The point prevalence of respiratory syncytial virus in hospital and community-based studies in children from Northern Australia:studies in a 'high-risk' population

Introduction: Respiratory syncytial virus (RSV) is the leading viral cause of acute lower respiratory infections globally, accounting for high morbidity and mortality burden among children aged less than 5 years. As candidate RSV vaccine trials in pregnant women and infants are underway a greater understanding of RSV epidemiology is now needed, especially in paediatric populations with high rates of acute and chronic respiratory disease. The objective was to identify RSV prevalence in children living in northern Australia, a region with a high respiratory disease burden. Methods: Data were sourced from 11 prospective studies (four hospital and seven community-based) of infants and children with acute and chronic respiratory illnesses, as well as otitis media, conducted between 1996 and 2017 inclusive. The data from northern Australian children in these trials were extracted and, where available and consented, their nasopharyngeal swabs (biobanked at -80°C) were tested by polymerase chain reaction assays for RSV-A and B, 16 other viruses and atypical respiratory bacterial pathogens. Results: Overall, 1127 children were included. Their median age was 1.8 years (interquartile range 0.5-4.9); 58% were male and 90% Indigenous, with 81% from remote communities. After human rhinoviruses (HRV), RSV was the second most prevalent virus (15%, 95% confidence interval (CI) 13-18). RSV prevalence was greatest amongst children aged less than 2 years hospitalised with bronchiolitis (47%, 95%CI 41.4-52.4), with more than two-thirds with RSV aged less than 6 months. In contrast, the prevalence of RSV was only 1-3.5% in other age groups and settings. In onethird of RSV cases, another respiratory virus was also detected. Individual viruses other than RSV and HRV were uncommon (0-9%). Conclusion: Combined data from 11 hospital and communitybased studies of children aged less than 18 years who lived in communities with a high burden of acute and chronic respiratory illness showed that RSV was second only to HRV as the most prevalent virus detected across all settings. RSV was the most frequently detected virus in infants hospitalised with bronchiolitis, including those aged less than 6 months. In contrast, RSV was uncommonly detected in children in community settings. In northern Australia, effective maternal and infant RSV vaccines could substantially reduce RSV bronchiolitis-related hospitalisations, including admissions of Indigenous infants from remote communities.</p

Mobile phones support adherence and retention of indigenous participants in a randomised controlled trial: strategies and lessons learnt

BackgroundEnsuring adherence to treatment and retention is important in clinical trials, particularly in remote areas and minority groups. We describe a novel approach to improve adherence, retention and clinical review rates of Indigenous children.MethodsThis descriptive study was nested within a placebo-controlled, randomised trial (RCT) on weekly azithromycin (or placebo) for 3-weeks. Indigenous children aged &le;24-months hospitalised with acute bronchiolitis were recruited from two tertiary hospitals in northern Australia (Darwin and Townsville). Using mobile phones embedded within a culturally-sensitive approach and framework, we report our strategies used and results obtained. Our main outcome measure was rates of adherence to medications, retention in the RCT and self-presentation (with child) to clinic for a clinical review on day-21.ResultsOf 301 eligible children, 76 (21%) families declined participation and 39 (13%) did not have access to a mobile phone. 186 Indigenous children were randomised and received dose one under supervision in hospital. Subsequently, 182 (99%) children received dose two (day-7), 169 (93%) dose three (day-14) and 180 (97%) attended their clinical review (day-21). A median of 2 calls (IQR 1&ndash;3) were needed to verify adherence. Importantly, over 97% of children remained in the RCT until their clinical endpoint at day-21.ConclusionsIn our setting, the use of mobile phones within an Indigenous-appropriate framework has been an effective strategy to support a clinical trial involving Australian Indigenous children in urban and remote Australia. Further research is required to explore other applications of this approach, including the impact on clinical outcomes

Three-weekly doses of azithromycin for Indigenous infants hospitalized with bronchiolitis: a multicentre, randomized, placebo-controlled trial

Background: Bronchiolitis is a major health burden in infants globally, particularly among Indigenous populations. It is unknown if 3 weeks of azithromycin improve clinical outcomes beyond the hospitalization period. In an international, double-blind randomized controlled trial, we determined if 3 weeks of azithromycin improved clinical outcomes in Indigenous infants hospitalized with bronchiolitis.Methods: Infants aged &le;24 months were enrolled from three centers and randomized to receive three once-weekly doses of either azithromycin (30 mg/kg) or placebo. Nasopharyngeal swabs were collected at baseline and 48 h later. Primary endpoints were hospital length of stay (LOS) and duration of oxygen supplementation monitored every 12 h until judged ready for discharge. Secondary outcomes were: day-21 symptom/signs, respiratory rehospitalizations within 6 months post-discharge and impact upon nasopharyngeal bacteria and virus shedding at 48 h.Results: Two hundred nineteen infants were randomized (n = 106 azithromycin, n = 113 placebo). No significant between-group differences were found for LOS (median 54 h for each group, difference = 0 h, 95% CI: &minus;6, 8; p = 0.8), time receiving oxygen (azithromycin = 40 h, placebo = 35 h, group difference = 5 h, 95% CI: &minus;8, 11; p = 0.7), day-21 symptom/signs, or rehospitalization within 6 months (azithromycin n = 31, placebo n = 25 infants, p = 0.2). Azithromycin reduced nasopharyngeal bacterial carriage (between-group difference 0.4 bacteria/child, 95% CI: 0.2, 0.6; p &lt; 0.001), but had no significant effect upon virus detection rates.Conclusion: Despite reducing nasopharyngeal bacterial carriage, three large once-weekly doses of azithromycin did not confer any benefit over placebo during the bronchiolitis illness or 6 months post hospitalization. Azithromycin should not be used routinely to treat infants hospitalized with bronchiolitis.Clinical trial registration: The trial was registered with the Australian and New Zealand Clinical Trials Register: Clinical trials number: ACTRN1261000036099

