Modified multiple marker aneuploidy screening as a primary screening test for preeclampsia.

BACKGROUND: Abnormal levels of maternal biochemical markers used in multiple marker aneuploidy screening have been associated with adverse pregnancy outcomes. This study aims to assess if a combination of maternal characteristics and biochemical markers in the first and second trimesters can be used to screen for preeclampsia (PE). The secondary aim was to assess this combination in identifying pregnancies at risk for gestational hypertension and preterm birth. METHODS: This case-control study used information on maternal characteristics and residual blood samples from pregnant women who have undergone multiple marker aneuploidy screening. The median multiple of the median (MoM) of first and second trimester biochemical markers in cases (women with PE, gestational hypertension and preterm birth) and controls were compared. Biochemical markers included pregnancy-associated plasma protein A (PAPP-A), placental growth factor (PlGF), human chorionic gonadotropin (hCG), alpha feto-protein (AFP), unconjugated estriol (uE3) and Inhibin A. Logistic regression analysis was used to estimate screening performance using different marker combinations. Screening performance was defined as detection rate (DR) and false positive rate (FPR). Preterm and early-onset preeclampsia PE were defined as women with PE who delivered at < 37 and < 34 weeks of gestation, respectively. RESULTS: There were 147 pregnancies with PE (81 term, 49 preterm and 17 early-onset), 295 with gestational hypertension, and 166 preterm birth. Compared to controls, PE cases had significantly lower median MoM of PAPP-A (0.77 vs 1.10, p < 0.0001), PlGF (0.76 vs 1.01, p < 0.0001) and free-ß hCG (0.81 vs. 0.98, p < 0.001) in the first trimester along with PAPP-A (0.82 vs 0.99, p < 0.01) and PlGF (0.75 vs 1.02, p < 0.0001) in the second trimester. The lowest first trimester PAPP-A, PlGF and free ß-hCG were seen in those with preterm and early-onset PE. At a 20% FPR, 67% of preterm and 76% of early-onset PE cases can be predicted using a combination of maternal characteristics with PAPP-A and PlGF in the first trimester. The corresponding DR was 58% for gestational hypertension and 36% for preterm birth cases. CONCLUSIONS: Maternal characteristics with first trimester PAPP-A and PlGF measured for aneuploidy screening provided reasonable accuracy in identifying women at risk of developing early onset PE, allowing triage of high-risk women for further investigation and risk-reducing therapy. This combination was less accurate in predicting women who have gestational hypertension or preterm birth.

Parental Perceptions Regarding the Impact of Housing on Child Health.

Introduction Childhood poverty has life-long adverse impacts. We aimed to assess perceptions of parents of a cohort of children attending a paediatric emergency department regarding the impact of their housing on their child and family Methods From 01/11/2020 - 08/01/2021 a cross-sectional study was performed in a paediatric emergency department in Dublin Results Of 312 parents who completed a questionnaire, 4.5% (n = 14) reported themselves to be homeless. Homeless children were less likely to be registered with general practitioners (78.6% vs. 97.5%, p = .009) or be fully vaccinated (71.4% vs. 92.4%, p = .024). Homeless parents were more likely to feel unsafe at home (35.7% vs. 3.4%, p <.001), and to report that their housing negatively impacted their child's education (58.3% vs 10.7%, p <.001), physical health (45.5% vs 11.7, p = .007), and mental health (61.5% vs 12.6%, p <.001). Ten percent of non-homeless parents were concerned about losing their home. A lack of landlord permission to install child safety measures in the home was reported by 28% of all parents. Conclusion Homeless parents were more likely to report that their living situation negatively impacted their child's play, development, education, safety, and health.

Prenatal screening for trisomy 21: a comparative performance and cost analysis of different screening strategies.

BACKGROUND: Prenatal screening for chromosome aneuploidies have constantly been evolving, especially with the introduction of cell-free fetal DNA (cfDNA) screening in the most recent years. This study compares the performance, costs and timing of test results of three cfDNA screening implementation strategies: contingent, reflex and primary. METHODS: We modelled enhanced first trimester screening (eFTS) as the first-tier test in contingent or reflex strategies. cfDNA test was performed contingent on or reflex from eFTS results. A comparison was made between cfDNA screening using sequencing technology and Rolling Circle Amplification (RCA)/imaging solution. All model assumptions were based on results from previous publications or information from the Ontario prenatal screening population. RESULTS: At an eFTS risk cut-off of ≥1/1000, contingent and reflex cfDNA screening have the same detection rate (DR) (94%) for trisomy 21. Reflex cfDNA screening using RCA/Imaging solution provided the lowest false positive rate and cost. The number of women requiring genetic counselling and diagnostic testing was significantly reduced and women received their cfDNA screening result 9 days sooner compared with the contingent model. While primary cfDNA screening improved the trisomy 21 DR by 3-5%, it was more costly and more women required diagnostic testing. CONCLUSION: Reflex cfDNA screening is the most cost-effective prenatal screening strategy. It can improve the efficiency of prenatal aneuploidy screening by reducing the number of patient visits and providing more timely results.

