Funding for this research was provided by:
U.S. President’s Emergency Plan for AIDS Relief (PS001468)
Text and Data Mining valid from 2018-03-31
First Online: 31 March 2018
Compliance with Ethical Standards
: The authors declare that they have no competing interests.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of The Ethical Review Board for Biomedical Research Hanoi University of Public Health and ADS of CDC and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: Informed consent was obtained from all individual participants included in the study.