Vaccines for a healthy future: 21st DCVMN Annual General Meeting 2020 report

The Developing Countries Vaccine Manufacturers' Network held its 21st Annual General Meeting virtually in November 2020 given the COVID-19 pandemic. Vaccine manufacturing experts, leaders from local and global public health organizations and multilateral organizations, through diverse presentations, questions and answers, focused on the pandemic and the response of vaccine manufacturers where many are engaged in research and development and production agreements. The pandemic is expanding rapidly which makes the global availability and equitable access to safe and effective COVID-19 vaccines critical. Strategies put in place include the establishment of the Access to COVID-19 Tools Accelerator (ACT-A) within which the COVAX facility aims to distribute 2 billion COVID-19 vaccine doses by the end of 2021, with procurement mechanisms already being established. At the same time, regulatory authorities have emergency use authorizations aimed at the rapid approval of safe and effective vaccines, with a push for harmonization in regulatory approaches being advocated. The Meeting was also apprised of other innovations being developed for vaccines including multi-array patches for easier vaccine application, increased heat stability for mitigating cold chain and storage challenges, the barcoding of primary packaging for enhancing vaccine traceability, and gathering data for decision-making. Over time, these innovations will facilitate the widespread availability and equitable access of vaccines including those addressing epidemics and pandemics. In addition, a number of manufacturers described technologies they have for accelerating vaccine manufacturing and supply globally.Overall, there was agreement that manufacturers from developing countries play a critical role in the global research, development and supply of vaccines for a healthy future, with increasing collaboration and partnering between them a growing strength.     

The impact of COVID-19 on routine pediatric vaccination delivery in Brazil

IntroductionChildhood vaccination rates have decreased significantly during the COVID-19 pandemic. The Brazilian immunization program, Programa Nacional de Imunização (PNI), is a model effort, achieving immunization rates comparable to high-income countries. This study aimed to evaluate the impact of the COVID-19 pandemic in pediatric vaccinations administered by the PNI, as a proxy of adherence to vaccinations during 2020.MethodsData on the number of vaccines administered to children under 10 years of age nationally and in each of Brazil’s five regions were extracted from Brazil’s federal health delivery database. Population adjusted monthly vaccination rates from 2015 through 2019 were determined, and autoregressive integrated moving average (ARIMA) models were used to forecast expected vaccinated rates in 2020. We compared the forecasts to reported vaccine administrations to assess adequacy of pediatric vaccine delivery during the COVID-19 pandemic.ResultsFrom January 2015 to February 2020, the average rate of vaccine administration to children was 53.4 per 100,000. After February 2020, this rate decreased to 50.4, a 9.4% drop compared to 2019 and fell outside of forecasted ranges in December 2020. In Brazil's poorest region, the North, vaccine delivery fell outside of the forecasted ranges earlier in 2020 but subsequently rebounded, meeting expected targets by the end of 2020. However, in Brazil's wealthiest South and Southeast regions, initial vaccine delivery fell and remained well below forecasted rates through the end of 2020.ConclusionIn Brazil, despite a model national pediatric vaccination program with an over 95% national coverage, vaccination rates decreased during the COVID-19 pandemic. Coordinated governmental efforts have ameliorated some of the decrease, but more efforts are needed to ensure continued protection from preventable communicable diseases for children globally.     

全球卫生治理面临的困境、原因及应对：以新型冠状病毒肺炎疫苗实施计划为例

新型冠状病毒肺炎威胁着人民的生命健康和财产安全。新型冠状病毒肺炎疫苗是建立人群免疫屏障、实现疫情全球卫生治理的关键公共品, WHO、全球疫苗免疫联盟和流行病防范创新联盟于2020年创建新型冠状病毒肺炎疫苗实施计划(COVAX), 旨在让世界各国, 尤其是中、低收入国家也能公平接种疫苗。尽管COVAX通过协调全球供应链加速了疫苗的研发, COVAX的有效实施面临着筹资、执行和民众认知等多方面的现实困境, 暴露了全球卫生治理中的诸多问题。本文以COVAX为例, 对全球卫生治理面临的困境进行分析, 并探讨背后的成因, 为全球治理的中国参与提出可行的路径。     

