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"Morris, Peter S."
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Epidemiology of nasopharyngeal carriage of respiratory bacterial pathogens in children and adults: cross-sectional surveys in a population with high rates of pneumococcal disease
by
Morris, Peter S
,
Leach, Amanda J
,
Fisher, Janelle
in
Adolescent
,
Adult
,
Australia - epidemiology
2010
Background
To determine the prevalence of carriage of respiratory bacterial pathogens, and the risk factors for and serotype distribution of pneumococcal carriage in an Australian Aboriginal population.
Methods
Surveys of nasopharyngeal carriage of
Streptococcus pneumoniae
, non-typeable
Haemophilus influenzae
, and
Moraxella catarrhalis
were conducted among adults (≥16 years) and children (2 to 15 years) in four rural communities in 2002 and 2004. Infant seven-valent pneumococcal conjugate vaccine (7PCV) with booster 23-valent pneumococcal polysaccharide vaccine was introduced in 2001. Standard microbiological methods were used.
Results
At the time of the 2002 survey, 94% of eligible children had received catch-up pneumococcal vaccination. 324 adults (538 examinations) and 218 children (350 examinations) were enrolled. Pneumococcal carriage prevalence was 26% (95% CI, 22-30) among adults and 67% (95% CI, 62-72) among children. Carriage of non-typeable
H. influenzae
among adults and children was 23% (95% CI, 19-27) and 57% (95% CI, 52-63) respectively and for
M. catarrhalis
, 17% (95% CI, 14-21) and 74% (95% CI, 69-78) respectively. Adult pneumococcal carriage was associated with increasing age (p = 0.0005 test of trend), concurrent carriage of non-typeable
H. influenzae
(Odds ratio [OR] 6.74; 95% CI, 4.06-11.2) or
M. catarrhalis
(OR 3.27; 95% CI, 1.97-5.45), male sex (OR 2.21; 95% CI, 1.31-3.73), rhinorrhoea (OR 1.66; 95% CI, 1.05-2.64), and frequent exposure to outside fires (OR 6.89; 95% CI, 1.87-25.4). Among children, pneumococcal carriage was associated with decreasing age (p < 0.0001 test of trend), and carriage of non-typeable
H. influenzae
(OR 9.34; 95% CI, 4.71-18.5) or
M. catarrhalis
(OR 2.67; 95% CI, 1.34-5.33). Excluding an outbreak of serotype 1 in children, the percentages of serotypes included in 7, 10, and 13PCV were 23%, 23%, and 29% (adults) and 22%, 24%, and 40% (2-15 years). Dominance of serotype 16F, and persistent 19F and 6B carriage three years after initiation of 7PCV is noteworthy.
Conclusions
Population-based carriage of
S. pneumoniae
, non-typeable
H. influenzae
, and
M. catarrhalis
was high in this Australian Aboriginal population. Reducing smoke exposure may reduce pneumococcal carriage. The indirect effects of 10 or 13PCV, above those of 7PCV, among adults in this population may be limited.
Journal Article
L-arginine and Vitamin D Adjunctive Therapies in Pulmonary Tuberculosis: A Randomised, Double-Blind, Placebo-Controlled Trial
2013
Vitamin D (vitD) and L-arginine have important antimycobacterial effects in humans. Adjunctive therapy with these agents has the potential to improve outcomes in active tuberculosis (TB).
In a 4-arm randomised, double-blind, placebo-controlled factorial trial in adults with smear-positive pulmonary tuberculosis (PTB) in Timika, Indonesia, we tested the effect of oral adjunctive vitD 50,000 IU 4-weekly or matching placebo, and L-arginine 6.0 g daily or matching placebo, for 8 weeks, on proportions of participants with negative 4-week sputum culture, and on an 8-week clinical score (weight, FEV1, cough, sputum, haemoptysis). All participants with available endpoints were included in analyses according to the study arm to which they were originally assigned. Adults with new smear-positive PTB were eligible. The trial was registered at ClinicalTrials.gov NCT00677339.
200 participants were enrolled, less than the intended sample size: 50 received L-arginine + active vitD, 49 received L-arginine + placebo vit D, 51 received placebo L-arginine + active vitD and 50 received placebo L-arginine + placebo vitD. According to the factorial model, 99 people received arginine, 101 placebo arginine, 101 vitamin D, 99 placebo vitamin D. Results for the primary endpoints were available in 155 (4-week culture) and 167 (clinical score) participants. Sputum culture conversion was achieved by week 4 in 48/76 (63%) participants in the active L-arginine versus 48/79 (61%) in placebo L-arginine arms (risk difference -3%, 95% CI -19 to 13%), and in 44/75 (59%) in the active vitD versus 52/80 (65%) in the placebo vitD arms (risk difference 7%, 95% CI -9 to 22%). The mean clinical outcome score also did not differ between study arms. There were no effects of the interventions on adverse event rates including hypercalcaemia, or other secondary outcomes.