Immunization of looked-after children and young people: a review of the literature.

BACKGROUND: Numbers of looked-after children and young people (LACYP) in the UK have risen over the last seven years. Looked-after children and young people should receive regular health assessments, including establishing immunization status and, if needed, developing a health plan to achieve full immunization. The Department for Education publish data on immunizations among LACYP to monitor both how well they are immunized and service performance. METHODS: A literature review was conducted using four databases (PubMed, Embase, Scopus and Web of Science) on immunization status of LACYP, factors affecting uptake and challenges to immunization, and interventions to improve immunization rates. RESULTS: Thirty-two papers were identified, 16 of which were UK based. Looked-after children and young people are less likely to be 'up-to-date' with their immunizations than children in the general population. Looked-after children and young people are less likely to receive timely immunizations, and older LACYP are less likely to be 'up-to-date' than younger LACYP. Barriers to immunization include failure to attend health checks, absence from school and frequent placement moves. Unknown and discrepant immunization histories, name changes, sharing of information between organizations and obtaining consent for immunizations are also challenges. CONCLUSIONS: In recent years, immunization of LACYP has been given a higher priority. However, the immunization figures produced by the Department for Education are problematic because of challenges in determining whether the child is 'up-to-date', and data are not comparable with the general population; ideally, this should be changed to correspond to routine immunization data. In the interim, for reporting purposes, the use of a tool to assist with determining a child's immunization status would be beneficial. When a child's immunization status is incomplete or unknown, Public Health England's algorithm for vaccination of individuals with uncertain or incomplete status should be used. Practice to improve immunization uptake amongst LACYP needs to be evaluated to develop evidence-based recommendations.

Disruption of the ASTN2/TRIM32 locus at 9q33.1 is a risk factor in males for autism spectrum disorders, ADHD and other neurodevelopmental phenotypes.

Rare copy number variants (CNVs) disrupting ASTN2 or both ASTN2 and TRIM32 have been reported at 9q33.1 by genome-wide studies in a few individuals with neurodevelopmental disorders (NDDs). The vertebrate-specific astrotactins, ASTN2 and its paralog ASTN1, have key roles in glial-guided neuronal migration during brain development. To determine the prevalence of astrotactin mutations and delineate their associated phenotypic spectrum, we screened ASTN2/TRIM32 and ASTN1 (1q25.2) for exonic CNVs in clinical microarray data from 89 985 individuals across 10 sites, including 64 114 NDD subjects. In this clinical dataset, we identified 46 deletions and 12 duplications affecting ASTN2. Deletions of ASTN1 were much rarer. Deletions near the 3' terminus of ASTN2, which would disrupt all transcript isoforms (a subset of these deletions also included TRIM32), were significantly enriched in the NDD subjects (P = 0.002) compared with 44 085 population-based controls. Frequent phenotypes observed in individuals with such deletions include autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), speech delay, anxiety and obsessive compulsive disorder (OCD). The 3'-terminal ASTN2 deletions were significantly enriched compared with controls in males with NDDs, but not in females. Upon quantifying ASTN2 human brain RNA, we observed shorter isoforms expressed from an alternative transcription start site of recent evolutionary origin near the 3' end. Spatiotemporal expression profiling in the human brain revealed consistently high ASTN1 expression while ASTN2 expression peaked in the early embryonic neocortex and postnatal cerebellar cortex. Our findings shed new light on the role of the astrotactins in psychopathology and their interplay in human neurodevelopment.

Utility of whole-exome sequencing for those near the end of the diagnostic odyssey: time to address gaps in care.

