Pediatric invasive meningococcal disease in Türkiye during the post-pandemic period: increased reported cases and predominance of serogroup B and severity determined by a clinical form in a multicenter hospital-based cohort

Cakmak Taskin, Esra; ARGA, GÜL; Arslan, Basak; Taskin Karacay, Isil; Genceli, Mustafa; Erdeniz, Emine; Kaba, Ozge; Avcu, Gulhadiye; Kus, Sevgi; Abaci Capar, Meryem; Kacmaz, Behiye; Alkan, Gulsum; Yasar Durmus, Sevgi; Bostan, Aysenur; Acik, Ayse; Aksoy, Fatma; Celik, Taylan; Efendi Kocagoz, Mehlika; Sener Okur, Dicle; Tekin Yilmaz, Ayse; Oksuzoglu, Erdem; SEYHANLI, DAMLA; Gokay, Nahide; Agrali Eroz, Nesli; Sinav Utku, Hatice; Bayhan, Cihangul; Ozlu, Canan; Lacinel Gurlevik, Sibel; Sutcu, Murat; Kizil, MAHMUT; Celebi Congur, Emel; ÜMİT, ZÜHAL; Sahin, Aslihan; Bursal, Burcu; Kandemir Gulmez, Tugba; Baysal, Meryem; Sahin Izci, Eda; Kilinc, Fatma; Ersozlu, YASEMİN; Deniz, Melis; Mete Atasever, Neslihan; Celik, Nermin; Turan, Cansu; Cicek, Alper; Korulmaz, Ali; Yahsi, Aysun; Yesil, Edanur; KARA AKSAY, Ahu; Bayturan, Semra; ÇELİK, Ümit; ÖZKAYA PARLAKAY, ASLI; Metin Akcan, Ozge; ÖZDEMİR, HALİL; YILMAZ, DİLEK; Sahbudak Bal, Zumrut; Karbuz, Adem; Emiroglu, Melike; Tural Kara, Tugce; BELET, NURŞEN; Kilic, ÖMER; Oncel, Selim; Tanir Basaranoglu, Sevgen; BÜYÜKCAM, AYŞE; Akkoc, Gulsen; SOMER, AYPER; DALGIÇ, Nazan; Demirhan, Salih; ÇELİK, Binnaz; Kaleli, Ilknur; Ersayoglu, Irem; Arslanoglu, Mehmet; Oflu, Ayse; Tufan, Erennur; Ecevit, Ismail; Kurugol, Zafer; DİNLEYİCİ, ENER; TEZER, HASAN; KARA, ATEŞ; ÇİFTCİ, ERGİN

doi:10.1007/s00431-026-07399-z

Pediatric invasive meningococcal disease in Türkiye during the post-pandemic period: increased reported cases and predominance of serogroup B and severity determined by a clinical form in a multicenter hospital-based cohort

Cakmak Taskin E., ARGA G., Arslan B. C., Taskin Karacay I. E., Genceli M., Erdeniz E. H., ...Daha Fazla

European Journal of Pediatrics, cilt.185, sa.10, 2026 (SCI-Expanded, Scopus)

Yayın Türü: Makale / Tam Makale
Cilt numarası: 185 Sayı: 10
Basım Tarihi: 2026
Doi Numarası: 10.1007/s00431-026-07399-z
Dergi Adı: European Journal of Pediatrics
Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, CINAHL, EMBASE, MEDLINE, Academic Search Ultimate (EBSCO), Biomedical Reference Collection: Corporate Edition (EBSCO), Health Research Premium Collection (ProQuest)
Anahtar Kelimeler: Children, COVID-19, Epidemiology, Invasive meningococcal disease, Neisseria meningitidis, Post-pandemic, Serogroup B
Eskişehir Osmangazi Üniversitesi Adresli: Evet

Özet

Invasive meningococcal disease (IMD) remains a major cause of morbidity and mortality in children. Post-pandemic epidemiological patterns of pediatric IMD are not well defined in Türkiye. This study aimed to evaluate the epidemiology, clinical characteristics, outcomes, and serogroup distribution of pediatric IMD in a large multicenter cohort in Türkiye, comparing the during-COVID and post-COVID periods. This retrospective multicenter hospital-based study included children aged 1 month–18 years hospitalized with laboratory-confirmed IMD in 39 hospitals across 23 provinces. Cases were grouped as during-COVID (January 2020–May 2022) and post-COVID (June 2022–December 2025). A total of 166 patients (median age 25 months; 59.6% male) were included; 25 occurred during-COVID and 141 post-COVID. The number of reported cases in participating centers increased after 2022, with seasonal peaks in winter and early spring. Children under 5 years accounted for 62.7% of cases, and infants (< 1 year) were the largest single age group overall (38.6%). The proportion of children under 5 years was lower in the post-COVID period (58.9% vs 84.0%; OR 0.27, 95% CI 0.09–0.84), indicating a relative shift toward older age groups rather than a reduction in disease burden among infants. Pediatric intensive care admission occurred in 69.9% of cases, and overall mortality was 13.3%. Mortality varied markedly by clinical form, from 1.2% in meningitis alone to 21.7% in combined meningitis and meningococcemia and 38.1% in meningococcemia alone (p < 0.001). Only 2.4% of children had received any meningococcal vaccine before their illness. Serogroup data were available for 60.8% of patients, with grouping coverage differing between periods (32.0% vs 66.0%). Among cases with available serogroup data, serogroup B accounted for 69.9% in the post-COVID period and for half of the eight grouped cases during the pandemic. In unadjusted exploratory analysis restricted to cases with serogroup data, mortality was higher in serogroup B than non-B infections (21.7% vs 3.1%; OR 8.61, 95% CI 1.08–68.8); in an exploratory model adjusting for clinical form, age, and period, with ungrouped cases retained as a separate category, serogroup B remained associated with mortality (aOR 7.59, 95% CI 1.55–75.65). Conclusion: In this multicenter hospital-based cohort, reported pediatric IMD cases increased in the post-pandemic period, with a persistent burden in infants, a relative shift toward older age groups, and predominance of serogroup B among grouped cases. These findings highlight the importance of strengthened surveillance and support further evaluation of meningococcal vaccination strategies, including MenB vaccination. (Table presented.)