scholarly journals Effectiveness of COVID-19 vaccines against the B.1.617.2 variant

2021 ◽  
Author(s):  
Jamie Lopez Bernal ◽  
Nick Andrews ◽  
Charlotte Gower ◽  
Eileen Gallagher ◽  
Ruth Simmons ◽  
...  
Keyword(s):  
Vaccine Effectiveness ◽  
Vaccine Uptake ◽  
Vulnerable Groups ◽  
Gene Target ◽  
Symptomatic Disease ◽  
Negative Case ◽  
Notable Increase ◽  
The Uk ◽  
Status Data ◽  
Predominant Strain

Background: The B.1.617.2 COVID-19 variant has contributed to the surge in cases in India and has now been detected across the globe, including a notable increase in cases in the UK. We estimate the effectiveness of the BNT162b2 and ChAdOx1 COVID-19 vaccines against this variant. Methods: A test negative case control design was used to estimate the effectiveness of vaccination against symptomatic disease with both variants over the period that B.1.617.2 began circulating with cases identified based on sequencing and S-gene target status. Data on all symptomatic sequenced cases of COVID-19 in England was used to estimate the proportion of cases with B.1.617.2 compared to the predominant strain (B.1.1.7) by vaccination status. Results: Effectiveness was notably lower after 1 dose of vaccine with B.1.617.2 cases 33.5% (95%CI: 20.6 to 44.3) compared to B.1.1.7 cases 51.1% (95%CI: 47.3 to 54.7) with similar results for both vaccines. With BNT162b2 2 dose effectiveness reduced from 93.4% (95%CI: 90.4 to 95.5) with B.1.1.7 to 87.9% (95%CI: 78.2 to 93.2) with B.1.617.2. With ChAdOx1 2 dose effectiveness reduced from 66.1% (95% CI: 54.0 to 75.0) with B.1.1.7 to 59.8% (95%CI: 28.9 to 77.3) with B.1.617.2. Sequenced cases detected after 1 or 2 doses of vaccination had a higher odds of infection with B.1.617.2 compared to unvaccinated cases (OR 1.40; 95%CI: 1.13-1.75). Conclusions: After 2 doses of either vaccine there were only modest differences in vaccine effectiveness with the B.1.617.2 variant. Absolute differences in vaccine effectiveness were more marked with dose 1. This would support maximising vaccine uptake with two doses among vulnerable groups.

scholarly journals Vaccine effectiveness and duration of protection of Comirnaty, Vaxzevria and Spikevax against mild and severe COVID-19 in the UK

2021 ◽  
Author(s):  
Nick Andrews ◽  
Elise Tessier ◽  
Julia Stowe ◽  
Charlotte Gower ◽  
Freja Kirsebom ◽  
...  
Keyword(s):  
Severe Disease ◽  
Vaccine Effectiveness ◽  
Real World Data ◽  
Post Vaccination ◽  
Symptomatic Disease ◽  
Negative Case ◽  
The Uk ◽  
Comorbidity Status ◽  
Duration Of Protection ◽  
Over Time

Background COVID-19 vaccines have been used for 9 months in the UK. Real world data have demonstrated the vaccines to be highly effective against COVID-19, severe disease and death. Here, we estimate vaccine effectiveness over time since the second dose of Comirnaty, Vaxzevria and Spikevax in England. Methods We used a test-negative case-control design to estimate vaccine effectiveness against symptomatic disease, hospitalisation and mortality by age, comorbidity status and over time after the second dose to investigate waning separately for Alpha and Delta variants. Results Vaccine effectiveness against symptomatic disease peaked in the early weeks after the second dose and then fell to 47.3 (95% CI 45 to 49.6) and 69.7 (95% CI 68.7 to 70.5) by 20+ weeks against the Delta variant for Vaxzevria and Comirnaty, respectively. Waning of vaccine effectiveness was greater for 65+ year-olds compared to 40-64 year-olds. Vaccine effectiveness fell less against hospitalisations to 77.0 (70.3 to 82.3) and 92.7 (90.3 to 94.6) beyond 20 weeks post-vaccination and 78.7 (95% CI 52.7 to 90.4) and 90.4 (95% CI 85.1 to 93.8) against death for Vaxzevria and Comirnaty, respectively. Greater waning was observed among 65+ year-olds in a clinically extremely vulnerable group and 40-64-year olds with underlying medical conditions compared to healthy adults. Conclusions We observed limited waning in vaccine effectiveness against hospitalisation and death more than 20 weeks post-vaccination with Vaxzevria or Comirnaty. Waning was greater in older adults and those in a clinical risk group, suggesting that these individuals should be prioritised for booster doses.

