Adverse events following immunisation: Prospective cohort study evaluating Australian children presenting to specialist immunisation clinics

OBJECTIVE

Prior experience of an adverse event following immunisation is a known barrier to vaccination. Limited Australian data evaluating adverse event recurrence among children exists to inform clinical decisions. We aimed to assess adverse event following immunisation recurrence among children with prior adverse events and to evaluate if family history increased adverse event risk.

METHODS

A prospective cohort study was conducted from March 3rd until August 18th, 2023. Children ≤ 16 years with prior adverse events following immunisation in themselves or family were recruited from specialist immunisation clinics at two quaternary paediatric hospitals. Adverse event outcomes were collected via surveys administered at presentation, three, and eight days post vaccination, and analysed by key characteristics and potential risk factors.

RESULTS

Forty three of forty nine (43/49, 87.8 %) children enrolled received further vaccines. Of those who completed the follow up surveys, 50.0 % (16/32) reported an adverse event. Recurrence of prior adverse events occurred for 23.3 % (10/43, 95 % CI: 11.8 % - 38.6 %) of the cohort. Two of twelve (2/12, 16.7 %) participants with prior serious adverse events who received further vaccines reported a serious adverse event recurrence. No post review serious adverse events were observed in children with prior non serious adverse events. Neurological conditions were a risk factor for prior (neurological condition 3/3 versus no neurological condition 2/40, p < 0.001) and post review (neurological condition 2/3 versus no neurological condition 0/28, p = 0.006) post vaccination seizures. Family history had no relationship to post review adverse events (family history 5/8 versus no family history 11/23, p = 0.685).

CONCLUSION

Revaccination is safe for the majority of children with a personal or family history of adverse event following immunisation.

The development and evaluation of a vaccination pathway for children with intellectual and developmental disability and needle fear

This qualitative study describes the development and evaluation of a clinical pathway to facilitate the implementation of catch-up vaccinations for children with significant needle fear, particularly in children with developmental disabilities. The Specialist Immunization Team, based at a tertiary level teaching children's hospital, participated in process mapping activities using Motivational Interviewing (MI) techniques and reflective discussions. Team members developed a clinical pathway by incorporating parental feedback from semistructured interviews and clinical expertise from within the team, facilitated by colleagues from the Child Development Unit. A process map was developed that included process strengths and touch points with an action plan that was discussed and agreed upon. A repeat process mapping activity was conducted 16 months later. Reports from parental feedback included: positive, efficient, and successful experiences of having their child undergo catch-up vaccinations. The experience empowered families for further procedures. Team members reported improvements in triaging appropriate children for the pathway, and an increase in confidence to interact and manage behaviors of children with significant anxiety and challenging behaviors. They also reported an increase in successful vaccinations with improved clinical judgment of facilitating the sedation pathway. This study demonstrates that using group facilitation using motivational interviewing in reflective discussions and process mapping utilizing parent and staff feedback in service improvement activities results in efficient and successful service delivery with improved patient outcomes.

Seroprevalence of Japanese encephalitis virus-specific antibodies in Australia following novel epidemic spread: protocol for a national cross-sectional study

INTRODUCTION

Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus that causes encephalitis and other morbidity in Southeast Asia. Since February 2022, geographically dispersed JEV human, animal and vector detections occurred on the Australian mainland for the first time. This study will determine the prevalence of JEV-specific antibodies in human blood with a focus on populations at high risk of JEV exposure and determine risk factors associated with JEV seropositivity by location, age, occupation and other factors.

METHOD

Samples are collected using two approaches: from routine blood donors (4153 samples), and active collections targeting high-risk populations (convenience sampling). Consent-based sampling for the latter includes a participant questionnaire on demographic, vaccination and exposure data. Samples are tested for JEV-specific total antibody using a defined epitope-blocking ELISA, and total antibody to Australian endemic flaviviruses Murray Valley encephalitis and Kunjin viruses.

ANALYSIS

Two analytic approaches will occur: descriptive estimates of seroprevalence and multivariable logistic regression using Bayesian hierarchical models. Descriptive analyses will include unadjusted analysis of raw data with exclusions for JEV-endemic country of birth, travel to JEV-endemic countries, prior JEV-vaccination, and sex-standardised and age-standardised analyses. Multivariable logistic regression will determine which risk factors are associated with JEV seropositivity likely due to recent transmission within Australia and the relative contribution of each factor when accounting for effects within the model.

ETHICS

National Mutual Acceptance ethical approval was obtained from the Sydney Children's Hospitals Network Human Research Ethics Committee (HREC). Local approvals were sought in each jurisdiction. Ethical approval was also obtained from the Australian Red Cross Lifeblood HREC.

DISSEMINATION

Findings will be communicated to participants and their communities, and human and animal health stakeholders and policy-makers iteratively and after final analyses. Understanding human infection rates will inform procurement and targeted allocation of limited JEV vaccine, and public health strategies and communication campaigns, to at-risk populations.

