Funding for this research was provided by:
the National Natural Science Foundation of China (81703279)
Sichuan Science and Technology Program (2019YJ0148)
National Major Science and Technology Projects of China: Study on the assessment technology and prediction model of AIDS epidemic in China (2017ZX10201101)
Received: 19 May 2020
Accepted: 13 August 2020
First Online: 26 August 2020
Ethics approval and consent to participate
: All subjects voluntarily participated in our study and signed informed consent forms before enrollment. The study protocol was approved by the Ethics Committee of the Sichuan Center for Disease Control and Prevention (201303), and the study was carried out following the Helsinki Declaration of 1964.
: Not applicable.
: The authors declare that they have no competing interests.