Parental Perspectives on Immunizations: Impact of the COVID-19 Pandemic on Childhood Vaccine Hesitancy

Childhood vaccine hesitancy has been studied extensively before the COVID-19 pandemic. The pandemic presented new barriers to pediatric vaccinations. Furthermore, the development of COVID-19 vaccines has complicated factors underlying vaccine hesitancy. We performed a cross-sectional mobile phone-based survey at Children’s Hospital Los Angeles querying parents regarding perspectives on vaccines before and during the pandemic. Our primary aim was to understand the impact of the pandemic on routine childhood vaccine hesitancy. Secondarily, we examined intent to vaccinate, COVID-19 vaccine hesitancy, and key contributing demographic factors. Among 252 participants, we found overall increased childhood vaccine hesitancy (p?=?0.006), increased risk perception (p?=?0.006), and unchanged vaccine confidence during the COVID-19 pandemic. Increased hesitancy did not translate into decreased intent to vaccinate with routine childhood vaccines or influenza vaccines. During the pandemic, households with higher income (50–99 K, >?100 K) correlated with decreased routine childhood vaccine hesitancy, while Hispanic ethnicity and African American race had increased risk perception. For COVID-19 vaccine hesitancy, households with higher income (>?100 K) correlated with decreased hesitancy, while non-White ethnicity and race had increased risk perception. We found that routine childhood vaccine hesitancy increased during the COVID-19 pandemic, mainly due to increased risk perception. Key contributing demographic factors behind both childhood vaccine hesitancy and COVID-19 vaccine hesitancy included household income and race. Understanding factors behind routine childhood vaccine hesitancy is crucial to maintaining pediatric vaccination rates and promoting vaccine confidence during and after the COVID-19 pandemic.

     

Factors impacting parental uptake of COVID-19 vaccination for U.S. Children ages 5–17

COVID-19 vaccination of U.S. children lags behind adult vaccination, but remains critical in mitigating the pandemic. Using a subset of a nationally representative survey, this study examined factors contributing to parental uptake of COVID-19 vaccine for children ages 12–17 and 5–11, stratified by parental COVID-19 vaccination status. Among vaccinated parents, uptake was higher for 12–17-year-olds (78.6%) than 5–11-year-olds (50.7%); only two unvaccinated parents vaccinated their children. Child influenza vaccination was predictive of uptake for both age groups, while side effect concerns remained significant only for younger children. Although parents were more likely to involve adolescents in vaccine decision-making than younger children, this was not predictive of vaccine uptake. These results highlight the importance of addressing the unique and shared concerns parents have regarding COVID-19 vaccination for children of varying ages. Future work should further explore adolescent/child perspectives of involvement in COVID-19 vaccination decision-making to support developmentally appropriate involvement.     

Uptake of COVID-19 vaccines among healthcare workers and the effect of nudging interventions: A mixed methods study

BackgroundDuring the coronavirus disease (COVID-19) pandemic, vaccination of healthcare workers (HCWs) has a critical role because of their high-risk exposure and being a role model. Therefore, we aimed to investigate vaccine hesitancy and the role of mandatory polymerase chain reaction (PCR) testing and education for vaccine uptake.MethodsWe conducted an explanatory sequential designed observational mixed-methods study, including quantitative and qualitative sections consecutively in two different pandemic hospitals between 15 September 2021 and 1 April 2022. The characteristics of vaccinated and unvaccinated HCWs were compared. The vaccine hesitancy scales were applied, and the effect of nudging, such as mandatory PCR and education, were evaluated. In-depth interviews were performed to investigate the COVID-19 vaccine hesitancy among HCWs according to Health Belief Model.ResultsIn total, 3940 HCWs were included. Vaccine hesitancy was more common among males than females, the ancillary workers than other health professions, and nonmedical departments than other departments. After the mandatory weekly PCR request nudge, 83.33 % (130/156) vaccine-hesitant HCWs were vaccinated, and 8.3 % (13/156) after the small group seminars and mandatory PCR every two days. The rate of COVID-19 vaccination was raised from 95.5 % to 99.67 % (3927/3940). At the end of in-depth interviews (n = 13), the vaccine hesitancy determinants were distrust, fear of uncertainty, immune confidence and spirituality, the media effect, social pressure, and obstinacy.ConclusionsThe nudging interventions such as mandatory PCR testing and small group seminars helped raise the rate of COVID-19 vaccination; the most effective one is mandatory PCR.     

