Evaluation of immunogenicity and reactogenicity of COVID-19 vaccines in pregnant women.

OBJECTIVE: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in pregnancy is associated with increased risk of adverse maternal and perinatal outcomes. Vaccines are highly effective at preventing severe coronavirus disease 2019 (COVID-19), but there are limited data on COVID-19 vaccines in pregnancy. This study aimed to investigate the reactogenicity and immunogenicity of COVID-19 vaccines in pregnant women when administered according to the 12-week-interval dosing schedule recommended in the UK. METHODS: This was a cohort study of pregnant women receiving COVID-19 vaccination between April and September 2021. The outcomes were immunogenicity and reactogenicity after COVID-19 vaccination. Pregnant women were recruited by phone, e-mail and/or text and were vaccinated according to vaccine availability at their local vaccination center. For immunogenicity assessment, blood samples were taken at specific timepoints after each dose to evaluate nucleocapsid protein (N) and spike protein (S) antibody titers. The comparator group comprised non-pregnant female healthcare workers in the same age group who were vaccinated as part of the national immunization program in a contemporaneous longitudinal cohort study. Longitudinal changes in serum antibody titers and association with pregnancy status were assessed using a two-step regression approach. Reactogenicity assessment in pregnant women was undertaken using an online questionnaire. The comparator group comprised non-pregnant women aged 18-49 years who had received two vaccine doses in primary care. The association of pregnancy status with reactogenicity was assessed using logistic regression analysis. RESULTS: Overall, 67 pregnant women, of whom 66 had received a mRNA vaccine, and 79 non-pregnant women, of whom 50 had received a mRNA vaccine, were included in the immunogenicity study. Most (61.2%) pregnant women received their first vaccine dose in the third trimester, while 3.0% received it in the first trimester and 35.8% in the second trimester. SARS-CoV-2 S-antibody geometric mean concentrations after mRNA vaccination were not significantly different at 2-6 weeks after the first dose but were significantly lower at 2-6 weeks after the second dose in infection-naïve pregnant compared with non-pregnant women. In pregnant women, prior infection was associated with higher antibody levels at 2-6 weeks after the second vaccine dose. Reactogenicity analysis included 108 pregnant women and 116 non-pregnant women. After the first dose, tiredness and chills were reported less commonly in pregnant compared with non-pregnant women (P = 0.043 and P = 0.029, respectively). After the second dose, feeling generally unwell was reported less commonly (P = 0.046) in pregnant compared with non-pregnant women. CONCLUSIONS: Using an extended 12-week interval between vaccine doses, antibody responses after two doses of mRNA COVID-19 vaccine were found to be lower in pregnant compared with non-pregnant women. Strong antibody responses were achieved after one dose in previously infected women, regardless of pregnancy status. Pregnant women reported fewer adverse events after both the first and second dose of vaccine. These findings should now be addressed in larger controlled studies. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Surveillance of congenital Zika syndrome in England and Wales: methods and results of laboratory, obstetric and paediatric surveillance.

The spread of the Zika virus (ZIKV) in the Americas led to large outbreaks across the region and most of the Southern hemisphere. Of greatest concern were complications following acute infection during pregnancy. At the beginning of the outbreak, the risk to unborn babies and their clinical presentation was unclear. This report describes the methods and results of the UK surveillance response to assess the risk of ZIKV to children born to returning travellers. Established surveillance systems operating within the UK - the paediatric and obstetric surveillance units for rare diseases, and national laboratory monitoring - enabled rapid assessment of this emerging public health threat. A combined total of 11 women experiencing adverse pregnancy outcomes after possible ZIKV exposure were reported by the three surveillance systems; five miscarriages, two intrauterine deaths and four children with clinical presentations potentially associated with ZIKV infection. Sixteen women were diagnosed with ZIKV during pregnancy in the UK. Amongst the offspring of these women, there was unequivocal laboratory evidence of infection in only one child. In the UK, the number and risk of congenital ZIKV infection for travellers returning from ZIKV-affected countries is very small.

