Dengue fever the same genus include yellow fever virus, West Nile virus, Zika virus, St. Louis encephalitis virus, Japanese encephalitis virus, tick-borne encephalitis virus, Kyasanur forest disease virus, and Omsk hemorrhagic fever virus. Most are transmitted by arthropods (mosquitoes or ticks), and are therefore also referred to as arboviruses ("ar"thropod-"bo"rne viruses). The dengue virus genome (genetic material) contains about 11,000 nucleotide bases, which code for the three different types of protein molecules (C, prM and E) that form the virus particle and seven other non-structural protein molecules (NS1, NS2a, NS2b, NS3, NS4a, NS4b, NS5) that are found in infected host cells only
History of yellow fever The entire Mississippi River Valley from St. Louis south was affected, and tens of thousands fled the stricken cities of New Orleans, Vicksburg, and Memphis. An estimated 120,000 cases of yellow fever resulted in some 20,000 deaths. Memphis suffered several epidemics during the 1870s, culminating in the 1878 epidemic (called the Saffron Scourge of 1878), with more than 5,000 fatalities in the city. Some contemporary accounts said that commercial interests had prevented the rapid reporting of the outbreak of the epidemic, increasing the total number of deaths. People still did not understand how the disease developed or was transmitted, and