Surveillance data on notifiable infectious diseases were collected
from the National Notifiable Disease Surveillance
System (NNDSS) which is maintained by the Australia
Government Department of Health (DoH) [23]. Monthly
notifications (case numbers) aggregated at state/territory
and national level, were downloaded for the period
of January 2004 to September 2013. A full list of notifiable
diseases in Australia and case definitions can be
accessed through the DoH webpage [24]. Sixty-four diseases
are monitored and these are categorised in the
NNDSS as belonging to one of eight groups: bloodborne
diseases; gastrointestinal diseases; other bacterial
diseases; quarantinable diseases; sexually transmissible
infections; vector-borne diseases; vaccine preventable
diseases; and zoonoses. For the purpose of consistency,
we have reported diseases according to these groupings.
Whilst notifiable, data were not downloaded for human
immunodeficiency virus infection/acquired immunodeficiency
syndrome, Creutzfeldt–Jakob disease or variant
Creutzfeldt–Jakob disease because surveillance for
these diseases is not performed by DoH or for severe
acute respiratory syndrome, because reporting to the
DoH is informal; as such, these diseases are not listed
on the NNDSS.