Optimizing Communication on HPV Vaccination to Parents of 11- to 14-Year-Old Adolescents in France: A Discrete Choice Experiment.

BACKGROUND: With the aim to optimize communication during HPV vaccination campaigns in France, we elicited parental preferences around HPV vaccination. METHODS: We conducted a single-profile discrete choice experiment (DCE) among parents of 11- to 14-year-old middle-school pupils, who completed an anonymous, self-administered, internet-based questionnaire during 2020-2021. The DCE comprised five attributes (vaccine-preventable disease, justification of optimal age, information on safety, indirect protection and coverage) of vaccination against an unnamed disease that were presented to respondents in ten choice tasks, or scenarios. We use fixed effect logit models to estimate attribute weights on theoretical vaccine acceptance, and random effect linear regression to estimate attribute coefficients on vaccine eagerness (decision and decision certainty). We estimated marginal effects of attributes on expected vaccine acceptance. RESULTS: Vaccination scenarios were accepted by 55.6-89.2% of the 1291 participants. The largest marginal effects on expected vaccine acceptance in the full sample arose from prevention of cancer versus genital warts (+ 11.3 percentage points); from a "severe side effect suspicion that was not scientifically confirmed" versus a statement about "more benefits than risks" (+ 8.9 percentage points), and information on 80% vaccine coverage in neighbouring countries versus on "insufficient coverage" (+ 4.2 percentage points). Explaining the early age of vaccination by sexual debut had a strong negative impact among French monolingual parents with lower education level (vs age-independent, OR 0.48, 95% CI 0.27-0.86), but not other socio-economic groups. After removing low-quality responses (unvaried certainty and short questionnaire completion), among serial non-demanders with children not vaccinated against HPV, only disease elimination impacted vaccine eagerness positively (coefficient 0.54, 0.06-1.02). DISCUSSION: Using DCEs to elicit parents' preferences around communication messages, notably on cancer prevention, vaccine coverage and information about vaccine safety, could help to optimize HPV vaccination promotion efforts.

Health protective behaviours during the COVID-19 pandemic: Risk adaptation or habituation?

Many epidemiological works show that human behaviours play a fundamental role in the spread of infectious diseases. However, we still do not know much about how people modify their Health Protective Behaviours (HPB), such as hygiene or social distancing measures, over time in response to the health threat during an epidemic. In this study, we examined the role of the epidemiological context in engagement in HPB through two possible mechanisms highlighted by research into decision-making under risk: risk adaptation and risk habituation. These two different mechanisms were assumed to explain to a large extent the temporal variations in the public's responsiveness to the health threat during the COVID-19 pandemic. To test them, we used self-reported data collected through a series of 25 cross-sectional surveys conducted in France among representative samples of the adult population, from March 2020 to September 2021 (N = 50,019). Interestingly, we found that both mechanisms accounted relatively well for the temporal variation in the adoption of social distancing during the pandemic, which is remarkable given their different assumptions about the underlying social cognitive processes involved in response to a health threat. These results suggest that strengthening the incentives to encourage people to maintain health protective behaviours and to counter risk habituation effects is crucial to disease control and prevention over time.

Psychometric validation of a 7C-model of antecedents of vaccine acceptance among healthcare workers, parents and adolescents in France.

Support for vaccine decision-making requires a tailored approach taking into account psychological antecedents of vaccine acceptance. We aimed at validating an extended 7C-model of antecedents in three different target population groups (healthcare workers [n = 3870], parents [n = 2002] and adolescents [n = 7118]) and two vaccinations (COVID-19, HPV) in France. We performed a secondary analysis of questionnaires collecting sociodemographic characteristics, attitudes and knowledge on vaccination, and vaccine status and intention. We used standard psychometric techniques to validate a first and second order latent structure, and evaluated their association with vaccine intentionality in three levels (refusal, indecision, acceptance). In all populations, the 7C-model yielded a very good model fit (CFI and TLI > 0.90) and, in comparison with non-nested and nested 5C-models, significantly improved the model performance (Ω2, p < 0.05; Wald's test, p < 0.05). The resulting vaccine readiness score was strongly associated with vaccine intentionality (acceptance vs. indecision: ßHCW = 2.93, ßParents = 2.41, ßAdolescents = 1.34; refusal vs. indecision: ßHCW = - 1.68, ßParents = - 0.16, ßAdolescents = - 0.89.). The addition of confidence in the system and social conformism among antecedents of vaccine acceptance allowed a finer understanding of the continuum moving from refusal to indecision and acceptance. To work with these antecedents in interventional research, appropriate questionnaire items should be developed for various vaccines and target populations.

