other treatments are  not  available, such as  Bolivian  and  Argentine hemorrhagic fevers ,  H5N1 ( bird flu ),  Dengue hemorrhagic fever ,  Marburg virus ,  Ebola virus ,  hantaviruses ,  Lassa fever ,  Crimean-Congo hemorrhagic fever ,  Y. pestis , and other  hemorrhagic diseases. When dealing with biological hazards at this level