Funding for this research was provided by:
National Natural Science Foundation of China (81290342, 31560049)
Yunnan Province Applied Basic Research Projects (2016FB029)
The National Key R&D Program of China (2016YFC1201904)
Development Grant of State Key Laboratory of Infectious Disease Prevention and Control (2014SKLID103)
Received: 23 May 2018
Accepted: 11 December 2018
First Online: 11 January 2019
Ethics approval and consent to participate
: This research, including the procedures and protocols of specimen collection and processing, was reviewed and approved by the Medical Ethics Committee of the Yunnan Institute of Endemic Diseases Control and Prevention.
: Not applicable.
: The authors declared that they had no competing interests.
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