Pneumococcal disease in Thailand

Outcomes among Thai children with risk conditions hospitalized for pneumococcal disease (invasive or non-bacteraemic pneumonia): A multi-centre, observational study

Objective

To describe the risk condition status and clinical outcomes among Thai children hospitalized with pneumococcal disease.

Methods

In this retrospective analysis, children with invasive pneumococcal disease (IPD) or x-ray-confirmed non-bacteraemic pneumococcal pneumonia (NBPP) were identified from nine hospitals in Thailand between 2010 and 2019. Data on risk factors and outcomes were extracted from medical records.

Results

In total, 413 cases were identified: 319 IPD and 94 NBPP. Overall, 133 (32.2%) patients were admitted to intensive care units and 11/406 (2.7%) died. Twenty-seven percent of IPD cases had at-risk conditions and 15% had high-risk conditions. Most IPD cases (32.9%) occurred in children aged 2-4 years, and most NBPP cases (28.7%) occurred in infants aged 0-11 months. Of 51 Streptococcus pneumoniae isolates collected, 41 (80%) were pneumococcal 13-valent conjugate vaccine serotypes. Only 5.1% of children had received a pneumococcal vaccine.

Conclusions

Most children with IPD and NBPP did not have high-risk or at-risk conditions, while 42% had at-risk or high-risk conditions for pneumococcal disease. Very few children in the cohort had received any type of pneumococcal vaccine. Increasing the availability of pneumococcal conjugate vaccines should be considered to reduce the burden of pneumococcal disease among children in Thailand.

A cost-effectiveness analysis of the 13-valent pneumococcal conjugated vaccine and the 23-valent pneumococcal polysaccharide vaccine among Thai older adult

Introduction

This study aims to assess the economic impact of introducing the 13-valent pneumococcal conjugate vaccine (PCV13) and 23-valent pneumococcal polysaccharide vaccine (PPSV23) to Thai older adult aged ≥ 65  years who are healthy or with chronic health conditions and immunocompromised conditions from a societal perspective in order to introduce the vaccine to Thailand's National Immunization Program for the older adult.

Methods

A Markov model was adopted to simulate the natural history and economic outcomes of invasive pneumococcal diseases using updated published sources and Thai databases. We reported analyses as incremental cost-effectiveness ratios (ICER) in USD per quality-adjusted life year (QALY) gained. In addition, sensitivity analyses and budget impact analyses were conducted.

Results

The base-case analysis of all interventions (no vaccinations [current standard of care in Thailand], PPSV23, and PCV13) showed that PPSV23 was extendedly dominated by PCV13. Among healthy individuals or those with chronic health conditions, ICER for PCV13 was 233.63 USD/QALY; meanwhile, among individuals with immunocompromised conditions, ICER for PCV13 was 627.24 USD/QALY. PCV13 are economical vaccine for all older adult Thai individuals when compared to all interventions.

Conclusions

In the context of Thailand, PCV13 is recommended as the best buy and should be primarily prioritized when both costs and benefits are considered. Also, this model will be beneficial to the two-next generation pneumococcal vaccines implementation in Thailand.

Acute otitis media pneumococcal disease burden and nasopharyngeal colonization in children due to serotypes included and not included in current and new pneumococcal conjugate vaccines

INTRODUCTION

Despite the introduction of effective pneumococcal conjugate vaccines (PCV), Streptococcus pneumoniae remains a major cause of acute otitis media (AOM) worldwide. New, higher valency vaccines that offer broader serotype coverage have been recently developed and others are in development. However, given the capsular serotypes expressed by pneumococci causing AOM, it is unclear to what extent differing or higher valency PCVs will provide additional protection.

AREAS COVERED

We conducted a systematic literature search of the MEDLINE database to identify articles published from January 2016 to September 2021 in 4 low and middle income and 10 high-income countries. We searched PubMed with terms: (Streptococcus pneumoniae) OR pneumococcal AND serotype AND (conjugate vaccine). We evaluated serotype distribution and the actual or projected coverage of pneumococcal serotypes by PCV10 (GlaxoSmithKline), PCV13 (Pfizer), PCV10SII (Serum Institute of India) PCV15 (Merck) and PCV20 (Pfizer).

EXPERT OPINION

Our review highlights the important epidemiological differences in serotype distribution and coverage by existing and higher valency vaccines to protect against AOM in children. These data provide support for further evaluation of serotype-independent vaccines for optimal control of pneumococcal AOM disease worldwide.

