Impact of community pharmacists and pharmacies on immunization services in the U.S

Named as one of the ten greatest public health achievements by CDC, immunization has prevented many diseases and saved billions of dollars. Despite its effectiveness, immunization rates for many diseases remain below the Healthy People 2020 objective. Access and awareness are two major barriers, which community pharmacists and pharmacies are well positioned to address because of their convenient locations, flexible hours, and deep connections with local residents. However, there are very limited studies to quantify their impacts on immunization services at the national level.

This is the first study using nationally representative databases to quantify their impacts after adjusting both individual- and community-level characteristics. We merged the 2008-2012 Behavioral Risk Factor Surveillance System (BRFSS), the 2012-2013 Area Health Resources Files (AHRF), the 2010 County Business Patterns (CBP) from Census, and the location and service information of CVS and Walgreens from their websites to examine the effect of neighbourhood characteristics, particularly the supply of pharmacists and pharmacies, on individual immunization outcomes after controlling individual and family-level demographic, socioeconomic, health information, as well as county-level racial compositions and income levels.

We used probit models and marginal effects after estimation to analyze six immunization services for the entire sample as well as sub-samples across racial/ethnic groups, urban/suburban areas, and employment status. The immunizations included (1) seasonal flu for adults aged 18 and above, (2) seasonal flu for children less than 18 years old, (3) human papilloma virus (HPV) for female adults, (4) human papilloma virus (HPV) for female children, (5) pneumococcal vaccinations for adults aged 18 and above, and (6) shingles vaccination for adults aged 60 years and older. With a few exceptions, the density of community pharmacists and pharmacies are positively and significantly associated with these services. For example, an increase of one pharmacist per 10,000 population in a county is associated with 0.41%, 0.27%, 0.08% and 0.9% increase in the probability of adult flu vaccination for the entire sample, non-Hispanic white subsample, non-Hispanic black subsample, and the Hispanic subsample. The association is also positive and significant for the subsamples by urban/suburban types, and employment status.

With the introduction of free immunization services under the 2010 Patient Protection and Affordable Care Act, this study has important public health implications on using community pharmacists and pharmacies as non-traditional settings to expand access to vaccines.