Received: 22 October 2017
Accepted: 29 January 2018
First Online: 2 February 2018
: All the animal experiments were performed according to the protocol approved by the Institutional Animal Care and Use Committee by the Nippon Institute for Biological Science.
: Not applicable.
: All of the authors are members of Nippon Institute for Biological Science (NIBS). Nisseiken Co., Ltd. distributes the vaccine developed by NIBS; however, NIBS is not led in any way by the company. NIBS members determine meeting agenda items and lead the discussions and outputs.
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