Catherine Satzke, Australia

Murdoch Childrens Research Institute Royal Childrens Hospital

Poster Author Of 2 e-Posters

Author Of 20 Presentations

FACTORS ASSOCIATED WITH PNEUMOCOCCAL CARRIAGE IN CHILDREN AND ADULTS IN FIJI, USING FOUR CROSS-SECTIONAL SURVEYS (ID 224)

Abstract

Background

We describe factors associated with pneumococcal nasopharyngeal carriage in Fiji, using data from annual (2012-2015) cross-sectional surveys, pre- and post-introduction of ten-valent pneumococcal conjugate vaccine (PCV10).

Methods

Infants (5-8 weeks), toddlers (12-23 months), children (2-6 years), and their caregivers participated. Pneumococci were detected using lytA qPCR, with molecular serotyping by microarray. We used logistic regression to determine predictors of pneumococcal carriage.

Results

There were 8,109 participants. Pneumococcal carriage was associated with: years post-PCV10 introduction (global P<0.001), indigenous iTaukei ethnicity (aOR 2.74 [95% CI 2.17-3.45] P<0.001); young age (global P<0.001); urban residence (aOR 1.45 [95% CI 1.30-2.57] P<0.001); living with >2 children <5 years (aOR 1.42 [95% CI 1.27-1.59] P<0.001); poverty (aOR 1.44 [95% CI 1.28-1.62] P<0.001); and upper respiratory tract infection symptoms (aOR 1.77 [95% CI 1.57-2.01] P<0.001). Factors associated with PCV10 and non-PCV10 carriage were similar to those associated with overall carriage. Additionally, PCV10 carriage was associated with PCV10 vaccination (0.58 [95% CI 0.41-0.82] P=0.002) and cigarette smoke exposure (aOR 1.21 [95% CI 1.02-1.43] P=0.031, while non-PCV10 carriage was not associated with years post-PCV10 introduction.

Conclusions

Introduction of PCV10 reduced the odds of overall and PCV10 pneumococcal carriage in Fiji. Indigenous iTaukei ethnicity was positively associated with carriage after adjustment for PCV10.

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FIVE YEARS OF PNEUMONIA SURVEILLANCE IN LAO PDR (ID 925)

Abstract

Background

Laos has one of the highest under-five mortality rates in South East Asia, with pneumonia being a leading cause. Hospital-based sentinel site pneumonia surveillance was established at the main tertiary referral hospital in the capital city, Vientiane. We describe the epidemiology of paediatric pneumonia and the detection of potential pathogens from upper respiratory tract samples since PCV13 introduction in 2013.

Methods

From 2013-2019, we enrolled children aged 2-59 months admitted with acute respiratory infection. Oral, throat and nasopharyngeal swabs were taken. Clinical and socioeconomic details were recorded. PCV13 status was recorded from written records. Pneumonia was classified according to the WHO 2013 definition. Multiplex PCR was used to detect respiratory viruses. Pneumococci were detected using lytA qPCR and serotyped using microarray.

Results

1436 were enrolled, of whom 859 had pneumonia. The median age of pneumonia cases were 15 months (IQR 6-21 months), 53.5% had severe pneumonia, 33.5% were hypoxic, and 1.8% died or were discharged unwell. Malnutrition was present in 5.6%. RSV was seasonal and common in young children. PCV13-type carriage declined in vaccinated and under-vaccinated cases.

Conclusions

Childhood pneumonia is a common reason for hospital admission in Laos. There is some evidence of direct and indirect effects of PCV13. RSV is common.

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IMPACT OF A SINGLE DOSE OF PCV10 OR PCV13 ON NASOPHARYNGEAL PNEUMOCOCCAL CARRIAGE IN VIETNAMESE CHILDREN DURING THE FIRST YEAR OF LIFE (ID 696)

Abstract

Background

Reduced-dose schedules of pneumococcal conjugate vaccine (PCV) could increase the accessibility and use of PCV in low and middle-income countries.

Methods

Groups within the Vietnam Pneumococcal Trial II receive PCV10 and PCV13 in a 1+1 schedule at 2 and 12 months of age, or no vaccine. Nasopharyngeal swabs were collected at 6 and 12 months of age to show the impact of the 2-month dose on pneumococcal carriage.

Results

Based on analysis to date of 1152 of 3200 swabs, vaccine-type carriage was low. In unvaccinated participants, PCV10 and PCV13-type carriage were 5.1% and 10.4% at 6 months, and 8.3% and 12.0% at 12 months, respectively. A dose of PCV10 transiently reduced vaccine-type carriage at 6 months of age (3/178 [1.7%] versus 18/355 [5.1%]).

Conclusions

With the exception of the PCV10 group at 6 months of age, both vaccine-type and non-vaccine-type carriage rates were similar among PCV10-vaccinated participants, PCV13-vaccinated participants and unvaccinated controls at 6 and 12 months of age. Based on preliminary data, a single dose of PCV at 2 months of age does not appear to reduce pneumococcal carriage during the first year of life in this population.

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MONITORING PCV13 IMPACT USING NASOPHARYNGEAL CARRIAGE SURVEILLANCE AMONG CHILDREN WITH PNEUMONIA IN MONGOLIA (ID 965)

Abstract

Background

In 2015, Mongolia was among the earliest countries in Asia to introduce PCV. To monitor the impact of PCV13 introduction, we commenced nasopharyngeal carriage surveillance among children with pneumonia 6 months prior to vaccine introduction.

Methods

We recruited children 2-59 months of age presenting with pneumonia to district hospitals and the national Maternal and Child Health hospital in two districts in Ulaanbaatar. Clinical and demographic data, vaccination status and nasopharyngeal swabs were collected. A random sample of swabs were selected for testing each month. Samples were examined by lytA qPCR, with positives serotyped by microarray.

