The Round Table organized by the Société de pathologie exotique during the 3rd European Congress on Tropical medicine and International Health held in Lisbon on September 9, 2002 has been attended by a hundred participants. Five communications were presented and followed by a debate concerning the main aspects of the epidemiology and the control of
schistosomiasis in sub-Saharan Africa. The necessity of studying intermediate hosts to identify vectors, some of which being able to colonize new areas or to modify their susceptibility to parasites, has been emphasized. The population is infected during water contacts and Poda et al. showed the importance of water projects, necessary for the development of poor countries, but facilitating the transmission of
schistosomiasis. Most current activities force the population to use stagnant water However, it is well known that children are more infected, with severe clinical and functional consequences. The contamination of the environment is linked to hygienic practices. Sow et al. demonstrated that usually recommended solutions are inappropriate. Latrines, for example, are notably sub-used by some at risk groups because culturally unsuitable and considered as avoiding discretion or comfort. Besides the technical improvement which can be proposed, education by the parents and the teachers must begin from the youngest age. Ernould et al. showed the strong heterogeneity of
schistosomiasis transmission in water projects due notably to the distance between habitations and transmission sites as well as modalities of use and maintenance of the irrigation system. In this respect, the communication of Poda et al. showed that
schistosomiasis was underestimated by the health system due to the lack of training of health staff, poor equipment of health centers and low awareness of both populations and political authorities. Garba et al. confirmed the efficiency of mass treatments with
praziquantel, even with a low therapeutic coverage. The renewal of the treatment can be adapted to the intensity of the transmission. The modeling of the performances of the
hematuria test described by Etard allows to adjust the sample of population participating to a survey. Other indicators must be proposed to estimate the efficiency of the strategy of control and, possibly, to adapt it to local constraints. Ultrasonographic scores have been proved as faithful and specific indicators for clinical surveillance of complications. Several participants evoked the promising experimental results of candidate
vaccines against
schistosomiasis and noticed delay taken by clinical trials. The weakness of the financial support postponed considerably the development of the
vaccines which interests a numerous population but unable to pay for them. Participants insisted on health education, hygiene, construction or modernization of infrastructures and sanitation which, together, will guarantee durability. Mass treatment with
praziquantel appears as a method, certainly indispensable at this stage, but which must be transient. A wide consensus emerged in favor of a community based and integrated control strategies organized at peripheral level in association with technical services (health, hydraulics, agriculture, education) and local governments. Although
schistosomiasis seems not to drain any more financial supports, restricting human and scientific resources mobilization of industrial countries, this Round Table underlined the dynamism of researches performed by sub-Saharan African scientists.