Superior immunogenicity of mRNA over adenoviral vectored COVID-19 vaccines reflects B cell dynamics independent of anti-vector immunity: Implications for future pandemic vaccines

Both vector and mRNA vaccines were an important part of the response to the COVID-19 pandemic and may be required in future outbreaks and pandemics. The aim of this study was to validate whether immunogenicity differs for adenoviral vectored (AdV) versus mRNA vaccines against SARS-CoV-2, and to investigate how anti-vector immunity and B cell dynamics modulate immunogenicity. We enrolled SARS-CoV-2 infection-naïve health care workers who had received two doses of either AdV AZD1222 (n = 184) or mRNA BNT162b2 vaccine (n = 274) between April and October 2021. Blood was collected at least once, 10-48 days after vaccine dose 2 for antibody and B cell analyses. Median ages were 42 and 39 years, for AdV and mRNA vaccinees, respectively. Surrogate virus neutralization test (sVNT) and spike binding antibody titres were a median of 4.2 and 2.2 times lower, respectively, for AdV compared to mRNA vaccinees (p < 0.001). Median percentages of memory B cells that recognized fluorescent-tagged spike and RBD were 2.9 and 8.3 times lower, respectively for AdV compared to mRNA vaccinees. Titres of IgG reactive with human adenovirus type 5 hexon protein rose a median of 2.2-fold after AdV vaccination but were not correlated with anti-spike antibody titres. Together the results show that mRNA induced substantially more sVNT antibody than AdV vaccine, which reflected greater B cell expansion and targeting of the RBD rather than an attenuating effect of anti-vector antibodies. ClinicalTrials.gov Identifier: NCT05110911.

Successful Use of Cefiderocol to Treat a Multidrug-resistant Stenotrophomonas maltophilia Ventilator-associated Pneumonia in an Extremely Preterm Neonate

BACKGROUND

Ventilator-associated pneumonia (VAP) caries a morbidity and mortality risk in the preterm neonate, particularly in the context of rising global antimicrobial resistance driving infections due to multidrug-resistant Gram-negative bacteria. Cefiderocol, a siderophilic cephalosporin, has broad Gram-negative antimicrobial activity and central nervous system penetration and is used for the treatment of hospital-acquired pneumonia or VAP in adults. Scarce data exists on its use in neonates.

CASE

A female neonate born at 26 + 6 weeks developed VAP at 21 days of life. She was commenced on corticosteroids, vancomycin and ceftazidime but continued to deteriorate. Sputum cultures yielded Stenotrophomonas maltophilia resistant to trimethoprim/sulfamethoxazole, ciprofloxacin and ceftazidime, with potential susceptibility to cefiderocol. Cerebrospinal fluid showed an elevated white cell count. In view of worsening respiratory and hemodynamic status, antibiotic treatment was changed to cefiderocol monotherapy at 30 mg/kg/dose every 8 hours. Within 72 hours of commencing cefiderocol, the neonate was successfully extubated to variable-flow continuous positive airway pressure and showed ongoing clinical improvement.

CONCLUSIONS

Cefiderocol was integral for the care of our neonate without any immediate adverse safety consequences. We relied on dosing data from a conference abstract, due to the paucity of evidence on the use of novel antimicrobials. This lack of evidence is particularly concerning given preterm neonates are particularly vulnerable to infections with multidrug-resistant Gram-negative organisms due to their immature immune systems, prolonged hospital stay, repeated interventions and antimicrobial exposure.

Clinical and Epidemiologic Profile of Invasive Pneumococcal Disease in Australian Children Following the Relaxation of Nonpharmaceutical Interventions Against SARS-COV-2

A global resurgence of invasive pneumococcal disease (IPD) has been noted in children. We provide a detailed clinical and epidemiological analysis of IPD in Australian children following relaxation of nonpharmaceutical interventions against coronavirus disease 2019, revealing significant morbidity and mortality-even in vaccinated children without known predisposing risk factors. Almost half of the IPD cases were caused by serotypes not covered by the 13-valent pneumococcal conjugate vaccine.

A case report of disseminated Streptococcus pneumoniae infection complicated by infective endocarditis, septic arthritis and epidural abscess in an immunocompetent patient

Streptococcus pneumoniae is a highly virulent, vaccine-preventable pathogen which can cause disease on a spectrum from benign to fatal. Apart from pneumonia, it commonly causes septicaemia and meningitis. This case report describes an unusual range of complications in a 53-year-old Caucasian female presenting to a regional hospital, without any risk known factors for severe disease (such as extremes of age, immunodeficiency or co-morbidities). Progressing from an episode of otitis media, her condition rapidly progressed to mastoid sinusitis, septic arthritis, infective endocarditis, epidural abscesses and multiple subcutaneous abscesses. Following quick identification of S. pneumoniae from a positive blood culture, the patient was treated with high-dose benzylpenicillin and ceftriaxone and aggressive source control by surgery, enabling a good clinical recovery.

