Advances in Parasite Control in Africa: From Basic Science to Translation

Parasitology as a subject has a long history in Africa both in the medical and veterinary fields ranging from the identification of parasites to the development of interventions. For example, both of the parasites of major public health concern in tropical countries were discovered in Africa despite occurring in other parts of the world. Thus, the Plasmodium parasite causing malaria was discovered by Charles Louis Alphonse Laveran, a French army surgeon stationed in Constantine, Algeria, on the 6th of November 1880, a discovery for which he was awarded the Nobel Prize in 1907. The livestock protozoan Theileria parva, which causes East Coast Fever in cattle, was also discovered in Africa by Arnold Theiler and Charles Lounsbury in South Africa in 1904. In 1851, Theodor Bilharz, discovered the blood fluke parasite (Schistosoma haematobium) which causes bilharzia or snail fever, during a postmortem examination at the Kasr-el-Aini hospital in Cairo. Since these discoveries, there have been concerted efforts worldwide to find interventions ranging from drugs used to kill parasites in human hosts (quinine; artemisinins for Plasmodium and the antihelminthics metrifonate; oxam-niquine and praziquantel for schistosomes), drugs to kill vectors/intermediate hosts (dichlorodiphenyltrichloroethane (DDT) for Plasmodium mosquito vectors; acaricides for tick vectors of Theileria and copper sulphate/niclosamide for killing schistosome snail hosts), and barriers to prevent the contact of human hosts and infective stages (e.g., bed nets for Plasmodium). With the description of life cycles of not only these parasites but other protozoans (e.g., Giardia) and helminths (e.g., hookworms), the importance of sanitation, hygiene and clean water became apparent, and these lead to inventions such as the Blair toilet, a simple pit latrine developed in Zimbabwe and safe drinking water wells. These developments hold true to the observation by the Roman Scholar and Scientist Pliny the Elder (23 AD–79 AD) that " there is always something new out of Africa, " albeit it is in a different context. With technological advances in this postgenomic era, collaborations between scientists in different institutions and countries in Africa as well as collaborations between African scientists and those in other continents (loosely termed north-south collaborations) have allowed scientists to conduct cutting-edge target-species-oriented research. The development and fostering of these collaborations and partnerships themselves have been as vital as the technological advances in efforts to control parasitic diseases. Thus, for example, work on RTS,S, the world's most clinically advanced malaria vaccine candidate [1], has included 11 clinical trial sites …