Annals of Disaster Medicine

ISSN:1684-193X

Abstract ---Since last endemic smallpox in 1977, the variola virus can be detected only in some research institutes in the world. However, in fear of bioterrorism, the clinical manifestations that may be forgotten by emergency physicians have to be readdressed. Variola virus usually existed as two related strains: variola major with a mortality of 20 to 50%, and variola minor with a mortality of less than 1%. World Health Organization classification comprised another 3 additional types, that is, flat type, hemorrhagic type, and variola sine eruptione. The disease is highly contagious and spread by air droplets and direct contact with contaminants. Emergency reporting and pre-exposure vaccination are the most important steps in preventing epidemic, either from bioterrorism and the nature.