Comparative B cell and antibody responses induced by adenoviral vectored and mRNA vaccines against COVID-19

Both vector and mRNA vaccines were an important part of the response to the COVID-19 pandemic and may be required in future outbreaks and pandemics. However, adenoviral vectored (AdV) vaccines may be less immunogenic than mRNA vaccines against SARS-CoV-2. We assessed anti-spike and anti-vector immunity among infection-naïve Health Care Workers (HCW) following two doses of AdV (AZD1222) versus mRNA (BNT162b2) vaccine. 183 AdV and 274 mRNA vaccinees enrolled between April and October 2021. Median ages were 42 and 39 years, respectively. Blood was collected at least once, 10-48 days after vaccine dose 2. Surrogate virus neutralization test (sVNT) and spike binding antibody titres were a median of 4.2 and 2.2 times lower, respectively, for AdV compared to mRNA vaccinees (p<0.001). Median percentages of memory B cells that recognized fluorescent-tagged spike and RBD were 2.9 and 8.3 times lower, respectively for AdV compared to mRNA vaccinees. Titres of IgG reactive with human Adenovirus type 5 hexon protein rose a median of 2.2-fold after AdV vaccination but were not correlated with anti-spike antibody titres. Together the results show that mRNA induced substantially more sVNT antibody than AdV vaccine due to greater B cell expansion and targeting of the RBD. Pre-existing AdV vector cross-reactive antibodies were boosted following AdV vaccination but had no detectable effect on immunogenicity.

Tracking the clonal dynamics of SARS-CoV-2-specific T cells in children and adults with mild/asymptomatic COVID-19

Children infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) develop less severe coronavirus disease 2019 (COVID-19) than adults. The mechanisms for the age-specific differences and the implications for infection-induced immunity are beginning to be uncovered. We show by longitudinal multimodal analysis that SARS-CoV-2 leaves a small footprint in the circulating T cell compartment in children with mild/asymptomatic COVID-19 compared to adult household contacts with the same disease severity who had more evidence of systemic T cell interferon activation, cytotoxicity and exhaustion. Children harbored diverse polyclonal SARS-CoV-2-specific naïve T cells whereas adults harbored clonally expanded SARS-CoV-2-specific memory T cells. A novel population of naïve interferon-activated T cells is expanded in acute COVID-19 and is recruited into the memory compartment during convalescence in adults but not children. This was associated with the development of robust CD4⁺ memory T cell responses in adults but not children. These data suggest that rapid clearance of SARS-CoV-2 in children may compromise their cellular immunity and ability to resist reinfection.

COVID ‐19 in New South Wales children during 2021: severity and clinical spectrum

Objectives: To describe the severity and clinical spectrum of coronavirus disease 2019 (COVID‐19) in children during the 2021 New South Wales outbreak of the Delta variant of the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2).

Design, setting: Prospective cohort study in three metropolitan Sydney local health districts, 1 June – 31 October 2021.

Participants: Children under 16 years of age with positive SARS‐CoV‐2 nucleic acid test results admitted to hospital or managed by the Sydney Children’s Hospital Network (SCHN) virtual care team.

Main outcome measures: Age‐specific SARS‐CoV‐2 infection frequency, overall and separately for SCHN virtual and hospital patients; rates of medical and social reason admissions, intensive care admissions, and paediatric inflammatory multisystem syndrome temporally associated with SARS‐CoV‐2 per 100 SARS‐CoV‐2 infections; demographic and clinical factors that influenced likelihood of hospital admission.

Results: A total of 17 474 SARS‐CoV‐2 infections in children under 16 were recorded in NSW, of whom 11 985 (68.6%) received SCHN‐coordinated care, including 459 admitted to SCHN hospitals: 165 for medical reasons (1.38 [95% CI, 1.17–1.59] per 100 infections), including 15 admitted to intensive care, and 294 (under 18 years of age) for social reasons (2.45 [95% CI, 2.18–2.73] per 100 infections). In an analysis that included all children admitted to hospital and a random sample of those managed by the virtual team, having another medical condition (adjusted odds ratio [aOR], 7.42; 95% CI, 3.08–19.3) was associated with increased likelihood of medical admission; in univariate analyses, non‐asthmatic chronic respiratory disease was associated with greater (OR, 9.21; 95% CI, 1.61–174) and asthma/viral induced wheeze with lower likelihood of admission (OR, 0.38; 95% CI, 0.18–0.78). The likelihood of admission for medical reasons declined from infancy to 5–11 years, but rose again for those aged 12–15 years. Sex and Indigenous status did not influence the likelihood of admission.

Conclusion: Most SARS‐CoV‐2 infections (Delta variant) in children were asymptomatic or associated with mild disease. Hospitalisation was relatively infrequent, and most common for infants, adolescents, and children with other medical conditions. More children were hospitalised for social than for medical reasons.

The known: Information regarding disease severity and reasons for hospital admissions of children with COVID‐19 in Australia is very limited.

The new: In 2021, more NSW children with SARS‐CoV‐2 infections were hospitalised for social or welfare reasons (294, 64%; 2.45 per 100 infections) than for medical treatment (165, 36%; 1.38 per 100 infections). Children under six months of age, aged 12–15 years, or with another medical condition were more likely to be hospitalised than other children.

