[1] Univ Washington, Dept Med, Div Gen Internal Med, 325 9th Ave, Seattle, WA 98104 USA
[2] Univ Calif San Francisco, Dept Epidemiol & Biostat, 550 16th St,Second Floor, San Francisco, CA 94158 USA
[3] Univ Calif San Francisco, Dept Med, 3333 Calif St,Suite 430, San Francisco, CA 94118 USA
[4] Univ New South Wales, Kirby Inst, UNSW Australia, Wallace Wurth Bldg, Sydney, NSW 2052, Australia
[5] Univ Montreal, Ctr Rech CHUM, 900 Rue St Denis, Montreal, PQ H2X 0A9, Canada
[6] Burnet Inst, 85 Commercial Rd, Melbourne, Vic 3004, Australia
[7] Harvard Med Sch, 25 Shattuck St, Boston, MA 02115 USA
[8] Johns Hopkins Med Inst, Dept Med, 1830 E Monument St, Baltimore, MD 21287 USA
[9] GGD Publ Hlth Serv Amsterdam, Cluster Infect Dis, Nieuwe Achtergracht 100,1018 WT Amsterdam, NL-1000 CE Amsterdam, Netherlands
[10] Univ New South Wales, Sch Med Sci, UNSW Australia, Wallace Wurth Bldg, Sydney, NSW 2052, Australia
[11] Univ New Mexico, Dept Internal Med, Div Epidemiol Biostat & Prevent Med, Hlth Sci Ctr, 1 Univ New Mexico, Albuquerque, NM 87131 USA