General Population and Healthcare Professionals' Level of Knowledge of the Burden and Prevention of Respiratory Syncytial Virus in France

Respiratory viral infections are both common and potentially severe. Their incidence and microbial diversity have risen, with notable changes in the last decade primarily driven by greater awareness and testing capabilities [1-4]. Pneumonia resulting from these pathogens is more common and severe in the elderly and those with comorbidities, particularly in immunocompromised individuals [5]. Due to the development of new treatments for cancer and autoimmune diseases, the number of patients at high risk of severe infections has increased significantly [6, 7]. This trend highlights the need for global and targeted public health prevention measures, including developing new vaccines and enhancing existing ones. However, even among those most at risk [8], inadequate vaccination coverage is currently a critical issue.

Respiratory syncytial virus (RSV) is an excellent example of a pathogen that is (i) becoming increasingly known of being burdensome on the healthcare system with its high morbidity rate in elderly, immunocompromised patients and those with chronic conditions, (ii) having new preventive tools available. Three vaccines, one monovalent adjuvanted protein vaccine (RSVpre-F3), one bivalent nonadjuvanted protein vaccine (RSVpre-F), and one monovalent mRNA vaccine (mRNA-1345) have been granted marketing authorization by the Food and Drug Administration and European Medical Agency in adults aged 60 years and over in 2023 and 2024. Furthermore, the RSVpre-F has been approved in pregnant women to protect newborns. These vaccines are recommended for people of different ages and with various risk factors worldwide. In July 2024, the French NITAG (National Immunization Technical Advisory Group) recommended RSV vaccination for those over 75 years, those over 65 with a chronic cardiac or respiratory condition, and pregnant women. Additionally, nirsevimab, a long-acting monoclonal antibody for RSV, has been available and recommended in France for infants in their first year of life since winter 2023/2024, with the option of maternal immunization left to the parents. Both nirsevimab and maternal RSVpre-F have received reimbursement approval. RSV vaccines for older adults are still pending reimbursement.

More than ever, we must provide clear and appropriate information to these populations regarding viral respiratory infections and ways to prevent them.

This study aimed to provide an overview of the knowledge of a broad sample of French individuals from the general population and their caregivers concerning RSV infection and prevention.

Our study had the advantage of surveying a large representative sample of French people, isolating an at-risk population, and examining the knowledge of HCPs.

On the eve of the large-scale commercialization of vaccines against RSV, the issue of vaccine acceptance is more relevant than ever.

Our findings among the French population are the same as in other Western countries: Public knowledge of the epidemiology and potential seriousness of viral respiratory infections is mainly inadequate, given their frequency and impact on public health and the healthcare system [11]. This is especially true for the RSV. Indeed, we found that 94% of the general population participants claimed more information about RSV, and 68% of those most at risk of severe forms were unaware of its potential lethality, highlighting the crucial need for education and awareness campaigns.

A similar survey was conducted in the United States in May and June 2022 among people aged over 60 or under 60 year but with diabetes or chronic pulmonary or cardiovascular disease [12]. More than 55% had never heard of RSV, especially in the older age groups, and 19% did not know that it can cause severe forms of the disease.

In China in 2023, Wang et al. [13] sent a questionnaire to 2133 participants representing the general population to assess their knowledge of RSV. The results showed that 24.3% of respondents had never heard of this, but the majority were interested in learning more, and 68.4% were willing to be vaccinated against the virus. Factors that positively correlated with vaccine acceptance were age, level of education and standard of living, medical history, and knowledge of RSV.

The need for more education at all system levels explains why healthcare providers feel powerless to educate their patients about appropriate health behaviors properly. Our study reminds us of the vital role that physicians and paramedics play in health education despite their lack of knowledge on the subject, knowing that most of those surveyed expressed a willingness to receive the RSV vaccine if it reduces transmission and the risk of severe forms.

RSV vaccine hesitancy, as for all vaccines, might be an issue shortly. The 3C model of vaccine hesitancy considers complacency, confidence, and convenience as contributing factors. Complacency occurs when perceived risks of vaccine-preventable diseases are low, and vaccination is not deemed a necessary preventive action. For RSV, historical literature and recent media reports mainly focus on its incidence among children and the resulting burden on primary care and hospital services. It is thus unsurprising that both clinicians and the public view RSV as exclusively a childhood concern.

Confidence, a key component of the 3C model, is built on trust in the effectiveness and safety of vaccines. This trust is fostered by the rigorous testing and monitoring processes that vaccines undergo before they are approved for use which has been the case for the three authorized RSV vaccines. The duration of time on the market may also affect confidence, as it enables the collection of real-world data confirming efficacy and safety.

Convenience, the third component of the 3C model of vaccine hesitancy, plays a significant role in vaccine uptake. Factors such as physical availability, affordability, geographical accessibility, and the appeal of immunization services can all positively influence vaccination rates. For RSV, the vaccine's duration of protection across at least two seasons and the option of coadministration are expected to further enhance the convenience of being vaccinated.

It is essential that public health campaigns are designed to target not only the general population but also HCPs. This targeted approach can help bridge the gap in healthcare education and reduce vaccination hesitancy. It is crucial to understand the rationale behind health behaviors to fully appreciate their benefits. This understanding is often lacking, leading to inadequate education and a reluctance to vaccinate. The public often fills these gaps in understanding through less reliable sources, such as the Internet and social networks, which can negatively impact vaccine opinion [14-17].

Therefore, Berrada et al. defined three main themes in their qualitative study concerning vaccination hesitancy: restoration of trust in vaccine policy, improvement of the initial and further training of healthcare workers, and better communication with the population [18].

Our study has several limitations that we must acknowledge. First, the design of the study may have introduced social desirability bias, leading to an overestimation of the frequency of information and positive attitudes towards vaccination among HCPs and the general population. Second, the study was conducted during the COVID-19 pandemic, which could have influenced respondents' knowledge about respiratory infections and their opinions on vaccination. Lastly, our sample from the general population included only 40% of at-risk patients, whose responses are particularly significant as they are the primary targets of vaccine recommendations.

In conclusion, we found that French people and their caregivers have limited knowledge about respiratory viruses including RSV and often underestimate its dangerousness, even those who are at risk of developing severe forms. Given the prevalence and morbidity of these diseases large-scale awareness campaigns must be conducted primarily among HCPs, who remain one of the most important sources of health information for the public. These issues are more relevant than ever on the eve of the large-scale use of vaccines against RSV.

Ipsos was funded by Janssen.

Janssen had no role in data analysis, decision to publish or preparation of the manuscript.

Joshua Puel: writing – original draft. Katia Sosnowiez: methodology, conceptualization. Robin Stephan: writing – review and editing. Albert Sotto: writing – review and editing. Paul Loubet: conceptualization, supervision, writing – original draft, writing – review and editing, validation, methodology.

P.L. has received payment or honoraria for lectures, presentations, speakers bureau, manuscript writing, or educational events from AstraZeneca, GlaxoSmithKline, Janssen, Moderna, Merck Sharp & Dohme, Pfizer, Sanofi Pasteur, and Seqirus. K.S. is an employee of Janssen and may hold shares or stock options in the company.

The other authors have no competing interest.