Figure 4. Global spread of dengue virus 3 (DENV-3), subtype III, which has been continuously circulating in the Indian subcontinent from the 1960s to the present. The virus was first isolated from East Africa in 1985 in Mozambique and subsequently from Kenya (1991) and Somalia (1993) (32,33). DENV-3 subtype III was first detected in the American continent in 1994 (Nicaragua and Panama) and the virus has subsequently spread through most of Latin America (13,14,16,29,30). The arrows depict the most likely directions of spread based on the phylogenetic relationships between the viruses (see text for details). The map also displays countries in which dengue is known to occur.