An accurate diagnosis is an integral component of patient care for children with rare genetic disease. Recent advances in sequencing, in particular whole-exome sequencing (WES), are identifying the genetic basis of disease for 25-40% of patients. The diagnostic rate is probably influenced by when in the diagnostic process WES is used. The Finding Of Rare Disease GEnes (FORGE) Canada project was a nation-wide effort to identify mutations for childhood-onset disorders using WES. Most children enrolled in the FORGE project were toward the end of the diagnostic odyssey. The two primary outcomes of FORGE were novel gene discovery and the identification of mutations in genes known to cause disease. In the latter instance, WES identified mutations in known disease genes for 105 of 362 families studied (29%), thereby informing the impact of WES in the setting of the diagnostic odyssey. Our analysis of this dataset showed that these known disease genes were not identified prior to WES enrollment for two key reasons: genetic heterogeneity associated with a clinical diagnosis and atypical presentation of known, clinically recognized diseases. What is becoming increasingly clear is that WES will be paradigm altering for patients and families with rare genetic diseases.

Social determinants of parent-child interaction in the UK.

BACKGROUND: Children are shaped in part by their environment and one rich in communication is therefore beneficial. Activities such as play and reading have long lasting positive effects on development. This study examined the social and demographic characteristics of mothers who play with, read to and tell stories to their child, using data from the UK-wide Millennium Cohort Study (MCS). METHODS: The study included 14 034 mothers of singleton 5-year-old children. Using data from the first and third sweeps of the MCS, we examined how often mothers engaged with their child in playing, reading and telling stories, according to their social and demographic characteristics: ethnicity, socio-economic status, highest academic qualification, lone mother status, age at birth of cohort child, number of children and employment status. Adjusted logistic regression analyses were conducted using Stata. RESULTS: When their children were 5 years old, 22% of mothers reported playing, 51% reading and 13% telling stories everyday. Indian, Pakistani, Bangladeshi and Black mothers were significantly less likely to play with their child at least weekly compared with White mothers. The same applied to lone mothers compared with those living with a partner. Mothers with academic qualifications lower than degree level were less likely to read at least once weekly. Compared with mothers who worked full-time, those who worked part-time, were 'on-leave' or unemployed, were more likely to play with, and read to, their child at least weekly. Mothers with more than one child were significantly less likely to engage at least weekly in any of the three activities studied. CONCLUSIONS: We found significant inequalities in the frequency of playing, reading and telling stories according to sociodemographic characteristics. This information is important to be able to target more effectively vulnerable children using established public health initiatives, like 'Bookstart' and 'Surestart', aimed at promoting play, reading and story telling.

Impact of pregnancy vaccine uptake and socio-demographic determinants on subsequent childhood Measles, Mumps and Rubella vaccine uptake: A UK birth cohort study.

BACKGROUND: We examined the association between socio-demographic determinants and uptake of childhood Measles, Mumps & Rubella (MMR) vaccines and the association between pregnant women's pertussis vaccine uptake and their children's MMR vaccine uptake. METHODS: We used nationally-representative linked mother-baby electronic records from the United Kingdom's Clinical-Practice-Research-Datalink. We created a birth cohort of children born between 01.01.2000 and 12.12.2020. We estimated the proportion vaccinated with first MMR vaccine by age 2 years and first and second MMR vaccines by age 5 years. We used survival-analysis and Cox proportional hazard models to examine the association between deprivation, ethnicity and maternal age and pertussis vaccination in pregnancy and children's MMR uptake. RESULTS: Overall, 89.4 % (710,797/795,497) of children had first MMR by age 2 years and 92.6 % (736,495/795,497) by age 5 years. Among children still in the cohort when second MMR was due, 85.9 % (478,480/557,050) had two MMRs by age 5 years. Children from the most-deprived areas, children of Black ethnicity and children of mothers aged < 20 years had increased risk of being unvaccinated compared with children from the least-deprived areas, White children and children of mothers aged 31-40 years: first MMR by 5 years, adjusted Hazard Ratios (HR):0.86 (CI:0.85-0.87), HR:0.87 (CI:0.85-0.88) & HR:0.89 (CI:0.88-0.90) respectively. Deprivation was the determinant associated with the greatest risk of missed second MMR: adjusted HR:0.82 (CI:0.81-0.83). Children of mothers vaccinated in pregnancy were more likely than children of unvaccinated mothers to have MMR vaccines after adjusting for ethnicity, deprivation, and maternal age (First and Second MMRs adjusted HRs:1.43 (CI:1.41-1.45), 1.49 (CI:1.45-1.53). CONCLUSION: Children from most-deprived areas are less likely to have MMR vaccines compared with children from least-deprived areas. Mothers who take up pregnancy vaccines are more likely to have their children vaccinated with MMR. Healthcare services should promote and facilitate access to both maternal and childhood vaccines during pregnancy.

