Résumé
In Burkina Faso, in rural Mossi areas, popular contemporary representations of the transmission of HIV from mother to child are based on the idea that "the disease is in the blood" and that the fetus is conceived by "mixing the blood" of its parents. Infection of the child is seen as inevitable and systematic and is believed to occur in utero. Maternal milk is thought to have the same potential for infection because "milk is blood" but its role in transmission is seen as secondary, with transmission occurring before birth. However, breast feeding is believed to be responsible for the transmission of the disease in two ways: 1) by infected women transmitting the illness to healthy children via their milk and 2) by healthy women becoming infected by breast feeding infants born to infected mothers. The belief that transmission is systematic and the fear that the child will contaminate others leads to the widely held view within the population that no care should be taken of children born to women with AIDS and that such children should be abandoned and left to die. These representations have recently developed in the population based on preexisting beliefs relating to the physiology and role of blood in the transmission of diseases and the health information that has been distributed. Health information messages are largely responsible for the representations described above. Indeed, the description of the modes of HIV transmission in such messages has been based on the simplified statement of the triad, sex, blood and mother-child, with no indication of the relative risks of transmission for each. Hence, this incomplete information, interpreted in terms of popular conceptions about contagion, has resulted in maximal probability being attributed to each of the listed modes of transmission. Health information messages are the principal means of communicating scientific information to the general population. The stakes associated with the quality and correctness of the information supplied are therefore very high. The notion of the risk of transmission and statement of the level of risk are essential to any explanation of the modes of transmission of HIV. These ideas cannot be neglected because they are essential to the correct understanding of transmission and to the logical management of individual risk.