Heidi Smith-Vaughan, Australia

Menzies School of Health Research Child Health Division

Presenter of 1 Presentation

 Conference Calendar

PNEUMOCOCCAL SEROTYPE 3 IN THE NORTHERN TERRITORY: SEVERE DISEASE DESPITE PNEUMOCOCCAL VACCINATION PROGRAMS (ID 905)

Session Name
Population Sciences - Epidemics, Outbreaks and Special Settings
Presenter
Authors

Author Of 8 Presentations

 Conference Calendar

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

Session Name
Vaccines - Impact of Vaccine programs and Serotype Replacement
Presenter
Authors

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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NASOPHARYNGEAL CARRIAGE OF S. PNEUMONIAE IN CHILDREN SEVERE ACUTE MALNUTRITION (SAM) AND/OR PNEUMONIA: PRELIMINARY FINDINGS FROM A SURVEILLANCE PROJECT AT THE DILI NATIONAL HOSPITAL, TIMOR-LESTE (ID 1172)

Session Name
Clinical Sciences - Disease in High-risk Groups
Presenter
Authors

Abstract

Background

Children with SAM have impaired immune function (including mucosal defences) and an increased risk of pneumococcal pneumonia. We evaluated if SAM was associated with increased nasopharyngeal carriage of S. pneumoniae (Spn).

Methods

Pulmaun Saudavel is an ongoing surveillance study of children aged 1-59 months hospitalised with SAM and/or pneumonia in Dili, Timor-Leste, where no pneumococcal conjugate vaccine (PCV) is in use. SAM is defined according to World Health Organization (WHO) criteria. Pneumonia is defined as cough or difficulty breathing and any one of: respiratory rate >50bpm, oxygen saturation <90%, lower chest wall indrawing, or WHO-defined radiological pneumonia. NP swabs are collected after admission and processed according to WHO guidelines.

Results

Of 160 cases enrolled to date, 103 (64%) had pneumonia, 27 (17%) SAM, and 30 (19%) both pneumonia and SAM. Overall NP carriage of Spn was 27% (43/160). There was no difference in carriage between SAM cases (15/57, 26%) and pneumonia-only cases (27/97, 28%). Among children with SAM, those with pneumonia had higher carriage (11/30, 37%) compared to those without pneumonia (4/27, 15%; p=0.08).

Conclusions

Pneumonia is a common complication of SAM and may be associated with increased Spn carriage. PCV use in Timor-Leste is likely to benefit children with SAM.

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PNEUMOCOCCAL SEROTYPE 3 IN THE NORTHERN TERRITORY: SEVERE DISEASE DESPITE PNEUMOCOCCAL VACCINATION PROGRAMS (ID 905)

Session Name
Population Sciences - Epidemics, Outbreaks and Special Settings
Presenter
Authors

TWENTY YEARS OF PAEDIATRIC NASOPHARYNGEAL PNEUMOCOCCAL CARRIAGE IN REMOTE NORTHERN AUSTRALIA; SEROTYPES AND ANTIMICROBIAL RESISTANCE IN CHANGING PCV ERAS (ID 933)

Session Name
Vaccines - Impact of Vaccine programs and Serotype Replacement
Presenter
Authors

Abstract

Background

Invasive pneumococcal disease and otitis media due to pneumococci disproportionately affect remote dwelling First Nations Australian children, driven by nasopharyngeal colonisation by respiratory pathogens in the first weeks of life. Microbiological samples have been collected from surveillance studies and clinical trials since 1996. We aimed to explore trends in nasopharyngeal (NP) pneumococcal carriage over time, and factors associated with serotype distribution and resistance.

Methods

This study collated NP microbiological data from the non-interventional arms of trials and cross-sectional studies. Carriage and serotype-specific rates by age category in the differing conjugate vaccine eras will be described. Hierarchical logistic regression will be used to account for confounders (age, clustering within individuals and communities).

Results

Interim findings from over 9,000 NP swabs from children with a median age of 19 months (range 0-18 years) suggest expected reductions in vaccine type pneumococci, with no significant change in overall carriage rates, replacement by non-vaccine serotypes with persistent low-level carriage of vaccine types. 16F was the most commonly isolated serotype, with 50% non-susceptible to penicillin.

Conclusions

Understanding the impact of PCVs on serotype dynamics and antibiotic non-susceptibility of S.pneumoniae in this remote-dwelling population will strengthen evidence for vaccine policy and ongoing antimicrobial stewardship in the region.

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INTERCHANGEABILITY OF PHID-CV10 AND PCV13 IN PRIMARY COURSE SCHEDULES (ID 204)

Session Name
Vaccines - Pneumococcal Vaccines Development
Presenter
Authors

Abstract

Background

In remote communities of northern Australia, we previously demonstrated that the onset of otitis media (OM) in Aboriginal infants was preceded by acquisition of bacterial pathogens that colonise the nasopharynx (NP) soon after birth. We aimed to determine safety and effectiveness of mixed vaccine schedules against early infection due to non-typeable Haemophilus influenzae and Streptococcus pneumoniae.