Transition of pediatric patients with bronchiectasis to adult medical care in the Northern Territory: A retrospective chart audit

BackgroundBronchiectasis is increasingly being recognized to exist in all settings with a high burden of disease seen in First Nations populations. With increasing numbers of pediatric patients with chronic illnesses surviving into adulthood, there is more awareness on examining the transition from pediatric to adult medical care services. We undertook a retrospective medical chart audit to describe what processes, timeframes, and supports were in place for the transition of young people (≥14 years) with bronchiectasis from pediatric to adult services in the Northern Territory (NT), Australia.MethodsParticipants were identified from a larger prospective study of children investigated for bronchiectasis at the Royal Darwin Hospital, NT, from 2007 to 2022. Young people were included if they were aged ≥14 years on October 1, 2022, with a radiological diagnosis of bronchiectasis on high-resolution computed tomography scan. Electronic and paper-based hospital medical records and electronic records from NT government health clinics and, where possible, general practitioner and other medical service attendance were reviewed. We recorded any written evidence of transition planning and hospital engagement from age ≥14 to 20 years.ResultsOne hundred and two participants were included, 53% were males, and most were First Nations people (95%) and lived in a remote location (90.2%). Nine (8.8%) participants had some form of documented evidence of transition planning or discharge from pediatric services. Twenty-six participants had turned 18 years, yet there was no evidence in the medical records of any young person attending an adult respiratory clinic at the Royal Darwin Hospital or being seen by the adult outreach respiratory clinic.ConclusionThis study demonstrates an important gap in the documentation of delivery of care, and the need to develop an evidence-based transition framework for the transition of young people with bronchiectasis from pediatric to adult medical care services in the NT

Emerging pneumococcal carriage serotypes in a high-risk population receiving universal 7-valent pneumococcal conjugate vaccine and 23-valent polysaccharide vaccine since 2001

<p>Abstract</p> <p>Background</p> <p>In Australia in June 2001, a unique pneumococcal vaccine schedule commenced for Indigenous infants; seven-valent pneumococcal conjugate vaccine (7PCV) given at 2, 4, and 6 months of age and 23-valent pneumococcal polysaccharide vaccine (23PPV) at 18 months of age. This study presents carriage serotypes following this schedule.</p> <p>Methods</p> <p>We conducted cross sectional surveys of pneumococcal carriage in Aboriginal children 0 to 6 years of age living in remote Aboriginal communities (RACs) in 2003 and 2005. Nasal secretions were collected and processed according to published methods.</p> <p>Results</p> <p>902 children (mean age 25 months) living in 29 communities in 2003 and 818 children (mean age 35 months) in 17 communities in 2005 were enrolled. 87% children in 2003 and 96% in 2005 had received two or more doses of 7PCV. From 2003 to 2005, pneumococcal carriage was reduced from 82% to 76% and reductions were apparent in all age groups; 7PCV-type carriage was reduced from 11% to 8%, and 23PPV-non-7PCV-type carriage from 31% to 25% respectively. Thus non-23PPV-type carriage increased from 57% to 67%. All these changes were statistically significant, as were changes for some specific serotypes. Shifts could not be attributed to vaccination alone. The top 10 of 40 serotypes identified were (in descending order) 16F, 19A, 11A, 6C, 23B, 19F, 6A, 35B, 6B, 10A and 35B. Carriage of penicillin non-susceptible (MIC > = 0.12 μg/mL) strains (15% overall) was detected in serotypes (descending order) 19A, 19F, 6B, 16F, 11A, 9V, 23B, and in 4 additional serotypes. Carriage of azithromycin resistant (MIC > = 2 μg/mL) strains (5% overall), was detected in serotypes (descending order) 23B, 17F, 9N, 6B, 6A, 11A, 23F, and in 10 additional serotypes including 6C.</p> <p>Conclusion</p> <p>Pneumococcal carriage remains high (~80%) in this vaccinated population. Uptake of both pneumococcal vaccines increased, and carriage was reduced between 2003 and 2005. Predominant serotypes in combined years were 16F, 19A, 11A, 6C and 23B. Antimicrobial non-susceptibility was detected in these and 17 additional serotypes. Shifts in serotype-specific carriage suggest a need more research to clarify the association between pneumococcal vaccination and carriage at the serotype level.</p