COVID-19 vaccine behaviour among citizens of the Métis Nation of Ontario: A qualitative study

BackgroundThe burden of the current COVID-19 pandemic is not shared equally in Canadian society, with Indigenous Peoples being disproportionately affected. Moreover, there is a lack of research pertaining to vaccination behaviour in Métis communities. This Métis-specific and Métis-led qualitative study endeavours to understand COVID-19 vaccine behaviour among citizens of the Métis Nation of Ontario (MNO).MethodsData was collected via one-on-one interviews. Participants were recruited via the MNO’s existing social media channels. Participants filled out a screening survey indicating their intention to vaccinate against COVID-19 as yes, no, or unsure. Sixteen participants (9 yes, 3 unsure, 4 no) were interviewed. Interviews averaged 30 min, and the questions and probes were developed in collaboration with the MNO. The interviewer received Métis-specific cultural safety training. Interviews were transcribed verbatim and uploaded to NVivo 12.ResultsA deductive analysis using the Social Ecological Model framework (SEM) for vaccine behaviour and two blinded coders was used to understand the data. An additional factor, COVID-19 public health measures, was added to the framework to better capture the experiences of participants during the COVID-19 pandemic. Overall, the factors with the greatest number of coded references included Vaccine roll-out and availability, Organization of the public into priority groups, Public discourse, Interpersonal influences, Interface with health professionals, Knowledge state, Trust, and Vaccine risk perception. Bandwagoning (following others’ behaviour) and Freeloading (perceiving enough people have been vaccinated), both factors of the SEM, were not discussed. Yes, no, and unsure participant groups were compared to understand the influences of each factor based on COVID-19 vaccination intention.ConclusionsMNO citizens COVID-19 vaccine behaviour was negatively and positively influenced by a number of factors. This information will allow the MNO and public health units to better tailor their messaging for COVID-19 vaccine uptake campaigns and future pandemic emergencies.     

Safety of the Fiocruz ChAdOx COVID-19 vaccine used in a mass vaccination campaign in Botucatu,Brazil

IntroductionBrazil has been at the core of the COVID-19 pandemic, with the second-highest death toll worldwide. A mass vaccination campaign was initiated on May 16th, 2021, in Botucatu, Brazil, where two doses of ChadOx1-nCoV19 were offered 12 weeks apart to all 18–60- year-olds. This context offers a unique opportunity to study the vaccine safety during a mass campaign.MethodsThe first and second doses of the vaccine were administered in May and August 2021, respectively. Emergency room (ER) and hospitalization records were obtained from the Hospital das Clínicas da Faculdade de Medicina de Botucatu for six weeks before and six weeks after the first and second doses, from 4 April to 19 September 2021. Diagnoses with COVID-19-related ICD codes were excluded to distinguish any trends resulting from the COVID-19 pandemic. ER and hospital visits during the two time periods were compared, including an ICD code comparison, to identify any changes in disease distributions. Data were scanned for a defined list of Adverse Events of Special Interest (AESIs), as presented by the Safety Platform for Emergency Vaccines.Results and discussionA total of 77,683 and 74,051 subjects received dose 1 and dose 2 of ChadOx1-nCoV19, respectively. Vaccination was well tolerated and not associated with any major safety concerns. Increases in ER visits 1 week following both doses were primarily seen in ICD codes related to non-serious side effects of the vaccine, including vaccination site pain and other local events. The neurological AESIs identified (2 of 3 cases of multiple sclerosis) were relapses of a pre-existing condition. One potentially serious hospitalization event for Bell’s palsy had onset before vaccination with dose 1, in a patient who also had a viral infection of the central nervous system. There was no myocarditis, pericarditis cases, or vaccine-related increases in thromboembolic events.     