The United Kingdom Primary Immune Deficiency (UKPID) Registry: report of the first 4 years' activity 2008-2012.

This report summarizes the establishment of the first national online registry of primary immune deficency in the United Kingdom, the United Kingdom Primary Immunodeficiency (UKPID Registry). This UKPID Registry is based on the European Society for Immune Deficiency (ESID) registry platform, hosted on servers at the Royal Free site of University College, London. It is accessible to users through the website of the United Kingdom Primary Immunodeficiency Network (www.ukpin.org.uk). Twenty-seven centres in the United Kingdom are actively contributing data, with an additional nine centres completing their ethical and governance approvals to participate. This indicates that 36 of 38 (95%) of recognized centres in the United Kingdom have engaged with this project. To date, 2229 patients have been enrolled, with a notable increasing rate of recruitment in the past 12 months. Data are presented on the range of diagnoses recorded, estimated minimum disease prevalence, geographical distribution of patients across the United Kingdom, age at presentation, diagnostic delay, treatment modalities used and evidence of their monitoring and effectiveness.

The changing antibiotic susceptibility of bloodstream infections in the first month of life: informing antibiotic policies for early- and late-onset neonatal sepsis.

This study describes the association between antibiotic resistance of bacteria causing neonatal bloodstream infection (BSI) and neonatal age to inform empirical antibiotic treatment guidelines. Antibiotic resistance data were analysed for 14 078 laboratory reports of bacteraemia in neonates aged 0-28 days, received by the Health Protection Agency's (now Public Health England) voluntary surveillance scheme for England and Wales between January 2005 and December 2010. Linear and restricted cubic splines were used in logistic regression models to estimate the nonlinear relationship between age and resistance; the significance of confounding variables was assessed using likelihood ratio tests. An increase in resistance in bacteria causing BSI in neonates aged <4 days was observed, which was greatest between days 2-3 and identified an age (4-8 days, depending on the antibiotic) at which antibiotic resistance plateaus to almost unchanging levels. Our results indicate important age-associated changes in antibiotic resistance and support current empirical treatment guidelines.

Paediatric meningitis in the conjugate vaccine era and a novel clinical decision model to predict bacterial aetiology.

OBJECTIVES: 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, and prospectively recruited at 31 UK hospitals. Meningitis was defined as identification of bacteria/viruses from cerebrospinal fluid (CSF) and/or a raised CSF white blood cell count. New clinical decision rules were developed to distinguish bacterial from viral meningitis and those of alternative aetiology. RESULTS: The cohort included 3002 children (median age 2·4 months); 1101/3002 (36·7%) had meningitis, including 180 bacterial, 423 viral and 280 with no pathogen identified. Enterovirus was the most common pathogen in those aged <6 months and 10-16 years, with Neisseria meningitidis and/or Streptococcus pneumoniae commonest at age 6 months to 9 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 lumbar puncture (sensitivity 84%, specificity 93%), to determine risk of bacterial meningitis. CONCLUSIONS: Bacterial meningitis comprised 6% of children with suspected meningitis/encephalitis. Our clinical decision rules provide potential novel approaches to assist with identifying children with bacterial meningitis. FUNDING: This study was funded by the Meningitis Research Foundation, Pfizer and the NIHR Programme Grants for Applied Research.

Joint consensus statement on the vaccination of adult and paediatric haematopoietic stem cell transplant recipients: Prepared on behalf of the British society of blood and marrow transplantation and cellular therapy (BSBMTCT), the Children's cancer and Leukaemia Group (CCLG), and British Infection Association (BIA).

Haematopoietic stem cell transplant (HSCT) recipients have deficiencies in their adaptive immunity against vaccine preventable diseases. National and International guidance recommends that HSCT recipients are considered 'never vaccinated' and offered a comprehensive course of revaccination. This position statement aims to draw upon the current evidence base and existing guidelines, and align this with national vaccine availability and licensing considerations in order to recommend a pragmatic and standardised re-vaccination schedule for adult and paediatric HSCT recipients in the UK.

Variation in gentamicin and vancomycin dosage and monitoring in UK neonatal units.