The implications: As acute COVID‐19 is typically mild in children, measures that protect them from SARS‐CoV‐2 but harm their overall wellbeing may be disproportionate. Community support for children with special care needs could reduce the number of hospitalisations.

COVID-19 in children. II: Pathogenesis, disease spectrum and management

The global disruption of the COVID-19 pandemic has impacted the life of every child either directly or indirectly. This review explores the pathophysiology, immune response, clinical presentation and treatment of COVID-19 in children, summarising the most up-to-date data including recent developments regarding variants of concern. The acute infection with SARS-CoV-2 is generally mild in children, whilst the post-infectious manifestations, including paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) and 'long COVID' in children, are more complex. Given that most research on COVID-19 has focused on adult cohorts and that clinical manifestations, treatment availability and impacts differ markedly in children, research that specifically examines COVID-19 in children needs to be prioritised.

COVID-19 in children: I. Epidemiology, prevention and indirect impacts

Children globally have been profoundly impacted by the coronavirus disease 2019 (COVID-19) pandemic. This review explores the direct and indirect public health impacts of COVID-19 on children. We discuss in detail the transmission dynamics, vaccination strategies and, importantly, the 'shadow pandemic', encompassing underappreciated indirect impacts of the pandemic on children. The indirect effects of COVID-19 will have a long-term impact beyond the immediate pandemic period. These include the mental health and wellbeing risks, disruption to family income and attendant stressors including increased family violence, delayed medical attention and the critical issue of prolonged loss of face-to-face learning in a normal school environment. Amplification of existing inequities and creation of new disadvantage are likely additional sequelae, with children from vulnerable families disproportionately affected. We emphasise the responsibility of paediatricians to advocate on behalf of this vulnerable group to ensure the longer-term effects of COVID-19 public health responses on the health and wellbeing of children are fully considered.

Lessons learnt during the COVID-19 pandemic: Why Australian schools should be prioritised to stay open

In 2020, school and early childhood educational centre (ECEC) closures affected over 1.5 billion school-aged children globally as part of the COVID-19 pandemic response. Attendance at school and access to ECEC is critical to a child's learning, well-being and health. School closures increase inequities by disproportionately affecting vulnerable children. Here, we summarise the role of children and adolescents in Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) transmission and that of schools and ECECs in community transmission and describe the Australian experience. In Australia, most SARS-CoV-2 cases in schools were solitary (77% in NSW and 67% in Victoria); of those that did progress to an outbreak, >90% involved fewer than 10 cases. Australian and global experience has demonstrated that SARS-CoV-2 is predominantly introduced into schools and ECECs during periods of heightened community transmission. Implementation of public health mitigation strategies, including effective testing, tracing and isolation of contacts, means schools and ECECs can be safe, not drivers of transmission. Schools and ECEC are essential services and so they should be prioritised to stay open for face-to-face learning. This is particularly critical as we continue to manage the next phase of the COVID-19 pandemic.

Vaccines for COVID-19: Where do we stand in 2021?

As of July 2021, over 3 billion doses of a COVID-19 vaccines have been administered globally, and there are now 19 COVID-19 vaccines approved for use in at least one country. Several of these have been shown to be highly effective both in clinical trials and real-world observational studies, some of which have included special populations of interest. A small number of countries have approved a COVID-19 vaccine for use in adolescents or children. These are laudable achievements, but the global vaccination effort has been challenged by inequitable distribution of vaccines predominantly to high income countries, with only 0.9% of people in low-income countries having received at least one dose of a COVID-19 vaccine. Addressing this inequity is of critical importance and will result in better control of SARS-CoV-2 globally. Other challenges include: the reduced protection from COVID-19 vaccines against some strains of SARS-CoV-2, necessitating the development of variant specific vaccines; and uncertainties around the duration of protection from vaccine-induced immunity.

Susceptibility to SARS-CoV-2 Infection Among Children and Adolescents Compared With Adults: A Systematic Review and Meta-analysis

IMPORTANCE

The degree to which children and adolescents are infected by and transmit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unclear. The role of children and adolescents in transmission of SARS-CoV-2 is dependent on susceptibility, symptoms, viral load, social contact patterns, and behavior.

OBJECTIVE

To systematically review the susceptibility to and transmission of SARS-CoV-2 among children and adolescents compared with adults.

DATA SOURCES

PubMed and medRxiv were searched from database inception to July 28, 2020, and a total of 13 926 studies were identified, with additional studies identified through hand searching of cited references and professional contacts.

STUDY SELECTION

Studies that provided data on the prevalence of SARS-CoV-2 in children and adolescents (younger than 20 years) compared with adults (20 years and older) derived from contact tracing or population screening were included. Single-household studies were excluded.

DATA EXTRACTION AND SYNTHESIS

PRISMA guidelines for abstracting data were followed, which was performed independently by 2 reviewers. Quality was assessed using a critical appraisal checklist for prevalence studies. Random-effects meta-analysis was undertaken.

MAIN OUTCOMES AND MEASURES

Secondary infection rate (contact-tracing studies) or prevalence or seroprevalence (population screening studies) among children and adolescents compared with adults.