Prenatal screening for preeclampsia: the roles of placental growth factor and pregnancy-associated plasma protein A in the first trimester and placental growth factor and soluble fms-like tyrosine kinase 1-placental growth factor ratio in the early second trimester.

BACKGROUND: Professional societies have recommended universal first trimester screening for preeclampsia and a second or third trimester soluble fms-like tyrosine kinase-1-placental growth factor ratio test to assess for preeclampsia and its severity. However, it may not be feasible to implement the most optimal screening protocol for preeclampsia in the first trimester which uses a combination of maternal characteristics, maternal biophysical and biochemical markers due to limitations in the access to uterine artery doppler ultrasound. There are inconsistent findings on how early in the second trimester the fms-like tyrosine kinase-1-placental growth factor ratio begins to provide useful information in preeclampsia prediction. OBJECTIVE: This study aimed to assess the accuracy of (1) a combination of maternal characteristics, maternal serum pregnancy-associated plasma protein A, and placental growth factor in the screening for preeclampsia in the first trimester; and (2) placental growth factor or soluble fms-like tyrosine kinase-1-placental growth factor ratio in the prediction of preeclampsia in the early second trimester. STUDY DESIGN: This retrospective case-control study used frozen residual blood samples from women who had aneuploidy screening and delivered at a tertiary center. The case group included pregnancies with gestational hypertension or preeclampsia (further classified as early-onset [birth at <34 weeks' gestation] and preterm preeclampsia [birth at <37 weeks' gestation]). Each case was matched with 3 control pregnancies by date of blood sample draw, gestational age at first blood sample draw, maternal age, maternal ethnicity, type of multiple-marker screening, and amount of residual sample. Mann-Whitney U tests were used to assess the associations between serum markers and the risk of preeclampsia. Logistic regressions were used to assess if the risk of preeclampsia can be predicted using a combination of maternal characteristics and serum markers. RESULTS: The case group included 146 preeclampsia and 295 gestational hypertension cases. Compared with the controls, preeclampsia cases had significantly lower first-trimester pregnancy-associated plasma protein A and placental growth factor. At a 20% false-positive rate, 71% of early-onset and 58% of preterm preeclampsia cases can be predicted using maternal characteristics, pregnancy-associated plasma protein A, and placental growth factor. Preeclampsia cases had lower second-trimester placental growth factor and a higher soluble fms-like tyrosine kinase-1-placental growth factor ratio. At a 10% false-positive rate, 80% and 53% of early-onset preeclampsia can be predicted using maternal characteristics and placental growth factor or soluble fms-like tyrosine kinase-1-placental growth factor ratio, respectively. CONCLUSION: The current first-trimester aneuploidy screening programs may be expanded to identify women at increased risk of developing preeclampsia. Early in the second trimester, placental growth factor alone provided better prediction for preeclampsia compared with the soluble fms-like tyrosine kinase-1-placental growth factor ratio.

'Now I understand': consulting parents on chart design and parental information for the UK-WHO child growth charts.

BACKGROUND: Regular assessment of growth is an important part of child health surveillance in the UK and most parents are very interested in their child's growth. UK parents are given a personal child health record (PCHR), including growth charts, which are plotted during baby clinic visits. Parents were consulted as part of the process of designing new UK charts to incorporate the World Health Organization growth standard. This paper describes the main themes that emerged and how they influenced the final design. METHOD: Three sets of consultations with 47 parents were conducted to collect preliminary information, and to evaluate proposed chart designs, instructions and written information for parents. RESULTS: At every consultation, the impact of the depiction of the 50th centile line in bold was mentioned spontaneously by parents. They also found aspects of the charts unclear, including the implications of a recorded weight on any particular centile, the difficulty of understanding existing text about charts in the PCHR, their preference for using pounds and ounces rather than metric weights and confusion about how frequently babies should be weighed. This led to the production of parental information including explanation of these issues which were then tested in two further sets of focus groups. CONCLUSION: Involving parents in the process of designing growth charts and information influenced the finished design and the text in the PCHR. Ensuring information meets parents' needs is important to ensure successful growth monitoring.

Prenatal diagnosis of Jeune-like syndromes with two-dimensional and three-dimensional sonography.

