Vaccine breakthrough and the invasion dynamics of SARS-CoV-2 variants

Vaccination provides a powerful tool for mitigating and controlling the COVID-19 pandemic. However, a number of factors reduce these potential benefits. The first problem arises from heterogeneities in vaccine supply and uptake: from global inequities in vaccine distribution, to local variations in uptake derived from vaccine hesitancy. The second complexity is biological: though several COVID-19 vaccines offer substantial protection against infection and disease, 'breakthrough' reinfection of vaccinees (and subsequent retransmission from these individuals) can occur, driven especially by new viral variants. Here, using a simple epidemiological model, we show that the combination of infection of remaining susceptible individuals and breakthrough infections of vaccinees can have significant effects in promoting infection of invading variants, even when vaccination rates are high and onward transmission from vaccinees relatively weak. Elaborations of the model show how heterogeneities in immunity and mixing between vaccinated and unvaccinated sub-populations modulate these effects, underlining the importance of quantifying these variables. Overall, our results indicate that high vaccination coverage still leaves no room for complacency if variants are circulating that can elude immunity, even if this happens at very low rates.

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Social media and vaccine hesitancy

BMJ Global Health ◽

10.1136/bmjgh-2020-004206 ◽

2020 ◽

Vol 5 (10) ◽

pp. e004206

Author(s):

Steven Lloyd Wilson ◽

Charles Wiysonge

Keyword(s):

Social Media ◽

Vaccination Coverage ◽

Vaccine Safety ◽

Two Dimensions ◽

Vaccine Hesitancy ◽

Annual Data ◽

Data Set ◽

Digital Society ◽

Vaccination Rates ◽

Society Project

BackgroundUnderstanding the threat posed by anti-vaccination efforts on social media is critically important with the forth coming need for world wide COVID-19 vaccination programs. We globally evaluate the effect of social media and online foreign disinformation campaigns on vaccination rates and attitudes towards vaccine safety.MethodsWeuse a large-n cross-country regression framework to evaluate the effect ofsocial media on vaccine hesitancy globally. To do so, we operationalize social media usage in two dimensions: the use of it by the public to organize action(using Digital Society Project indicators), and the level of negative lyoriented discourse about vaccines on social media (using a data set of all geocoded tweets in the world from 2018-2019). In addition, we measure the level of foreign-sourced coordinated disinformation operations on social media ineach country (using Digital Society Project indicators). The outcome of vaccine hesitancy is measured in two ways. First, we use polls of what proportion ofthe public per country feels vaccines are unsafe (using Wellcome Global Monitor indicators for 137 countries). Second, we use annual data of actual vaccination rates from the WHO for 166 countries.ResultsWe found the use of social media to organise offline action to be highly predictive of the belief that vaccinations are unsafe, with such beliefs mounting as more organisation occurs on social media. In addition, the prevalence of foreign disinformation is highly statistically and substantively significant in predicting a drop in mean vaccination coverage over time. A 1-point shift upwards in the 5-point disinformation scale is associated with a 2-percentage point drop in mean vaccination coverage year over year. We also found support for the connection of foreign disinformation with negative social media activity about vaccination. The substantive effect of foreign disinformation is to increase the number of negative vaccine tweets by 15% for the median country.ConclusionThere is a significant relationship between organisation on social media and public doubts of vaccine safety. In addition, there is a substantial relationship between foreign disinformation campaigns and declining vaccination coverage.

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Preferences for COVID-19 vaccine distribution strategies in the US: A discrete choice survey

PLoS ONE ◽

10.1371/journal.pone.0256394 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0256394

Author(s):

Ingrid Eshun-Wilson ◽

Aaloke Mody ◽

Khai Hoan Tram ◽

Cory Bradley ◽

Alexander Sheve ◽

...

Keyword(s):