RESULTS

A total of 32 studies comprising 41 640 children and adolescents and 268 945 adults met inclusion criteria, including 18 contact-tracing studies and 14 population screening studies. The pooled odds ratio of being an infected contact in children compared with adults was 0.56 (95% CI, 0.37-0.85), with substantial heterogeneity (I2 = 94.6%). Three school-based contact-tracing studies found minimal transmission from child or teacher index cases. Findings from population screening studies were heterogenous and were not suitable for meta-analysis. Most studies were consistent with lower seroprevalence in children compared with adults, although seroprevalence in adolescents appeared similar to adults.

CONCLUSIONS AND RELEVANCE

In this meta-analysis, there is preliminary evidence that children and adolescents have lower susceptibility to SARS-CoV-2, with an odds ratio of 0.56 for being an infected contact compared with adults. There is weak evidence that children and adolescents play a lesser role than adults in transmission of SARS-CoV-2 at a population level. This study provides no information on the infectivity of children.

Susceptibility to SARS-CoV-2 Infection Among Children and Adolescents Compared With Adults: A Systematic Review and Meta-analysis

Importance

The degree to which children and adolescents are infected by and transmit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unclear. The role of children and adolescents in transmission of SARS-CoV-2 is dependent on susceptibility, symptoms, viral load, social contact patterns, and behavior.

Objective

To systematically review the susceptibility to and transmission of SARS-CoV-2 among children and adolescents compared with adults.

Data Sources

PubMed and medRxiv were searched from database inception to July 28, 2020, and a total of 13 926 studies were identified, with additional studies identified through hand searching of cited references and professional contacts.

Study Selection

Studies that provided data on the prevalence of SARS-CoV-2 in children and adolescents (younger than 20 years) compared with adults (20 years and older) derived from contact tracing or population screening were included. Single-household studies were excluded.

Data Extraction and Synthesis

PRISMA guidelines for abstracting data were followed, which was performed independently by 2 reviewers. Quality was assessed using a critical appraisal checklist for prevalence studies. Random-effects meta-analysis was undertaken.

Main Outcomes and Measures

Secondary infection rate (contact-tracing studies) or prevalence or seroprevalence (population screening studies) among children and adolescents compared with adults.

Results

A total of 32 studies comprising 41 640 children and adolescents and 268 945 adults met inclusion criteria, including 18 contact-tracing studies and 14 population screening studies. The pooled odds ratio of being an infected contact in children compared with adults was 0.56 (95% CI, 0.37-0.85), with substantial heterogeneity (I2 = 94.6%). Three school-based contact-tracing studies found minimal transmission from child or teacher index cases. Findings from population screening studies were heterogenous and were not suitable for meta-analysis. Most studies were consistent with lower seroprevalence in children compared with adults, although seroprevalence in adolescents appeared similar to adults.

Conclusions and Relevance

In this meta-analysis, there is preliminary evidence that children and adolescents have lower susceptibility to SARS-CoV-2, with an odds ratio of 0.56 for being an infected contact compared with adults. There is weak evidence that children and adolescents play a lesser role than adults in transmission of SARS-CoV-2 at a population level. This study provides no information on the infectivity of children.

Transmission of SARS-CoV-2 in Australian educational settings: a prospective cohort study

BACKGROUND

School closures have occurred globally during the COVID-19 pandemic. However, empiric data on transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among children and in educational settings are scarce. In Australia, most schools have remained open during the first epidemic wave, albeit with reduced student physical attendance at the epidemic peak. We examined SARS-CoV-2 transmission among children and staff in schools and early childhood education and care (ECEC) settings in the Australian state of New South Wales (NSW).

METHODS

Laboratory-confirmed paediatric (aged ≤18 years) and adult COVID-19 cases who attended a school or ECEC setting while considered infectious (defined as 24 h before symptom onset based on national guidelines during the study period) in NSW from Jan 25 to April 10, 2020, were investigated for onward transmission. All identified school and ECEC settings close contacts were required to home quarantine for 14 days, and were monitored and offered SARS-CoV-2 nucleic acid testing if symptomatic. Enhanced investigations in selected educational settings included nucleic acid testing and SARS-CoV-2 antibody testing in symptomatic and asymptomatic contacts. Secondary attack rates were calculated and compared with state-wide COVID-19 rates.

FINDINGS

15 schools and ten ECEC settings had children (n=12) or adults (n=15) attend while infectious, with 1448 contacts monitored. Of these, 633 (43·7%) of 1448 had nucleic acid testing, or antibody testing, or both, with 18 secondary cases identified (attack rate 1·2%). Five secondary cases (three children; two adults) were identified (attack rate 0·5%; 5/914) in three schools. No secondary transmission occurred in nine of ten ECEC settings among 497 contacts. However, one outbreak in an ECEC setting involved transmission to six adults and seven children (attack rate 35·1%; 13/37). Across all settings, five (28·0%) of 18 secondary infections were asymptomatic (three infants [all aged 1 year], one adolescent [age 15 years], and one adult).

