1. Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
2. Department of Allied Health Sciences, University of Connecticut, Storrs, CT, USA
3. Department of Behavioral and Community Health Sciences, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
4. Institute of Social and Medical Studies, Hanoi, Vietnam
5. Hanoi Medical University, Hanoi, Vietnam
6. Department of Public Health Sciences, University of Connecticut School of Medicine, Farmington, CT, USA