Healthcare-associated Staphylococcus aureus bacteraemia: Te Whatu Ora – Health New Zealand districts

Continuous ongoing surveillance of healthcare-associated Staphylococcus aureus bacteraemia (HA-SAB) is an important quality activity that make care safer and guides strategies to improve clinical practice. 

This report summarises results from the first 12 months of this surveillance across all districts of Te Whatu Ora – Health New Zealand, from 1 July 2022 to 30 June 2023. Data was extracted on 14 August 2023.

The key findings are as follows.

• There were 471 HA-SAB events in total, which amounts to 1–2 events occurring each day within district hospitals. The absolute number per district ranged from 0 to 98.
• Of those patients with HA-SAB, 63.5 percent were European or other, 19.5 percent were Māori, 11.3 percent were Pacific peoples and 5.7 percent were Asian.
• Methicillin-susceptible S. aureus accounted for 87.3 percent of cases and methicillin-resistant S. aureus (MRSA) accounted for 12.7 percent of cases. MRSA is more common in the North Island.
• Medical devices were the source for just under three-quarters (71.1 percent) of all HA-SAB events, followed by organ source (not surgical site infection (SSI) at 13.2 percent and SSI at 8.5 percent).
• All ethnic group data was age standardised using Census data to have identical age structures. This showed the highest expected HA-SAB rate was for Pacific peoples followed by Māori. Likewise, applying the same approach for HA-SAB related to central vascular catheter or peripheral intravascular catheter use, the highest expected HA-SAB rate was also for Pacific peoples followed by Māori.