BACKGROUND: Gentamicin and vancomycin are commonly used in neonatal units for the treatment of life-threatening infections. This study aimed to describe the dosage regimen and the approach to therapeutic drug monitoring (TDM) for both antibiotics in units that participate in a UK neonatal network. METHODS: Questionnaires were sent to all units across the Extended Neonatal Network, requesting details of each unit's dosing regimen and TDM practice. RESULTS: A total of 43 (of 114) units replied to the gentamicin questionnaire and 29 to the vancomycin questionnaire. Ten different gentamicin dosing regimens were used, depending on gestational age and weight. Most units (79%) followed British National Formulary for Children dosing guidance regarding vancomycin, but there were nine variations in TDM practice. CONCLUSIONS: There is significant variation in gentamicin and vancomycin dosing regimens and TDM guidance across a UK network of neonatal units. The development of standardized, evidence-based protocols should be prioritized.

Pneumococcal conjugate vaccines. A review.

The pneumococcus is currently the most common cause of vaccine-preventable death in children aged less than 5 years, and in 2002 was responsible for 716,000 deaths worldwide. Treatment with antibiotics was the main approach to contain the pneumococcus, however, even with effective antibiotics, pneumococcal meningitis has a poor prognosis and with the emergence of drug resistant pneumococcal disease the need for prevention by vaccine was evident. The first born pneumococcal vaccines were polysaccharide vaccines that unfortunately did not protect young children. The most vulnerable age group of children, less than 2 years of age, were without any form of protection from the pneumococcus until the licensure of a conjugate vaccine. Conjugation of bacteria polysaccharides to carrier proteins has been a significant milestone in the work of vaccine development and has been previously used successfully in the production of the Haemophilus influenzae-print type b vaccine. The seven-valent pneumococcal conjugate vaccine was first licensed in the USA in 2000 and in the European Union this conjugate vaccine was licensed in February 2001. Currently, fourteen countries have included this vaccine in their immunization programmes. Vaccination policies are found to differ greatly across Europe due to differences in local epidemiological situation, and also due to economic considerations. However, many countries are reviewing their own policies based on available data on the burden of pneumococcal disease. This review aims to give an overview about the pneumococcus, the development of the pneumococcal conjugate vaccine, and its impact.

Conjugate vaccines for preventing meningococcal C meningitis and septicaemia.

BACKGROUND: Meningococcal polysaccharide (MPLS) vaccines protect against Serogroup C disease, but do not produce an immune response in infants less than two years of age. This limitation can be overcome by linking C polysaccharide to carrier proteins ('conjugating'), to create meningococcal serogroup C conjugate (MCC) vaccines. In the absence of trial data, the immune response to vaccination has been considered to be a reasonable surrogate for vaccine protection. OBJECTIVES: To assess the immunogenicity, safety and efficacy of MCC vaccines for preventing meningitis and septicaemia. SEARCH STRATEGY: We searched the Cochrane Central Register Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2005); MEDLINE (1966 to September, Week 1 2005); and EMBASE (1990 to June 2005) and references of studies. SELECTION CRITERIA: Randomised controlled trials (RCTs) and controlled clinical trials (CCTs) in humans comparing MCC vaccines against a control vaccine or none. In the absence of any trials on vaccine efficacy, population-based observational studies about effectiveness were included. DATA COLLECTION AND ANALYSIS: Two authors independently screened the results of the literature searches, selected eligible studies, extracted the data and evaluated the quality of them. MAIN RESULTS: The studies showed that MCC vaccine was highly immunogenic in infants after two and three doses, in toddlers after one and two doses and in older age groups after one dose. In general higher titres were generated after MCC than after MPLS vaccines. Immunological hypo-responsiveness seen after repeated doses of MPLS vaccine may be overcome with MCC. Observational studies have documented a significant decline in meningococcal C disease in countries where MCC vaccines have been widely used. The timing of the vaccinations schedules, the specific conjugate used, and the vaccines given concomitantly or combined, may be important. AUTHORS' CONCLUSIONS: The MCC vaccine appears to be safe, immunogenic and able to induce immunological memory in all age groups. Observational studies strongly suggest that MCC is clinically effective.