Service Delivery ◽

Discrete Choice ◽

Latent Class ◽

Vaccine Hesitancy ◽

Sampling Weights ◽

Public Health Response ◽

Vaccination Rates ◽

The Public ◽

The Us ◽

Vaccine Distribution

Background The COVID-19 vaccination campaign in the US has been immensely successful in vaccinating those who are receptive, further increases in vaccination rates however will require more innovative approaches to reach those who remain hesitant. Developing vaccination strategies that are modelled on what people want could further increase uptake. Methods and findings To inform COVID-19 vaccine distribution strategies that are aligned with public preferences we conducted a discrete choice experiment among the US public (N = 2,895) between March 15 to March 22, 2021. We applied sampling weights, evaluated mean preferences using mixed logit models, and identified latent class preference subgroups. On average, the public prioritized ease, preferring single to two dose vaccinations (mean preference: -0.29; 95%CI: -0.37 to -0.20), vaccinating once rather than annually (mean preference: -0.79; 95%CI: -0.89 to -0.70) and reducing waiting times at vaccination sites. Vaccine enforcement reduced overall vaccine acceptance (mean preference -0.20; 95%CI: -0.30 to -0.10), with a trend of increasing resistance to enforcement with increasing vaccine hesitancy. Latent class analysis identified four distinct preference phenotypes: the first prioritized inherent “vaccine features” (46.1%), the second were concerned about vaccine “service delivery” (8.8%), a third group desired “social proof” of vaccine safety and were susceptible to enforcement (13.2%), and the fourth group were “indifferent” to vaccine and service delivery features and resisted enforcement (31.9%). Conclusions This study identifies several critical insights for the COVID-19 public health response. First, identifying preference segments is essential to ensure that vaccination services meet the needs of diverse population subgroups. Second, making vaccination easy and promoting autonomy by simplifying services and offering the public choices (where feasible) may increase uptake in those who remain deliberative. And, third vaccine mandates have the potential to increase vaccination rates in susceptible groups but may simultaneously promote control aversion and resistance in those who are most hesitant.

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Strategies that make vaccination easy and promote autonomy could increase COVID-19 vaccination in those who remain hesitant.

10.1101/2021.05.19.21257355 ◽

2021 ◽

Author(s):

Ingrid Eshun-Wilson ◽

Aaloke Mody ◽

Khai Hoan Tram ◽

Cory Bradley ◽

Alexander Scheve ◽

...

Keyword(s):

Waiting Times ◽

Vaccination Campaign ◽

Vaccine Hesitancy ◽

Public Preferences ◽

Black African ◽

Vaccination Rates ◽

The Public ◽

The Us ◽

Vaccine Distribution ◽

Vaccination Campaigns

The COVID-19 vaccination campaign in the US has been immensely successful in vaccinating those who are receptive, further increases in vaccination rates however will require more innovative approaches to reach those who remain hesitant, deliberative or indifferent. Phenomena such empty mass vaccination sites and wasted vaccine doses in some regions suggest that in addition to dispelling misinformation and building trust, developing more person-centered vaccination strategies, that are modelled on what people want could further increase uptake. To inform vaccine distribution strategies that are aligned with public preferences for COVID-19 vaccination campaign features we conducted a survey and discrete choice experiment among a representative sample of 2,895 people in the US, between March 15 and March 22, 2021. We found that on average the public prioritized ease, preferring single to two dose vaccinations, vaccinating once rather than annually and reduced waiting times at vaccination sites - for some these were the primary preference drivers. Vaccine enforcement reduced overall vaccine acceptance, with a trend of increasing control aversion with increasing vaccine hesitancy, particularly among those who were young, Black/African American or Republican. These data suggest that making vaccination easy and promoting autonomy by offering the public choices of vaccination brands and locations may increase uptake, and that vaccine mandates could compromise autonomy and increase control aversion in those who are hesitant - reducing vaccination in such groups and potentially undermining the goals of COVID-19 vaccination campaigns.

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Definition of a novel vaccination pathway in PLWHA: experience of a Southern University Hospital

European Journal of Public Health ◽

10.1093/eurpub/ckaa166.837 ◽

2020 ◽

Vol 30 (Supplement_5) ◽

Author(s):

S D'Amato ◽

G F Pellicanò ◽

C Genovese ◽

F Mazzitelli ◽

G Nunnari ◽

...

Keyword(s):

