COVID-19 Vaccination Linked to Greater Rates of Primary Care Physicians

Andrew T. Chan, MD, MPH

The presence of primary care physicians throughout a US community is associated with a greater rate of COVID-19 vaccination rates among its people, according to findings from a new research letter.

New data from a team of US investigators show a positive correlation between primary care physician and COVID-19 vaccination prevalence throughout the country. The cross-sectional study, which took into account data from 87.2% of all US counties, highlights the suggested benefit of frontline physicians in improving vaccine acceptance among people—especially in regions with lesser healthcare literacy and resources.

Led by Andrew T. Chan, MD, MPH, of the Clinical and Translational Epidemiology Unit at Massachusetts General Hospital and Harvard Medical School, the team sought to interpret the association of numbers of primary care physicians per capita with COVID-19 vaccination rates among US counties.

As they noted, more participation from frontline physicians in vaccine distribution is a suggested resolve to vaccine hesitancy—one of the greatest hurdles in improved national vaccination against the pandemic virus.

“Survey data suggest that a substantial portion of the unvaccinated population would be willing to get vaccinated if they had greater access to accurate information and receive encouragement from a trusted source,” they wrote. “Primary care physicians can reach such individuals through direct engagement or alliances with community health workers, community centers, and mass-vaccination sites.”

Chan and colleagues conducted a cross-sectional analysis of the available data from 2739 of the 3142 total US counties. Among the excluded regions with insufficient vaccination data and missing variables were 8 California counties with populations of <20,000 people, as well as 6 states: Alaska; Georgia; Hawaii; Vermont; Virginia; West Virginia.

Primary care physicians—which included general family medicine, general practice, general internal medicine and general pediatrics physicians—per 100,000 population were defined for each observed county. Centers for Disease Control & Prevention (CDC) and 3 state health departments (Colorado, Massachusetts, Texas) provided data for percentage of populations fully vaccinated against SARS-CoV-2.

The team then examined associations between primary care physicians per 100,000 and COVID-19 vaccination rates via estimating equal models with multivariables adjusting for demographic factors, urbanity, socioeconomic status, and political leaning.

Among the observed counties, primary care physicians were most concentrated in Northeast, Florida, and various counties throughout the Midwest and West. Roughly, investigators noted, this finding corresponded to the distribution of counties with greater rates of COVID-19 vaccination.

Counties in the highest decile of primary care physicians per 100,000 were associated with a 5.5% greater vaccination rate versus those in the lowest decile (95% CI, 2.6 - 8.4), after adjusting for potential confounders.

As such, investigators confirmed that every 10 additional primary care physicians per 100,000 population was associated with a 0.3% increased COVID-19 vaccination rate (95% CI, 0.2 - 0.4). Further analyses showed similar positive associations between primary care physicians per capita and vaccination rates in rural areas or those with <2500 urban population (0.5%; 95% CI, 0.3 - 0.7), as well as in the 10 states with the greatest share of Republican Party votes in the most recent election (0.4%; 95% CI, 0.2 - 0.6).

Chan and colleagues concluded the findings suggest primary care physicians play a “critical role” in ensuring COVID-19 vaccine acceptance—possibly through means of patient counseling and bolstering local community trust prior to the vaccines becoming available.

“This study’s results provide support for expanding COVID-19 vaccine distribution to primary care physicians,” investigators wrote. “Although fully incorporating primary care physicians into vaccination campaigns poses many challenges,(they) may leverage their role as trusted messengers of scientific knowledge and educate communities about the importance of vaccination.”

The study, “Association of Primary Care Physicians Per Capita With COVID-19 Vaccination Rates Among US Counties,” was published online in JAMA Network Open.