Neither vitD nor L-arginine supplementation, at the doses administered and with the power attained, affected TB outcomes.
ClinicalTrials.gov. Registry number: NCT00677339.
Journal Article
Azithromycin to prevent acute lower respiratory infections among Australian and New Zealand First Nations and Timorese children (PETAL trial): study protocol for a multicentre, international, double-blind, randomised controlled trial
by
Marsh, Robyn L.
,
Maclennan, Carolyn
,
Schutz, Kobi L
in
Acute Disease
,
Anti-Bacterial Agents - administration & dosage
,
Anti-Bacterial Agents - therapeutic use
2025
IntroductionAcute lower respiratory infections (ALRIs) remain the leading causes of repeated hospitalisations among young disadvantaged Australian and New Zealand First Nations and Timorese children. Severe (hospitalised) and recurrent ALRIs in the first years of life are associated with future chronic lung diseases (eg, bronchiectasis) and impaired lung function. Despite the high burden and long-term consequences of severe ALRIs, clinical, evidence-based and feasible interventions (other than vaccine programmes) that reduce ALRI hospitalisations in children are limited. This randomised controlled trial (RCT) will address this unmet need by trialling a commonly prescribed macrolide antibiotic (azithromycin) for 6–12 months. Long-term azithromycin was chosen as it reduces ALRI rates by 50% in Australian and New Zealand First Nations children with chronic suppurative lung disease or bronchiectasis. The aim of this multicentre, international, double-blind, placebo-containing RCT is to determine whether 6–12 months of weekly azithromycin administered to Australian and New Zealand First Nations and Timorese children after their hospitalisation with an ALRI reduces subsequent ALRIs compared with placebo. Our primary hypothesis is that children receiving long-term azithromycin will have fewer medically attended ALRIs over the intervention period than those receiving placebo.Methods and analysisWe will recruit 160 Australian and New Zealand First Nations and Timorese children aged <2 years to a parallel, superiority RCT across four hospitals from three countries (Australia, New Zealand and Timor-Leste). The primary outcome is the rate of medically attended ALRIs during the intervention period. The secondary outcomes are the rates and proportions of children with ALRI-related hospitalisation, chronic symptoms/signs suggestive of underlying chronic suppurative lung disease or bronchiectasis, serious adverse events, and antimicrobial resistance in the upper airways, and cost-effectiveness analyses.Ethics and disseminationThe Human Research Ethics Committees of the Northern Territory Department of Health and Menzies School of Health Research (Australia), Health and Disability Ethics Committee (New Zealand) and the Institute National of Health-Research Technical Committee (Timor-Leste) approved this study. The study outcomes will be disseminated to academic and medical communities via international peer-reviewed journals and conference presentations, and findings reported to health departments and consumer-based health organisations.Clinical trial registrationAustralia New Zealand Clinical Trial Registry ACTRN12619000456156.
Journal Article
A Single Dose of Azithromycin Does Not Improve Clinical Outcomes of Children Hospitalised with Bronchiolitis: A Randomised, Placebo-Controlled Trial
by
Morris, Peter S.
,
White, Andrew V.
,
Chatfield, Mark D.
in
Anti-Bacterial Agents - therapeutic use
,
Antibiotics
,
Azithromycin
2013
Bronchiolitis, one of the most common reasons for hospitalisation in young children, is particularly problematic in Indigenous children. Macrolides may be beneficial in settings where children have high rates of nasopharyngeal bacterial carriage and frequent prolonged illness. The aim of our double-blind placebo-controlled randomised trial was to determine if a large single dose of azithromycin (compared to placebo) reduced length of stay (LOS), duration of oxygen (O2) and respiratory readmissions within 6 months of children hospitalised with bronchiolitis. We also determined the effect of azithromycin on nasopharyngeal microbiology.
Children aged ≤18 months were randomised to receive a single large dose (30 mg/kg) of either azithromycin or placebo within 24 hrs of hospitalisation. Nasopharyngeal swabs were collected at baseline and 48 hrs later. Primary endpoints (LOS, O2) were monitored every 12 hrs. Hospitalised respiratory readmissions 6-months post discharge was collected.
