evidence: Under Section 361(b), the CDC's power to apprehend, detain, or conditionally release individuals is triggered by a finding that these actions are necessary to prevent the cross-border spread of a communicable disease that the president has designated as quarantinable in an executive order. Currently, the list of quarantinable diseases is limited to cholera, diphtheria, infectious tuberculosis, plague, smallpox, yellow fever, viral hemorrhagic fevers, severe acute respiratory syndromes, influenza viruses with pandemic potential, and measles.10 If the CDC sought to apprehend, detain, or conditionally release individuals based on the risk of any other communicable disease, the president would first have to issue an executive order amending the list of quarantinable diseases. The PHSA amendments in 2002 streamlined the process for updating the list. Section 361(c) specifies that these powers may be used to detain individuals entering the United States from a foreign country. [...] Regulations codified at 42 CFR §70.5, 70.6, 70.10, 70.12 et seq., and 71.29 et seq. (adopted in 2017) include extensive provisions to ensure the CDC orders for apprehension, screening, medical examination, isolation, quarantine, and conditional release are consistent with constitutional principles of federalism, separation of powers, and protections for individual rights (Gostin and Hodge, 2017).