Infectious Diseases ◽

Vaccination Coverage ◽

Clinical Pathway ◽

Drop Out ◽

University Hospital ◽

Treatment Center ◽

People Living With Hiv ◽

Vaccination Rates ◽

Operating Unit ◽

Hiv Aids

Abstract Background At the end of 2018 across the globe there are ∼37.9 million people with HIV/AIDS also thanks to the use of HAART which led to an increase in life expectancy. The Italy Immunization Plan 2017-19 recommend vaccines to these patients but a protocol still isn't present. Moreover, despite the availability of effective vaccines, coverage remained very low for many reasons including problems with privacy. The objectives of this study were a) the appliance of a shared clinical pathway between the “Immunization Center of Hospital Hygiene Operating Unit” and the “HIV/AIDS Disease Prevention, Diagnosis and Treatment Center of Infectious Diseases Operating Unit” b) the increase in vaccination coverage and the evaluation of side effects. Methods A prospective study was conducted from Oct 2019 to Feb 2020 at the G. Martino University Hospital of Messina. In particular, of the 138 patients followed by the Infectious Diseases OU, after evaluation of their immune status, 62% were enrolled in this study. Following the acquisition of informed consent, we collected socio-anagraphical data and we started the free administration of vaccines by providing an hoc calendar in the Immunization Center. Statistical analysis was performed with R software. Results The sample was represented by 86 patients (74% males and 26% females, 21% foreigners and 79% Italian, mean age=40±13.6 SD). We didn't observe drop out and no differences were observed for local/systemic AEs generally reported. We obtained an increase of vaccination coverage with a total of 74 doses administered for flu (+164%) and 240 for other vaccines (+172%). In particular, we immunized a total of 74% of patients for HPV (2% in 2018), 42% for HAV (28% in 2018), 37% for HBV (28% in 2018), 58% for pneumococcal (21% in 2018), 54% for meningococcal ACWY and B (0% in 2018). Conclusions The undertook clinical pathway showed the relevance of specific management of these patients and the need to increase the vaccination offer. Key messages The immunization in people living with HIV is priority to reduce the risk of infectious disease. It’s important to implement a shared clinical pathway to increase vaccination rates of these patients. The application of the protocol had an high impact in patients' adhesion to vaccination also thanks to the chance of accessing to the service in a comfortable setting and suitable to protect privacy.

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Vaccination Coverage: Vaccine-Related Determinants & Anthropometric Measures in Children Resident in a Rural Community in Nigeria

Current Drug Safety ◽

10.2174/1574886316666211029153212 ◽

2021 ◽

Vol 16 ◽

Author(s):

Iribhogbe Osede Ignis ◽

Sonila Tomini

Keyword(s):

Rural Community ◽

Vaccination Coverage ◽

Sampling Technique ◽

Vaccination Status ◽

Childhood Vaccination ◽

Vaccine Hesitancy ◽

Categorical Variables ◽

Anthropometric Measures ◽

Cross Sectional ◽

Susceptible Population

Background: Vaccination of children has played a significant role in reducing early childhood morbidity and mortality from vaccine-preventable diseases; however, some factors act as deterrents in achieving adequate coverage in this susceptible population. Aims & Objectives: The study, therefore, aimed to identify vaccine-related determinants of childhood vaccination as well as determine the relationship between childhood vaccination status and body weight, height, and a child’s body mass index (BMI). Methods: The study was conducted using a cross-sectional design in which 608 caregiver-child pair was recruited sequentially by using a two-stage sampling technique. Structured questionnaires based on the SAGE vaccine hesitancy model were used to interview the participants. Elicited data was analyzed and categorical variables were presented in tables and charts as frequencies, while a chi-square test was used to test the association between the independent and dependent variables. Pearson’s correlation analysis was also done to determine the correlation between vaccination status and weight, height, and BMI of children. Result: The study showed that vaccination coverage was suboptimal (70.56%) in children and was below the expected target of 80%. Although a few (183, 30.10%) of the respondents claimed they would prevent the vaccination of their children due to the fear of needles, the majority (87.50%) will be willing to accept more vaccine doses for their children if there were no pain. While factors such as the experience of adverse reaction (X2 = 13.22, df = 2, p<0.001), crying from pain (X2 = 11.33, df = 2, p<0.001) and the scientific evidence of safety (X2 = 34.63, df = 2, p<0.001) were significantly associated with a complete vaccination status, vaccination status was positively correlated with the weight (r=0.160, p<0.001), height (r=0.081, p=0.023) and BMI (r=0.214, p<0.001) of children in the rural community. Conclusion: Vaccination uptake and coverage can be significantly improved in children by designing and implementing interventional programs that target pharmaceutical and vaccine-specific factors acting as barriers in these rural communities.