INTERPRETATION

SARS-CoV-2 transmission rates were low in NSW educational settings during the first COVID-19 epidemic wave, consistent with mild infrequent disease in the 1·8 million child population. With effective case-contact testing and epidemic management strategies and associated small numbers of attendances while infected, children and teachers did not contribute significantly to COVID-19 transmission via attendance in educational settings. These findings could be used to inform modelling and public health policy regarding school closures during the COVID-19 pandemic.

FUNDING

NSW Government Department of Health.

Progress and Pitfalls in the Quest for Effective SARS-CoV-2 (COVID-19) Vaccines

There are currently around 200 SARS-CoV-2 candidate vaccines in preclinical and clinical trials throughout the world. The various candidates employ a range of vaccine strategies including some novel approaches. Currently, the goal is to prove that they are safe and immunogenic in humans (phase 1/2 studies) with several now advancing into phase 2 and 3 trials to demonstrate efficacy and gather comprehensive data on safety. It is highly likely that many vaccines will be shown to stimulate antibody and T cell responses in healthy individuals and have an acceptable safety profile, but the key will be to confirm that they protect against COVID-19. There is much hope that SARS-CoV-2 vaccines will be rolled out to the entire world to contain the pandemic and avert its most damaging impacts. However, in all likelihood this will initially require a targeted approach toward key vulnerable groups. Collaborative efforts are underway to ensure manufacturing can occur at the unprecedented scale and speed required to immunize billions of people. Ensuring deployment also occurs equitably across the globe will be critical. Careful evaluation and ongoing surveillance for safety will be required to address theoretical concerns regarding immune enhancement seen in previous contexts. Herein, we review the current knowledge about the immune response to this novel virus as it pertains to the design of effective and safe SARS-CoV-2 vaccines and the range of novel and established approaches to vaccine development being taken. We provide details of some of the frontrunner vaccines and discuss potential issues including adverse effects, scale-up and delivery.

Vaccines for COVID-19: The current state of play

There is a strong consensus globally that a COVID-19 vaccine is likely the most effective approach to sustainably controlling the COVID-19 pandemic. An unprecedented research effort and global coordination has resulted in a rapid development of vaccine candidates and initiation of trials. Here, we review vaccine types, and progress with 10 vaccine candidates against SARS-CoV-2 - the virus that causes COVID-19 - currently undergoing early phase human trials. We also consider the many challenges of developing and deploying a new vaccine on a global scale, and recommend caution with respect to our expectations of the timeline that may be ahead.

0884 The Effect of Bariatric Surgery on Sleep Disordered Breathing in Adolescents and Young Adults

Introduction

Childhood obesity is the major risk factor sleep disordered breathing (SDB). Severely obese young people may require bariatric surgery for correction of obesity, if other methods of weight loss have failed. We aim to assess the effect of bariatric surgery on SDB, in adolescents and young adults.

Methods

We conducted a retrospective chart review study of patients who underwent bariatric surgery between January 1, 2006 and August 31, 2019 at Cincinnati Children’s Hospital. Only patients who had pre-operative and post-operative polysomnograms were included in the study.

Results

Twenty-seven children and young adults (female: 59.2%) met the criteria for entry into analysis. The mean age of subjects at the time of weight loss surgery was 17.9 years (range: 12.9 to 32.5). Majority of the patients underwent laparoscopic partial gastrectomy (85.2%) and the remaining underwent laparoscopic gastric bypass surgery (14.8%). The average duration of follow up for post study measurements after the surgery was 10.4 months (Range: 0.4 to 57.5). The median Body Mass Index (BMI) was significantly lower at post-surgery (49.9 kg/m2[IQR: 45.4-55.9][pre] vs 39.3 kg/m2[IQR: 33.9-46][post], P&lt;0.001). The median obstructive AHI was significantly reduced at post-surgery (6.7/hr[IQR: 3.1-16.4][pre] vs 2.6/hr[IQR: 1.6-6][post], P= 0.03). Median heart rate (HR) during REM (79 bpm[IQR:67-90][pre] vs 67 bpm[IQR: 59.7-72][post], P&lt;0.0001) and NREM (81 bpm[IQR:65-91][pre] vs 65 bpm[IQR: 58-73][post], P&lt;0.0001) sleep were significantly lower at post-surgery. There was no statistically significant difference in sleep architecture (sleep latency, arousal index and percentage of REM, N1 and N3 sleep, P&gt; 0.05) except N2 sleep (53.1% [IQR:47.7-57.3] [pre] vs 55.7% [IQR:51.4-63.7] [post], P= 0.03) which was significantly increased at post-surgery.

Conclusion

There was significant improvement in BMI and SDB after weight loss surgery in children and young adults. Interestingly, there was a decrease in heart rate during both REM and NREM sleep after surgery which may suggest a decrease in sympathetic activation due to improvement if SDB. The sleep architecture remained unchanged after surgery, except the percentage of N2 sleep.

Support

Cincinnati Children’s Hospital Research Foundation

International Nosocomial Infection Control Consortium (INICC) report, data summary of 45 countries for 2012-2017: Device-associated module

BACKGROUND

We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2012 to December 2017 in 523 intensive care units (ICUs) in 45 countries from Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific.

