Quality data on ME/CFS incidence and prevalence are scarce. In 2003, the ABDS included ME/CFS as a separate disease when considering incidence and prevalence estimates for the Australian population. Two possible presentations of ME/CFS described in the literature analysed by AIHW were:
a) Post-infective chronic fatigue syndrome (30-40% of patient cases)
b) Protracted chronic fatigue syndrome (60-70% of patient cases). Using data compiled for the 1993 ABDS (including estimated disability weight), AIHW concluded in 2003 that people with ME/CFS are symptomatic 90% of the time.
Median symptom duration ranges from 99% recovery after two years in post-infective fatigue syndrome to 50-80% recovery after 7 years in protracted chronic fatigue syndrome, when using the Fukuda (1994) diagnostic criteria for patient selection. 36
This is in contrast to recent paediatric data, which indicated that the majority of young people (who seemed to be more likely to have infection as a trigger) reported recovery after 4-5 years with a range of 1-15 years. By 5 years, 60% reported recovery and by 12 years 88% reported recovery. 16, 17
In the 2011 ABDS study, however, ME/CFS was excluded as a separate disease given the then outdated prevalence estimates used in the 2003 ABDS. Instead ME/CFS was included under ‘other neurological diseases.’ 37 These ‘other neurological conditions’ (including ME/CFS) were responsible for 9.8% of the total DALYs for neurological conditions in 2011.