97 children were randomised (n = 50 azithromycin, n = 47 placebo). Median LOS was similar in both groups; azithromycin = 54 hours, placebo = 58 hours (difference between groups of 4 hours 95%CI -8, 13, p = 0.6). O2 requirement was not significantly different between groups; Azithromycin = 35 hrs; placebo = 42 hrs (difference 7 hours, 95%CI -9, 13, p = 0.7). Number of children re-hospitalised was similar 10 per group (OR = 0.9, 95%CI 0.3, 2, p = 0.8). At least one virus was detected in 74% of children. The azithromycin group had reduced nasopharyngeal bacterial carriage (p = 0.01) but no difference in viral detection at 48 hours.
Although a single dose of azithromycin reduces carriage of bacteria, it is unlikely to be beneficial in reducing LOS, duration of O2 requirement or readmissions in children hospitalised with bronchiolitis. It remains uncertain if an earlier and/or longer duration of azithromycin improves clinical and microbiological outcomes for children. The trial was registered with the Australian and New Zealand Clinical Trials Register. Clinical trials number: ACTRN12608000150347. http://www.anzctr.org.au/TrialSearch.aspx.
Journal Article
Utility of a personalised Bronchiectasis Action Management Plan (BAMP) for children with bronchiectasis: protocol for a multicentre, double-blind parallel, superiority randomised controlled trial
2021
IntroductionBronchiectasis is no longer considered rare or irreversible in children, yet it remains relatively under-researched and neglected in respiratory health globally. Bronchiectasis (including chronic suppurative lung disease) causes substantial morbidity for patients and significant impact on caregivers, especially during acute respiratory exacerbations. In other chronic respiratory diseases (eg, asthma), empowering consumers with an individualised plan for management of acute exacerbations improves clinical outcomes. However, in the absence of any such data specific to bronchiectasis, action management plans are rarely currently used in children or adults with bronchiectasis. We hypothesise that providing an individualised bronchiectasis action management plan (BAMP) to children with bronchiectasis reduces non-scheduled doctor consultations, compared with not having a BAMP.Methods and analysisThis multicentre, parallel, double-blind, randomised trial involving three urban Australian hospitals commenced in June 2018 and will include 198 children, aged <19 years with bronchiectasis who had 2 or more exacerbations in the previous 18 months. Children will be randomised to having an individualised BAMP or standard care (a decoy clinic letter). Primary caregivers will then be followed up monthly for 12 months. The primary outcome is the rate of acute non-scheduled doctor visits for respiratory exacerbations by 12 months. The main secondary outcomes are cough-specific quality of life scores at 6 and 12 months, overall exacerbation rate over 12 months, and proportion of children who received timely influenza vaccination by 30 May annually.Ethics and disseminationThe Human Research Ethics Committees of the Northern Territory Department of Health and Menzies School of Heath Research and Queensland Children’s Hospital approved the study. The results of the trial will be submitted for publication and the BAMP made available free online.Trial registration numberAustralia and New Zealand Clinical Trials Register ACTRN12618000604202.
Journal Article
Longitudinal Nasopharyngeal Carriage and Antibiotic Resistance of Respiratory Bacteria in Indigenous Australian and Alaska Native Children with Bronchiectasis
by
Morris, Peter S.
,
McDonald, Malcolm I.
,
Brown, Ngiare
in
Aboriginal Australians
,
Alaska
,
Amides
2013
Indigenous children in Australia and Alaska have very high rates of chronic suppurative lung disease (CSLD)/bronchiectasis. Antibiotics, including frequent or long-term azithromycin in Australia and short-term beta-lactam therapy in both countries, are often prescribed to treat these patients. In the Bronchiectasis Observational Study we examined over several years the nasopharyngeal carriage and antibiotic resistance of respiratory bacteria in these two PCV7-vaccinated populations.
Indigenous children aged 0.5-8.9 years with CSLD/bronchiectasis from remote Australia (n = 79) and Alaska (n = 41) were enrolled in a prospective cohort study during 2004-8. At scheduled study visits until 2010 antibiotic use in the preceding 2-weeks was recorded and nasopharyngeal swabs collected for culture and antimicrobial susceptibility testing. Analysis of respiratory bacterial carriage and antibiotic resistance was by baseline and final swabs, and total swabs by year.
