*Senior Special Adviser; Chemical, Biological, Nuclear, Radiological, and Explosives Science and Operations; U.S. Department of Health and Human Services, Immediate Office of the Assistant Secretary for Preparedness and Response, 200 C Street, SW, Washington, DC 20024.
The author declares no conflicts of interest.
For correspondence contact the author at the above address, or email at [email protected].
(Manuscript accepted 21 August 2017)