Development of a control strategy towards elimination of Trypanosoma evansi infection (surra) in camels in Africa.

With an increasing worldwide population that presently exceeds 38 million, camels are important source of meat, milk, and transportation of goods, in many regions of the world. Camels are particularly critical in the northern parts of Africa, above the tsetse belt. However, camel breeding areas are expanding into southern areas, under the pressures of global warming, leading to increasing risk of acquiring parasitic infections in these non-traditional ecotypes. Common biting flies (tabanids, stomoxyine flies, and Hippobosca camelina) act as mechanical vectors, resulting in exposure to trypanosomosis (Trypanosoma evansi; Surra) and high camel morbidity and mortality. In these regions, complicating infections with other Trypanosoma may also occur, particularly Trypanosoma vivax. In many modern camel-breeding areas, human populations are living under political upheaval (terrorism, riots), poverty, and precarity (drought, climate modification). Hence, control and/or elimination of Surra in camels would be beneficial to the economies of these populations. Due to the relatively straightforward epidemiology (single parasite with seasonal transmission in a single host species), control of Surra in Africa is affordable and should be based on implementing: (1) national veterinary services capabilities; (2) efficient diagnosis and control methods; (3) joint integrated control of Surra, gastrointestinal helminthoses (mainly haemonchosis), and sarcoptic mange. We propose that methods to control two economically-critical disease problems, gastrointestinal parasitosis and sarcoptic mange, will support improved Surra control in camels. Aided by decision-makers and donors, elimination of Surra could improve camel health and productivity, and stabilize camel-rearing in regions of the world that suffer from political instability and global warming pressures.