Determinants of influenza vaccination among undocumented immigrant populations in underserved areas of New York City

Among residents of underserved urban areas, low influenza vaccination rates are a major public health concern. For undocumented immigrants in these areas, access to disease prevention methods such as vaccination is particularly challenging. Interventions that can improve vaccination rates among undocumented immigrants may reduce population morbidity and mortality secondary to influenza. We examined determinants of prior influenza vaccination among undocumented immigrants recruited through Project VIVA, a community-based intervention in East Harlem and the Bronx neighborhoods of New York City that was designed to offer influenza vaccine in non-traditional (door-to-door and street-based) settings. Of 7,480 survey participants, 16% (1,172) were classified as a possible undocumented immigrant (non-Puerto Rican Hispanic/Latino, and received no government health or social services). Among undocumented immigrants, mean age was 37 years, 50% were female, 46% reported Mexican origins, 31% reported Dominican origins and 53% reported an annual income of $4,800 or less. 36% had received a prior influenza vaccination, compared to 69% of those surveyed overall (p<0.0001). In fully adjusted models, characteristics significantly associated with prior flu vaccination were older age, being covered by non-federal health insurance, accessing routine medical care, current drug use, prior hepatitis vaccination, prior HIV test, and being medically-indicated to receive flu vaccine. Amongst those with no prior vaccination, 90% were interested in being vaccinated. These findings suggest that although vaccination coverage is low among undocumented immigrants, interest in receiving vaccination is high. Persons who cannot access routine medical care can benefit from tailored interventions designed to increase vaccination coverage.