Rapid Vaccination of Hard-To-Reach Populations

Primary Outcome Measures:

• Compare vaccination rates in selected neighborhoods before and after a multilevel community-based participatory intervention trial.
  

Secondary Outcome Measures:

• Determine and identify the relative contributions of personal factors and structural barriers to immunization status in hard-to-reach populations.
  
• Estimate the size of the hard-to-reach populations.
  

This study follows a quasi-experimental design involving a multilevel community participatory intervention that is designed to rapidly immunize hard-to-reach (HTR) populations in disadvantaged minority communities. Low vaccination coverage among minorities and persons living in and near poverty is a persistent problem that is particularly acute among HTR populations (e.g. injection drug users, elderly shut-ins). Immunization rates are affected by multiple factors including demographics, attitudes about vaccination, health norms, barriers to access, and immunization delivery methods. Efforts to successfully vaccinate HTR populations must address these factors. A community-based program with rapid vaccination can serve as an initial model for emergency preparedness vaccination plans and for future efforts to widely introduce HIV vaccination in disadvantaged urban communities. This project will be conducted by a community-public health partnership in eight disadvantaged neighborhoods within Harlem and the South Bronx in three phases. In Phase 1 we will implement a brief survey assessment of residents in designated neighborhoods to identify current key barriers to immunization faced by the target HTR populations in these neighborhoods. Also, using several estimation methods, we will determine the size of the target populations in the study neighborhoods to establish vaccine needed and to estimate denominators for vaccination rates. In Phase 2, we will implement two waves of a multilevel community intervention trial (developed with input from the survey and community partners). In the first wave, four randomly selected neighborhoods will receive the intervention (i.e., community education, community-organization engagement, and door-to-door influenza vaccination program for eligible groups etc). In the four control communities, target populations will be invited to come for vaccination at specified locations as part of usual public health efforts. In the second vaccination wave, using a crossover design, after updating and revising the approach based on experience from Wave 1, we will implement the intervention in the four control communities; this vaccination wave will be conducted over one week to test the feasibility of rapid vaccination of these populations. Phase 3 of this project will identify the promising elements of the program and develop materials to allow generalizability to other urban areas and to other vaccines (e.g., HIV, HBV, etc).