Invasive pneumococcal disease in children: geographic and temporal variations in incidence and serotype distribution

Area of Science:

• Epidemiology
• Infectious Diseases
• Pediatrics

Background:

• Invasive pneumococcal disease (IPD) poses a significant global health burden, particularly in young children.
• Understanding geographic and temporal variations in IPD epidemiology is crucial for effective public health strategies.

Purpose of the Study:

• To analyze geographic and temporal variability in IPD epidemiology among young children.
• To compare IPD incidence and serogroup distribution between the United States, Europe, and Latin America.

Main Methods:

• Systematic review of published studies from the United States, Europe, and Latin America.
• Analysis of surveillance data from the US Centers for Disease Control and Prevention (CDC) and the Danish national surveillance system.
• Retrospective analysis of hospital data spanning up to 40 years.

Main Results:

• US IPD incidence in children under 5 years has shown little temporal variation over the past 5 years.
• Denmark reported a 3-4 fold increase in bacteremic IPD in children under 5 over 15 years, yet US incidence remains 4-8 fold higher.
• Seven vaccine-targeted serogroups consistently account for 80%-90% of IPD in North American children, compared to 10%-20% less in European children.

Conclusions:

• Apparent temporal and geographic differences in IPD epidemiology may be influenced by variations in blood culturing rates.
• Antibiotic resistance levels and precise age distributions of studied populations likely contribute to observed epidemiological disparities.
• Consistent dominance of vaccine serogroups in causing IPD highlights the importance of pneumococcal conjugate vaccines.