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Risk of SARS-CoV-2 infection and subsequent hospital admission and death at different time intervals since first dose of COVID-19 vaccine administration, Italy, 27 December 2020 to mid-April 2021
More LessAlberto Mateo-Urdiales , Stefania Spila Alegiani , Massimo Fabiani , Patrizio Pezzotti , Antonietta Filia , Marco Massari , Flavia Riccardo , Marco Tallon , Valeria Proietti , Martina Del Manso , Maria Puopolo , Matteo Spuri , Cristina Morciano , Fortunato (Paolo) D’Ancona , Roberto Da Cas , Serena Battilomo , Antonino Bella , Francesca Menniti-Ippolito , on behalf of the Italian Integrated Surveillance of COVID-19 study group and on behalf of the Italian COVID-19 vaccines registryTo assess the real-world impact of vaccines on COVID-19 related outcomes, we analysed data from over 7 million recipients of at least one COVID-19 vaccine dose in Italy. Taking 0–14 days post-first dose as reference, the SARS-CoV-2 infection risk subsequently decreased, reaching a reduction by 78% (incidence rate ratios (IRR): 0.22; 95% CI: 0.21–0.24) 43–49 days post-first dose. Similarly, hospitalisation and death risks decreased, with 89% (IRR: 0.11; 95% CI: 0.09–0.15) and 93% (IRR: 0.07; 95% CI: 0.04–0.11) reductions 36–42 days post-first dose. Our results support ongoing vaccination campaigns.
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Effectiveness of mRNA COVID-19 vaccines in preventing SARS-CoV-2 infections and COVID-19 hospitalisations and deaths in elderly long-term care facility residents, Spain, weeks 53 2020 to 13 2021
More LessResidents in long-term care facilities (LTCF) experienced a large morbidity and mortality during the COVID-19 pandemic in Spain and were prioritised for early COVID-19 vaccination. We used the screening method and population-based data sources to obtain estimates of mRNA COVID-19 vaccine effectiveness for elderly LTCF residents. The estimates were 71% (95% CI: 56–82%), 88% (95% CI: 75–95%), and 97% (95% CI: 92-99%), against SARS-CoV-2 infections (symptomatic and asymptomatic), and COVID-19 hospitalisations and deaths, respectively.
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Effectiveness of COVID-19 vaccines in preventing SARS-CoV-2 infection and hospitalisation, Navarre, Spain, January to April 2021
More LessCOVID-19 vaccine effectiveness was evaluated in close contacts of cases diagnosed during January–April 2021. Among 20,961 contacts, 7,240 SARS-CoV-2 infections were confirmed, with 5,467 being symptomatic and 559 leading to hospitalisations. Non-brand-specific one and two dose vaccine effectiveness were respectively, 35% (95% confidence interval (CI): 25 to 44) and 66% (95% CI: 57 to 74) against infections, 42% (95% CI: 31 to 52) and 82% (95% CI: 74 to 88) against symptomatic infection, and 72% (95% CI: 47 to 85) and 95% (95% CI: 62 to 99) against COVID-19 hospitalisation. The second dose significantly increased effectiveness. Findings support continuing complete vaccination.
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The potential for vaccination-induced herd immunity against the SARS-CoV-2 B.1.1.7 variant
More LessWe assess the feasibility of reaching the herd immunity threshold against SARS-CoV-2 through vaccination, considering vaccine effectiveness (VE), transmissibility of the virus and the level of pre-existing immunity in populations, as well as their age structure. If highly transmissible variants of concern become dominant in areas with low levels of naturally-acquired immunity and/or in populations with large proportions of < 15 year-olds, control of infection without non-pharmaceutical interventions may only be possible with a VE ≥ 80%, and coverage extended to children.
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Effectiveness of the Comirnaty (BNT162b2, BioNTech/Pfizer) vaccine in preventing SARS-CoV-2 infection among healthcare workers, Treviso province, Veneto region, Italy, 27 December 2020 to 24 March 2021
More LessData on effectiveness of the BioNTech/Pfizer COVID-19 vaccine in real-world settings are limited. In a study of 6,423 healthcare workers in Treviso Province, Italy, we estimated that, within the time intervals of 14–21 days from the first and at least 7 days from the second dose, vaccine effectiveness in preventing SARS-CoV-2 infection was 84% (95% confidence interval (CI): 40–96) and 95% (95% CI: 62–99), respectively. These results could support the ongoing vaccination campaigns by providing evidence for targeted communication.
