[1] Canberra Hosp, Infect Dis Unit, Canberra, ACT, Australia
[2] Canberra Hosp, Dept Microbiol, Canberra, ACT, Australia
[3] Australian Natl Univ, Sch Clin Med, Canberra, ACT, Australia
[4] Dept Infect Dis, Melbourne, Vic, Australia
[5] Monash Univ, Dept Epidemiol & Prevent Med, Melbourne, Vic 3004, Australia
[6] Univ Melbourne, Dept Med, Melbourne, Vic, Australia