1. Department of Pathology, Johns Hopkins School of Medicine, Baltimore, MD 21287, USA.
2. Center for Microbial Genetics and Genomics, Northern Arizona University, Flagstaff, AZ 86011, USA.
3. Division of Pathogen Genomics, Translational Genomics Research Institute, Flagstaff, AZ 86001, USA.
4. Department of Environmental and Occupational Health, Milken Institute School of Public Health, The George Washington University, Washington, DC 20052, USA.
5. Center for Ecosystem Science and Society, Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA.
6. Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
7. The Danish Twin Registry, University of Southern Denmark, Odense, Denmark.
8. Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark.
9. Microbiology and Infection Control, Statens Serum Institut, Copenhagen, Denmark.
10. Department of Veterinary Disease Biology, University of Copenhagen, Copenhagen, Denmark.