RESUMO
Introduction: Accurate; comprehensive knowledge of an infectious pathogen's modes of transmission helps people to avoid infection. Growing evidence suggests that blood-borne HIV transmission is widespread in sub-Saharan Africa. Methodology: I examined the association between knowledge of blood-borne HIV risk and prevalent HIV infection in Demographic and Health Survey data from 16 sub-Saharan African countries. I also searched three online databases for evidence of public education campaigns focused on blood-borne HIV risks in these countries. Results: Knowledge was moderately to strongly inversely related to HIV prevalence at the national level (i.e.; countries in which many respondents were aware of blood-borne risk had lower HIV prevalence than countries in which few respondents were aware of such risk). At the individual level; respondents who knew about blood-borne HIV risks were modestly less likely to be infected than those who did not show awareness of this risk; independent of demographic and sexual behavior variables. This relationship was stronger in southern Africa than in west; central; and east Africa. In parallel analyses; knowledge of condom use as a way to prevent HIV was positively associated with prevalent HIV infection at both the national and individual levels. West; central; and east African countries with low to moderate HIV prevalence had implemented public education campaigns that included a focus on blood-borne transmission risks. Such campaigns were absent from high prevalence countries in southern Africa. Conclusion: These findings suggest that knowledge of blood-borne HIV risk protects against HIV infection and that public education campaigns are important for spreading that knowledge