Funding for this research was provided by:
Military Infectious Disease Research Program (F0580_19_WR_CS_)C)
Received: 17 November 2019
Accepted: 6 April 2020
First Online: 17 April 2020
Ethics approval and consent to participate
: The serum sample use was reviewed by the WRAIR Human Subjects’ Protection Branch which determined that the research does not involve human subjects (NHSR protocol WRAIR#2142) as the samples used were de-identified and no link between samples and subjects exists.
: Not applicable.
: The authors declare that they have no competing interests.