Lack of evidence for the efficacy of enhanced surveillance compared to other specific interventions to control neonatal healthcare-associated infection outbreaks.

BACKGROUND: Despite current prevention efforts, outbreaks of healthcare-associated infections in neonatal units remain high globally, with a considerable burden of mortality and morbidity. METHODS: We searched Medline, Cochrane Library and Outbreak database to identify studies of neonatal healthcare-associated outbreaks between 2005 and 2015 that described interventions to control outbreaks. All studies were evaluated using the ORION guidance. RESULTS: Thirty studies were identified including 17 102 infants of whom 664 (3.9%) became infected. No single intervention was identified that reduced duration or mortality. Studies that introduced multiple interventions had significantly reduced case fatality ratio and outbreak duration compared to those that used basic surveillance only. Low and low-middle income countries reported the fewest interventions to control outbreaks and these studies were also associated with higher mortality than that found in middle and high income countries. CONCLUSIONS: Systematic reporting and formal evaluation of interventions used to reduce healthcare-associated neonatal infection outbreaks is key to identifying containment strategies worldwide.

Risk factors for Group B Streptococcus colonisation and disease in Gambian women and their infants.

OBJECTIVES: To determine risk factors for GBS colonisation in Gambian mothers and in their infants from birth to day 60-89 of age. METHODS: Swabs and breastmilk from mothers/infant pairs were collected and cultured on selective agar. Negative samples were analysed for GBS DNA via real-time PCR. Positive isolates were serotyped using multiplex PCR and gel-agarose electrophoresis. RESULTS: Seven hundred and fifty women/infant pairs were recruited. 253 women (33.7%) were GBS-colonised at delivery. The predominant serotypes were: V (55%), II (16%), III (10%), Ia (8%) and Ib (8%). 186 infants were colonised (24.8%) at birth, 181 (24.1%) at 6 days and 96 at day 60-89 (14%). Infants born before 34 weeks of gestation and to women with rectovaginal and breastmilk colonisation at delivery had increased odds of GBS colonisation at birth. Season of birth was associated with increased odds of persistent infant GBS colonisation (dry season vs. wet season AOR 2.9; 95% CI 1.6-5.2). CONCLUSION: GBS colonisation is common in Gambian women at delivery and in their infants to day 60-89 and is dominated by serotype V. In addition to maternal colonisation, breastmilk and season of birth are important risk factors for infant GBS colonisation.

Neonatal sepsis: an international perspective.

Neonatal infections currently cause about 1.6 million deaths annually in developing countries. Sepsis and meningitis are responsible for most of these deaths. Resistance to commonly used antibiotics is emerging and constitutes an important problem world wide. To reduce global neonatal mortality, strategies of proven efficacy, such as hand washing, barrier nursing, restriction of antibiotic use, and rationalisation of admission to neonatal units, need to be implemented. Different approaches require further research.

Haemophilus influenzae type b conjugate vaccines: a review of efficacy data.

BACKGROUND: The development of a vaccine against Haemophilus influenzae type b (Hib) was stimulated by its recognition as a major pathogen of early childhood. The first vaccine to be developed was composed of the capsular polysaccharide of the organism, polyribosylribitol phosphate (PRP), and although effective in older children, it failed to protect those <2 years of age, the group with the highest burden of disease. The conjugation of PRP to protein led to a group of vaccines with enhanced immunogenicity and the ability to induce immunologic memory and thus the potential to protect in infancy. OBJECTIVES: To review the trials of Hib conjugate vaccines in which protective efficacy in infants has been assessed and the experience in countries in which Hib conjugate vaccines have been introduced into the routine infant immunization schedule. DISCUSSION: Each of the Hib conjugate vaccines [PRP-diphtheria toxoid conjugate (PRP-D), PRP conjugated to outer membrane protein of Neisseria meningitidis group B (PRP-OMP), PRP oligosaccharides conjugated to mutant diphtheria toxin CRM197, (HbOC) and PRP conjugated to tetanus toxoid (PRP-T)] has been subjected to prospective clinical trials and all have demonstrated high protective efficacy with one exception: that of the least immunogenic vaccine, PRP-D, when used in a Native American population with a high level of natural disease. The trials have used different populations and different schedules, which limits conclusions about relative efficacies. However, it seems likely that all the vaccines are capable of high efficacy in populations with low levels and late age of Hib disease. Three vaccines (PRP-D, PRP-OMP, PRP-T) have been tested in populations with high rates of disease and only PRP-D has been found lacking. As predicted by immunogenicity data, PRP-OMP affords efficacy after one dose, and PRP-T is efficacious with an accelerated schedule. Of more practical significance the effectiveness of these vaccines when introduced into populations has been uniformly impressive. CONCLUSIONS: Particularly where vaccine coverage is high, it is now likely that Hib disease can be eliminated using Hib conjugate vaccines in infancy.