scholarly journals Early effectiveness of COVID-19 vaccination with BNT162b2 mRNA vaccine and ChAdOx1 adenovirus vector vaccine on symptomatic disease, hospitalisations and mortality in older adults in England

2021 ◽  
Author(s):  
Jamie Lopez Bernal ◽  
Nick Andrews ◽  
Charlotte Gower ◽  
Julia Stowe ◽  
Chris Robertson ◽  
...  
Keyword(s):  
Older Adults ◽  
Single Dose ◽  
Lower Risk ◽  
Vaccine Effectiveness ◽  
Symptomatic Disease ◽  
Risk Of Death ◽  
Negative Case ◽  
The Uk ◽  
Underlying Risk

AbstractObjectivesTo estimate the real-world effectiveness of the Pfizer/BioNTech BNT162b2 vaccine and Astrazeneca ChAdOx1 vaccine against Confirmed COVID-19, hospitalisations and deaths. To estimate effectiveness on the UK variant of concern.DesignTest negative case control designSettingCommunity COVID-19 PCR testing in EnglandParticipantsAll adults in England aged 70 years and older (over 7.5 million). All COVID-19 testing in the community among eligible individuals who reported symptoms between 8thDecember 2020 and 19thFebruary 2021 was included in the analysis.InterventionsOne and two doses of BNT162b2 vaccine. One dose of ChAdOx1 vaccine.Main outcome measuresSymptomatic PCR confirmed SARS-CoV-2 infection, hospitalisations and deaths with COVID-19.ResultsIndividuals aged >=80 years vaccinated with BNT162b2 prior to 4thJanuary, had a higher odds of testing positive in the first 9 days after vaccination (odds ratio up to 1.48, 95%CI 1.23-1.77), indicating that those initially targeted had a higher underlying risk of infection. Vaccine effectiveness was therefore estimated relative to the baseline post-vaccination period. Vaccine effects were noted from 10-13 days after vaccination, reaching an effectiveness of 70% (95% CI 59-78%) from 28-34 days, then plateauing. From 14 days after the second dose a vaccine effectiveness of 89% (95%CI: 85-93%) was seen.Individuals aged >=70 years vaccinated from 4thJanuary had a similar underlying risk of COVID-19 to unvaccinated individuals. With BNT162b2, vaccine effectiveness reached 61% (95%CI 51-69%) from 28-34 days after vaccination then plateaued. With the ChAdOx1 vaccine, vaccine effects were seen from 14-20 days after vaccination reaching an effectiveness of 60% (95%CI 41-73%) from 28-34 days and further increasing to 73% (95%CI 27-90%) from day 35 onwards.On top of the protection against symptomatic disease, cases who had been vaccinated with one dose of BNT162b2 had an additional 43% (95%CI 33-52%) lower risk of emergency hospitalisation and an additional 51% (95%CI 37-62%) lower risk of death. Cases who had been vaccinated with one dose of ChAdOx1 had an additional 37% (95% CI 3-59%) lower risk of emergency hospitalisation. There was insufficient follow-up to assess the effect of ChAdOx1 on mortality due to the later rollout of this vaccine. Combined with the effect against symptomatic disease, this indicates that a single dose of either vaccine is approximately 80% effective at preventing hospitalisation and a single dose of BNT162b2 is 85% effective at preventing death with COVID-19.ConclusionVaccination with either a single dose of BNT162b2 or ChAdOx1 COVID-19 vaccination was associated with a significant reduction in symptomatic SARS-CoV2 positive cases in older adults with even greater protection against severe disease. Both vaccines show similar effects. Protection was maintained for the duration of follow-up (>6 weeks). A second dose of BNT162b2 provides further protection against symptomatic disease but second doses of ChAdOx1 have not yet been rolled out in England. There is a clear effect of the vaccines against the UK variant of concern.

