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).

The COVID19 pandemic has changed women's experiences of pregnancy in the UK (preprint)

Introduction During the SARS-CoV-2 pandemic, maternity care has been substantially altered to reduce transmission of the SARS-CoV-2 virus. Many antenatal services are now restricted or delivered online, and visiting has been restricted during labour and in the postnatal period. Methods We conducted an online survey from 1st August to 31st December 2020 to investigate the experiences of women who were pregnant or breastfeeding in the UK during the SARS-CoV-2 pandemic. The survey included 55 open and closed questions and required 5 minutes to complete. We publicised the survey using social media. Results We received 96 responses, including 66 currently pregnant women and 22 women who were pregnant during the pandemic. The response rate was 70.1% of survey views. We found mixed experiences of the impact of the pandemic on antenatal and perinatal care, notably with some women feeling visiting restrictions were insufficient and others feeling they were too strict. Twenty-nine women received no information about COVID-19, and 6 women found it very difficult to find information. Thirty-nine women would have liked to have more information about breastfeeding after a pregnancy affected by COVID-19, and 37 women wanted more information about antibody persistence and transfer. Discussion Additional support is required for pregnant and lactating women during the current pandemic. Provision of information and support, including via social media, may improve women's experiences of pregnancy in the current environment.

Safety and Immunogenicity Report from the Com-COV Study – a Single-Blind Randomised Non-Inferiority Trial Comparing Heterologous And Homologous Prime-Boost Schedules with An Adenoviral Vectored and mRNA COVID-19 Vaccine (preprint)

Background: Use of heterologous prime-boost COVID-19 vaccine schedules could facilitate mass COVID-19 immunisation, however we have previously reported that heterologous schedules incorporating an adenoviral-vectored vaccine (ChAd, Vaxzevria, Astrazeneca) and an mRNA vaccine (BNT, Comirnaty, Pfizer) at a 4-week interval are more reactogenic than homologous schedules. Here we report the immunogenicity of these schedules. Methods: Com-COV (ISRCTN: 69254139, EudraCT: 2020-005085-33) is a participant-blind, non-inferiority trial evaluating vaccine reactogenicity and immunogenicity. Adults ≥ 50 years, including those with well-controlled comorbidities, were randomised across eight groups to receive ChAd/ChAd, ChAd/BNT, BNT/BNT or BNT/ChAd, administered at 28- or 84-day intervals.The primary endpoint is geometric mean ratio (GMR) of serum SARS-CoV-2 anti-spike IgG levels (ELISA) at one-month post boost between heterologous and homologous schedules given the same prime vaccine. We tested non-inferiority of GMR using a margin of 0.63. The primary analysis was on a per-protocol population, who were seronegative at baseline. Safety analyses were performed amongst participants receiving at least one dose of study vaccines.Findings: In February 2021, 830 participants were enrolled and randomised, including 463 with a 28-day prime-boost interval whose results are reported in this paper. Participant mean age was 57.8 years, 45.8% were female, and 25.3% from ethnic minorities.The geometric mean concentration (GMC) of day 28 post-boost SARS-CoV-2 anti-spike IgG in ChAd/BNT recipients (12,906 ELU/ml) was non-inferior to that in ChAd/ChAd recipients (1,392 ELU/ml) with a geometric mean ratio (GMR) of 9.2 (one-sided 97.5% CI: 7.5, ∞). In participants primed with BNT, we failed to show non-inferiority of the heterologous schedule (BNT/ChAd, GMC 7,133 ELU/ml) against the homologous schedule (BNT/BNT, GMC 14,080 ELU/ml) with a GMR of 0.51 (one-sided 97.5% CI: 0.43, ∞). Geometric mean of T cell response at 28 days post boost in the ChAd/BNT group was 185 SFC/106 PBMCs (spot forming cells/106 peripheral blood mononuclear cells) compared to 50, 80 and 99 SFC/106 PBMCs for ChAd/ChAd, BNT/BNT, and BNT/ChAd, respectively. There were four serious adverse events across all groups, none of which were considered related to immunisation.Interpretation: Despite the BNT/ChAd regimen not meeting non-inferiority criteria, the GMCs of both heterologous schedules were higher than that of a licensed vaccine schedule (ChAd/ChAd) with proven efficacy against COVID-19 disease and hospitalisation. These data support flexibility in the use of heterologous prime-boost vaccination using ChAd and BNT COVID-19 vaccines.Trial Registration: The trial is registered at www.isrctn.com as ISRCTN: 69254139.Funding: Funded by the UK Vaccine Task Force (VTF) and National Institute for Health Research (NIHR)Declaration of Interest: MDS acts on behalf of the University of Oxford as an Investigator on studies funded or sponsored by vaccine manufacturers including AstraZeneca, GlaxoSmithKline, Pfizer, Novavax, Janssen, Medimmune, and MCM vaccines. He receives no personal financial payment for this work. JSN-V-T is seconded to the Department of Health and Social Care, England. AMC and DMF are investigators on studies funded by Pfizer and Unilever. They receive no personal financial payment for this work. AF is a member of the Joint Committee on Vaccination and Immunisation and Chair of the WHO European Technical Advisory Group of Experts (ETAGE) on Immunisation. He is an investigator and/or provides consultative advice on clinical trials and studies of COVID-19 vaccines produced by AstraZeneca, Janssen, Valneva, Pfizer and Sanofi and of other vaccines from these and other manufacturers including GSK, VPI, Takeda and Bionet Asia. He receives no personal remuneration or benefits for any of this work. SNF acts on behalf of University Hospital Southampton NHS Foundation Trust as an Investigator and/or providing consultative advice on clinical trials and studies of COVID-19 and other vaccines funded or sponsored by vaccine manufacturers including Janssen, Pfizer, AstraZeneca, GlaxoSmithKline, Novavax, Seqirus, Sanofi, Medimmune, Merck and Valneva vaccines and antimicrobials. He receives no personal financial payment for this work. PTH acts on behalf of St. George’s University of London as an Investigator on clinical trials of COVID-19 vaccines funded or sponsored by vaccine manufacturers including Janssen, Pfizer, AstraZeneca, Novavax and Valneva. He receives no personal financial payment for this work. CAG acts on behalf of University Hospitals Birmingham NHS Foundation Trust as an Investigator on clinical trials and studies of COVID-19 and other vaccines funded or sponsored by vaccine manufacturers including Janssen, Pfizer, AstraZeneca, Novavax, CureVac, Moderna, and Valneva vaccines, and receives no personal financial payment for this work. VL acts on behalf of University College London Hospitals NHS Foundation Trust as an Investigator on clinical trials of COVID-19 vaccines funded or sponsored by vaccine manufacturers including Pfizer, AstraZeneca and Valneva. He receives no personal financial payment for this work. TL is named as an inventor on a patent application covering this SARS-CoV-2 vaccine and is an occasional consultant to Vaccitech unrelated to this work. Oxford University has entered into a partnership with AstraZeneca for further development of ChAdOx1 nCoV-19Ethical Approval: The trial was reviewed and approved by the South-Central Berkshire Research Ethics Committee (21/SC/0022), the University of Oxford, and the Medicines and Healthcare Products Regulatory Agency MHRA). An independent data safety monitoring board (DSMB) reviewed safety data, and local trial- site physicians provided oversight of all adverse events in real-time.