Can physicians and schools mitigate social inequalities in human papillomavirus vaccine awareness, uptake and vaccination intention among adolescents? A cross-sectional study, France, 2021 to 2022.

BackgroundIn France, human papillomavirus (HPV) vaccination coverage varies across socioeconomic levels.AimWe aimed at assessing HPV vaccine awareness, uptake and vaccination intention among adolescents in France.MethodsIn a cluster-randomised study, 13-15-year-old students in 61 French middle schools completed a web-based questionnaire. We used multivariable logistic regression to evaluate determinants of HPV vaccine awareness, self-reported uptake and vaccination intention among unvaccinated students and interaction terms to explore effects of visits to family physician and remembering school lessons on vaccination. The French deprivation index of school municipalities served as proxy for socioeconomic levels.ResultsAmong 6,992 participants, awareness was significantly associated with parental education (odds ratio (OR) = 0.82; 95% confidence interval (CI): 0.71-0.95), language spoken at home (OR = 0.59; 95% CI: 0.52-0.66) and deprivation level (OR = 0.57; 95% CI: 0.44-0.71), regardless of physician visit or school lessons. Vaccine uptake was associated with parental education without a recent physician visit (OR = 0.31; 95% CI: 0.16-0.59, vs OR = 0.64; 95% CI: 0.52-0.78 with a visit, interaction p = 0.045). Vaccination intention among unvaccinated was associated with deprivation level (moderate-low vs low) among students not remembering school lessons on vaccination (OR = 0.17; 95% CI: 0.05-0.62, vs OR = 0.93; 95% CI: 0.51-1.67 remembering school lessons, interaction p = 0.022). Parental education was associated with vaccination intention among students reporting a physician visit (OR = 0.41; 95% CI: 0.26-0.64 vs OR = 1.05; 95% CI: 0.50-2.20 without a visit, interaction p = 0.034).ConclusionOur results suggest that healthcare and school could promote vaccination and mitigate social inequalities in HPV vaccination coverage.

Determinants of incomplete vaccination in children at age two in France: results from the nationwide ELFE birth cohort.

Incomplete vaccination in the pediatric population is a growing public health issue in high-income countries, but its determinants are poorly understood. Their identification is necessary to design target actions that can improve vaccination uptake. Our aim was to assess the determinants of incomplete vaccination in two-year-old children in France. Among the 18,329 children included in the 2011 ELFE French nationwide population-based birth cohort, we selected those for whom vaccination status was available at age two years. Incomplete vaccination was defined as ≥ 1 missing dose of recommended vaccines. Potential determinants of incomplete vaccination were identified by using logistic regression, taking into account attrition and missing data. Of the 5,740 (31.3%) children analyzed, 46.5% (95% confidence interval [CI] 44.7-48.0) were incompletely vaccinated. Factors independently associated with incomplete vaccination were having older siblings (adjusted odds ratio 1.18, 95% CI [1.03-1.34] and 1.28 [1.06-1.54] for one and ≥ 2 siblings, respectively, vs. 0), residing in an isolated area (1.92 [1.36-2.75] vs. an urban area), parents not following health recommendations or using alternative medicines (1.81 [1.41-2.34] and 1.23 [1.04-1.46], respectively, vs. parents confident in institutions and following heath recommendations), not being visited by a maternal and child protection service nurse during the child's first two months (1.19 [1.03-1.38] vs. ≥ 1 visit), and being followed by a general practitioner (2.87 [2.52-3.26] vs. a pediatrician). CONCLUSIONS: Incomplete vaccination was highly prevalent in the studied pediatric population and was associated with several socio-demographic, parental, and healthcare service characteristics. These findings may help in designing targeted corrective actions. WHAT IS KNOWN: • Incomplete vaccination in the pediatric population is a growing public health issue in high-income countries. • The partial understanding of the determinants of incomplete vaccination precludes the design of effective targeted corrective actions. WHAT IS NEW: • High prevalence of incomplete vaccination at age two years in France. • Incomplete vaccination was independently associated with several socio-demographic, parental, and healthcare service characteristics.