Methods

In an open-label controlled trial, we randomised (1:1:1) Aboriginal infants at 28 to 38 days of age, to either Prevenar13™ (P, PCV13) at 2-4-6 months of age (_PPP), Synflorix™ (S, PHiD-CV10) at 2-4-6 months (_SSS), or Synflorix at 1-2-4 months plus Prevenar13 at 6 months (SSSP). Primary outcomes (assessor-blinded) were immunogenicity at 7 months of age against pneumococcal serotypes 3, 6A, and 19A, and protein D (GMCs and proportions of infants with IgG > 0·35 µg/mL or > 100 EL.U/mL, respectively). Secondary immunogenicity outcomes at 2 and 4 months are also reported.

Results

A 4-dose early 1-2-4-6 month combination schedule of Synflorix plus Prevenar13 (SSSP) provided superior overall immune protection against serotypes 3, 6A, 19A, and protein D, compared to standard 3-dose 2-4-6 month schedules (_SSS or _PPP).

Conclusions

These vaccines can be combined safely and effectively within this primary schedule, with no evidence of immune suppression.

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THE EFFECT OF ANTIBIOTIC USE ON NASOPHARYNGEAL CARRIAGE OF S. PNEUMONIAE IN A SURVEILLANCE STUDY OF HOSPITALISED CHILDHOOD PNEUMONIA AND MALNUTRITION IN DILI, TIMOR-LESTE (ID 1029)

Session Name
Clinical Sciences - Diagnosis
Presenter
Authors

Abstract

Background

Hospital-based surveillance of pneumonia is an emerging method for monitoring pneumococcal conjugate vaccine (PCV) effectiveness, especially in low resource settings like Timor-Leste. We assessed the impact of antibiotic use on nasopharyngeal carriage of S. pneumoniae (SPN).

Methods

Pulmaun Saudavel is an ongoing pre-PCV surveillance study of children 1-59 months hospitalised with pneumonia and/or malnutrition. Nasopharyngeal swabs were collected as soon as practical after admission and cultured. Antibiotic exposure was classified as prehospital (by parent report) and in-hospital (from the medical record).

Results

Of 160 cases enrolled between September 2019 and January 2020, 43 (26%) had NP carriage of SPN. Carriage was higher among cases without any antibiotic exposure (15/27, 56%), compared to those with any antibiotic exposure (28/133, 21%; p<0.01). While there was no difference in carriage between those with and without prehospital exposure (24% vs 30%, p=0.39), those with swab collected <12hrs after in-hospital exposure had higher carriage compared to those with swab collected >12hrs (50% vs 19%, p=0.034). This remained significant in a logistic regression adjusted for age and sex (p=0.047).

Conclusions

Antibiotic exposure is associated with reduced NP carriage of SPN. Hospital-based studies should attempt to collect NP swabs within 12 hours of first antibiotic dose.

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HEAD TO HEAD COMPARISONS AT 2, 4, AND 7 MONTHS, FOLLOWING STANDARD AND COMBINED PHID-CV10 AND PCV13 SCHEDULES. (ID 429)

Session Name
Vaccines - Pneumococcal Vaccines Development
Presenter
Authors

Abstract

Background

Australian Aboriginal children are at high risk of early infection withStreptococcus pneumoniae and non-typeable Haemophilus influenzae (NTHi). We evaluated immunogenicity against 10 shared serotypes of a 4-dose combination schedule of PHiD-CV10 at 1-2-4 months plus PCV13 at 6 months, compared with standard 2-4-6 month schedules.

Methods

Infants were allocated (1:1:1) at 28 to 38 days of age, to 3-dose schedules of PCV13 (P) or PHiD-CV10 (S) at 2-4-6 months (_PPP or _SSS), or a combination schedule at 1-2-4-6 months (SSSP). Immunogenicity was measured at 2, 4, and 7 months.

Results

At 2 months the SSSP combination was superior to pre-vaccination (VTs other than 6B, 19F, or 23F). At 4 months SSSP was superior to _PPP (9 VTs) and _SSS (7 VTs), and _SSS was superior to _PPP (8 VTs). At 7 months, SSSP was superior to _PPP (1, 6B, 9V, 19F and 23F) and _SSS (8 VTs), and _PPP was superior to _SSS (8 VTs). OPA supports the SSSP schedule, particularly against 1, 6B, and 23F.

Conclusions

The 1-2-4-6 month schedule (SSSP) was superior at 2, 4, and 7 months of age compared to _SSS or _PPP, particularly for 1, 6B, and 23F at 7 months. At 4 months, _SSS was superior to _PPP.

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COMPARISON OF A 2+1 AND 3+0 SCHEDULE OF PCV10 IN VIETNAM (ID 1035)

Session Name
Vaccines - Pneumococcal Vaccines Development
Presenter
Authors