Understanding longstanding barriers to vaccine uptake is necessary to ensure the success of Covid-19 vaccination efforts. This analysis examines historic vaccination patterns among adults using data from the 2016-18 National Health Interview Survey (NHIS). We examine flu vaccination rates among three risk groups: nonelderly adults (ages 19-64) at low- and high-risk of severe disease from Covid-19, and all elderly adults ages 65 and over. We also consider pneumonia and shingles vaccination rates among the elderly. For each risk group and vaccine, we examine variation in vaccination rates by gender, race, ethnicity, region, income relative to poverty, insurance coverage and presence of a usual source of care. We find that lower income adults were less likely to be vaccinated than those with higher incomes, and adults in the southern US had the lowest vaccination rates compared to other regions. Black and Hispanic adults were less likely to receive a flu vaccine than their white counterparts, and these patterns persisted across most risk and income groups. Among the nonelderly Black, Hispanic, Medicaid/CHIP and lower income adult populations, the higher risk group was more likely to receive their flu vaccine than their lower risk counterparts. Flu vaccination rates among uninsured adults and those lacking a usual source of care were among the lowest observed, at rates below 20 percent among both the high and low risk nonelderly. These findings emphasize the need for explicit consideration of racial and socioeconomic equity in prioritizing rollout of the Covid-19 vaccine. This will require a robust and varied network of vaccine providers serving adults with low incomes, no insurance, and people of color, assistance with the logistics of scheduling appointments, and targeted messages to address vaccine hesitancy.