Testing a simple and frugal model of health protective behaviour in epidemic times.

The COVID-19 epidemic highlighted the necessity to integrate dynamic human behaviour change into infectious disease transmission models. The adoption of health protective behaviour, such as handwashing or staying at home, depends on both epidemiological and personal variables. However, only a few models have been proposed in the recent literature to account for behavioural change in response to the health threat over time. This study aims to estimate the relevance of TELL ME, a simple and frugal agent-based model developed following the 2009 H1N1 outbreak to explain individual engagement in health protective behaviours in epidemic times and how communication can influence this. Basically, TELL ME includes a behavioural rule to simulate individual decisions to adopt health protective behaviours. To test this rule, we used behavioural data from a series of 12 cross-sectional surveys in France over a 6-month period (May to November 2020). Samples were representative of the French population (N = 24,003). We found the TELL ME behavioural rule to be associated with a moderate to high error rate in representing the adoption of behaviours, indicating that parameter values are not constant over time and that other key variables influence individual decisions. These results highlight the crucial need for longitudinal behavioural data to better calibrate epidemiological models accounting for public responses to infectious disease threats.

Perceptions of COVID-19 self-testing and recommendations for implementation and scale-up among Black/African Americans: implications for the COVID-19 STEP project.

BACKGROUND: COVID-19 self-testing (ST) is an innovative strategy with the potential to increase the access and uptake of testing and ultimately to limit the spread of the virus. To maximize the uptake and reach of this promising strategy and inform intervention development and scale up, research is needed to understand the acceptability of and willingness to use this tool. This is vital to ensure that Black/African Americans are reached by the Biden-Harris Administration's free national COVID-19 ST program. This study aimed to explore the acceptability and recommendations to promote and scale-up the uptake of COVID-19 ST among Black/African Americans. METHODS: We conducted a cross-sectional qualitative study using a semi-structured questionnaire to assess barriers and facilitators to the uptake of COVID-19 ST among a convenience sample of 28 self-identified Black/African Americans from schools, community centers, and faith-based institutions in Ohio and Maryland. Inductive content analysis was conducted to identify categories and subcategories related to acceptability and recommendations for implementing and scaling up COVID-19 ST in communities. RESULTS: Participants perceived COVID-19 self-testing as an acceptable tool that is beneficial to prevent transmission and address some of the barriers associated with health facility testing, such as transportation cost and human contact at the health facility. However, concerns were raised regarding the accurate use of the kits and costs. Recommendations for implementing and scaling up COVID-19 ST included engagement of community stakeholders to disseminate information about COVID-19 self-testing and creating culturally appropriate education tools to promote knowledge of and clear instructions about how to properly use COVID-19 ST kits. Based on these recommendations, the COVID-19 STEP (Self-Testing Education and Promotion) Project is being developed and will involve engaging community partners such as barbers, church leaders, and other community-based organizations to increase the uptake and use of free COVID-19 ST kits among Black/African Americans. CONCLUSION: Findings showed that most participants considered COVID-19 ST valuable for encouraging COVID-19 testing. However, cost and accuracy concerns may pose barriers. Future work should consider implementing interventions that leverage the benefits of COVID-19 ST and further assess the extent to which these identified facilitators and barriers may influence COVID-19 ST uptake.

Cognitive Factors Associated With Public Acceptance of COVID-19 Nonpharmaceutical Prevention Measures: Cross-sectional Study.

