Objectives Universal lockdown is a stringent type of public health measure. In Australia, most local outbreaks required mobility restriction to contain the spread of COVID-19 until successful vaccination roll-out. Each state and territory government had different approaches. In this analysis, the effect of lockdown on reducing COVID-19 hospitalisations is assessed and compared between three Australian states: New South Wales (NSW), Queensland (QLD) and Victoria (VIC).

Methods Data for COVID-19 cases, hospitalisations, vaccination rate and lockdown were obtained from state government websites. An analytic model was constructed to test the relationship between lockdown and hospitalisation. Lockdown and state were main predictor variables with hospitalisation being the dependant variable. Other predictor variables likely to have an effect included active cases and vaccination. Analyses were performed in Excel and SAS.

Results Overall, the analysis found that hospitalisation was significantly associated with lockdown (p<0.0001). QLD had the lowest hospitalisations (mean=16.98, SD=16.89) and shortest lockdown period (54 days out of 596 days). When compared with VIC where lockdown was longest (273 days out of 596 days) and hospitalisations were higher (mean=95.15, SD=198.82), the effect of lock-down on hospitalisation was not significantly different (p=0.076) between QLD and VIC. On the other hand, when VIC is compared with NSW, where lockdown was shorter (174 days out of 596 days) and hospitalisations were highest (mean=131.53, SD=301.23), the effect of lockdown was significantly different (p<0.0001). The percentage of active hospitalised cases was similar between NSW and VIC (4.4% and 4.8% respectively) but was much lower in QLD (<1%), confirming QLD was the least Covid-19 affected state.

Conclusions Our analysis indicates that lockdown is associated with reduction of hospitalisations. VIC and QLD have largely different number of days in lockdown; however the impact of lockdown was not significantly different. This could imply that hospitalisations were effectively brought down with its lock-down strategy in VIC.