Risk-based cost-benefit analysis of alternative vaccines against COVID-19 in Brazil: Coronavac vs. Astrazeneca vs. Pfizer

We propose a probabilistic model to quantify the cost-benefit of mass Vaccination Scenarios (VSs) against COVID-19. Through this approach, we conduct a six-month simulation, from August 31st, 2021 to March 3rd, 2022, of nine VSs, i.e., the three primary vaccine brands in Brazil (CoronaVac, AstraZeneca and Pfizer), each with three different vaccination rates (2nd doses per week). Since each vaccine has different individual-level effectiveness, we measure the population-level benefit as the probability of reaching herd immunity (HI). We quantify and categorize the cost-benefit of VSs through risk graphs that show: (i) monetary cost vs. probability of reaching HI; and (ii) number of new deaths vs. probability of reaching HI. Results show that AstraZeneca has the best cost-benefit when prioritizing acquisition costs, while Pfizer is the most cost-beneficial when prioritizing the number of deaths. This work provides helpful information that can aid public health authorities in Brazil to better plan VSs. Furthermore, our approach is not restricted to Brazil, the COVID-19 pandemic, or the mentioned vaccine brands. Indeed, the method is flexible so that this study can be a valuable reference for future cost-benefit analyses in other countries and pandemics, especially in the early stages of vaccination, when data is scarce and uncertainty is high.     

Parents’ and guardians’ views on the acceptability of a future COVID-19 vaccine: A multi-methods study in England

BackgroundThe availability of a COVID-19 vaccine has been heralded as key to controlling the COVID-19 pandemic. COVID-19 vaccination programme success will rely on public willingness to be vaccinated.MethodsWe used a multi-methods approach - involving an online cross-sectional survey and semi-structured interviews - to investigate parents’ and guardians’ views on the acceptability of a future COVID-19 vaccine. 1252 parents and guardians (aged 16 + years) who reported living in England with a child aged 18 months or under completed the survey. Nineteen survey participants were interviewed.FindingsMost survey participants reported they would likely accept a COVID-19 vaccine for themselves (Definitely 55.8%; Unsure but leaning towards yes 34.3%) and their child/children (Definitely 48.2%; Unsure but leaning towards yes 40.9%). Less than 4% of survey participants reported that they would definitely not accept a COVID-19 vaccine. Survey participants were more likely to accept a COVID-19 vaccine for themselves than their child/children. Participants that self-reported as Black, Asian, Chinese, Mixed or Other ethnicity were almost 3 times more likely to reject a COVID-19 vaccine for themselves and their children than White British, White Irish and White Other participants. Survey participants from lower-income households were also more likely to reject a COVID-19 vaccine. In open-text survey responses and interviews, self-protection from COVID-19 was reported as the main reason for vaccine acceptance. Common concerns identified in open-text responses and interviews were around COVID-19 vaccine safety and effectiveness, mostly prompted by the newness and rapid development of the vaccine.ConclusionInformation on how COVID-19 vaccines are developed and tested, including their safety and efficacy, must be communicated clearly to the public. To prevent inequalities in uptake, it is crucial to understand and address factors that may affect COVID-19 vaccine acceptability in ethnic minority and lower-income groups who are disproportionately affected by COVID-19.     