Background: During the COVID-19 crisis, protests against restrictions emerged and rule violations increased, provoking peaks in new positive cases, forcing authorities in France to impose fines to slow down the spread of the disease. Due to these challenges, subsequent implementations of preventive measures in response to COVID-19 recurrences or other pandemics could present difficulties for decision makers. A better understanding of the factors underlying the public acceptance of COVID-19 nonpharmaceutical preventive measures may therefore contribute greatly to the design of more effective public communication during future pandemics. Objective: The aim of this study was to evaluate the acceptance of COVID-19 nonpharmaceutical prevention measures in France. The specific objectives were (1) to examine the public's acceptance of COVID-19 nonpharmaceutical prevention measures and (2) to assess the association of the public's acceptance of these prevention measures and their perception of COVID-19. Methods: Data were collected from 2004 individuals through an online survey conducted 6-8 weeks after the first lockdown in France. For objective 1, participants were asked the extent to which they supported 8 COVID-19 nonpharmaceutical preventive measures using a 4-point Likert scale. For objective 2, COVID-19-related perceptions were assessed using a 5-point Likert scale from an adapted version of Witte's Extended Parallel Process Model. Sociodemographic and environmental variables were also collected. The public's acceptance factors were estimated using an unweighted least squares factorial analysis, and their associations with perceptions of COVID-19, expressed as rate ratios (RR) and 95% CIs, were estimated using generalized linear Poisson regression models. Statistical analyses were performed using the SPSS statistical package. Results: The acceptance rate reached 86.1% for individual protective measures, such as making masks mandatory in public open spaces, and 70.0% for collective restrictions, such as isolating the most vulnerable people (1604/2004, 80%) or forbidding public gatherings (n=1590, 79.3%). The least popular restrictions were closing all schools/universities and nonessential commerce such as bars and restaurants (n=1146, 57.2%). Acceptance of collective restrictions was positively associated with their perceived efficacy (RR 1.02, 95% CI 1.01-1.03), fear of COVID-19 (RR 1.04, 95% CI 1.03-1.05), and perceived severity of COVID-19 (RR 1.04, 95% CI 1.03-1.06), and negatively with age >60 years (RR 0.89, 95% CI 0.81-0.98). Acceptance of individual protective measures was associated with their perceived efficacy (RR 1.03, 95% CI 1.03-1.04), fear of COVID-19 (RR 1.02, 1.01-1.03), and perceived severity of COVID-19 (RR 1.03, 1.01-1.05). Conclusions: Acceptance rates of COVID-19 nonpharmaceutical measures were rather high, but varied according to their perceived social cost, and were more related to collective than personal protection. Nonpharmaceutical measures that minimize social costs while controlling the spread of the disease are more likely to be accepted during pandemics.

Perception of the SARS-CoV-2 pandemic by pregnant women during the first lockdown in France: worry, perceived vulnerability, adoption and maintenance of prevention measures according to the Covimater study.

Background: We aimed to describe pregnant women's worry about the SARS-CoV-2 pandemic, the associated reasons, their perceived vulnerability to this infection, and factors influencing continued poor/non-existent or decreased implementation of preventive measures over time. Method: A cross-sectional study was conducted in July 2020 using a web-questionnaire completed by 500 women who were pregnant during the first lockdown in France (March-May 2020). Questions focused on worry caused by the pandemic, perceived vulnerability to infection by SARS-CoV-2 and implementation of preventive measures during and after lockdown. A robust variance Poisson regression model was used to estimate adjusted prevalence ratios (aPR) for perceived vulnerability and continued poor/non-existent or decreased implementation of preventive measures. Results: Participants felt significantly more vulnerable to infection than women of childbearing age who were included in a parallel study on the French general population, but were significantly less worried about the pandemic. Obese participants and those who unsuccessfully sought exchanges with healthcare professionals about their infection risk felt significantly more vulnerable (aPR = 1.32 95%CI[1.05-1.64] and 1.88 [1.43-2.48], respectively). Participants with continued poor/non-existent or decreased implementation of preventive measures two months after the lockdown ended were more likely to have experienced violence during the lockdown (2.06, [1.32-3.22]), or to live in areas less affected by the pandemic (1.66 [1.05-2.62]). A good knowledge of viral transmission (0.54 [0.30-0.97]) and a high perceived vulnerability score (0.66 [0.44-0.99]) were associated with maintained/increased implementation of preventive measures. Conclusions: Our results can guide prevention and support policies for pregnant women during pandemics, current or future.

Perceptions of COVID-19 Self-Testing and Recommendations for Implementation and Scale up Among Black/African Americans: Implications for the COVID-19 STEP Project.

