Twenty-Five Year Trend Change in the Etiology of Pediatric Invasive Bacterial Infections in Korea, 1996-2020.

Background: The coronavirus disease-2019 (COVID-19) pandemic has contributed to the change in the epidemiology of many infectious diseases. This study aimed to establish the pre-pandemic epidemiology of pediatric invasive bacterial infection (IBI).
Methods: A retrospective multicenter-based surveillance for pediatric IBIs has been maintained from 1996 to 2020 in Korea. IBIs caused by eight bacteria ( Streptococcus pneumoniae , Haemophilus influenzae , Neisseria meningitidis , Staphylococcus aureus , Streptococcus agalactiae , Streptococcus pyogenes , Listeria monocytogenes , and Salmonella species) in immunocompetent children > 3 months of age were collected at 29 centers. The annual trend in the proportion of IBIs by each pathogen was analyzed.
Results: A total of 2,195 episodes were identified during the 25-year period between 1996 and 2020. S. pneumoniae (42.4%), S. aureus (22.1%), and Salmonella species (21.0%) were common in children 3 to 59 months of age. In children ≥ 5 years of age, S. aureus (58.1%), followed by Salmonella species (14.8%) and S. pneumoniae (12.2%) were common. Excluding the year 2020, there was a trend toward a decrease in the relative proportions of S. pneumoniae (r _s = -0.430, P = 0.036), H. influenzae (r _s = -0.922, P < 0.001), while trend toward an increase in the relative proportion of S. aureus (r _s = 0.850, P < 0.001), S. agalactiae (r _s = 0.615, P = 0.001), and S. pyogenes (r _s = 0.554, P = 0.005).
Conclusion: In the proportion of IBIs over a 24-year period between 1996 and 2019, we observed a decreasing trend for S. pneumoniae and H. influenzae and an increasing trend for S. aureus , S. agalactiae , and S. pyogenes in children > 3 months of age. These findings can be used as the baseline data to navigate the trend in the epidemiology of pediatric IBI in the post COVID-19 era.
Competing Interests: The authors have no conflicts of interest to disclose.
(© 2023 The Korean Academy of Medical Sciences.)