Non-type b Haemophilus influenzae disease: clinical and epidemiologic characteristics in the Haemophilus influenzae type b vaccine era.

BACKGROUND: As a result of the decline in Haemophilus influenzae type b (Hib) disease caused by the widespread use of conjugate vaccines, non-type b H. influenzae will become a more important cause of H. influenzae (Hi) disease. Characterization of the clinical and epidemiologic features of non-b Hi disease is needed in the Hib vaccine era. METHODS: A prospective active surveillance study of invasive Hi disease involving pediatricians in the United Kingdom and Republic of Ireland. For the first phase of the study (October 1, 1992, to October 31, 1995) pediatricians were asked to report any child who had invasive Hi disease and who had received Hib conjugate vaccine. For the second phase of the study (November 1, 1995. To December 31, 1998) pediatricians were asked to report any child with invasive Hi disease regardless of vaccination status. RESULTS: During the study period 102 cases of invasive non-type b Hi disease and 106 cases of invasive Hib disease were reported in children who had been fully vaccinated against Hib. Children with non-type b disease were younger (16 vs. 22 months of age, P = 0.08), less likely to have meningitis and epiglottitis (P < or = 0.001) and more likely to have pneumonia and bacteremia (P < or = 0.001) than children with type b disease. For the last 2 years of the study invasive Hi disease occurring in a fully vaccinated child was more likely to be caused by a non-b strain than by a type b strain (58 vs. 38). In 1998 the incidence of non type-b Hi disease in all children <5 years of age in the UK was 1.3/100,000 as compared with an incidence of Hib disease of 0.6/100,000. The majority (88%) of non-b strains isolated in children were nontypable strains. CONCLUSIONS: Non-b Hi is a rare cause of disease in children, but in the Hib vaccine era it has become more common than type b as a cause of Hi disease in fully vaccinated children.

Neonatal meningitis.

Twelve years ago an annotation was published in Archives of Disease in Childhood regarding the antibiotic treatment of suspected neonatal meningitis. The authors recommended the use of cephalosporins rather than chloramphenicol and advocated intraventricular aminoglycoside treatment in selected cases. They noted the absence of clinical trials with third generation cephalosporins that showed an improvement in mortality or neurological outcome.

Early onset group B streptococcal neonatal infection in Oxford 1985-96.

Of 74,920 babies live born in Oxford between 1985 and 1996, 41 (0.5 per 1000 95% CI 0.4-0.7) developed definite, culture confirmed, early onset (< 48 hours) group B streptococcal infection and 32 (0.4 per 1000 95% CI 0.3-0.6) developed probable infection (sepsis plus colonisation). There was no significant variation in incidence with time. The mortality from definite infection was 19.5%, and from probable infection 6%. These data suggest that the incidence of group B streptococcal infection in Oxford is considerably lower than that reported in the USA.

Pneumococcal disease in childhood.

Streptococcus pneumoniae is the most common cause of serious bacterial infections in children worldwide. Problems with antibiotic resistance have lead to changes in antibiotic policies for children with possible pneumococcal disease. Demonstration of the efficacy of a pneumococcal conjugate vaccine has lead to consideration of its inclusion in routine infant vaccination schedules.