Paediatric Meningitis in the Conjugate Vaccine Era and Development of a Novel Clinical Decision Model to Predict Bacterial Aetiology in 3,002 Children with Suspected Meningitis (preprint)

Background: Implementation of bacterial conjugate vaccines have resulted in dramatic reductions in bacterial meningitis globally. The aetiology of childhood meningitis in the conjugate vaccine era is not well-defined, and differentiating bacterial meningitis from other similar childhood illnesses is a major challenge. The aims of this study were to assess aetiology and clinical characteristics in childhood meningitis, and develop clinical decision rules to distinguish bacterial meningitis from other similar clinical syndromes.Methods: Children aged <16 years hospitalised with suspected meningitis/encephalitis were included. Meningitis was defined as identification of bacteria/viruses from CSF and/or a CSF WBC>5/μL. Aetiology and clinical and laboratory features were analysed. Two new clinical decision rules were developed to distinguish bacterial meningitis from aseptic or suspected meningitis.Findings: 3,002 children (median age 2·4 months, IQR: 1·0-12·7) were prospectively recruited at 31 UK hospitals. Overall 1,101/3,002 (36·7%) had meningitis, including 203 with a bacterial aetiology, 423 viral and 280 with no pathogen identified. Enterovirus was the most common pathogen in those aged < six months and 10-16 years, with N. meningitidis and/or S. pneumoniae commonest at age six months–nine years. The Bacterial Meningitis Score had a negative predictive value of 95·3%. We developed two clinical decision rules, that could be used either before (sensitivity 82%, specificity 71%) or after LP (sensitivity 84%, specificity 93%), to determine risk of bacterial meningitis.Interpretation: Bacterial meningitis comprised only 6% of children presenting to hospital with suspected meningitis/encephalitis. Our clinical decision rules provide important novel approaches to identify the children with bacterial meningitis.Funding: This independent research was supported by the UK Meningitis Research Foundation, Pfizer, and the National Institute for Health Research Programme Grants for Applied Research Programme (Understanding and improving the outcome of viral encephalitis, RP-PG-0108- 10048). MS is supported via salary awards from the BC Children’s Hospital Foundation and Michael Smith Health Research BC. TS is supported by the National Institute for Health and Care Research (NIHR) Health Protection Research Unit in Emerging and Zoonotic Infections (Grant Nos. IS-HPU- 1112-10117 and NIHR200907).Declaration of Interest: MS has been an investigator on projects funded by GlaxoSmithKline, Merck, Moderna, Pfizer, Sanofi-Pasteur, Seqirus, Symvivo and VBI Vaccines. All funds have been paid to his institute, and he has not received any personal payments. AJP was a member of the World Health Organization’s Strategic Advisory Group of Experts on Immunization until January 2022 and remains chair of the UK Department of Health and Social Care's Joint Committee on Vaccination and Immunisation (JCVI). AJP also reports providing advice to Shionogi on COVID-19, and funding from the National Institute for Health Research (NIHR), AstraZeneca, the Bill & Melinda Gates Foundation, Wellcome, the Medical Research Council, and the Coalition for Epidemic Preparedness Innovations (CEPI). Oxford University has entered into a partnership with AstraZeneca for the development of COVID-19 vaccines. TS is Director of The Pandemic Institute, which has received funding from Innova, CSL Seqirus, Aviva and DAM Health; was an advisor to the GSK Ebola Vaccine programme and the Siemens Diagnostic Programme; Co-Chaired the WHO Neuro-COVID task force and sat on the UK Government’s Advisory Committee on Dangerous Pathogens, and the Medicines and Healthcare Products Regulatory Agency (MHRA) Expert Working Group on Covid-19 vaccines. PH has been an investigator on projects funded by GlaxoSmithKline, Merck, Moderna, Pfizer, Sanofi- Pasteur, Novavax, Valneva, Minervax and AZ. All funds have been paid to his institute, and he has not received any personal payments. He is a member of the UK JCVI. All other authors have no COI to disclose.Ethical Approval: The study was approved by NRES Committee East Midlands - Nottingham 1 (Ref: 11/EM/0442).

Prevalence of Urinary Tract Infection, Bacteremia, and Meningitis Among Febrile Infants Aged 8 to 60 Days With SARS-CoV-2.

