BackgroundMost reports of influenza vaccine effectiveness consider current-season vaccination only.AimWe evaluated a method to estimate the effect of influenza vaccinations (EIV) considering vaccination history.MethodsWe used a test-negative design with well-documented vaccination history to evaluate the average EIV over eight influenza seasons (2011/12-2018/19; n = 10,356). Modifying effect was considered as difference in effects of vaccination in current and previous seasons and current-season vaccination only. We also explored differences between current-season estimates excluding from the reference category people vaccinated in any of the five previous seasons and estimates without this exclusion or only for one or three previous seasons.ResultsThe EIV was 50%, 45% and 38% in people vaccinated in the current season who had previously received none, one to two and three to five doses, respectively, and it was 30% and 43% for one to two and three to five prior doses only. Vaccination in at least three previous seasons reduced the effect of current-season vaccination by 12 percentage points overall, 31 among outpatients, 22 in 9-65 year-olds, and 23 against influenza B. Including people vaccinated in previous seasons only in the unvaccinated category underestimated EIV by 9 percentage points on average (31% vs 40%). Estimates considering vaccination of three or five previous seasons were similar.ConclusionsVaccine effectiveness studies should consider influenza vaccination in previous seasons, as it can retain effect and is often an effect modifier. Vaccination status in three categories (current season, previous seasons only, unvaccinated) reflects the whole EIV.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8365179PMC
http://dx.doi.org/10.2807/1560-7917.ES.2021.26.32.2001099DOI Listing

Publication Analysis

Top Keywords

previous seasons
28
vaccination
12
influenza vaccination
12
current-season vaccination
12
people vaccinated
12
three previous
12
vaccination history
8
considering vaccination
8
seasons
8
previous
8

Similar Publications

Background: While previous reports characterised global and regional variations in RSV seasonality, less is known about local variations in RSV seasonal characteristics. This study aimed to understand the local-level variations in RSV seasonality and to explore the role of geographical, meteorological, and socio-demographic factors in explaining these variations.

Methods: We conducted a systematic literature review to identify published studies reporting data on local-level RSV season onset, offset, or duration for at least two local sites.

View Article and Find Full Text PDF

Background: Testicular torsion (TT) is a urological emergency requiring prompt intervention to prevent irreversible damage to the testicle.

Objective: This study aims to assess trends in men's TT referrals, diagnostic evaluation through Doppler sonography (DS) scan, symptoms before surgery, orchidectomy rates, and TT laterality in relation to age and seasons of the year.

Methods: This observational retrospective cohort study included all patients treated for TT at King Abdullah University Hospital between 2009 and 2021.

View Article and Find Full Text PDF

Introduction: The innate immune response is an important first checkpoint in the evolution of an infection. Although adaptive immunity is generally considered the immune component that retains antigenic memory, innate immune responses can also be affected by previous stimulations. This study evaluated the impact of vaccination on innate cell activation by TLR7/8 agonist R848, as well as seasonal variations.

View Article and Find Full Text PDF

Objective: Guardian Caps (GCs) have been widely implemented at all levels of American football participation based on laboratory evidence that they may reduce head impact forces. The purpose of this study was to determine if GC use during practice was associated with a lower risk of sport-related concussion (SRC) during practices and games among high school football players.

Methods: Data were collected on 2610 athletes from 41 Wisconsin schools that self-selected into GC or Non-GC cohorts.

View Article and Find Full Text PDF

Introduction: In Mexico, respiratory diseases such as tuberculosis (TB), acute respiratory infections (ARI), pertussis (Pt), and pneumonia-bronchopneumonia (Nemu) represent critical public health challenges that contribute to morbidity and mortality and are exacerbated by socioeconomic factors and the COVID-19 pandemic.

Objective: To evaluate the trends, seasonal patterns, and geographic distribution of major respiratory diseases in Mexico between 2000 and 2020.

Methodology: Data from the National Epidemiologic Surveillance System were analyzed using advanced statistical methods, including Kruskal-Wallis tests, Mann-Whitney analysis, and multivariate analysis, to identify temporal and regional variations.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!