Experts from the journal Public Library of Science journal PloS Medicine are concern that the Bubonic Plague are on the rise again with the general population being unaware. "Although the number of human cases of plague is relatively low, it would be a mistake to overlook its threat to humanity, because of the disease's inherent communicability, rapid spread, rapid clinical course, and high mortality if left untreated." Globally the World Health Organization reports about 1,000 to 3,000 plague cases each year, with most in the last five years occurring in Madagascar, Tanzania, Mozambique, Malawi, Uganda and the Democratic Republic of Congo, while the United States sees about 10 to 20 cases each year. The most recent large pneumonic outbreak comprised hundreds of suspected cases in the Democratic Republic of Congo in 2006.
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