1. Department of Epidemiology of Microbial Diseases, Yale School of Public Health , New Haven , USA
2. Public Health Modeling Unit, Yale School of Public Health , New Haven , USA
3. Department of Health Policy and Management, Yale School of Public Health, New Haven , Connecticut , USA
4. Bureau of Infectious Disease and Laboratory Sciences, Massachusetts Department of Public Health , Boston , USA
5. Department of Biostatistics, Yale School of Public Health , New Haven, Connecticut , USA