413 B.C.
Even the early documentation included reference to the apparent connection between the disease and damp, swampy areas; the word malaria has its derivation in Italian and literally means ‘bad air’. It was believed that the disease was caused by the damp, stagnant air itself and no other connection was considered until the discovery of the parasite
A French army doctor named Charles Louis Alphonse Laveran authored a treatise on military medicine in which he challenged the then held belief that malaria was restricted to low lying, humid areas; he had noted that malaria could also occur in temperate areas and also that not all tropical areas had the disease. Whilst malaria had been associated with the ‘bad air’ of the humid, swampy regions, contemporary articles were now suggesting that other diseases associated with such things were actually caused by microbes.
Laveran continued his research into this and in 1880 he described the malarial parasite and proposed that it was the actual cause of malaria. The ultimate piece of the puzzle was put in place by Sir Ronald Ross, a British physician who, whilst working in India in 1897 observed the development of oocysts on mosquitoes that had fed on infected humans. This description of the complete life cycle of the malaria spreading mosquito led to him being awarded the Nobel Prize for Medicine in 1902.
Malaria is a deadly disease which is called by a single cell parasite genus known as Plasmodium. There are four types of the Plasmodium genus that cause the disease, P. falciparum, P. malariae, P. ovale and P. vivax and it is spread by female anopheline mosquitoes.
The disease symptoms include fever, chills, headache, vomiting and other symptoms similar to those experienced in a case of severe flu; if the malaria infection is severe it can result in brain damage and death if it isn’t treated quickly.
Malaria has been eradicated in many european countries and from the US. Other parts of the world continue with eliminations programmes and also hope, one day, to eliminate the disease.
Malaria spreads when a mosquito becomes infected with the disease after biting an infected person, and the infected mosquito then bites a noninfected person. The malaria parasites enter that person's bloodstream and travel to the liver. When the parasites mature, they leave the liver and infect red blood cells.
Quinine is found in the bark of the cinchona tree; the tree is native to South America. Two French chemists isolated quinine from the bark in 1820 and quinine became the accepted treatment for malaria throughout the world; it remains an important and effective drug in the treatment of malaria to this day.
Chloroquine was developed by German scientists as a substitute for quinine in 1934; it was known as Resochin (chloroquine) and Sontochin (3-methyl-chloroquine). Two forms of malaria, those caused by P falciparum and P Vivax are resistant to chloroquine.
Sulfadoxine/Pyrimethamine was developed during world war 2. The subsequent development of resistance to this form of drug is causing a massive threat to the control of malaria across the planet.
Mefloquine was developed as a result of collaboration between the US Army Medical Research and Development Command, the World Health Organisation and Hoffman-LaRoche Inc..The efficacy of Mefloquine in preventing falciparum malaria when taken regularly was demonstrated in 1974 and subsequently its success as a drug for treating the disease was shown shortly afterwards.
Sadly, resistance to this drug appeared in Asia in 1985, just as the drug became generally available.
Artemisinin was isolated from Artemisia annua (sweet wormwood) in 1972 by Chinese scientists. The plant had been know to Chinese herbalists for more than 2000 years as Qinghao. Early studies by the scientists showed it to be equally effective as quinine and chloroquine at destroying the parasite and after human testing their studies were published in the Chinese medical journal in 1979.
Artemisinin is a highkly effective antimalarial medication which has proved to be even more powerful if used in conjunction with other anti-malarials. Artemisinin based combination therapy (ACT) has been proved to improve the efficacy of the drug as well as reducing the likelihood of the malaria developing resistance to the partner drug.
The use of ACT’s has proved to be a massive breakthrough in the world’s fight against malaria in the twenty first century.