Multicenter Hospital-Based Prospective Surveillance Study of Bacterial Agents Causing Meningitis and Seroprevalence of Different Serogroups of Neisseria meningitidis, Haemophilus influenzae Type b, and Streptococcus pneumoniae during 2015 to 2018 in Turkey

Abstract

The etiology of bacterial meningitis in Turkey changed after the implementation of conjugated vaccines against Streptococcus pneumoniae and Haemophilus influenzae type b (Hib) in the Turkish National Immunization Program (NIP). Administration of Hib vaccine and PCV-7 (7-valent pneumococcal conjugate vaccine) was implemented in NIP in 2006 and 2009, respectively. In 2011, PCV-7 was replaced with PCV-13. Meningococcal vaccines have not yet been included in Turkish NIP. This prospective study comprised 27 hospitals located in seven regions of Turkey and represented 45% of the population. Children aged between 1 month and 18 years who were hospitalized with suspected meningitis were included. Cerebrospinal fluid (CSF) samples were collected, and bacterial identification was made according to the multiplex PCR assay results. During the study period, 994 children were hospitalized for suspected meningitis, and Hib (n = 3, 2.4%), S. pneumoniae (n = 33, 26.4%), and Neisseria meningitidis (n = 89, 71%) were detected in 125 samples. The most common meningococcal serogroup was MenB. Serogroup W comprised 13.9% (n = 5) and 7.5% (n = 4) of the meningococci in 2015 to 2016 and 2017 to 2018, respectively. Serogroup C was not detected. There were four deaths in the study; one was a pneumococcus case, and the others were serogroup B meningococcus cases. The epidemiology of meningococcal diseases has varied over time in Turkey. Differing from the previous surveillance periods, MenB was the most common serogroup in the 2015-to-2018 period. Meningococcal epidemiology is so dynamic that, for vaccination policies, close monitoring is crucial. IMPORTANCE Acute bacterial meningitis (ABM) is one of the most common life-threatening infections in children. The incidence and prevalence of ABM vary both geographically and temporally; therefore, surveillance systems are necessary to determine the accurate burden of ABM. The Turkish Meningitis Surveillance Group has been performing a hospital-based meningitis surveillance study since 2005 across several regions in Turkey. Meningococcus was the major ABM-causing agent during the 2015-to-2018 period, during which MenB was the dominant serogroup.

Nontraumatic coma in the pediatric intensive care unit: etiology, clinical characteristics and outcome

“…Within the etiological agents of virusassociated encephalitis, we found influenza as the most common causative agent, indicating a resemblance to the study from Japan. In our study, the most common etiology of acute bacterial meningitis was Neisseria meningitides, similar to a multicenter surveillance study from Turkey that reported the same organism as the most frequently encountered cause of acute bacterial meningitis in children [28]. It is interesting that various unusual pathological agents were identified in the study, including Rabies virus, Clostridium tetani and Hydatid cyst.…”

Long Term Impact of Conjugate Vaccines on Haemophilus influenzae Meningitis: Narrative Review

“…Hib meningitis incidence declined by 72–83% at sentinel hospitals in Pakistan and Bangladesh, respectively, within two years of implementing nationwide Hib conjugate vaccination [ 80 ]. In a hospital-based multi-center prospective survey of bacterial meningitis in Turkey from 2015 to 2018, 994 cases of suspected bacterial meningitis in children, aged one month to 18 years, were identified [ 81 ]. Three (2.4%) of the 125 culture-positive cases were caused by Hib.…”

Multicenter prospective surveillance study of viral agents causing meningoencephalitis

“…A drastic change in the aetiology of childhood meningoencephalitis has occurred in Turkey since vaccination programmes have eradicated mumps, measles and rubella associated encephalitides. There is no study involving the national incidence rates of viral meningoencephalitis, except for Ceyhan et al’s studies that have been following bacterial meningitis surveillance nationally for years 5 . We identifed a considerable number of associated agents, nine different viruses in 50 of 186 cases.…”