The purpose of this article is to describe the use of three-dimensional sonography as an adjuvant to two-dimensional sonography facilitating an earlier and more definitive diagnosis of Jeune and Jeune-like syndromes in the second trimester. We report two cases in which three-dimensional sonography facilitated the diagnosis of these malformations. A diagnosis of Jeune syndrome was made in our first case. Our second case was found to be short-rib polydactyly syndrome Type IV. Three-dimensional skeletal survey visualized short ribs, short limbs, the presence of normal scapulae, and the absence of polydactyly in both cases. Three-dimensional sonography can assist two-dimensional sonography in providing a more accurate display of skeletal anomalies, limb abnormalities, and facial features.

Measuring disadvantage in the early years in the UK: A systematic scoping review.

Background: The relationship between disadvantage and child health in the early years is well established. For this evidence base to most helpfully inform services, we need to better understand how disadvantage is conceptualised and measured in the literature. We aimed to conceptualise disadvantage measured in child health literature and explore the associations between disadvantage and child health using these measures. Method: We conducted a scoping review using systematic methods to identify key concepts of disadvantage used in empirical child health literature. We searched MEDLINE, Scopus, and grey literature for studies exploring the association between disadvantage and child health outcomes for children aged 0-5 in the United Kingdom. We extracted and analysed data from 86 studies. Results: We developed a framework describing two domains, each with two attributes conceptualising disadvantage: level of disadvantage indicator (individual and area) and content of disadvantage indicator (social and economic). Individual-level measures of disadvantage tended to identify stronger associations between disadvantage and child health compared with area-level measures. Conclusion: The choice of disadvantage indicators, particularly whether individual- or area-level, can affect the inferences made about the relationship between disadvantage and child health. Better access to individual-level disadvantage indicators in administrative data could support development and implementation of interventions aimed at reducing child health inequalities in the early years.

Murine trisomy 16 model of Down's syndrome: central nervous system electron microscopic observations.

Murine trisomy 16 is an excellent model for the human Down's syndrome (DS). Electron microscopic (EM) observations were made of the cortical plate within the developing telencephalic vesicle at the gestational age of E17. The EM observations revealed: (A) microtubular profiles which were more coiled and curved in the trisomic condition; (B) poor cell-to-cell apposition and increased cellular membrane fragmentation in trisomy 16; (C) increased nuclear contour irregularity in trisomic neurons; (D) significant decrease in the cross-sectional area of neuronal nuclei in trisomy 16 (p less than 0.01). The microtubular observations lend credence to the hypothesis that abnormal cytoskeletal interactions may underlie the mental deficiency seen in DS and may predispose to the eventual development of Alzheimer's disease (AD) in DS individuals. The cellular membrane findings may be related to reported CNS membrane lipid abnormalities in DS. The nuclear morphologic observations may be related to the reported differences in chromatin and nuclear histone expression in AD. These results strengthen the role of the trisomy 16 mouse as a model for DS and potentially for AD.

Bacterial meningitis in the newborn: a prospective study of mortality and morbidity.

Neonatal bacterial meningitis is a serious disease around the world, with the incidence changing little in the past 30 years. Group B streptococci, Escherichia coli, and Klebsiella pneumoniae are common causative organisms and lumbar puncture remains the definitive method of diagnosis. The mortality rate has declined in industrialized countries over the years, from almost 50% in the 1970s to less than 10% in 1997. However, neurological sequelae are still frequently observed despite major changes in treatment. Preliminary analysis of our own data from a prospective study of cases in the United Kingdom suggests that treatment with third generation cephalosporins is related to a decrease in mortality but not morbidity.

Use of an east end children's accident and emergency department for infants: a failure of primary health care?