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National routine adult immunisation programmes among World Health Organization Member States: an assessment of health systems to deploy COVID-19 vaccines
More LessIntroductionAs SARS-CoV-2 disproportionately affects adults, the COVID-19 pandemic vaccine response will rely on adult immunisation infrastructures.
AimTo assess adult immunisation programmes in World Health Organization (WHO) Member States.
MethodsWe evaluated country reports from 2018 on adult immunisation programmes sent to WHO and UNICEF. We described existing programmes and used multivariable regression to identify independent factors associated with having them.
ResultsOf 194 WHO Member States, 120 (62%) reported having at least one adult immunisation programme. The Americas and Europe had the highest proportions of adult immunisation programmes, most commonly for hepatitis B and influenza vaccines (> 47% and > 91% of countries, respectively), while Africa and South-East Asia had the lowest proportions, with < 11% of countries reporting adult immunisation programmes for hepatitis B or influenza vaccines, and none for pneumococcal vaccines. In bivariate analyses, high or upper-middle country income, introduction of new or underused vaccines, having achieved paediatric immunisation coverage goals and meeting National Immunisation Technical Advisory Groups basic functional indicators were significantly associated (p < 0.001) with having an adult immunisation programme. In multivariable analyses, the most strongly associated factor was country income, with high- or upper-middle-income countries significantly more likely to report having an adult immunisation programme (adjusted odds ratio: 19.3; 95% confidence interval: 6.5–57.7).
DiscussionWorldwide, 38% of countries lack adult immunisation programmes. COVID-19 vaccine deployment will require national systems for vaccine storage and handling, delivery and waste management to target adult risk groups. There is a need to strengthen immunisation systems to reach adults with COVID-19 vaccines.
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Robust antibody responses in 70–80-year-olds 3 weeks after the first or second doses of Pfizer/BioNTech COVID-19 vaccine, United Kingdom, January to February 2021
More LessSera were collected from 185 adults aged ≥ 70 years in London to evaluate the immune response to COVID-19 vaccines. A single dose of Pfizer/BioNtech vaccine resulted in > 94% seropositivity after 3 weeks in naïve individuals using the Roche Spike antibody assay, while two doses produced very high spike antibody levels, significantly higher than convalescent sera from mild-to-moderate PCR-confirmed adult cases. Our findings support the United Kingdom’s approach of prioritising the first dose and delaying the second dose of COVID-19 vaccine.
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Acute onset supraclavicular lymphadenopathy coinciding with intramuscular mRNA vaccination against COVID-19 may be related to vaccine injection technique, Spain, January and February 2021
More LessMonitoring adverse reactions following immunisation is essential, particularly for new vaccines such as those against COVID-19. We describe 20 cases of acute onset of a single supraclavicular lymphadenopathy manifesting between 24 h and 9 days after ipsilateral intramuscular administration of an mRNA-based COVID-19 vaccine, referred to our WHO Collaborating Centre for Vaccine Safety. Our results indicate that the swelling of supraclavicular lymph nodes following immunisation may constitute a benign and self-limited condition, related to a higher than recommended injection site.
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Impact of age, ethnicity, sex and prior infection status on immunogenicity following a single dose of the BNT162b2 mRNA COVID-19 vaccine: real-world evidence from healthcare workers, Israel, December 2020 to January 2021
More LessThe BNT162b2 mRNA COVID-19 vaccine showed high efficacy in clinical trials but observational data from populations not included in trials are needed. We describe immunogenicity 21 days post-dose 1 among 514 Israeli healthcare workers by age, ethnicity, sex and prior COVID-19 infection. Immunogenicity was similar by ethnicity and sex but decreased with age. Those with prior infection had antibody titres one magnitude order higher than naïve individuals regardless of the presence of detectable IgG antibodies pre-vaccination.
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Attitudes of healthcare workers towards COVID-19 vaccination: a survey in France and French-speaking parts of Belgium and Canada, 2020
More LessIn October and November 2020, we conducted a survey of 2,678 healthcare workers (HCWs) involved in general population immunisation in France, French-speaking Belgium and Quebec, Canada to assess acceptance of future COVID-19 vaccines (i.e. willingness to receive or recommend these) and its determinants. Of the HCWs, 48.6% (n = 1,302) showed high acceptance, 23.0% (n = 616) moderate acceptance and 28.4% (n = 760) hesitancy/reluctance. Hesitancy was mostly driven by vaccine safety concerns. These must be addressed before/during upcoming vaccination campaigns.
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