A national survey of COVID-19 vaccine acceptance in Nigeria

IntroductionThe COVID-19 vaccine is essential to reduce the global impact of the pandemic. Understanding its acceptance is key to Nigeria’s national COVID-19 control strategies.MethodsBetween the 6th and 22nd of January 2021, we conducted a non-probability convenience sampling of 3076 respondents using online and in-person interviews to assess the prevalence and predictors of the COVID-19 vaccine acceptance in Nigeria.FindingsOf the 3076 recruited participants, 74.7% (n = 2300/3076) had tertiary education. The median age group was 30–39 years (35.1%, n = 1097/3076) whereas 31% (n = 952/3076) of all respondents had a monthly income<30,000 Naira (65 USD). The survey results indicated that a wide range of the respondents were in government employment (34.1%, n = 1050/3076). The majority of our study participants (92.2%, n = 2835/3076) believe that COVID-19 is real and not a hoax. Only 27.9% (n = 858/3076) of the study participants have been tested for COVID-19 and 17.8 % (n = 152/858) of the tested respondents were COVID-19 positive by PCR. Half (50.7%; n = 1560/3076) of the study participants were willing to take the vaccine once available. The majority of the respondents (81.1%, n = 2496/3076) were not willing to pay for the vaccine. Only 15.9% (n = 483/3076) of the respondents rated the government’s handling of the pandemic above average. The potential acceptance of the COVID-19 vaccine was significantly affected by the age and the monthly income of the respondents. Respondents older than 60 years old (OR: 3.02, 95% CI: 1.69,5.41; p < 0.001) and those that earn between 250,000–500,000 Naira monthly (OR: 1.38; 95% CI: 1.11,1.70; p < 0.001) were more likely to accept the COVID-19 vaccine respectively. In addition, the respondents’ perception of the existence of the disease (OR: 1.45; 95% CI: 0.99,2.18; p > 0.05), the need for a COVID-19 vaccine (OR: 16; 95% CI: 11.63,22.10; p < 0.001), the willingness to pay (OR: 1.68; 95% CI: 1.39,2.01; p < 0.001) and the rating of the government handling of the pandemic (OR: 2.25; 95% CI: 1.57,3.23; p < 0.001) were critical to the acceptance of the COVID-19 vaccine.InterpretationWith 50.7% vaccine acceptance, Nigeria’s public health policymakers must prioritize and develop strategies that will effectively increase COVID-19 vaccine acceptance across the country with emphasis on trust, transparency and strong leadership.     

Benefit-risk assessment of COVID-19 vaccine,mRNA (Comirnaty) for age 16–29 years

Since authorization of the Pfizer-BioNTech COVID-19 Vaccine, mRNA (Comirnaty), real-world evidence has indicated the vaccines are effective in preventing COVID-19 cases and related hospitalizations and deaths. However, increased cases of myocarditis/pericarditis have been reported in the United States associated with vaccination, particularly in adolescents and young adults. FDA conducted a benefit-risk assessment to determine whether the benefits of vaccination outweigh the risks among various age (16–17, 18–24, 25–29) and sex (M/F) subgroups being considered for approved use of the vaccine. We conducted a simulation study with sensitivity analysis of the benefits and risks of the vaccine across possible pandemic scenarios. The model results show benefits outweigh the risks for all scenarios including the high-risk subgroup, males 16–17 years old. Our worst-case scenario used sex and age subgroup-specific incidences for COVID-19 cases (47–98 per million per day) and hospitalizations (1–4 per million per day) which are the US COVID-19 incidences as of July 10, 2021, vaccine efficacy of 70% against COVID-19 cases and 80% against hospitalization, and unlikely, pessimistic, non-zero vaccine-attributable myocarditis death rate. For males 16–17 years old, the model predicts prevented COVID cases, hospitalizations, ICUs, and deaths of 13577, 127, 41, and 1, respectively; while the predicted ranges for excess myocarditis/pericarditis cases, hospitalizations, and deaths attributable to the vaccine are [98–196], [98–196], and 0, respectively, for the worst-case scenario. Considering the different clinical implications of hospitalization due to COVID-19 infection versus vaccine-attributable myocarditis/pericarditis cases, we determine the benefits still outweigh the risks even for this high-risk subgroup. Our results demonstrate that the benefits of the vaccine outweigh its risks for all age and sex subgroups we analyze in this study. Uncertainties exist in this assessment as both benefits and risks of vaccination may change with the continuing evolution of the pandemic.     

