This 2007 image depicted Centers for Disease Control microbiologists Dr. Thomas Stevens. Jr.. and Dr. Amy Hartman. as they were in the process of suiting up in order to access the interior of the organizationˇs Biosafety Level-4 (BSL-4) laboratory. Dr. Thomas was attaching his supportive air hose. which would provide a supply of filtered. breathable air. as well as maintaining 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.