Background COVID-19 self-testing (ST) is an innovative strategy with the potential to increase the access and uptake of testing and ultimately to limit the spread of the virus. To maximize the uptake and reach of this promising strategy and inform intervention development and scale up, research is needed to understand the acceptability of and willingness to use this tool. This is vital to ensure that Black/African Americans are reached by the Biden-Harris Administration’s free national COVID-19 ST program. This study aimed to explore the acceptability and recommendations to promote and scale up the uptake of COVID-19 ST among Black/African Americans. Methods We conducted a cross-sectional qualitative study using a semi-structured survey to assess barriers and facilitators to the uptake of COVID-19 ST among a convenience sample of 28 self-identified Black/African Americans from schools, community centers, and faith-based institutions in Ohio and Maryland. Inductive content analysis was conducted to identify categories and subcategories related to acceptability and recommendations for implementing and scaling up COVID-19 ST in communities. Results Participants perceived COVID-19 self-testing as an acceptable tool that is beneficial to prevent transmission and address some of the barriers associated with health facility testing, such as transportation cost and human contact at the health facility. However, concerns were raised regarding the accurate use of the kits and costs. Recommendations for implementing and scaling up COVID-19 ST included engagement of community stakeholders to disseminate information about COVID-19 self-testing and creating culturally appropriate education tools to promote knowledge of and clear instructions about how to properly use COVID-19 ST kits. Based on these recommendations, the COVID-19 STEP (Self-Testing Education and Promotion) Project is being developed and will involve engaging community partners such as barbers, church leaders, and other community-based organizations to increase the uptake and use of free COVID-19 ST kits among Black/African Americans. Conclusion Findings showed that most participants considered COVID-19 ST valuable for encouraging COVID-19 testing. However, cost and accuracy concerns may pose barriers. Future work should consider implementing interventions that leverage the benefits of COVID-19 ST and further assess the extent to which these identified facilitators and barriers may influence COVID-19 ST uptake.

Effectiveness of a Multifaceted Informational-Based and Text Message Reminders on Pneumococcal and Influenza Vaccinations in Hospital Emergency Departments: A Cluster-Randomized Controlled Trial.

OBJECTIVES: We aimed to evaluate the effectiveness of a multifaceted procedure in improving pneumococcal and influenza vaccinations 6 months after an emergency department (ED) visit among patients aged 65 years and older. METHODS: We conducted a cluster-randomized, controlled, parallel-group, open-label implementation trial in 18 EDs in France and Monaco. Participants were recruited from November 2015 to September 2016. EDs were randomly assigned with a 1:1 ratio to provide either a multifaceted procedure that combined structured information about pneumococcal and influenza vaccines and three text message reminders sent to patients every two weeks (intervention arm) or nonstructured information only (control arm). The outcomes were self-reported pneumococcal vaccination and influenza vaccination rates within 6 months of enrollment. RESULTS: A total of 9 EDs were randomized to the intervention arm (n = 780 patients) and 9 to the control arm (n = 695 patients). The median age for all enrolled patients was 74 years (25-75th percentiles, 69 to 82): 50.1% were male, 34.9% had at least one underlying condition, and 30.7% were at risk for invasive pneumococcal infection. In the intention-to-treat analysis, the multifaceted intervention did not alter the pneumococcal vaccination rate (6.4% versus 4.6%, absolute difference: 1.8; 95% CI: [-0.9 to 4.4]; p = 0.19), whereas it improved the influenza vaccination rate (52.1% versus 40.0%, absolute difference: 12.1; 95% CI: [2.4 to 21.8]; p = 0.01). At 12 months, mortality did not differ between the intervention (9.7%) and control (11.2%) arms (p = 0.35). CONCLUSIONS: A multifaceted intervention based on text message reminders provides an opportunity to increase anti-influenza vaccination among elderly patients visiting the ED. Efforts are warranted to provide better information on pneumococcal diseases and the benefits of pneumococcal vaccines, especially in the elderly.

Human papillomavirus (HPV) vaccine coverage rates (VCRs) in France: A French claims data study.