Factors influencing acceptance of influenza and pneumococcal vaccinations for patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD), often complicated by influenza or pneumococcus, is a leading cause of mortality worldwide. Vaccinations against influenza and pneumococcus are, but vaccination coverage in Thailand has not been ascertained. This study aimed to determine the determinants of influenza and pneumococcal vaccination acceptance in COPD patients. A cross-sectional study of 210 COPD patients was conducted. Demographics, vaccinations, clinical outcomes (exacerbations and hospitalizations), and pulmonary functions were collected. A total of 134 COPD patients (91.0%male) were eligible for final analysis. Of these, 102 (76.1%) and 59 (44.0%) were vaccinated against influenza and pneumococcus, respectively. The influenza-vaccinated group had a higher rate of pneumococcal vaccination than the influenza-unvaccinated group (57.8% vs 0%, P < .001). Rates of influenza and pneumococcal vaccinations were higher in the pulmonologist group than in the non-pulmonologist group (71.6% vs 31.3%, P < .001 and 91.5% vs 38.7%, P < .001, respectively). By multivariable logistic regression analysis, influenza vaccination coverage was significantly higher among patients with bronchodilator response on pulmonary function testing. Pneumococcal vaccination coverage was significantly higher among patients who were seeing pulmonologists. Reasons for not getting influenza vaccination or pneumococcal vaccination were lack of recommendation, lack of knowledge, and misunderstanding, and in the case of pneumococcal vaccine, the expense. In conclusion, the influenza vaccination coverage in our COPD patients was considered high while the pneumococcal vaccination coverage was considered low. Physicians are advised to recommend and promote pneumococcal vaccination.

Effect of a vegetation fire event ban on hospital visits for respiratory diseases in Upper Northern Thailand

BACKGROUND

Upper Northern Thailand (UNT) has been episodically affected by air pollution from vegetation burning, which causes adverse respiratory health effects. However, no study has evaluated the effect of regulatory actions to prohibit vegetation burning on respiratory morbidity. We examined the effect of a burning ban enforced in May 2016 on hospital visits for respiratory diseases in UNT.

METHODS

This study used data from eight provinces in UNT. Analyses were conducted for January to April of 2014-2016 (before ban enforcement) and January to April of 2017-2018 (after ban enforcement). Particulate matter of 10 microns in diameter or smaller (PM10) concentrations, numbers of satellite fire hotspots and age-standardized rates of hospital visits for respiratory diseases before and after ban enforcement were compared. The effect of the ban on hospital visits for respiratory diseases was evaluated using an interrupted time-series analysis controlled for season-specific temporal trends, day of week, public holiday, temperature, relative humidity, number of hospitals and offset population, with gastrointestinal diseases as a negative control. A meta-analysis was performed to pool province-specific effect estimates.

RESULTS

The daily average PM10 concentration and the number of fire hotspots decreased after ban enforcement in all provinces in UNT, with percent changes ranging from 5.3 to 34.3% and 14.3 to 81.5%, respectively. The adjusted pooled effect estimates of hospital visits for respiratory diseases decreased by 9.1% (95% CI: 5.1, 12.9), whereas a null association was observed for gastrointestinal diseases.

CONCLUSION

The burning ban had a positive impact on both air pollution levels and rates of hospital visits for respiratory diseases in UNT.

Pneumococcal Immunization Strategies for High-Risk Pediatric Populations Worldwide: One Size Does Not Fit All

Despite the significant reduction in pneumococcal disease due to pneumococcal vaccines, protection of vulnerable high-risk individuals, especially pediatric populations, remains a great challenge. In an effort to maximize the protection of high-risk children against pneumococcal disease, a combined schedule that includes both conjugate and polysaccharide vaccines is recommended by several countries in the developed world. On the other hand, middle- and low-income countries do not have in place established policies for pneumococcal immunization of children at risk. Pneumococcal conjugate vaccines, despite their benefits, have several limitations, mainly associated with serotype replacement and the wide range of serotype coverage worldwide. In addition, PPV23-impaired immunogenicity and the hyporesponsiveness effect among populations at risk have been well-documented. Therefore, the added value of continuing to include PPV23 in vaccination schedules for high-risk individuals in the years to come remains to be determined by monitoring whether the replacing/remaining serotypes causing IPD are covered by PPV23 to determine whether its benefits outweigh its limitations. In this review, we aim to describe serotype distribution and vaccine efficacy data on pneumococcal disease in the pre- and post-PCV implementation era among high-risk children in both developed and developing countries, assessing the optimization of current recommendations for their vaccination against pneumococcal disease.