scholarly journals Effectiveness of BNT162b2 (Comirnaty, Pfizer-BioNTech) COVID-19 booster vaccine against covid-19 related symptoms in England: test negative case-control study

2021 ◽  
Author(s):  
Nick Andrews ◽  
Julia Stowe ◽  
Freja Kirsebom ◽  
Charlotte Gower ◽  
Mary Ramsay ◽  
...  
Keyword(s):  
Confidence Interval ◽  
Booster Dose ◽  
Secondary Analysis ◽  
Vaccine Dose ◽  
Case Control ◽  
Symptomatic Disease ◽  
Booster Vaccine ◽  
Real World Evidence ◽  
Negative Case ◽  
The Uk

Background In September 2021, the UK Government introduced a booster programme targeting individuals over 50 and those in a clinical risk group. Individuals were offered either a full dose of the BNT162b2 (Comirnaty, Pfizer-BioNTech) vaccine or a half dose of the mRNA-1273 (Spikevax, Moderna) vaccine, irrespective of the vaccine received as the primary course Methods We used a test-negative case-control design to estimate the Vaccine Effectiveness (VE) of the booster dose BNT162b2 (Comirnaty, Pfizer-BioNTech) in those aged over 50 against symptomatic disease in post booster time intervals compared to individuals at least 140 days post a second dose with no booster dose recorded. In a secondary analysis, we also compared to unvaccinated individuals and to the 2 to 6 day period after a booster dose was received. Analyses were stratified by which primary doses had been received and any mixed primary courses were excluded. Results The relative VE estimate in the 14 days after the BNT162b2 (Comirnaty, Pfizer-BioNTech) booster dose, compared to individuals that received a two-dose primary course, was 87.4 (95% confidence interval 84.9-89.4) in those individuals who received two doses ChAdOx1-S (Vaxzevria, AstraZeneca) as a primary course and 84.4 (95% confidence interval 82.8-85.8) in those individuals who received two doses of BNT162b2 (Comirnaty, Pfizer-BioNTech) as a primary course. Using the 2-6 day period post the booster dose as the baseline gave similar results. The absolute VE from 14 days after the booster, using the unvaccinated baseline, was 93.1(95% confidence interval 91.7-94.3) in those with ChAdOx1-S (Vaxzevria, AstraZeneca) as their primary course and 94.0 (93.4-94.6) for BNT162b2 (Comirnaty, Pfizer-BioNTech) as their primary course. Conclusions Our study provides real world evidence of significant increased protection from the booster vaccine dose against symptomatic disease in those aged over 50 year of age irrespective of which primary course was received.

scholarly journals Effectiveness of COVID-19 vaccines against the Omicron (B.1.1.529) variant of concern

2021 ◽  
Author(s):  
Nick Andrews ◽  
Julia Stowe ◽  
Freja Kirsebom ◽  
Samuel Toffa ◽  
Tim Rickeard ◽  
...  
Keyword(s):  
Control Design ◽  
Case Control ◽  
Vaccine Effectiveness ◽  
Post Dose ◽  
Symptomatic Disease ◽  
Primary Immunisation ◽  
Negative Case ◽  
Negative Controls

