Influenza pandemic modelling for South Africa with an analysis of the predicted impact on the healthcare sector

Abstract

The predicted impact of a potential future influenza pandemic was modelled for South Africa using a multi-state Markov transition model based on key parameters from the pandemics of the twentieth century. The number of individuals falling into each of the following categories was predicted for each week in the pandemic: healthy (uninfected); infected (no treatment); infected (out-patient treatment); infected (hospital admission); infected (ICU admission); healthy (flu recovery) and dead. Four scenarios were modelled. The Mild and Severe Pandemic Scenarios were then applied to estimations of current hospital and ICU bed spare capacity in each province to provide a prediction of the impact of a pandemic on hospital capacity. The Mild Pandemic Scenario, based on the 1957 and 1968 pandemics, showed a 9.1% total infection rate and a 0.13% mortality rate. Hospital bed capacity is stretched close to capacity, but does not exceed capacity in any province. ICU bed capacity is exceeded for all provinces during the peak of the pandemic (3-7 weeks). The Severe Pandemic Scenario, based on the 1918 pandemic, had a 22% total infection rate with a 2.5% mortality rate. Hospital and ICU bed capacities were exceeded in all provinces for much of the pandemic.