BACKGROUND: The French Cancer Plan 2014-2019 had a target of 60% HPV vaccine coverage. The PAPILLON study investigated the annual age-specific vaccination initiation rates and cumulative partial and complete vaccination rates in France from 2017 to 2022. It also identified the factors associated with vaccination in different age groups and those associated with the type of completion of the vaccination scheme (partial vs full vaccination). METHODS: For this publication, all females recorded in the French National Claims database who initiated HPV vaccination between 1 July 2007 and 31 December 2018 and were aged between 11 and 19 years at initiation were included. Annual HPV vaccination initiation rates were estimated in 11- to 14-year-old (target population) and 15- to 19-year-old females (catch-up). Cumulative vaccine coverage rates (VCRs) were estimated among those who were 15, 16, 20 and 21 years old. Partial vaccination was defined by dispensing of at least one dose of HPV vaccine by the pharmacy, while full vaccination was defined by two or three doses dispensed by a pharmacy over an 18-month period, according to current French recommendations based on the age at vaccination initiation. RESULTS: Among the 465,629 females who initiated HPV vaccination in 2017 or 2018, the initiation rate increased from 7.7 to 11.1% in 11- to 14-year-old girls and from 4.5 to 6.5% in 15- to 19-year-old females. In 2017 and 2018, the cumulative VCRs for partial vaccination by age 15 were 28.2% and 32.8%, respectively, while by age 20, they were 41.6% and 38.8%. The cumulative VCRs for full vaccination were 15.6% and 18.6% by age 16, while they were 25.9 and 23.6% by age 20. HPV vaccination initiation and completion were strongly associated with the use of health services. CONCLUSION: Overall, the HPV VCR substantively increased between 2017 and 2018, which is positive evidence of the resumption of vaccination. Updates in 2022 should confirm these results.

Optimising HPV vaccination communication to adolescents: A discrete choice experiment.

BACKGROUND: Human Papillomavirus (HPV) vaccine coverage in France is below 30%, despite proven effectiveness against HPV infections and (pre-)cancerous cervical lesions. To optimise vaccine promotion among adolescents, we used a discrete choice experiment (DCE) to identify optimal statements regarding a vaccination programme, including vaccine characteristics. METHODS: Girls and boys enrolled in the last two years of five middle schools in three French regions (aged 13-15 years) participated in an in-class cross-sectional self-administered internet-based study. In ten hypothetical scenarios, participants decided for or against signing up for a school-based vaccination campaign against an unnamed disease. Scenarios included different levels of four attributes: the type of vaccine-preventable disease, communication on vaccine safety, potential for indirect protection, and information on vaccine uptake among peers. One scenario was repeated with an added mention of sexual transmission. RESULTS: The 1,458 participating adolescents (estimated response rate: 89.4%) theoretically accepted vaccination in 80.1% of scenarios. All attributes significantly impacted theoretical vaccine acceptance. Compared to a febrile respiratory disease, protection against cancer was motivating (odds ratio (OR) 1.29 [95%-CI 1.09-1.52]), but not against genital warts (OR 0.91 [0.78-1.06]). Compared to risk negation ("vaccine does not provoke serious side effects"), a reference to a positive benefit-risk balance despite a confirmed side effect was strongly dissuasive (OR 0.30 [0.24-0.36]), while reference to ongoing international pharmacovigilance without any scientifically confirmed effect was not significantly dissuasive (OR 0.86 [0.71-1.04]). The potential for indirect protection motivated acceptance among girls but not boys (potential for eliminating the disease compared to no indirect protection, OR 1.57 [1.25-1.96]). Compared to mentioning "insufficient coverage", reporting that ">80% of young people in other countries got vaccinated" motivated vaccine acceptance (OR 1.94 [1.61-2.35]). The notion of sexual transmission did not influence acceptance. CONCLUSION: HPV vaccine communication to adolescents can be tailored to optimise the impact of promotion efforts.

Self-Illusion and Medical Expertise in the Era of COVID-19.

The Dunning-Kruger premise assumes that unqualified people are unaware of their limited skills. We tested this hypothesis in the context of the coronavirus disease 2019 (COVID-19) pandemic. In this cross-sectional study, 2487 participants had to self-estimate their knowledge about COVID-19 in a questionnaire on the topic. Poor performers were more likely to use mass media and social networks as sources of information and had lower levels of education. The mean self-assessment (SD) was 6.88 (2.06) and was not linked to actual level of knowledge. This observation should prompt regulatory agencies and media to apply rules that limit dissemination of "infodemics" during global health crises.

Beliefs and Risk Perceptions About COVID-19: Evidence From Two Successive French Representative Surveys During Lockdown.

