Integrating Vaccination Into Hospital Care Pathways for Vulnerable Patients

Vaccination coverage among hospitalized and chronically ill patients remains suboptimal despite strong national and international recommendations. Hospital settings represent a strategic opportunity to identify vulnerable patients, reduce missed vaccination opportunities, and improve access to preventive services.

AMBU-VAX is a prospective observational study conducted at Fondazione Policlinico Universitario "A. Gemelli" IRCCS, Rome. The study targets adult patients affected by chronic diseases or immunocompromising conditions eligible for recommended vaccinations according to the Italian National Immunization Plan 2023-2025.

Patients are identified during outpatient visits, hospital admissions, or at discharge. Vaccination is actively proposed and, when accepted, administered within the hospital vaccination clinic or ward. When appropriate, patients are referred to local vaccination services to complete their immunization schedule.

Primary outcomes include vaccination offer, vaccine uptake, number of administered doses, and completion of vaccination pathways within the hospital setting. Secondary outcomes include reasons for vaccine refusal and referral to territorial vaccination services.

The study aims to assess the feasibility, effectiveness, and sustainability of a hospital-based vaccination model that can be replicated in other healthcare settings.

• Hospital-Based Vaccination Pathway (Biological): Integration of vaccination counseling, prescription, and administration into hospital care pathways for vulnerable adult patients, including coordination with local public health vaccination services. No experimental vaccine is used; all vaccines are administered according to national guidelines.

Primary outcomes

• Vaccination Offer Rate [12 months]: Proportion of patients evaluated by the vaccination service who are offered at least one recommended vaccination.
• Vaccination Uptake Rate [12 months]: Proportion of patients who receive at least one vaccination among those evaluated.
• Number of Administered Vaccine Doses [12 months]: Number of doses administered by vaccine type
• Completion of Hospital-Based Vaccination Pathway [12 months]: Proportion of patients completing all scheduled vaccine doses within the hospital setting.

Secondary outcomes

• Reasons for Vaccine Refusal [12 months]: Distribution of reported reasons for refusal among patients offered vaccination.
• Referral to Territorial Vaccination Services [12 months]: Proportion of patients referred to local public health vaccination services.
• Specialist Evaluation for Contraindications [12 months]: Proportion of patients with contraindications who complete specialist evaluation and receive clearance for vaccination.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Adults aged ≥18 years
* Presence of at least one chronic or immunocompromising condition eligible for vaccination according to national guidelines
* Written informed consent provided

Exclusion Criteria:

* Age <18 years
* Conditions not included among the predefined eligibility criteria

• Patrizia Laurenti, Professor, Principal investigator, Fondazione Policlinico Universitario Agostino Gemelli IRCCS