The Queensland Bloodstream Infections (QBSI) study: rationale, protocol development and future directions

Area of Science:

• Infectious Diseases
• Epidemiology
• Public Health Surveillance

Background:

• High-quality bloodstream infection (BSI) surveillance data is crucial for effective control strategies.
• Population-based investigations into BSIs are currently limited globally.
• The Queensland BSI (QBSI) study addresses this gap by establishing comprehensive surveillance.

Purpose of the Study:

• To detail the rationale behind the Queensland BSI (QBSI) study.
• To describe the protocol development for this large-scale BSI surveillance program.
• To provide a model for other regions to develop similar BSI epidemiology studies.

Main Methods:

• Population-based laboratory surveillance of all BSIs in Queensland's public healthcare system (2000-2023).
• Linkage with hospital admissions and vital statistics for 1-year post-BSI outcomes.
• Standardized definitions for BSI episodes and classification by onset type.

Main Results:

• Over 3.7 million blood cultures processed, identifying 444,279 positive cultures.
• Extensive linkage data (2.4M+ hospital registrations, 10M+ ICD codes) analyzed.
• Comorbidities classified using ICD-based algorithms; 30, 90, and 365-day all-cause case-fatality assessed.

Conclusions:

• The QBSI study provides a robust framework for examining BSI epidemiology and outcomes in a large Australian population.
• Sharing experiences from the QBSI study aims to foster international collaboration.
• The ultimate goal is to accelerate BSI knowledge globally and reduce the disease burden.