BACKGROUND: The outbreak of COVID-19 has been a major interrupting event, challenging how societies and individuals deal with risk. An essential determinant of the virus' spread is a series of individual decisions, such as wearing face masks in public space. Those decisions depend on trade-offs between costs (or benefits) and risks, and beliefs are key to explain these. METHODS: We elicit beliefs about the COVID-19 pandemic during lockdown in France by means of surveys asking French citizens about their belief of the infection fatality ratio (IFR) for COVID-19, own risk to catch the disease, risk as perceived by others, and expected prevalence rate. Those self-assessments were measured twice during lockdown: about 2 weeks after lockdown started and about 2 weeks before lockdown ended. We also measured the quality of these beliefs with respect to available evidence at the time of the surveys, allowing us to assess the calibration of beliefs based on risk-related socio-demographics. Finally, comparing own risk to expected prevalence rates in the two successive surveys provides a dynamic view of comparative optimism with respect to the disease. RESULTS: The risk perceptions are rather high in absolute terms and they increased between the two surveys. We found no evidence for an impact of personal experience with COVID-19 on beliefs and lower risk perceptions of the IFR when someone in the respondent's family has been diagnosed with a disease. Answers to survey 1 confirmed this pattern with a clear indication that respondents were optimistic about their chances to catch COVID-19. However, in survey 2, respondents revealed comparative pessimism. CONCLUSION: The results show that respondents overestimated the probabilities to catch or die from COVID-19, which is not unusual and does not necessarily reflect a strong deviation from rational behavior. While a rational model explains why the own risk to catch COVID-19 rose between the two surveys, it does not explain why the subjective assessment of the IFR remained stable. The comparative pessimism in survey 2 was likely due to a concomitant increase in the respondents' perceived chances to catch the disease and a decreased expected prevalence rate.

Quantifying preferences around vaccination against frequent, mild disease with risk for vulnerable persons: A discrete choice experiment among French hospital health care workers.

The individual determinants of vaccine acceptance among health workers (HCWs) have been described in the literature, but there is little evidence regarding the impact of vaccine characteristics and contextual factors (e.g., incentives, communication) on vaccination intentions. We developed a single profile discrete choice experiment (DCE) to assess the impact of seven attributes on stated vaccination intention against an unnamed disease, described as frequent with rapid clinical evolution and epidemic potential (similar to influenza or pertussis). Attributes evaluated vaccine characteristics (effectiveness, security profile), inter-individual aspects (epidemic risk, controversy, potential for indirect protection, vaccine coverage) and incentives (e.g., badge, hierarchical injunction). A total of 1214 French hospital-based HCWs, recruited through professional organizations, completed the online DCE questionnaire. The relative impact of each attribute was estimated using random effects logit models on the whole sample and among specific subgroups. Overall, 52% of included HCWs were vaccinated against influenza during 2017-18 and the average vaccination acceptance rate across all scenarios was 58%. Aside from the management stance, all attributes' levels had significant impact on vaccination decisions. Poor vaccine safety had the most detrimental impact on stated acceptance (OR 0.04 for the level controversy around vaccine safety). The most motivating factor was protection of family (OR 2.41) and contribution to disease control (OR 2.34). Other motivating factors included improved vaccine effectiveness (OR 2.22), high uptake among colleagues (OR 1.89) and epidemic risk declared by health authorities (OR 1.76). Social incentives (e.g., a badge I'm vaccinated) were dissuasive (OR 0.47). Compared to HCWs previously vaccinated against influenza, unvaccinated HCWs who were favorable to vaccination in general were most sensitive towards improved vaccine effectiveness. Our study suggests that vaccine safety considerations dominate vaccine decision-making among French HCWs, while adapted communication on indirect protection and social conformism can contribute to increase vaccination acceptance.

The Health Professional's View on the Inclusion of Age in the Recommendations for Pneumococcal Vaccination: Results of a Cross-Sectional Survey in France.

