Funding for this research was provided by:
the National Natural Science Foundation of China ((2017) 81760605)
Received: 3 July 2018
Accepted: 28 September 2018
First Online: 22 November 2018
Ethics approval and consent to participate
: This research was approved by the Institutional Review Board at the Kenya Medical Research Institute, Kenya (SSC PROTOCOL NO.1698). All experiments were performed in accordance with approved guidelines and regulations.
: Not applicable.
: Authors declare no conflict of interest including any financial, personal or other relationships with other people or organization that could inappropriately influence, or be perceived to influence the work.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.