Streptococcus pneumoniae carriage changed little over time. In contrast, carriage of Haemophilus influenzae declined and Staphylococcus aureus increased (from 0% in 2005-6 to 23% in 2010 in Alaskan children); these changes were associated with increasing age. Moraxella catarrhalis carriage declined significantly in Australian, but not Alaskan, children (from 64% in 2004-6 to 11% in 2010). While beta-lactam antibiotic use was similar in the two cohorts, Australian children received more azithromycin. Macrolide resistance was significantly higher in Australian compared to Alaskan children, while H. influenzae beta-lactam resistance was higher in Alaskan children. Azithromycin use coincided significantly with reduced carriage of S. pneumoniae, H. influenzae and M. catarrhalis, but increased carriage of S. aureus and macrolide-resistant strains of S. pneumoniae and S. aureus (proportion of carriers and all swabs), in a 'cumulative dose-response' relationship.
Over time, similar (possibly age-related) changes in nasopharyngeal bacterial carriage were observed in Australian and Alaskan children with CSLD/bronchiectasis. However, there were also significant frequency-dependent differences in carriage and antibiotic resistance that coincided with azithromycin use.
Journal Article
Randomised controlled trial of perinatal vitamin D supplementation to prevent early-onset acute respiratory infections among Australian First Nations children: the ‘D-Kids’ study protocol
by
Nelson, Jane
,
Licciardi, Paul V
,
Binks, Michael J
in
Australia - epidemiology
,
Babies
,
Bacterial Infection
2023
IntroductionGlobally, acute respiratory infections (ARIs) are a leading cause of childhood morbidity and mortality. While ARI-related mortality is low in Australia, First Nations infants are hospitalised with ARIs up to nine times more often than their non-First Nations counterparts. The gap is widest in the Northern Territory (NT) where rates of both acute and chronic respiratory infection are among the highest reported in the world. Vitamin D deficiency is common among NT First Nations neonates and associated with an increased risk of ARI hospitalisation. We hypothesise that perinatal vitamin D supplementation will reduce the risk of ARI in the first year of life.Methods and analysis‘D-Kids’ is a parallel (1:1), double-blind (allocation concealed), randomised placebo-controlled trial conducted among NT First Nations mother–infant pairs. Pregnant women and their babies (n=314) receive either vitamin D or placebo. Women receive 14 000 IU/week or placebo from 28 to 34 weeks gestation until birth and babies receive 4200 IU/week or placebo from birth until age 4 months. The primary outcome is the incidence of ARI episodes receiving medical attention in the first year of life. Secondary outcomes include circulating vitamin D level and nasal pathogen prevalence. Tertiary outcomes include infant immune cell phenotypes and challenge responses. Blood, nasal swabs, breast milk and saliva are collected longitudinally across four study visits: enrolment, birth, infant age 4 and 12 months. The sample size provides 90% power to detect a 27.5% relative reduction in new ARI episodes between groups.Ethics and disseminationThis trial is approved by the NT Human Research Ethics Committee (2018-3160). Study outcomes will be disseminated to participant families, communities, local policy-makers, the broader research and clinical community via written and oral reports, education workshops, peer-reviewed journals, national and international conferences.Trial registration numberACTRN12618001174279.
Journal Article
Erdosteine in children and adults with bronchiectasis (BETTER trial): study protocol for a multicentre, double-blind, randomised controlled trial
2024
IntroductionBronchiectasis is a worldwide chronic lung disorder where exacerbations are common. It affects people of all ages, but especially Indigenous populations in high-income nations. Despite being a major contributor to chronic lung disease, there are no licensed therapies for bronchiectasis and there remain relatively few randomised controlled trials (RCTs) conducted in children and adults. Our RCT will address some of these unmet needs by evaluating whether the novel mucoactive agent, erdosteine, has a therapeutic role in children and adults with bronchiectasis.Our primary aim is to determine in children and adults aged 2–49 years with bronchiectasis whether regular erdosteine over a 12-month period reduces acute respiratory exacerbations compared with placebo. Our primary hypothesis is that people with bronchiectasis who regularly use erdosteine will have fewer exacerbations than those receiving placebo.Our secondary aims are to determine the effect of the trial medications on quality of life (QoL) and other clinical outcomes (exacerbation duration, time-to-next exacerbation, hospitalisations, lung function, adverse events). We will also assess the cost-effectiveness of the intervention.Methods and analysisWe are undertaking an international multicentre, double-blind, placebo-RCT to evaluate whether 12 months of erdosteine is beneficial for children and adults with bronchiectasis. We will recruit 194 children and adults with bronchiectasis to a parallel, superiority RCT at eight sites across Australia, Malaysia and Philippines. Our primary endpoint is the rate of exacerbations over 12 months. Our main secondary outcomes are QoL, exacerbation duration, time-to-next exacerbation, hospitalisations and lung function.Ethics and disseminationThe Human Research Ethics Committees (HREC) of Children’s Health Queensland (for all Australian sites), University of Malaya Medical Centre (Malaysia) and St. Luke’s Medical Centre (Philippines) approved the study. We will publish the results and share the outcomes with the academic and medical community, funding and relevant patient organisations.Trial registration numberACTRN12621000315819.
