Evidence map›Paper›PMID 34424508›Full record

ArticleCanadian journal of public health = Revue canadienne de sante publique2022

Exploring the reasons for low pertussis vaccine effectiveness in Ontario, Canada, 2006-2008: a Canadian Immunization Research Network study.

Stephanie L Hughes, Jeffrey C Kwong, Kevin L Schwartz, Cynthia Chen, Caitlin Johnson, Ye Li, Alex Marchand-Austin, Shelly Bolotin, Frances B Jamieson, Steven J Drews and 4 more

Abstract read
In one paragraph

Article in Canadian journal of public health = Revue canadienne de sante publique, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

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No citing paper in PubMed yet.

4 · The record

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5 · Who and what money

Authors and funding

14 authors.

Stephanie L HughesPublic Health Ontario, Toronto, ON, Canada.
Jeffrey C KwongPublic Health Ontario, Toronto, ON, Canada.
Kevin L SchwartzPublic Health Ontario, Toronto, ON, Canada.
Cynthia ChenPublic Health Ontario, Toronto, ON, Canada.
Caitlin JohnsonPublic Health Ontario, Toronto, ON, Canada.
Ye LiPublic Health Ontario, Toronto, ON, Canada.
Alex Marchand-AustinPublic Health Ontario, Toronto, ON, Canada.
Shelly BolotinPublic Health Ontario, Toronto, ON, Canada.
Frances B JamiesonPublic Health Ontario, Toronto, ON, Canada.
Steven J DrewsCanadian Blood Services, Ottawa, ON, Canada.
Margaret L RussellDepartment of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
Lawrence W SvensonDepartment of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
Salaheddin M MahmudVaccine and Drug Evaluation Centre, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada.
Natasha S CrowcroftDalla Lana School of Public Health, University of Toronto, Toronto, ON, M5T 3M7, Canada. natasha.crowcroft@utoronto.ca.ORCID 0000-0002-6761-8783

Funding

CIHR
6 · The paper itself

Abstract

objectivesAlthough pertussis vaccines have been widely used for many decades, a burden of illness persists. Resurgences in Ontario, Canada, have not been substantial in the past decade, but an outbreak of pertussis occurred in Toronto between 1 October 2005 and 31 March 2006. Previous Ontario studies found high vaccine effectiveness (VE) in the initial years post-immunization. In order to explore the impact of outbreaks and external factors on VE, we investigated pertussis VE during the period 2006-2008.

methodsWe assessed pertussis VE using a frequency-matched case-control study for the period 1 March 2006 to 31 December 2008. We used logistic regression to estimate VE by age, time since last vaccination, and vaccination status according to the Ontario recommended schedule. We compared analyses including and excluding cases from Toronto, and to two recent Ontario pertussis VE studies.

resultsWe included 1797 confirmed cases and 7188 matched controls. Most cases were under 4 years of age during the study period. Pertussis VE was 3.8% (95% CI: - 21.0, 24.0) in the period 15-364 days following the last pertussis vaccine dose, and increased with increasing time since vaccination. Pertussis VE in the first 15-364 days excluding Toronto increased to 57.1% (95% CI: 26.0, 75.1), but the trend of increasing VE with time since vaccination persisted. Although VE was higher in older (6-11 years) than younger (0-5 years) children, it was lower at 12-13 years than after 14 years.

conclusionVE was lower in comparison with other studies conducted in Ontario, particularly in younger children. Various factors occurring during the study period may have influenced the results, including clinical testing of asymptomatic contacts, laboratory testing and methods and reporting practice, and a sensitive case definition. Further studies are needed to optimize methods for measuring VE to inform pertussis vaccine policy.

Indexed as

Pertussis VaccineWhooping CoughAgedCase-Control StudiesChildHumansOntarioVaccinationVaccine EfficacyPertussis VaccineBiasCase-control studyPertussisVaccine effectivenessVaccine program evaluationWhooping cough

Identifiers

PMID34424508
PMCPMC8825901

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.