This 2007 image depicted Centers for Disease Control microbiologists as they were in the process of suiting up in order to access the interior of the organization’s Biosafety Level-4 (BSL-4) laboratory. The scientist on the left was attaching his supportive air hose, which would provide a supply of filtered, breathable air, as well as maintain positive air pressure inside his air tight orange suit. The Special Pathogens Branch works with BSL-4 viruses. These viruses are highly pathogenic and require handling in special laboratory facilities designed to contain them. The Special Pathogens Branch mission focuses mainly on viral hemorrhagic fevers (VHFs), such as Ebola hemorrhagic fever, Lassa fever, hantavirus pulmonary syndrome (HPS), and hemorrhagic fever with renal syndrome (HFRS). Our work also includes the study of other emerging viral disease agents that do not cause hemorrhagic fever, but require BSL-4 handling, such as Nipah virus and tick-borne encephalitis virus.