Preferences for a COVID-19 vaccine in Australia

In absence of a COVID-19 vaccine, testing, contact tracing and social restrictions are among the most powerful strategies adopted around the world to slow down the spread of the pandemic. Citizens of most countries are suffering major physical, psychological and economic distress. At this stage, a safe and effective COVID-19 vaccine is the most sustainable option to manage the current pandemic. However, vaccine hesitancy by even a small subset of the population can undermine the success of this strategy.The objective of this research is to investigate the vaccine characteristics that matter the most to Australian citizens and to explore the potential uptake of a COVID-19 vaccine in Australia. Through a stated preference experiment, preferences towards a COVID-19 vaccine of 2136 residents of the Australian states and territories were collected and analysed via a latent class model.Results show that preferences for mild adverse cases, mode of administration, location of administration, price and effectiveness are heterogeneous. Conversely, preferences for immediacy and severe reactions are homogeneous, with respondents preferring a shorter period until vaccine is available and lower instances of severe side effects. The expected uptake of the vaccine is estimated under three different scenarios, with the value of 86% obtained for an average scenario. By calculating individual preferences, the willingness to pay is estimated for immediacy, effectiveness, mild and severe side effects.     

Global production capacity of seasonal and pandemic influenza vaccines in 2019

Vaccines will be an important element in mitigating the impact of an influenza pandemic. While research towards developing universal influenza vaccines is ongoing, the current strategy for vaccine supply in a pandemic relies on seasonal influenza vaccine production to be switched over to pandemic vaccines. Understanding how much vaccine could be produced, in which regions of the world and in what timeframe is critical to informing influenza pandemic preparedness. Through the Global Action Plan for Influenza Vaccines, 2006–2016, WHO promoted an increase in vaccine production capacity and monitors the landscape through periodically surveying influenza vaccine manufacturers. This study compares global capacity for production of influenza vaccines in 2019 with estimates from previous surveys; provides an overview of countries with established production facilities; presents vaccine production by type and manufacturing process; and discusses limitations to these estimates. Results of the current survey show that estimated annual seasonal influenza vaccine production capacity changed little since 2015 increasing from 1.47 billion to 1.48 billion doses with potential maximum annual influenza pandemic vaccine production capacity increasing from 6.37 billion to 8.31 billion doses. However, this figure should be interpreted with caution as it presents a best-case scenario with several assumptions which may impact supply. Further, pandemic vaccines would not be immediately available and could take four to six months for first supplies with several more months needed to reach maximum capacity. A moderate-case scenario is also presented of 4.15 billion doses of pandemic vaccine in 12 months. It is important to note that two doses of pandemic vaccine are likely to be required to elicit an adequate immune response. Continued efforts are needed to ensure the sustainability of this production and to conduct research for vaccines that are faster to produce and more broadly protective taking into account lessons learned from COVID-19 vaccine development.     

Fast deployment of COVID-19 disinfectant from common ethanol of gas stations in Brazil

ObjectivesCoronavirus COVID-19 is spreading very fast in Brazil, requiring innovative strategies for the fast deployment of disinfectants. Panic in population triggered by COVID-19 has caused a shortage of alcohol-based hand sanitizers and disinfectants in many cities of Brazil. Despite the governmental reaction against the outbreak, a risk of shortage of disinfectants still exists. The objective of this research is to investigate an alternative method for the fast deployment of alcohol-based disinfectants to protect the population against COVID-19.Methods and resultsThis research highlights the feasibility of disinfectant production from common ethanol available in Brazilian gas stations, as a last resort. A four-by-one (4:1) ratio of common alcohol diluted in water meets the minimum requirements set by health agencies for the alcoholic concentration of disinfectants. Risks factors on alcohol dilution process are associated with corresponding measures of risk mitigation for public health and safety.Conclusions and perspectivesThis research proposes a process for the production and deployment of ethanol-based disinfectant from gas stations. However, the implementation is not timely possible for the COVID-19 pandemic due to complexities in the productive process. For the post-COVID-19 period, the authors give three perspectives: (a) future investigation of human dermal toxicity of common ethanol, (b) establishment of a program for the ethanol decontamination, and (c) countries such as the US, Sweden, Thailand, and Colombia to rethink their energy policy for the adoption of biofuel E100 (ethanol and water) instead of E85 (blend of ethanol, gasoline, and water), as part of their biodefense strategy.     