METHODS

During the 6-year study period, prospective data from 532,483 ICU patients hospitalized in 242 hospitals, for an aggregate of 2,197,304 patient days, were collected through the INICC Surveillance Online System (ISOS). The Centers for Disease Control and Prevention-National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI) were applied.

RESULTS

Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the medical-surgical ICUs, the pooled central line-associated bloodstream infection rate was higher (5.05 vs 0.8 per 1,000 central line-days); the ventilator-associated pneumonia rate was also higher (14.1 vs 0.9 per 1,000 ventilator-days,), as well as the rate of catheter-associated urinary tract infection (5.1 vs 1.7 per 1,000 catheter-days). From blood cultures samples, frequencies of resistance, such as of Pseudomonas aeruginosa to piperacillin-tazobactam (33.0% vs 18.3%), were also higher.

CONCLUSIONS

Despite a significant trend toward the reduction in INICC ICUs, DA-HAI rates are still much higher compared with CDC-NHSN's ICUs representing the developed world. It is INICC's main goal to provide basic and cost-effective resources, through the INICC Surveillance Online System to tackle the burden of DA-HAIs effectively.

Oral health care: The experience of Australian paediatricians

AIM

Many Australian children have dental decay in their deciduous teeth. Poor oral health can negatively impact a child's ability to eat, speak, sleep and socialise, with adverse impacts later in life. Paediatricians are well placed to examine children's teeth and to provide advice and education about oral health. Using a sample of Australian paediatricians, we aimed to determine: (i) self-reported oral health knowledge and skills, (ii) frequency of office-based oral health-related discussions, (iii) perceived role of paediatricians and (iv) barriers to oral health-related discussions.

METHODS

Members of a national network of paediatricians - the Australian Paediatric Research Network - completed a multi-topic survey, which included questions designed to assess oral health knowledge, current practice and barriers to oral health-related discussions.

RESULTS

Of 430 active members, 178 (41%) completed the survey. Few paediatricians reported very good/excellent ability to assess plaque build-up (8%) and dental caries (17%). Only 10% reported broaching the issue of oral health with all patients. Significant barriers included lack of professional training (52%) and other more pressing issues needing to be addressed (67%).

CONCLUSIONS

The increasing (and inequitable) rates of dental decay in Australian children mean that paediatricians should play a key role in the management of children's oral health. Many paediatricians reported a lack of specific training in oral health and limited ability to assess children and educate families. Despite the traditional divide between medicine and oral health, this study highlights the opportunity for Australian paediatricians to improve oral health through early intervention in the consultation room and beyond.

CSF neopterin, a useful biomarker in children presenting with influenza associated encephalopathy?

PURPOSE

Neurological complications of influenza cause significant disease in children. Central nervous system inflammation, the presumed mechanism of influenza-associated encephalopathy, is difficult to detect. Characteristics of children presenting with severe neurological complications of influenza, and potential biomarkers of influenza-associated encephalopathy are described.

METHODS

A multi-center, retrospective case-series of children with influenza and neurological complications during 2017 was performed. Enrolled cases met criteria for influenza-associated encephalopathy or had status epilepticus. Functional outcome at discharge was compared between groups using the Modified Rankin Scale (mRS).

RESULTS

There were 22 children with influenza studied of whom 11/22 had encephalopathy and 11/22 had status epilepticus. Only one child had a documented influenza immunization. The biomarker CSF neopterin was tested in 10/11 children with encephalopathy and was elevated in 8/10. MRI was performed in all children with encephalopathy and was abnormal in 8 (73%). Treatment of children with encephalopathy was with corticosteroids or intravenous immunoglobulin in 9/11 (82%). In all cases oseltamivir use was low (59%) while admission to the intensive care unit was frequent (14/22, 66%). Clinical outcome at discharge was moderate to severe disability (mRS score > 2) in the majority of children with encephalopathy (7/11, 64%), including one child who died. Children with status epilepticus recovered to near-baseline function in all cases.

CONCLUSION

Raised CSF neopterin was present in most cases of encephalopathy, and along with diffusion restriction on MRI, is a useful diagnostic biomarker. Lack of seasonal influenza vaccination represents a missed opportunity to prevent illness in children, including severe neurological disease.

Cytomorphological study of palpable breast lumps

Background: Breast lump is a very common clinical presentation for which fine needle aspiration cytology is often sought for. Because of it’s significant diagnositic value, FNAC has become a routine tool in the evaluation of the nature of the lesion. The objective of this study was to determine the cytomorphological patterns of breast lump in eastern part of Nepal among individuals attending Nobel Medical College. Materials and Methods: This was a retrospective descriptive study done in department of pathology from December 2012 to June 2015. All individuals presenting with breast lumps was included in this study. FNAC was done as per standard procedure and categorized as per United Kingdom National Health Survey Breast Screening Programme (UK-NHS-BSP) categories and further also categorized in to neoplastic and non-neolastic categories. Results: We studied 771 cases of breast lumps. Occurrence of breast lump was more common in female (97.4%). Neoplastic lesions accounted for 84.1% of cases out of which benign comprised of 94.6% and malignant comprised of 5.6%. Common benign lesions observed were that of fibroadenona (264) and fibrocystic changes (204). Ductal carcinoma was the most common malignant lesions. All malignant lesions were observed in older age and female sex population.Conclusion: Most of the cases of breast lumps are benign in nature and very few accounted for malignant cases. There is predominance of benign lesions in young age and increased malignancy in older age and female population. 