Safety, Immunogenicity, and Efficacy of a COVID-19 Vaccine (NVX-CoV2373) Co-administered With Seasonal Influenza Vaccines (preprint)

Background The safety and immunogenicity profile of COVID-19 vaccines when administered concomitantly with seasonal influenza vaccines has not yet been reported. Methods A sub-study on influenza vaccine co-administration was conducted as part of the phase 3 randomized trial of the safety and efficacy of NVX-CoV2373. The first ~400 participants meeting main study entry criteria and with no contraindications to influenza vaccination were invited to join the sub-study. After randomization in a 1:1 ratio to receive NVX-CoV2373 (n=217) or placebo (n=214), sub-study participants received an age-appropriate, licensed, open-label influenza vaccine with dose 1 of NVX-CoV2373. Reactogenicity was evaluated via electronic diary for 7 days post-vaccination in addition to monitoring for unsolicited adverse events (AEs), medically-attended AEs (MAAEs), and serious AEs (SAEs). Influenza haemagglutination inhibition and SARS-CoV-2 anti-spike IgG assays were performed. Vaccine efficacy against PCR-confirmed, symptomatic COVID-19 was assessed. Comparisons were made between sub-study and main study participants. Findings Sub-study participants were younger, more racially diverse, and had fewer comorbid conditions than main study participants. Reactogenicity events more common in the co-administration group included tenderness (70.1% vs 57.6%) or pain (39.7% vs 29.3%) at injection site, fatigue (27.7% vs 19.4%), and muscle pain (28.3% vs 21.4%). Rates of unsolicited AEs, MAAEs, and SAEs were low and balanced between the two groups. Co-administration resulted in no change to influenza vaccine immune response, while a reduction in antibody responses to the NVX-CoV2373 vaccine was noted. Vaccine efficacy in the sub-study was 87.5% (95% CI: -0.2, 98.4) while efficacy in the main study was 89.8% (95% CI: 79.7, 95.5). Interpretation This is the first study to demonstrate the safety, immunogenicity, and efficacy profile of a COVID-19 vaccine when co-administered with seasonal influenza vaccines. The results suggest concomitant vaccination may be a viable immunisation strategy. Funding This study was funded by Novavax, Inc.