Paul N. Newton, United Kingdom

University of Oxford Centre for Tropical Medicine and Global Health

Poster Author Of 1 e-Poster

Author Of 7 Presentations

PNEUMOCOCCAL CONJUGATE VACCINE IS EFFECTIVENESS AGAINST HYPOXIC PNEUMONIA IN LAOS, MONGOLIA AND PAPUA NEW GUINEA: A NOVEL CASE-CONTROL VARIANT STUDY (ID 852)

Abstract

Background

We describe a novel approach to determine PCV13 effectiveness (VE) against hypoxic pneumonia in children admitted with pneumonia in Lao PDR (Laos), Mongolia and Papua New Guinea (PNG).

Methods

A 3-5 year prospective hospital-based observational study of children <59 months admitted with pneumonia was undertaken. Pneumonia was defined using the 2013 WHO definition. Hypoxia was defined as an oxygen saturation <90% in room air or requiring oxygen supplementation during hospitalisation. PCV13 status was determined by written record. VE was calculated using logistic regression comparing the odds of hypoxia between vaccinated and undervaccinated pneumonia cases. To handle potential confounders a propensity score (PS) analysis using inverse probability of treatment weighting (IPW) was used. In Laos, multiple imputation (MI) analysis was undertaken for missing data.

Results

The VE against hypoxic pneumonia were: in Laos, unadjusted 23% (95% CI: -9, 46%; p=0·14), PS adjusted IPW 37% (6, 57%; p=0·02), MI adjusted 35% (7, 55%; p=0·02); in Mongolia, unadjusted 33% (26, 40%; p<0.001), PS adjusted IPW 33% (16, 47%; p<0.001); and in PNG, unadjusted 6% (-15, 24%; p=0.532), PS adjusted IPW 36% (17, 51%; p=0.001).

Conclusions

Our novel approach shows that PCV13 is effective against hypoxic pneumonia. PCV13 will contribute to reducing child mortality.

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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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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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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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