OBJECTIVE: To ascertain why parents use an accident and emergency department for health care for their infants. DESIGN: Prospective one month study. SETTING: One accident and emergency department of a children's hospital in the east end of London. SUBJECTS: Parents of 159 infants aged < 9 months attending as self referrals (excluding infants attending previously or inpatients within one month, parents advised by the hospital to attend if concerned about their child's health, infants born abroad and arrived in Britain within the previous month). MAIN MEASURES: Details of birth, postnatal hospital stay, contact with health professionals, perceptions of roles of community midwife and health visitor, and current attendance obtained from a semistructured questionnaire administered in the department by a research health visitor; diagnosis, discharge, and follow up. RESULTS: 152(96%) parents were interviewed, 43(28%) of whom were single parent and 68(45%) first time mothers. Presenting symptoms included diarrhoea or vomiting, or both (34, 22%), crying (21, 14%), and feeding difficulties (10, 7%). Respiratory or gastrointestinal infection was diagnosed in 70(46%) infants. Only 17(11%) infants were admitted; hospital follow up was arranged for 27(20%) infants not admitted. Most (141, 94%) parents were registered with a general practitioner; 146(27%) had contact with the community midwife and 135(89%) the health visitor. CONCLUSION: Most attendances were for problems more appropriately dealt with by primary care professionals owing to patients' perceptions of hospital and primary health care services. IMPLICATIONS: Closer cooperation within the health service is needed to provide a service responsive to the real needs of patients.

Meningitis in infancy in England and Wales: follow up at age 5 years.

OBJECTIVE: To describe important sequelae occurring among a cohort of children aged 5 years who had had meningitis during the first year of life and who had been identified by a prospective national study of meningitis in infancy in England and Wales between 1985 and 1987. DESIGN: Follow up questionnaires asking about the children's health and development were sent to general practitioners and parents of the children and to parents of matched controls. The organism that caused the infection and age at infection were also recorded. SETTING: England and Wales. PARTICIPANTS: General practitioners and parents of children who had had meningitis before the age of 1 year and of matched controls. MAIN OUTCOME MEASURES: The prevalence of health and developmental problems and overall disability among children who had had meningitis compared with controls. RESULTS: Altogether, 1584 of 1717 (92.2%) children who had had meningitis and 1391 of 1485 (93.6%) controls were successfully followed up. Among children who survived to age 5 years 247 of 1584 (15.6%) had a disability; there was a 10-fold increase in the risk of severe or moderate disability at 5 years of age among children who had had meningitis (relative risk 10.3, 95% confidence interval 6.7 to 16.0, P<0.001). There was considerable variation in the rates of severe or moderate disability in children infected with different organisms. CONCLUSION: The long term consequences of having meningitis during the first year of life are significant: 32 of 1717 (1.8%) children died within five years. Not only did almost a fifth of children with meningitis have a permanent, severe or moderately severe disability, but subtle deficits were also more prevalent.

Prevention, treatment and outcomes of bacterial meningitis in childhood.

Meningitis is more likely to occur in childhood that at any other age. Preventive measures, in the form of vaccination programmes targeted at certain at-risk age groups, have drastically reduced the incidence in recent years. Early identification of symptoms remains vital in order to prevent mortality and reduce the likelihood of long-term effects.

Teenagers' understandings of and attitudes towards vaccines and vaccine-preventable diseases: a qualitative study.

BACKGROUND: To examine immunisation information needs of teenagers we explored understandings of vaccination and vaccine-preventable diseases, attitudes towards immunisation and experiences of immunisation. Diseases discussed included nine for which vaccines are currently offered in the UK (human papillomavirus, meningitis, tetanus, diphtheria, polio, whooping cough, measles, mumps and rubella), and two not currently included in the routine UK schedule (hepatitis B and chickenpox). METHODS: Twelve focus groups conducted between November 2010 and March 2011 with 59 teenagers (29 girls and 30 boys) living in various parts of Scotland. RESULTS: Teenagers exhibited limited knowledge and experience of the diseases, excluding chickenpox. Measles, mumps and rubella were perceived as severe forms of chickenpox-like illness, and rubella was not associated with foetal damage. Boys commonly believed that human papillomavirus only affects girls, and both genders exhibited confusion about its relationship with cancer. Participants considered two key factors when assessing the threat of diseases: their prevalence in the UK, and their potential to cause fatal or long-term harm. Meningitis was seen as a threat, but primarily to babies. Participants explained their limited knowledge as a result of mass immunisation making once-common diseases rare in the UK, and acknowledged immunisation's role in reducing disease prevalence. CONCLUSIONS: While it is welcome that fewer teenagers have experienced vaccine-preventable diseases, this presents public health advocates with the challenge of communicating benefits of immunisation when advantages are less visible. The findings are timely in view of the Joint Committee on Vaccination and Immunisation's recommendation that a booster of meningitis C vaccine should be offered to teenagers; that teenagers did not perceive meningitis C as a significant threat should be a key concern of promotional information. While teenagers' experiences of immunisation in school were not always positive, they seemed enthusiastic at the prospect of introducing more vaccines for their age group.