Abstract Background A rapid increase in cases due to the SARS-CoV-2 Omicron (B.1.1.529) variant in highly vaccinated populations has raised concerns about the effectiveness of current vaccines. Methods We used a test-negative case-control design to estimate vaccine effectiveness (VE) against symptomatic disease caused by the Omicron and Delta variants in England. VE was calculated after primary immunisation with two BNT162b2 or ChAdOx1 doses, and at 2+ weeks following a BNT162b2 booster. Results Between 27 November and 06 December 2021, 581 and 56,439 eligible Omicron and Delta cases respectively were identified. There were 130,867 eligible test-negative controls. There was no effect against Omicron from 15 weeks after two ChAdOx1 doses, while VE after two BNT162b2 doses was 88.0% (95%CI: 65.9 to 95.8%) 2-9 weeks after dose 2, dropping to between 34 and 37% from 15 weeks post dose 2.From two weeks after a BNT162b2 booster, VE increased to 71.4% (95%CI: 41.8 to 86.0%) for ChAdOx1 primary course recipients and 75.5% (95%CI: 56.1 to 86.3%) for BNT162b2 primary course recipients. For cases with Delta, VE was 41.8% (95%CI: 39.4-44.1%) at 25+ weeks after two ChAdOx1 doses, increasing to 93.8% (95%CI: 93.2-94.3%) after a BNT162b2 booster. With a BNT162b2 primary course, VE was 63.5% (95%CI: 61.4 to 65.5%) 25+ weeks after dose 2, increasing to 92.6% (95%CI: 92.0-93.1%) two weeks after the booster. Conclusions Primary immunisation with two BNT162b2 or ChAdOx1 doses provided no or limited protection against symptomatic disease with the Omicron variant. Boosting with BNT162b2 following either primary course significantly increased protection.

scholarly journals Effectiveness of the Pfizer-BioNTech and Oxford-AstraZeneca vaccines on covid-19 related symptoms, hospital admissions, and mortality in older adults in England: test negative case-control study

BMJ ◽  
2021 ◽  
pp. n1088
Author(s):  
Jamie Lopez Bernal ◽  
Nick Andrews ◽  
Charlotte Gower ◽  
Chris Robertson ◽  
Julia Stowe ◽  
...  
Keyword(s):  
Case Control Study ◽  
Case Control ◽  
Vaccine Effectiveness ◽  
Symptomatic Disease ◽  
Emergency Hospital Admission ◽  
Negative Case ◽  
Control Study ◽  
Underlying Risk ◽  
Reduced Risk

Abstract Objective To estimate the real world effectiveness of the Pfizer-BioNTech BNT162b2 and Oxford-AstraZeneca ChAdOx1-S vaccines against confirmed covid-19 symptoms (including the UK variant of concern B.1.1.7), admissions to hospital, and deaths. Design Test negative case-control study. Setting Community testing for covid-19 in England. Participants 156 930 adults aged 70 years and older who reported symptoms of covid-19 between 8 December 2020 and 19 February 2021 and were successfully linked to vaccination data in the National Immunisation Management System. Interventions Vaccination with BNT162b2 or ChAdOx1-S. Main outcome measures Primary outcomes were polymerase chain reaction confirmed symptomatic SARS-CoV-2 infections, admissions to hospital for covid-19, and deaths with covid-19. Results Participants aged 80 years and older vaccinated with BNT162b2 before 4 January 2021 had a higher odds of testing positive for covid-19 in the first nine days after vaccination (odds ratio up to 1.48, 95% confidence interval 1.23 to 1.77), indicating that those initially targeted had a higher underlying risk of infection. Vaccine effectiveness was therefore compared with the baseline post-vaccination period. Vaccine effects were noted 10 to 13 days after vaccination, reaching a vaccine effectiveness of 70% (95% confidence interval 59% to 78%), then plateauing. From 14 days after the second dose a vaccination effectiveness of 89% (85% to 93%) was found compared with the increased baseline risk. Participants aged 70 years and older vaccinated from 4 January (when ChAdOx1-S delivery commenced) had a similar underlying risk of covid-19 to unvaccinated individuals. With BNT162b2, vaccine effectiveness reached 61% (51% to 69%) from 28 to 34 days after vaccination, then plateaued. With ChAdOx1-S, effects were seen from 14 to 20 days after vaccination, reaching an effectiveness of 60% (41% to 73%) from 28 to 34 days, increasing to 73% (27% to 90%) from day 35 onwards. On top of the protection against symptomatic disease, a further 43% (33% to 52%) reduced risk of emergency hospital admission and 51% (37% to 62%) reduced risk of death was observed in those who had received one dose of BNT162b2. Participants who had received one dose of ChAdOx1-S had a further 37% (3% to 59%) reduced risk of emergency hospital admission. Follow-up was insufficient to assess the effect of ChAdOx1-S on mortality. Combined with the effect against symptomatic disease, a single dose of either vaccine was about 80% effective at preventing admission to hospital with covid-19 and a single dose of BNT162b2 was 85% effective at preventing death with covid-19. Conclusion Vaccination with either one dose of BNT162b2 or ChAdOx1-S was associated with a significant reduction in symptomatic covid-19 in older adults, and with further protection against severe disease. Both vaccines showed similar effects. Protection was maintained for the duration of follow-up (>6 weeks). A second dose of BNT162b2 was associated with further protection against symptomatic disease. A clear effect of the vaccines against the B.1.1.7 variant was found.