Importance: The prevalence of urinary tract infection (UTI), bacteremia, and bacterial meningitis in febrile infants with SARS-CoV-2 is largely unknown. Knowledge of the prevalence of these bacterial infections among febrile infants with SARS-CoV-2 can inform clinical decision-making. Objective: To describe the prevalence of UTI, bacteremia, and bacterial meningitis among febrile infants aged 8 to 60 days with SARS-CoV-2 vs without SARS-CoV-2. Design, Setting, and Participants: This multicenter cross-sectional study was conducted as part of a quality improvement initiative at 106 hospitals in the US and Canada. Participants included full-term, previously healthy, well-appearing infants aged 8 to 60 days without bronchiolitis and with a temperature of at least 38 °C who underwent SARS-CoV-2 testing in the emergency department or hospital between November 1, 2020, and October 31, 2022. Statistical analysis was performed from September 2022 to March 2023. Exposures: SARS-CoV-2 positivity and, for SARS-CoV-2-positive infants, the presence of normal vs abnormal inflammatory marker (IM) levels. Main Outcomes and Measures: Outcomes were ascertained by medical record review and included the prevalence of UTI, bacteremia without meningitis, and bacterial meningitis. The proportion of infants who were SARS-CoV-2 positive vs negative was calculated for each infection type, and stratified by age group and normal vs abnormal IMs. Results: Among 14 402 febrile infants with SARS-CoV-2 testing, 8413 (58.4%) were aged 29 to 60 days; 8143 (56.5%) were male; and 3753 (26.1%) tested positive. Compared with infants who tested negative, a lower proportion of infants who tested positive for SARS-CoV-2 had UTI (0.8% [95% CI, 0.5%-1.1%]) vs 7.6% [95% CI, 7.1%-8.1%]), bacteremia without meningitis (0.2% [95% CI, 0.1%-0.3%] vs 2.1% [95% CI, 1.8%-2.4%]), and bacterial meningitis (<0.1% [95% CI, 0%-0.2%] vs 0.5% [95% CI, 0.4%-0.6%]). Among infants aged 29 to 60 days who tested positive for SARS-CoV-2, 0.4% (95% CI, 0.2%-0.7%) had UTI, less than 0.1% (95% CI, 0%-0.2%) had bacteremia, and less than 0.1% (95% CI, 0%-0.1%) had meningitis. Among SARS-CoV-2-positive infants, a lower proportion of those with normal IMs had bacteremia and/or bacterial meningitis compared with those with abnormal IMs (<0.1% [0%-0.2%] vs 1.8% [0.6%-3.1%]). Conclusions and Relevance: The prevalence of UTI, bacteremia, and bacterial meningitis was lower for febrile infants who tested positive for SARS-CoV-2, particularly infants aged 29 to 60 days and those with normal IMs. These findings may help inform management of certain febrile infants who test positive for SARS-CoV-2.

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 (rs = -0.430, P = 0.036), H. influenzae (rs = -0.922, P < 0.001), while trend toward an increase in the relative proportion of S. aureus (rs = 0.850, P < 0.001), S. agalactiae (rs = 0.615, P = 0.001), and S. pyogenes (rs = 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.

Trends in Prevalence of Bacterial Infections in Febrile Infants During the COVID-19 Pandemic.

OBJECTIVES: Our objective was to describe the prevalence of urinary tract infection (UTI) and invasive bacterial infection (IBI) in febrile infants during the coronavirus disease 2019 pandemic. METHODS: We conducted a multicenter cross-sectional study that included 97 hospitals in the United States and Canada. We included full-term, well-appearing infants 8 to 60 days old with a temperature of ≥38°C and an emergency department visit or hospitalization at a participating site between November 1, 2020 and March 31, 2022. We used logistic regression to determine trends in the odds of an infant having UTI and IBI by study month and to determine the association of COVID-19 prevalence with the odds of an infant having UTI and IBI. RESULTS: We included 9112 infants; 603 (6.6%) had UTI, 163 (1.8%) had bacteremia without meningitis, and 43 (0.5%) had bacterial meningitis. UTI prevalence decreased from 11.2% in November 2020 to 3.0% in January 2022. IBI prevalence was highest in February 2021 (6.1%) and decreased to 0.4% in January 2022. There was a significant downward monthly trend for odds of UTI (odds ratio [OR] 0.93; 95% confidence interval [CI]: 0.91-0.94) and IBI (OR 0.90; 95% CI: 0.87-0.93). For every 5% increase in COVID-19 prevalence in the month of presentation, the odds of an infant having UTI (OR 0.97; 95% CI: 0.96-0.98) or bacteremia without meningitis decreased (OR 0.94; 95% CI: 0.88-0.99). CONCLUSIONS: The prevalence of UTI and IBI in eligible febrile infants decreased to previously published, prepandemic levels by early 2022. Higher monthly COVID-19 prevalence was associated with lower odds of UTI and bacteremia.

