Emerging viruses.
Hemorrhagic fever viruses are among the most dangerous biological agents known. New ones are discovered every year, and artificial as well as natural environmental changes are favoring their spread.
D000818:Animals; D006801:Humans; D012328:RNA Viruses / Q000472:pathogenicity*; D014777:Virus Diseases / Q000175:diagnosis / Q000209:etiology* / Q000517:prevention & control / Q000635:transmission