Australian Meningococcal Surveillance Programme Annual Report, 2024.

Area of Science:

• Epidemiology
• Microbiology
• Public Health

Background:

• Invasive meningococcal disease (IMD) is a significant public health concern in Australia.
• Surveillance of IMD is crucial for understanding disease trends and guiding public health interventions.

Purpose of the Study:

• To report on the epidemiology and laboratory characteristics of invasive meningococcal disease (IMD) cases in Australia for 2024.
• To analyze serogroup distribution, antimicrobial susceptibility, and demographic patterns of IMD.

Main Methods:

• Data collected through the National Notifiable Diseases Surveillance System (NNDSS).
• Laboratory confirmation using bacterial culture and nucleic acid amplification testing.
• Serogroup determination, porA finetyping, and antimicrobial susceptibility testing (AST) of isolates.

Main Results:

• A 5% decrease in IMD notifications compared to 2023, with 136 cases reported.
• Serogroup B (MenB) was the predominant serogroup (84%), followed by MenY (14%).
• Highest incidence occurred in children under 5 years and young adults aged 15-24 years, with MenB dominating both groups. Penicillin resistance was observed in 7% of isolates, with intermediate susceptibility in 60%.

Conclusions:

• Invasive meningococcal disease (IMD) remains a concern, with MenB being the primary driver.
• Age-specific incidence highlights key populations for targeted surveillance and potential interventions.
• While most isolates remain susceptible to ceftriaxone, ciprofloxacin, and rifampicin, evolving penicillin resistance patterns warrant continued monitoring.