The goal of this initiative is to collectively identify appropriate approaches and courses of action. Today, Santé publique France is publishing the key findings of this initiative regarding vaccination. The findings indicate that, following a detailed contextual analysis of the drivers and barriers to vaccination, the strategies to be implemented must promote a vaccination pathway capable of “bringing people back” to vaccination sites and “reaching out” to their communities, while taking their expectations into account. They must therefore build on pre-existing relationships of trust between frontline workers and the populations, and promote regular training and ongoing information sharing for frontline workers. In direct connection with this work, two initiatives have been implemented: support for the Prevac study to estimate Covid-19 vaccination coverage among this population, which will complement the national estimates from the VAC-SI program for the general population; and the creation of a set of tailored educational resources, updated monthly, intended for frontline workers serving people in precarious situations.

A major challenge: people in precarious situations are less vaccinated than the general population

Homeless people are generally less vaccinated than the general population. For these people in precarious situations, the barriers to vaccination are numerous and can vary by population. Among them are difficulty accessing healthcare services, past negative experiences for people experiencing homelessness; fear of side effects that would exacerbate the hardships of life on the streets, language barriers, lack of tailored information, and fear of being identified and deported.

A collaborative approach to developing tailored and effective vaccination strategies

Since fall 2020, to improve COVID-19 prevention among vulnerable populations, Santé publique France has implemented the Knowledge Mobilization (MobCo) initiative. Initially focused on testing strategies, it has evolved to address vaccination strategies. It involves bringing together the theoretical knowledge of researchers and the experiential knowledge of decision-makers and field workers, and sharing it to develop new integrated knowledge during the health crisis. As part of the expansion of the COVID-19 vaccination strategy, an initial phase identified effective strategies to facilitate vaccination uptake among vulnerable populations in general. Of the 531 articles and reports identified in the international literature, 17 articles were selected. Subsequently, an international benchmark study was conducted to gather feedback from stakeholders in three countries (Denmark, Israel, and Ireland) that had implemented a national vaccination program for highly vulnerable populations as early as February 2021. Finally, individual interviews with field practitioners—from public administration, associations, and sector-specific groups of healthcare and social sector professionals—in France allowed for the consideration of their experiences and the identification of their needs following the implementation of Phase 4 of the vaccination schedule.

This preliminary work formed the scientific basis for discussions (webinars and participatory workshops) centered on four key issues: vaccination intent and uptake; population-specific characteristics; information, education, and communication strategies; and support mechanisms and initiatives.

Lessons learned and initial actions developed collectively

The initial work identified several key points:

• The importance of capitalizing on pre-existing relationships of trust with vulnerable populations. And of structuring the health system (clear definition and allocation of roles for each actor involved in implementing the vaccination strategy) to facilitate the involvement of local actors and associations.

• The need to incorporate sustained, long-term information, education, and communication efforts targeting these populations, carried out as close as possible to where they live and led by local actors trained in these issues.

• The need to integrate vaccination efforts into routine healthcare and services, as part of an approach to “bring services to” the population and “reach out to” their communities.

• Taking into account limiting factors such as: intense competition among basic needs—housing, security, work, access to water, food; child care; potential substance use; high mobility; low levels of health literacy and digital literacy; language barriers; distance from institutional systems; and a low perception of the value of vaccination or the threat of COVID-19. All these contextual factors are significant within these populations and require detailed and specific analysis, in real-time and on-site.

From Approach to Action

Furthermore, two initiatives have emerged from this work:

• The implementation by Santé publique France of a system of tailored, educational resources in the form of Q&As to meet the knowledge needs of professionals (social workers, health mediators, healthcare professionals) or volunteers working on the front lines with vulnerable populations, and adapted to on-the-ground realities. This co-developed resource is updated monthly based on feedback from field workers, incorporating and reflecting new knowledge. It aims to facilitate discussions about COVID-19 vaccination with vulnerable populations: people experiencing homelessness, migrants, Travellers, sex workers, etc. Subscribe here.

• The Prevac study, coordinated by Epicentre in partnership with Santé publique France, aims to assess COVID-19 vaccination coverage among highly vulnerable individuals who fall outside standard surveillance systems, in collaboration with several partners (Médecins sans frontières, Médecins du monde, Samu social, Interlogement 93, the French Red Cross, and the regional health agencies of Île-de-France and Provence-Alpes-Côte d’Azur). The results of this study will be published shortly.