Epidemiology of invasive pneumococcal disease among children aged 0–5 years in Thailand, 2023–2025
DOI:
https://doi.org/10.59096/wesr.v57i2.7435Keywords:
Streptococcus pneumoniae, epidemiology, burden of disease, ThailandAbstract
Introduction: Invasive Pneumococcal Disease (IPD) is a leading cause of morbidity and mortality among children aged 0–5 years, particularly those under the age of two. Despite the availability of effective vaccines, the IPD vaccine has not yet been included in Thailand's National Immunization Program (NIP). Furthermore, data regarding the disease burden and epidemiology remain unclear. This study aims to estimate the disease burden and describe the epidemiological characteristics of IPD in children aged 0–5 years in Thailand during 2023–2025.
Methods: A cross–sectional study was conducted using retrospective data from 2023–2025. Data sources included the Digital Disease Surveillance system, laboratory surveillance system, population data from the Department of Provincial Administration, and literature reviews. The study estimated the number of IPD cases based on total occurrences of pneumonia, meningitis, and encephalitis in children aged 0–5 years. Epidemiological descriptions were categorized by person, time, and place.
Results: Between 2023 and 2025, a total of 5,217 IPD cases were reported among children aged 0–5 years in Thailand, with a female–to–male ratio of 1:1.36. The annual incidence rates were 47.35, 60.98, and 61.24 per 100,000 population, respectively. Two seasonal peaks were observed annually. Major wave during August to October (Rainy season), with 200–300 cases per month. Minor wave during December to February (Winter season), with 150–200 cases per month. Geographically, cases were distributed across all provinces. By 2025, the majority of provinces reported incidence rates exceeding 40 per 100,000 population.
Discussion and recommendations: The incidence of IPD among children aged 0–5 years in Thailand is trending upward and is widespread nationwide. Given the availability of highly effective vaccines, this study recommends that the Thai government incorporate the IPD vaccine into the NIP to ensure equitable access for all children. Additionally, the surveillance system should be enhanced to improve IPD detection and provide more precise situational assessments.
References
Centers for Disease Control and Prevention (US). Pink book: pneumococcal disease [Internet]. Atlanta: CDC; 2024 [cited 2026 Feb 1]. Available from: https://www.cdc.gov/pinkbook/hcp/table-of-contents/chapter-17-pneumococcal-disease.html
Public Health Agency of Canada. Pathogen safety data sheets: Streptococcus pneumoniae [Internet]. Ottawa: Government of Canada; 2011 [cited 2026 Feb 1]. Available from: https://www.canada.ca/en/public-health/services/laboratory-biosafety-biosecurity/pathogen-safety-data-sheets-risk-assessment/streptococcus-pneumoniae.html
Centers for Disease Control and Prevention (US). Invasive pneumococcal disease (IPD) 2017 case definition [Internet]. Atlanta: CDC; 2017 [cited 2026 Feb 1]. Available from: https://ndc.services.cdc.gov/case-definitions/invasive-pneumococcal-disease-2017/
Narciso AR, Dookie R, Nannapaneni P, Normark S, Henriques–Normark B. Streptococcus pneumoniae epidemiology, pathogenesis and control. Nat Rev Microbiol. 2025;23(4):256–71.
Chen H, Matsumoto H, Horita N, Hara Y, Kobayashi N, Kaneko T. Prognostic factors for mortality in invasive pneumococcal disease in adult: a system review and meta–analysis. Sci Rep. 2021;11(1):11865.
European Centre for Disease Prevention and Control. Invasive pneumococcal disease [Internet]. Stockholm: ECDC; 2024 [cited 2026 Feb 1]. Available from: https://www.ecdc.europa.eu/en/invasive-pneumococcal-disease
World Health Organization. Pneumococcal conjugate vaccines in infants and children under 5 years of age: WHO position paper – February 2019. Weekly Epidemiol Rec. 2019;94(8):85–104.
GBD 2021 Lower Respiratory Infections and Antimicrobial Resistance Collaborators. Global, regional, and national incidence and mortality burden of non-COVID-19 lower respiratory infections and aetiologies, 1990–2021: a systematic analysis from the Global Burden of Disease Study 2021. Lancet Infect Dis. 2024;24(9):974–1002.
Said MA, Johnson HL, Nonyane BA, Deloria-Knoll M, O'Brien KL; AGEDD Adult Pneumococcal Burden Study Team, et al. Estimating the burden of pneumococcal pneumonia among adults: a systematic review and meta–analysis of diagnostic techniques. PLoS One. 2013;8(4):e60273. doi:10.1371/journal.pone.0060273
GBD 2019 Meningitis Antimicrobial Resistance Collaborators. Global, regional, and national burden of meningitis and its aetiologies, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019. Lancet Neurol. 2023;22(8):685–711.
UNICEF. Child health: Pneumonia [Internet]. New York: UNICEF; 2023 [cited 2026 Feb 5]. Available from: https://data.unicef.org/topic/child-health/pneumonia/
Ministry of Public Health (TH), Strategy and Planning Division. Vital statistics dashboard [Internet]. Nonthaburi: Ministry of Public Health; 2025 [cited 2026 Feb 1]. Available from: https://vitalstat.moph.go.th/ (in Thai)
Centers for Disease Control and Prevention (US). Active Bacterial Core Surveillance Report, Emerging Infections Program Network, Streptococcus pneumoniae, 2021 [Internet]. Atlanta: CDC; 2021 [cited 2026 Feb 1]. Available from: https://www.cdc.gov/abcs/downloads/spn_surveillance_report_2021.pdf
Ministry of Public Health (TH), Department of Disease Control, Division of Epidemiology. Surveillance system for communicable diseases [Internet]. Nonthaburi: Division of Epidemiology; 2026 [cited 2026 Feb 1]. Available from: https://ddc.moph.go.th/doe/pagecontent.php?page=607&dept=doe (in Thai)
Yoon YK, Yang KS, Sohn JW, Lee CK, Kim MJ. Impact of preceding respiratory viral infections on the clinical severity of patients with pneumococcal pneumonia. Influenza Other Respir Viruses. 2014;8(5):549–56.
Centers for Disease Control and Prevention (US). Pneumococcal disease surveillance and reporting [Internet]. Atlanta: CDC; 2024 [cited 2026 Feb 1]. Available from: https://www.cdc.gov/pneumococcal/php/surveillance/index.html
Mohanty S, Podmore B, Cuñado Moral A, Matthews I, Sarpong E, Lacetera A, et al. Incidence of pneumococcal disease from 2003 to 2019 in children ≤17 years in England. Pneumonia (Nathan). 2023;15(1):2.
Chang CY, Nasreen S, Sadarangani M, Aquino K, Cragg JJ, Marra F. Effectiveness of vaccine dosing schedules for pneumococcal invasive disease in children: a systematic review and meta–analysis. Vaccine X. 2025;27:100734.
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