Elderly people are at high risk for pneumococcal infections. However, older age is not an eligibility factor for pneumococcal vaccination in France. Adults with certain co-morbidities or immunocompromised states are eligible for vaccination, which leaves adults aged ≥65 years without comorbidities at-risk for pneumococcal infections. The objective of the study was to evaluate the acceptability to healthcare professionals (HCPs) of extending pneumococcal vaccination to all individuals ≥65 years. Based on themes identified in semi-structured interviews with 24 HCPs, a representative sample of 500 general practitioners and pharmacists were surveyed about their knowledge, attitudes and beliefs with respect to pneumococcal vaccination for individuals ≥65 years. Current recommendations for pneumococcal vaccination are poorly understood by participants (mean score: 5.8/10). Respondents were generally supportive of inclusion of age in vaccination recommendations (7.5/10), with 58% being very supportive. For 72% of HCPs, this would contribute to improved vaccination coverage. The strategy could be facilitated by associating pneumococcal vaccination with the influenza vaccination campaign (8.3/10). Pharmacists were favourable to participating in pneumococcal vaccination (8.5/10). In conclusion, extension of pneumococcal vaccination to all people aged ≥65 years would be welcomed by HCPs, simplifying identification of patients to be vaccinated and potentially improving vaccination coverage.

Are People Optimistically Biased about the Risk of COVID-19 Infection? Lessons from the First Wave of the Pandemic in Europe.

Unrealistic optimism, the underestimation of one's risk of experiencing harm, has been investigated extensively to understand better and predict behavioural responses to health threats. Prior to the COVID-19 pandemic, a relative dearth of research existed in this domain regarding epidemics, which is surprising considering that this optimistic bias has been associated with a lack of engagement in protective behaviours critical in fighting twenty-first-century, emergent, infectious diseases. The current study addresses this gap in the literature by investigating whether people demonstrated optimism bias during the first wave of the COVID-19 pandemic in Europe, how this changed over time, and whether unrealistic optimism was negatively associated with protective measures. Taking advantage of a pre-existing international participative influenza surveillance network (n = 12,378), absolute and comparative unrealistic optimism were measured at three epidemic stages (pre-, early, peak), and across four countries-France, Italy, Switzerland and the United Kingdom. Despite differences in culture and health response, similar patterns were observed across all four countries. The prevalence of unrealistic optimism appears to be influenced by the particular epidemic context. Paradoxically, whereas absolute unrealistic optimism decreased over time, comparative unrealistic optimism increased, suggesting that whilst people became increasingly accurate in assessing their personal risk, they nonetheless overestimated that for others. Comparative unrealistic optimism was negatively associated with the adoption of protective behaviours, which is worrying, given that these preventive measures are critical in tackling the spread and health burden of COVID-19. It is hoped these findings will inspire further research into sociocognitive mechanisms involved in risk appraisal.

Attitudes about COVID-19 Lockdown among General Population, France, March 2020.

Because the effectiveness of a coronavirus disease lockdown in curbing coronavirus disease spread depends on public support, acquiring real-time information about the way populations reacted to the lockdown is crucial. In France, such public support remained fragile among low-income persons, probably because the lockdown exacerbated preexisting social inequalities and conflicts.

Determinants of Preventive Behaviors in Response to the COVID-19 Pandemic in France: Comparing the Sociocultural, Psychosocial, and Social Cognitive Explanations.

In absence of effective pharmaceutical treatments, the individual's compliance with a series of behavioral recommendations provided by the public health authorities play a critical role in the control and prevention of SARS-CoV2 infection. However, we still do not know much about the rate and determinants of adoption of the recommended health behaviors. This paper examines the compliance with the main behavioral recommendations, and compares sociocultural, psychosocial, and social cognitive explanations for its variation in the French population. Based on the current literature, these 3 categories of factors were identified as potential determinants of individual differences in the health preventive behaviors. The data used for these analyses are drawn from 2 cross-sectional studies (N = 2,000 in survey 1 and 2,003 in survey 2) conducted after the lockdown and before the peak of the COVID-19 epidemic in France. The participants were drawn from a larger internet consumer panel where recruitment was stratified to generate a socio-demographically representative sample of the French adult population. Overall, the results show a very high rate of compliance with the behavioral recommendations among the participants. A hierarchical regression analysis was then performed to assess the potential explanatory power of these approaches in complying with these recommendations by successively entering sociocultural factors, psychosocial factors, social cognitive factors in the model. Only the inclusion of the cognitive variables substantially increased the explained variance of the self-reported adoption of preventive behaviors (R 2 change = 23% in survey 1 and 2), providing better support for the social cognitive than the sociocultural and psychosocial explanations.