3' Tth Endonuclease Cleavage Polymerase Chain Reaction (3TEC-PCR) Technology for Single-Base-Specific Multiplex Pathogen Detection using a Two-Oligonucleotide System.

Polymerase chain reaction (PCR) is the standard in nucleic acid amplification technology for infectious disease pathogen detection and has been the primary diagnostic tool employed during the global COVID-19 pandemic. Various PCR technology adaptations, typically using two-oligonucleotide dye-binding methods or three-oligonucleotide hydrolysis probe systems, enable real-time multiplex target detection or single-base specificity for the identification of single-nucleotide polymorphisms (SNPs). A small number of two-oligonucleotide PCR systems facilitating both multiplex detection and SNP identification have been reported; however, these methods often have limitations in terms of target specificity, production of variable or false-positive results, and the requirement for extensive optimisation or post-amplification analysis. This study introduces 3' Tth endonuclease cleavage PCR (3TEC-PCR), a two-oligonucleotide PCR system incorporating a modified primer/probe and a thermostable cleavage enzyme, Tth endonuclease IV, for real-time multiplex detection and SNP identification. Complete analytical specificity, low limits of detection, single-base specificity, and simultaneous multiple target detection have been demonstrated in this study using 3TEC-PCR to identify bacterial meningitis associated pathogens. This is the first report of a two-oligonucleotide, real-time multiplex PCR technology with single-base specificity using Tth endonuclease IV.

Austrian syndrome, ceftriaxone-induced agranulocytosis and COVID-19.

We present a case of a 75-year-old woman with Austrian syndrome: pneumonia, meningitis and endocarditis all due to Streptococcus pneumoniae Transoesophageal echocardiogram demonstrated a large mitral valve vegetation with severe mitral regurgitation. She was treated with intravenous ceftriaxone and listed for surgical repair of her mitral valve. Preoperatively, she developed an idiosyncratic drug-induced agranulocytosis secondary to ceftriaxone, which resolved on cessation of the medication. However, while awaiting neutrophil recovery, she developed an acute deterioration, becoming critically unwell. This deterioration was multifactorial, with acute decompensated heart failure alongside COVID-19. After multidisciplinary discussion, she was considered too unwell for surgery and palliated.

Purinergic signaling in infectious diseases of the central nervous system.

The incidence of infectious diseases affecting the central nervous system (CNS) has been increasing over the last several years. Among the reasons for the expansion of these diseases and the appearance of new neuropathogens are globalization, global warming, and the increased proximity between humans and wild animals due to human activities such as deforestation. Neurotropism affecting normal brain function is shared by organisms such as viruses, bacteria, fungi, and parasites. Neuroinfections caused by these agents activate immune responses, inducing neuroinflammation, excitotoxicity, and neurodegeneration. Purinergic signaling is an evolutionarily conserved signaling pathway associated with these neuropathologies. During neuroinfections, host cells release ATP as an extracellular danger signal with pro-inflammatory activities. ATP is metabolized to its derivatives by ectonucleotidases such as CD39 and CD73; ATP and its metabolites modulate neuronal and immune mechanisms through P1 and P2 purinergic receptors that are involved in pathophysiological mechanisms of neuroinfections. In this review we discuss the beneficial or deleterious effects of various components of the purinergic signaling pathway in infectious diseases that affect the CNS, including human immunodeficiency virus (HIV-1) infection, herpes simplex virus type 1 (HSV-1) infection, bacterial meningitis, sepsis, cryptococcosis, toxoplasmosis, and malaria. We also provide a description of this signaling pathway in emerging viral infections with neurological implications such as Zika and SARS-CoV-2.