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Antecedents of Vaccine Hesitancy in WEIRD and East Asian Contexts

Frontiers in Psychology ◽

10.3389/fpsyg.2021.747721 ◽

2021 ◽

Vol 12 ◽

Author(s):

Daniel S. Courtney ◽

Ana-Maria Bliuc

Keyword(s):

Public Health ◽

Social Media ◽

Science Communication ◽

East Asian ◽

Vaccine Hesitancy ◽

Mmr Vaccine ◽

Specific Context ◽

Vaccination Rates ◽

Key Factor ◽

Effective Science

Following decreasing vaccination rates over the last two decades, understanding the roots of vaccine hesitancy has become a public health priority. Vaccine hesitancy is linked to scientifically unfounded fears around the MMR vaccine and autism which are often fuelled by misinformation spread on social media. To counteract the effects of misinformation about vaccines and in particular the falling vaccination rates, much research has focused on identifying the antecedents of vaccine hesitancy. As antecedents of vaccine hesitancy are contextually dependent, a one-size-fits-all approach is unlikely to be successful in non-WEIRD (Western, Educated, Industrialised, Rich, and Democratic) populations, and even in certain (non-typical) WEIRD sub-populations. Successful interventions to reduce vaccine hesitancy must be based on understanding of the specific context. To identify potential contextual differences in the antecedents of vaccine hesitancy, we review research from three non-WEIRD populations in East Asia, and three WEIRD sub-populations. We find that regardless of the context, mistrust seems to be the key factor leading to vaccine hesitancy. However, the object of mistrust varies across WEIRD and non-WEIRD populations, and across WEIRD subgroups suggesting that effective science communication must be mindful of these differences.

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From Syphilis to Autism, How the Anti-Vaccination Movement of Today is an Echo of the Past

McGill Journal of Medicine ◽

10.26443/mjm.v19i1.770 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Kayleigh Beaveridge

Keyword(s):

Personal Narratives ◽

World Health ◽

Statistical Characteristics ◽

Vaccine Hesitancy ◽

Vaccine Preventable Diseases ◽

Vaccination Rates ◽

The World ◽

The One ◽

Health Organization ◽

The 19Th Century

Introduction: The anti-vaccination movement has led to decreased vaccination rates and increased vulnerability to vaccine-preventable diseases in the general population. In order to better understand the anti-vaccination movement of today, the anti-vaccination movement that emerged in the 19th century is examined and measured against the one observed in the 20th century. Discussion: Though the population of the 19th and 20th centuries differ in many regards and our knowledge of vaccine and immune mechanisms are far greater; the anti-vaccination movement seen today stands on the same pillars as that of the 1800s with the sentiment of fear at its core. Though the façade of these pillars has been altered to suit the world today, both movements exploited the influence of prominent public figures, maintained false associations with dire vaccine consequences and emphasized these through the use of visual media, repetition and personal narratives. The persistence of the anti-vaccination movement lies largely in the use of personal stories which are more impactful and memorable then the statistical characteristics of scientific study. Conclusion: The pro-vaccination movement must respond to the tactics used by the anti-vaccination movement and create accessible, understandable and equally impactful communication strategies in order to prevent the spread of misinformation and counter the efforts of the current anti-vaccination movement. Relevance: Vaccine hesitancy was listed amongst the top 10 global health threats in 2019 by the World Health Organization. In order to shift the negative rhetoric surrounding vaccines, the anti-vaccination movement of today and its historic roots need to be understood.

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Seroprevalence of anti-SARS-CoV-2 antibodies six months into the vaccination campaign in Geneva, Switzerland

10.1101/2021.08.12.21261929 ◽

2021 ◽

Author(s):

Silvia Stringhini ◽

María-Eugenia Zaballa ◽

Nick Pullen ◽

Javier Perez-Saez ◽

Carlos de Mestral ◽

...

Keyword(s):