Results

We recruited 4980 children and tested 983 children from November 2015 to April 2018. The median age was 1.27 and 25.81% of cases were vaccinated in the first and second year following PCV13 introduction, respectively. 474 and 48.22% had received antibiotics in the 48 hours before admission.

Conclusions

Following PCV13 introduction in Mongolia, the prevalence of pneumococcal carriage remained stable while the prevalence of PCV13-type carriage decreased among children with pneumonia. Reductions in PCV13 carriage likely correspond to reductions in disease due to PCV13 types, since carriage is a precursor for disease.

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HIGH RATES OF MULTIPLE NASOPHARYNGEAL PNEUMOCOCCAL CARRIAGE IN CHILDREN WITH PNEUMONIA IN PAPUA NEW GUINEA FOLLOWING PNEUMOCOCCAL CONJUGATE VACCINE INTRODUCTION (ID 731)

Abstract

Background

Pneumococcal carriage rates in Papua New Guinean (PNG) children are among the highest globally. One aim of the multi-site PneuCAPTIVE study is to determine the impact of PCV13 (introduced in 2014) on nasopharyngeal carriage in PNG.

Methods

Nasopharyngeal (NP) swabs and blood were collected from children aged <5 years with moderate or severe pneumonia, and/or suspected meningitis at Eastern Highlands Provincial Hospital or outpatient clinics in Goroka (2016-2018). Pneumococci were identified and quantified by lytA qPCR, and serotyped by microarray. IPD was identified by standard blood culture.

Results

PCV13 coverage was 62%. 1043 were enrolled: 90% had pneumococcal carriage, with median density of 6.59 log10 genome equivalents (GE)/ml (IQR 6.00-7.11). Serotype data were available on 914 cases: 37% were PCV13-types; and 55% had multiple pneumococcal-type carriage. 74 different serotypes and genetic lineages of acapsular pneumococci were identified, the most common being acapsular lineage NT2>19A>15B/C>16F>14. PCV13-type carriage was 28% in vaccinated children vs 46% in unvaccinated children. IPD was confirmed in 7 cases (vaccinated – serotype 1; unvaccinated – serotypes 2, 6B, 15F, 19A, 23A, 29): 4/7 carried the homologous serotype.

Conclusions

There is some evidence of PCV13 being effective against PCV13-types but the high diversity of serotypes in PNG warrants extended valency vaccines.

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SYNERGISTIC AND ANTAGONISTIC INTERACTIONS BETWEEN STREPTOCOCCUS PNEUMONIAE AND RESPIRATORY SYNCYTIAL VIRUS IN AN INFANT MOUSE MODEL (ID 164)

NASOPHARYNGEAL PNEUMOCOCCAL DENSITY IS ASSOCIATED WITH SEVERE PNEUMONIA IN YOUNG CHILDREN IN LAO PDR (ID 856)

Abstract

Background

Pneumococcal nasopharyngeal colonisation density >6.9 log10 copies/mL is associated with primary endpoint pneumonia, very severe pneumonia and hypoxic pneumonia. Few studies have explored the association between pneumococcal density and severe pneumonia. We determined the association between nasopharyngeal pneumococcal density and children with severe pneumonia in Laos.

Methods

A prospective observational study was conducted at Mahosot Hospital. Children <5 years of age admitted with ARI were recruited (2014 to mid-2018). Clinical and demographic data were collected alongside with nasopharyngeal swabs. Severe pneumonia was classified according to the WHO 2013 definition. Pneumococci were detected and quantified by lytA qPCR. A logistic regression model deterimined the association between pneumococcal density and severe pneumonia, after adjusting for potential confounders.

Results

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Of 1,289 participants enrolled, 32.2% had severe pneumonia. After adjusting for potential confounders (age, ethnicity, residential location, living with children <5 years, exposure to cigarette smoke, monthly income, PCV13 vaccination status and co-detection of RSV), pneumococcal density was positively associated with severe pneumonia (adjusted odds ratio 1.4; 95% CI 1.1–1.8; p=0.019).

Conclusions

Pneumococcal carriage density is associated with the probability of severe pneumonia in children in this setting.

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CHARACTERISATION OF A PHAGE-INDUCIBLE CHROMOSOMAL ISLAND IN PNEUMOCOCCAL NASOPHARYNGEAL STRAINS FROM A LONG-TERM CARRAIGE EPISODE (ID 165)

COMMUNICATING PCV13 IMPACT RESULTS IN LAO PDR, USING A MULTIMEDIA APPROACH (ID 690)

Abstract

Background

In 2013, Lao PDR introduced PCV13 with Gavi support. WHO requested a PCV13 impact evaluation as the Ministry of Health required evidence of PCV13 impact. Our project included a variety of community and hospital-based carriage and disease studies.

Methods

We partnered with Lao Ministry of Health and WHO, the key end-users, from the outset. We performed high quality research by collaborating with established international research institutions in Laos, the Lao Oxford Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU) and the leading Lao medical university, The University of Health Sciences, to undertake the research. We developed an infographic and a video of the results.

Results

We disseminated our results to immunisation policy makers at the Lao Ministry of Health, WHO (Laos office and Geneva) and our funders, Gavi, the Vaccine Alliance, and the Bill & Melinda Gates Foundation. Our results were presented to the Lao paediatricians and NITAG members; and at various local, regional and international conferences. The Laos Minister of Health presented the findings to the Gavi Board. The video and infographic were launched on social media and hosted on our institutions’ (MCRI and University of Melbourne) webpage, to coincide with World Pneumonia Day.

Conclusions

This multipronged approach ensured wide dissemination of findings.

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