The impact of pneumococcal conjugate vaccines on serotype 19A nasopharyngeal carriage

Impact of industry sponsorship on the quality of systematic reviews of vaccines: a cross-sectional analysis of studies published from 2016 to 2019

BACKGROUND

Systematic reviews (SRs) provide the highest level of evidence and inform evidence-based decision making in health care. Earlier studies found association with industry to be negatively associated with methodological quality of SRs. However, this has not been investigated in SRs on vaccines.

METHODS

We performed a systematic literature search using MEDLINE and EMBASE in March 2020. The results were restricted to those published between 2016 and 2019 with no language restrictions. Study characteristics were extracted by one person and checked by an experienced reviewer. The methodological quality of the SRs was assessed with the AMSTAR 2 tool by multiple reviewers after a calibration exercise was performed. A summary score for each SR was calculated. The Mann-Whitney U test and Fisher's exact test were performed to compare both groups.

RESULTS

Out of 185 SRs that met all inclusion criteria, 27 SRs were industry funded. Those were matched with 30 non-industry funded SRs resulting in a total sample size of 57. The mean AMSTAR 2 summary score across all SRs was 0.49. Overall, the median AMSTAR 2 summary score was higher for the non-industry funded SRs than for the industry-funded SRs (0.62 vs. 0.36; p < .00001). Lower ratings for industry funded SRs were consistent across all but one AMSTAR 2 item, though significantly lower only for three specific items.

CONCLUSION

The methodological quality of SRs in vaccination is comparable to SRs in other fields, while it is still suboptimal. We are not able to provide a satisfactory explanation why industry funded SRs had a lower methodological quality than non-industry funded SRs over recent years. Industry funding is an important indicator of methodological quality for vaccine SRs and should be carefully considered when appraising SR quality.

Pneumococcal carriage in unvaccinated children at the time of vaccine implementation into the national immunization program in Poland

We investigated pneumococcal carriage among unvaccinated children under five years of age at a time when the conjugate polysaccharide vaccine (PCV) was introduced in Poland into the national immunization program (NIP). Paired nasopharyngeal swab (NPS) and saliva samples collected between 2016 and 2020 from n = 394 children were tested with conventional culture and using qPCR. The carriage rate detected by culture was 25.4% (97 of 394), by qPCR 39.1% (155 of 394), and 40.1% (158 of 394) overall. The risk of carriage was significantly elevated among day care center attendees, and during autumn/winter months. Among isolates cultured, the most common serotypes were: 23A, 6B, 15BC, 10A, 11A. The coverage of PCV10 and PCV13 was 23.2% (23 of 99) and 26.3% (26 of 99), respectively. Application of qPCR lead to detection of 168 serotype carriage events, with serogroups 15, 6, 9 and serotype 23A most commonly detected. Although the highest number of carriers was identified by testing NPS with qPCR, saliva significantly contributed to the overall number of detected carriers. Co-carriage of multiple serotypes was detected in 25.3% (40 of 158) of carriers. The results of this study represent a baseline for the future surveillance of effects of pneumococcal vaccines in NIP in Poland.

The broader impacts of otitis media and sequelae for informing economic evaluations of pneumococcal conjugate vaccines

INTRODUCTION

Otitis media (OM) is a common childhood infection. Pneumococcal conjugate vaccines (PCVs) prevent OM episodes, thereby reducing short- and long-term clinical, economic, humanistic, and societal consequences. Most economic evaluations of PCVs focus on direct health gains and cost savings from prevented acute episodes but do not fully account for the broader societal impacts of OM prevention.

AREAS COVERED

This review explores the broader burden of OM on children, caregivers, and society to better inform future economic evaluations of PCVs.

EXPERT OPINION

OM causes a substantial burden to society through long-term sequelae, productivity losses, reduced quality of life for children and caregivers, and contribution to antimicrobial resistance from inappropriate antibiotic use. The effect of PCVs on acute OM has been recognized globally, yet the broader impact has not been consistently quantified, studied, or communicated. Economic evaluations of PCVs must evolve to include broader effects for patients, caregivers, and society from OM prevention. Future PCVs with broader coverage may further reduce OM incidence and antimicrobial resistance, but optimal uptake will depend on increasing the recognition and use of novel frameworks that include broader benefits. Communicating the full value of PCVs to decision makers may result in wider access and positive societal returns.

A systematic literature review of economic evaluations of pneumococcal conjugate vaccines in east and southeast Asia (2006-2019)

INTRODUCTION

Pneumococcal infections can lead to serious invasive diseases such as meningitis, septicemia and pneumonia, as well as milder but more common illnesses such as sinusitis and otitis media. The World Health Organization (WHO) recommends the inclusion of pneumococcal conjugate vaccines (PCVs) in infant National Immunization Program (NIP) programs worldwide. Decision-makers in Asian countries planning to introduce PCVs in their respective NIP will need a comprehensive evidence of effectiveness of PCVs at the population level and economic evidence including cost-effectiveness.

AREAS COVERED

A systematic literature review (from 1/1/2016 to 10/11/2019) of PCVs in East and Southeast Asia to understand (1) the contributing factors to cost-effectiveness results of PCVs and (2) whether gaps in evidence exist suggesting why the region may have yet to implement full NIPs.

EXPERT OPINION

In East and Southeast Asia, vaccination with PCVs was found to significantly reduce the mortality and morbidity of pneumococcal diseases and was cost-effective compared to no vaccination. Study assumptions, specifically vaccine local acquisition, the inclusion or exclusion of indirect effects (serotype replacement and herd effect), cross-protection, and protection against nontypeable haemophilus influenzae and serotype 3, were the main drivers of cost-effectiveness.

Pneumococcal Pneumonia and Invasive Pneumococcal Disease in Those 65 and Older: Rates of Detection, Risk Factors, Vaccine Effectiveness, Hospitalisation and Mortality

Pneumococcal pneumonia (PP) and invasive pneumococcal disease (IPD) are important causes of morbidity and mortality in seniors worldwide. Incidence rates and serious outcomes worsen with increasing frailty, numbers of risk factors and decreasing immune competence with increasing age. Literature reviews in Medline and Embase were performed for pneumococcal disease incidence, risk factors, vaccination rates and effectiveness in the elderly. The introduction of protein-conjugated pneumoccal vaccines (PCV) for children markedly reduced IPD and PP in seniors, but serotypes not included in vaccines and with previously low levels increased. Pneumococcal polysaccharide (PPV23) vaccination does not change nasal and pharyngeal carriage rates. Pneumococcal and influenza vaccination rates in seniors are below guideline levels, especially in older seniors and nursing home staff. Pneumococcal and influenza carriage and vaccination rates of family members, nursing home health care workers and other contacts are unknown. National vaccination programmes are effective in increasing vaccination rates. Detection of IPD and PP initially depend on clinical symptoms and new chest X ray infiltrates and then varies according to the population and laboratory tests used. To understand how seniors and especially older seniors acquire PP and IPD data are needed on pneumococcal disease and carriage rates in family members, carers and contacts. Nursing homes need reconfiguring into small units with air ventilation externally from all rooms to minimise respiratory disease transmission and dedicated staff for each unit to minimise transmision of infectious diseaases.