Journal Article
Can non‐typeable Haemophilus influenzae carriage surveillance data infer antimicrobial resistance associated with otitis media?
by
Binks, Michael J.
,
Marsh, Robyn L.
,
Morris, Peter S.
in
Antibiotics
,
Antimicrobial agents
,
Antimicrobial resistance
2023
Importance In remote communities of the Northern Territory, Australia, children experience high rates of otitis media (OM), commonly caused by non‐typeable Haemophilus influenzae (NTHi). Few data exist on antibiotic susceptibility of NTHi from OM. Objective To determine whether population‐level nasopharyngeal NTHi antibiotic susceptibility data could inform antibiotic treatment for OM. Methods NTHi isolates (n = 92) collected from ear discharge between 2003 and 2013 were selected to time‐ and age‐match NTHi isolates from the nasopharyngeal carriage (n = 95). Antimicrobial susceptibility were tested. Phylogenomic trees and a genome‐wide association study (GWAS) were performed to determine the similarity of nasopharyngeal and ear isolates at a population level. Results Among 174 NTHi isolates available for antimicrobial susceptibility testing, 10.3% (18/174) were resistant to ampicillin and 9.2% (16/174) were resistant to trimethoprim‐sulfamethoxazole. Small numbers of isolates (≤3) were resistant to tetracycline, chloramphenicol, or amoxicillin‐clavulanic acid. There was no statistical difference in the proportion of ampicillin‐resistant (P = 0.11) or trimethoprim‐sulfamethoxazole‐resistant isolates (P = 0.70) between ear discharge and nasopharynx‐derived NTHi isolates. Three multi‐drug resistant NTHi isolates were identified. Phylogenomic trees showed no clustering of 187 Haemophilus influenzae isolates based on anatomical niche (nasopharynx or ear discharge), and no genetic variations that distinguished NTHi derived from ear discharge and nasopharyngeal carriage were evident in the GWAS. Interpretation In this population‐level study, nasopharyngeal and ear discharge isolates did not represent distinct microbial populations. These results support tracking of population‐level nasopharyngeal NTHi antibiotic resistance patterns to inform clinical management of OM in this population. In remote communities of the Northern Territory, Australia, children have high rates of otitis media, commonly caused by non‐typeable Haemophilus influenzae (NTHi). As the collection of middle ear fluid for culture is not practical for routine healthcare, otitis media is not always diagnosed based on culture results unless the eardrum has perforated. The nasopharynx is a reservoir for NTH, and nasopharyngeal colonization with NTHi is a precursor to otitis media. Therefore, this study aimed to determine whether monitoring the antimicrobial susceptibility of nasopharyngeal isolates could inform treatment guidelines for suppurative otitis media.
Journal Article
Absence of human papillomavirus in nasopharyngeal swabs from infants in a population at high risk of human papillomavirus infection
by
Wurzel, Danielle F
,
Morris, Peter S
,
Tabrizi, Sepehr N.
in
Brief Report
,
Disease
,
Human papillomavirus
2021
Maternal urogenital human papillomavirus (HPV) infection may place neonates at risk of HPV acquisition and subsequently lower respiratory infections as HPV can influence development of immunity. The respiratory HPV prevalence is not known in remote‐dwelling Aboriginal infants, who are at high risk of respiratory infection and where the population prevalence of urogenital HPV in women is high. These data are necessary to inform HPV vaccination regimens. A retrospective analysis using PCR specific for HPV was performed on 64 stored nasopharyngeal swabs from remote‐dwelling Aboriginal infants < 6 months of age, with and without hospitalised pneumonia. HPV DNA was not detected in any specimen. Despite the negative result, we cannot exclude a role for HPV in respiratory infections affecting infants in this population; however, our data do not support HPV as an important contributor to acute respiratory infection in remote‐dwelling Aboriginal children. In populations at high risk of urogenital HPV infection, newborns are at risk of acquiring HPV which may lead to impaired immunity and increased risk of chest infection. In our study, infant nose swabs were HPV negative suggesting that HPV isn’t a common child health issue in this population.
Journal Article