Invasive group B streptococcal infections in Western Australia, 2000-2018

Area of Science:

• Infectious Diseases
• Epidemiology
• Public Health

Background:

• Neonatal and puerperal sepsis are key manifestations of invasive group B streptococcal (Streptococcus agalactiae; iGBS) infections.
• International data highlight the significance of iGBS infections in non-pregnant adults.

Purpose of the Study:

• To determine the incidence, hospitalization duration, and mortality rates (30- and 90-day) of iGBS infections in Western Australia (WA) from 2000 to 2018.

Main Methods:

• A retrospective, population-based study utilizing linked data from pathology, hospitalizations, and death registrations.
• Included were children and adults with GBS isolated from sterile sites or diagnosed with hospital-based iGBS infection.

Main Results:

• 2861 cases were identified; 768 (26.8%) were infants (0-1 year).
• Incidence rose over the study period, reaching 9.5 cases per 100,000 population in 2018.
• While infant cases decreased proportionally, older age groups showed increased relative incidence; 30-day mortality was 3%.

Conclusions:

• iGBS cases in WA increased between 2000-2018, with a notable rise in older adults.
• Preventive measures, potentially including vaccination, should focus on older populations to mitigate this trend.