Intention to participate in a COVID-19 vaccine clinical trial and to get vaccinated against COVID-19 in France during the pandemic

IntroductionThe world is facing the COVID-19 pandemic. The development of a vaccine is challenging. We aimed to determine the proportion of people who intend to get vaccinated against COVID-19 in France or to participate in a vaccine clinical trial.MethodsWe conducted an anonymous on-line survey from the 26th of March to the 20th of April 2020. Primary endpoints were the intention to get vaccinated against COVID-19 if a vaccine was available or participate in a vaccine clinical trial.ResultsThree thousand two hundred and fifty nine individuals answered the survey; women accounted for 67.4% of the respondents. According to their statements, 2.512 participants (77.6%, 95% CI 76.2–79%) will certainly or probably agree to get vaccinated against COVID-19. Older age, male gender, fear about COVID-19, being a healthcare worker and individual perceived risk were associated with COVID-19 vaccine acceptance. Vaccine hesitancy was associated with a decrease in COVID-19 vaccine acceptance. One thousand and five hundred and fifty respondents (47.6% 95% CI 45.9–49.3%) will certainly or probably agree to participate in a COVID-19 vaccine clinical trial. Older age, male gender, being a healthcare worker and individual perceived risk were associated with potential acceptance to participate in a COVID-19 vaccine clinical trial. Vaccine hesitancy was associated with refusal for participation in a COVID-19 vaccine clinical trial.ConclusionsNearly 75% and 48% of the survey respondents were respectively likely to accept vaccination or participation in a clinical trial against COVID-19. Vaccine hesitancy will be the major barrier to COVID-19 vaccine uptake.     

COVID-19 Vaccine Hesitancy and Its Determinants Among Adults with a History of Tobacco or Marijuana Use

Decreasing COVID-19 vaccine hesitancy is an urgent challenge in the US. This study aimed to examine COVID-19 vaccine hesitancy among U.S. adults with a history of using tobacco products or marijuana. Data were collected online in 2020–2021 including respondents’ willingness to accept a COVID-19 vaccine, factors that may promote vaccine acceptance, and prior history of influenza vaccination. Logistic regression models were conducted to estimate the associations between vaccine hesitancy and demographic characteristics, substance use, the impact of the COVID-19 pandemic, and prior influenza vaccination. Among 387 respondents, 49.1% were willing to receive a COVID-19 vaccine, 26.0% were unwilling, and 24.9% were “not sure.” Blacks, suburban or rural residents, those who lived by themselves or with a family with five members or above, those who were not stressed because of the COVID-19 pandemic were more likely to say “no” to a COVID-19 vaccine. Respondents who never, only once, or during some years received an influenza vaccine were 7.0, 6.2, and 5.2 times more likely to say “no” to a COVID-19 vaccine than respondents who received an influenza vaccination every year or almost every year. The use of cigarettes, e-cigarettes, and marijuana, as well as heavy drinking of alcohol, were not associated with COVID-19 hesitancy. The associations between demographic factors and vaccine hesitancy were roughly similar for COVID-19 and influenza vaccines. Although various demographic groups have different levels of vaccine hesitancy and also have different factors to increase their acceptance, addressing misinformation related to COVID-19 vaccines, particularly concern about the safety of the vaccines is crucial in general.