scholarly journals Adolescent vaccination with BNT162b2 (Comirnaty, Pfizer-BioNTech) vaccine and effectiveness of the first dose against COVID-19: national test-negative case-control study, England

2021 ◽  
Author(s):  
Annabel A Powell ◽  
Freja Kirsebom ◽  
Julia Stowe ◽  
Kelsey McOwat ◽  
Vanessa Saliba ◽  
...  
Keyword(s):  
Vaccine Dose ◽  
Immunisation Programme ◽  
Case Control ◽  
Symptomatic Disease ◽  
Negative Case ◽  
Community Transmission ◽  
Adolescent Vaccination ◽  
The Uk ◽  
National Test ◽  
Control Study

AbstractAdolescents in the UK were recommended to have their first dose of mRNA vaccine during a period of high community transmission due to the highly transmissible Delta variant, followed by a second dose at an extended interval of 8-12 weeks. We used national SARS-CoV-2 testing, vaccination and hospitalisation data to estimate vaccine effectiveness (VE) using a test-negative case-control design, against PCR-confirmed symptomatic COVID-19 in England. VE against symptomatic disease increased to 80% within two weeks of the first dose of BNT162b2 vaccine (higher than in adults aged 18-64 years) and then declines rapidly to 40% within 8 weeks (similar to adults). Early data in 16-17-year-olds also indicate high protection against hospitalisation and a rapid increase in VE against symptomatic COVID-19 after the second dose. Our data highlight the importance of the second vaccine dose for protection against symptomatic COVID-19 and raise important questions about the objectives of an adolescent immunisation programme. If prevention of infection is the primary aim, then regular COVID-19 vaccine boosters will be required.

scholarly journals The development of a digital intervention to increase influenza vaccination amongst pregnant women

2021 ◽  
Vol 7 ◽  
pp. 205520762110121
Author(s):  
Joanne E Parsons ◽  
Katie V Newby ◽  
David P French ◽  
Elizabeth Bailey ◽  
Nadia Inglis
Keyword(s):  
Pregnant Women ◽  
Qualitative Methodology ◽  
Intervention Mapping ◽  
Vaccine Uptake ◽  
Flu Vaccination ◽  
Increased Risk ◽  
Diverse Area ◽  
Seasonal Flu ◽  
Flu Vaccine ◽  
The Uk

Objective Pregnant women and unborn babies are at increased risk of complications from influenza, including pneumonia, yet in the UK, uptake of flu vaccination amongst this population remains <50%. Pregnant women hold beliefs about risks of flu and efficacy of vaccination that consistently predict them to decline vaccination. This study aimed to develop a theory and evidence-based intervention addressing these beliefs to promote flu vaccine uptake. Methods The intervention was developed by behavioural scientists, pregnant women, midwives, clinicians and Public Health professionals, informed by Intervention Mapping. Six predefined steps were performed in line with Intervention Mapping. Results The intervention is an animation addressing beliefs about risks of flu and efficacy of vaccination. Preliminary testing using qualitative methodology indicates the information within the animation is appropriate, and the animation is acceptable to pregnant women. Conclusions This is the first known intervention for pregnant women, aiming to increase flu vaccination through addressing risk and efficacy appraisals. It has been implemented within seasonal flu vaccination campaigns during 2018/19 and 2019/20 within one geographically and ethnically diverse area of the UK.

scholarly journals Predictors of Human Papillomavirus Vaccine uptake or intent among parents of preadolescents and adolescents