Primary small cell carcinoma of urinary bladder

Primary pure small cell carcinoma of the urinary bladder is an extremely rare and highly aggressive tumor with an average five-year survival rate of less than 10% as cited by multiple case reports. It accounts for about 0.5-1% of all bladder tumors. We present the case of an 87-years-old man; smoker hospitalized in the Department of Urology, from the Institute of Medicine, Kathmandu for intermittent painless hematuria. Ultrasonography showed a sessile tumoral growth. Transurethral resection of the tumor mass was performed and tissue fragments were sent to the pathologic lab to establish the histologic type, the degree of differentiation and invasion. Fragments of the tumor were fixed in 10% formaldehyde, paraffin embedded and processed as standard technique; the sections were stained with H and E and immunohistochemically with NSE and Cytokeratin.  A diagnosis of small cell carcinoma was established. Because of aggressive behavior and distinct treatment, the pathologist should watch out for the presence of small cell carcinoma component.

The demographics of molar pregnancies in BPKIHS

This is an analysis of the incidence of molar pregnancies and those of complete and partial molar pregnancies across the reproductive age range for BP Koirala Institute of Health Sciences (BPKIHS) in the period 2010-2011. Patients with molar pregnancies registered with BPKIHS from January 2008 to January 2010 were identified. The overall number of molar pregnancies registered was compared to the number of maternities (live births and still births) and total viable conceptions for this year. A retrospective study of 64 cases of molar pregnancies recorded at BPKIHS during the two year time was done. Medical records were reviewed. Incidence, clinical presentation and methods of diagnosis were studied. During the study period, there were 37 complete moles, 23 partial moles, 1 persistent gestational trophoblastic tumor, 1 choriocarcinoma, and 2 invasive moles. The incidence of molar pregnancy was 3.94 per 1000 deliveries. Median distribution was at 22 years of age, and majority (67%) presented during early second trimester. Twenty one (32.8%) women were of blood group A positive and ten (15.6%) presented with severe form of anemia. This study provides detailed data regarding the incidence of partial and complete molar pregnancies with increasing maternal age. It confirms the relation of molar pregnancy with age, and blood group. Complete mole had the highest incidence, affecting mostly younger age group, and usually in the first half of their pregnancy.

Effective control of hypertension in adults with chronic kidney disease

INTRODUCTION: Adequate control of hypertension in Chronic Kidney Disease patients is difficult to achieve. This study was designed to analyze the adequacy of Hypertension control in adults with CKD using different classes of antihypertensive drugs. METHODS: A cross-sectional observational study was done that included 85 patients with CKD admitted to our Medicine Department over a period of two years (2006-2008 A.D.). Presence of CKD was defined as glomerular filtration rate <60 ml/min per 1.73 m2 for more than three months or presence of albuminuria (albumin:creatinine ratio >30ug/mg). Adequate blood pressure control was defined as systolic blood pressure less than or equals to 130 and diastolic blood pressure less than or equals to 80 mm Hg. Data and Statistical analysis was done using SPSS Version 12 for Windows. RESULTS: Of all the CKD patients, 51.4% required three Anti-Hypertensive drugs combination for the effective control of Hypertension, while only 21% of CKD patients with hypertension was controlled on two drugs. CONCLUSION: Adequate control of blood pressure in CKD patient was shown to be most effective on combination of three antihypertensive drugs. A poor control was seen on patients taking less than three antihypertensive drugs. Keywords: antihypertensive drug; chronic kidney disease; glomerular filtration rate; hypertension.

Effective control of hypertension in adults with chronic kidney disease

INTRODUCTION

Adequate control of hypertension in Chronic Kidney Disease patients is difficult to achieve. This study was designed to analyze the adequacy of Hypertension control in adults with CKD using different classes of antihypertensive drugs.

METHODS

A cross-sectional observational study was done that included 85 patients with CKD admitted to our Medicine Department over a period of two years (2006-2008 A.D.). Presence of CKD was defined as glomerular filtration rate <60 ml/min per 1.73 m2 for more than three months or presence of albuminuria (albumin:creatinine ratio >30ug/mg). Adequate blood pressure control was defined as systolic blood pressure less than or equals to 130 and diastolic blood pressure less than or equals to 80 mm Hg. Data and Statistical analysis was done using SPSS Version 12 for Windows.

RESULTS

Of all the CKD patients, 51.4% required three Anti-Hypertensive drugs combination for the effective control of Hypertension, while only 21% of CKD patients with hypertension was controlled on two drugs.

CONCLUSION

Adequate control of blood pressure in CKD patient was shown to be most effective on combination of three antihypertensive drugs. A poor control was seen on patients taking less than three antihypertensive drugs.