Vaccination Campaign ◽

Age Groups ◽

Credible Interval ◽

Population Based ◽

Vaccine Hesitancy ◽

Socioeconomically Disadvantaged ◽

Cross Sectional ◽

Vaccination Rates ◽

Health Measures ◽

Random Samples

Background: Up-to-date seroprevalence estimates are critical to describe the SARS-CoV-2 immune landscape in the population and guide public health measures. We aimed to estimate the seroprevalence of anti-SARS-CoV-2 antibodies 15 months into the COVID-19 pandemic and six months into the vaccination campaign. Methods: We conducted a population-based cross-sectional serosurvey between June 1 and July 7, 2021, recruiting participants from age- and sex-stratified random samples of the general population. We tested participants for anti-SARS-CoV-2 antibodies targeting the spike (S) or nucleocapsid (N) proteins (Roche Elecsys immunoassays). We estimated the anti-SARS-CoV-2 antibodies seroprevalence following vaccination and/or infection (anti-S antibodies), or infection only (anti-N antibodies). Results: We included 3355 individuals, of which 1814 (54.1%) were women, 697 (20.8%) were aged <18 years and 449 (13.4%) were aged ≥65 years, 2161 (64.4%) tested positive for anti-S antibodies, and 906 (27.0%) tested positive for anti-N antibodies. The total seroprevalence of anti-SARS-CoV-2 antibodies was 66.1% (95% credible interval, 64.1-68.0). Considering the presence of anti-N antibodies, we estimated that 29.9% (28.0-31.9) of the population developed antibodies after infection; the rest having developed antibodies only via vaccination. Seroprevalence estimates were similar across sexes, but differed markedly across age groups, being lowest among children aged 0-5 years (20.8% [15.5-26.7]) and highest among older adults aged ≥75 years (93.1% [89.6-96.0]). Seroprevalence of antibodies developed via infection and/or vaccination was higher among participants with a higher educational level. Conclusions: Most adults have developed anti-SARS-CoV-2 antibodies, while most teenagers and children remain vulnerable to infection. As the SARS-CoV-2 Delta variant spreads and vaccination rates stagnate, efforts are needed to address vaccine hesitancy, particularly among younger individuals and socioeconomically disadvantaged groups, and to minimize spread among children.

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Racial/Ethnic Disparities in Influenza Vaccination Coverage Among US Adolescents, 2010-2016

Public Health Reports ◽

10.1177/0033354918805720 ◽

2018 ◽

Vol 133 (6) ◽

pp. 667-676 ◽

Cited By ~ 5

Author(s):

Noah S. Webb ◽

Benjamin Dowd-Arrow ◽

Miles G. Taylor ◽

Amy M. Burdette

Keyword(s):

Influenza Vaccination ◽

Vaccination Coverage ◽

Black Adolescents ◽

Ethnic Disparities ◽

White Adolescents ◽

Hispanic Adolescents ◽

Vaccination Rates ◽

Targeted Interventions ◽

Race Ethnicity ◽

Racial Ethnic

Objective: Although research suggests racial/ethnic disparities in influenza vaccination and mortality rates, few studies have examined racial/ethnic trends among US adolescents. We used national cross-sectional data to determine (1) trends in influenza vaccination rates among non-Hispanic white (hereinafter, white), non-Hispanic black (hereinafter, black), and Hispanic adolescents over time and (2) whether influenza vaccination rates among adolescents varied by race/ethnicity. Methods: We analyzed provider-reported vaccination histories for 2010-2016 from the National Immunization Survey–Teen. We used binary logistic regression models to determine trends in influenza vaccination rates by race/ethnicity for 117 273 adolescents, adjusted for sex, age, health insurance, physician visit in the previous 12 months, vaccination facility type, poverty status, maternal education level, children in the household, maternal marital status, maternal age, and census region of residence. We calculated adjusted probabilities for influenza vaccination for each racial/ethnic group, adjusted for the same demographic characteristics. Results: Compared with white adolescents, Hispanic adolescents had higher odds (adjusted odds ratio [aOR] = 1.11; 95% confidence interval [CI], 1.06-1.16) and black adolescents had lower odds (aOR = 0.95; 95% CI, 0.90-1.00) of vaccination. Compared with white adolescents, Hispanic adolescents had significantly higher adjusted probabilities of vaccination for 2011-2013 (2011: 0.22, P < .001; 2012: 0.23, P < .001; 2013: 0.26, P < .001). Compared with white adolescents, black adolescents had significantly lower probabilities of vaccination for 2016 (2016: 0.21, P < .001). Conclusions: Targeted interventions are needed to improve adolescent influenza vaccination rates and reduce racial/ethnic disparities in adolescent vaccination coverage.

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COVID-19 vaccine hesitancy: shortening the last mile

10.31234/osf.io/xchj6 ◽

2021 ◽

Author(s):

Coralie Chevallier ◽

Anne-Sophie Hacquin ◽

Hugo Mercier

Keyword(s):

Vaccine Hesitancy ◽

Evidence Based ◽

Early Adopters ◽

Vaccination Rates ◽

Last Mile ◽

Communication Campaigns ◽

Second Use

We offer three recommendations to increase COVID-19 vaccination rates. First, use communication campaigns leveraging evidence-based levers and argumentation tools with experts. Second, use behavioral insights to make vaccination more accessible. Third, help early adopters communicate about their decision to be vaccinated to accelerate the emergence of pro-vaccination norms.

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