2017 ◽  
Vol 7 (6) ◽  
pp. 35 ◽  
Author(s):  
Kimberlee Dayal ◽  
Sarah Robinson ◽  
Jessica Schoening ◽  
Mary Catherine Smith ◽  
Son Chae Kim
Keyword(s):  
Human Papillomavirus ◽  
Hpv Vaccine ◽  
Parental Education ◽  
Hpv Vaccination ◽  
College Education ◽  
Vaccine Effectiveness ◽  
Vaccine Uptake ◽  
Human Papillomavirus Vaccine ◽  
Hpv Knowledge ◽  
Hpv Vaccine Uptake

Aim: The aim of this study was to examine predictors of human papillomavirus (HPV) vaccine uptake or intent among parents of pre-adolescents and adolescents.Methods: A cross-sectional descriptive study was conducted among parents of girls aged 9 to 18 years, visiting two primary care clinics in central Texas from September to November 2015. Pearson’s product-moment correlation procedures and path analyses based on Health Belief Model were performed.Results: Path analysis showed that provider recommendation for HPV vaccination (β = 0.37; p < .001) and perceived HPV vaccine harm (β = -0.48; p < .001) had statistically significant direct effects on HPV vaccine uptake or intent. The perceived HPV vaccine effectiveness was directly influenced by HPV knowledge (β = 0.39; p < .001), empowerment in parent-provider relationships (β = 0.30; p = .006) and parental college education (β = 0.23; p = .039).}Conclusions: Together with parental empowerment fostering an equal partnership with providers, targeted education to improve parental HPV knowledge may convince them of the HPV vaccine effectiveness. This, in turn, may help them put the perceived HPV vaccine harm in proper perspective and allow them to make informed decisions regarding the timely HPV vaccination of their children. Because provider recommendation is one of the most important contributing factors for HPV vaccine uptake or intent, parental education and recommendations from nurses will help reduce the knowledge gaps and empower parents to make the timely decisions to vaccinate their children.

scholarly journals COVID-19 vaccine brand hesitancy and other challenges to vaccination in the Philippines

2022 ◽  
Vol 2 (1) ◽  
pp. e0000165
Author(s):  
Arianna Maever L. Amit ◽  
Veincent Christian F. Pepito ◽  
Lourdes Sumpaico-Tanchanco ◽  
Manuel M. Dayrit
Keyword(s):  
Ecological Model ◽  
The Philippines ◽  
Vaccine Uptake ◽  
Phone Call ◽  
Vulnerable Groups ◽  
Vaccine Hesitancy ◽  
Middle Income ◽  
Political Issues ◽  
Vaccination Uptake ◽  
Vaccine Confidence

Effective and safe COVID-19 vaccines have been developed at a rapid and unprecedented pace to control the spread of the virus, and prevent hospitalisations and deaths. However, COVID-19 vaccine uptake is challenged by vaccine hesitancy and anti-vaccination sentiments, a global shortage of vaccine supply, and inequitable vaccine distribution especially among low- and middle-income countries including the Philippines. In this paper, we explored vaccination narratives and challenges experienced and observed by Filipinos during the early vaccination period. We interviewed 35 individuals from a subsample of 1,599 survey respondents 18 years and older in the Philippines. The interviews were conducted in Filipino, Cebuano, and/or English via online platforms such as Zoom or via phone call. All interviews were recorded, transcribed verbatim, translated, and analysed using inductive content analysis. To highlight the complex reasons for delaying and/or refusing COVID-19 vaccines, we embedded our findings within the social ecological model. Our analysis showed that individual perceptions play a major role in the decision to vaccinate. Such perceptions are shaped by exposure to (mis)information amplified by the media, the community, and the health system. Social networks may either positively or negatively impact vaccination uptake, depending on their views on vaccines. Political issues contribute to vaccine brand hesitancy, resulting in vaccination delays and refusals. Perceptions about the inefficiency and inflexibility of the system also create additional barriers to the vaccine rollout in the country, especially among vulnerable and marginalised groups. Recognising and addressing concerns at all levels are needed to improve COVID-19 vaccination uptake and reach. Strengthening health literacy is a critical tool to combat misinformation that undermines vaccine confidence. Vaccination systems must also consider the needs of marginalised and vulnerable groups to ensure their access to vaccines. In all these efforts to improve vaccine uptake, governments will need to engage with communities to ‘co-create’ solutions.

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