The species Aedes albopictus is an efficient vector of dengue in Asia and possibly of other arboviruses, including yellow fever and encephalitis. The distribution of A. albopictus has been extended to America in the last decade. The presence of this species was reported in the city of Tabatinga in Brazil, near the border with Colombia, in 1996 and again in October 1997. During an epidemiological study of tropical diseases carried out in March 1998 by the Programa de Estudio y Control de Enfermedades Tropicales, PECET, of the Universidad de Antioquia and the Secretaría de Salud del Amazonas, adult specimens of A. albopictus were collected in the city of Leticia, in the Amazonas' Department, this being the first time that this species has been found in Colombia. The presence of A. albopictus complicates dengue transmission, dueto: the better adaptation of this vector species to cooler weather; its transovarial transmission capacity; its positive vectorial capability to transmit the virus' 4 serotypes; and the increased difficulty for vector control, given that A. albopictus' breeding places are in peridomestic and rural areas. The distribution of this species in sylvatic, rural and urban areas represents a potential danger of yellow fever transmission urbanisation. To avoid the propagation of this vector species to other parts of the country, a contingency plan was adopted by the Secretaría de Salud del Amazonas, which is presented in this paper.