The Most—And Least—Vaccinated States, Mapped

Vaccines have been getting more attention with recent measles outbreaks and debates about the safety of vaccines.

An important part of vaccine effectiveness in preventing disease spread is herd immunity, which means enough people in an area have protection against a disease to make it less likely to spread. In fact, the World Health Organization declared smallpox eradicated in part due to vaccines that protected large groups of people from the disease. But diseases that are prevented by vaccines can also spread again with lower vaccination rates, and a rise in measles cases in recent years can be partially attributed to a decline in vaccination rates.

So which states have strong vaccination rates, and where could low vaccination rates be an issue? WalletHub reviewed 16 key data points to find the states where vaccine rates are doing well, and the states where vaccine uptake could be a concern.

Vermont Leads States That Vaccinate the Most

Vermont came in first place in WalletHub's survey, earning the spot due to high scores across several key metrics. The state has an 87% vaccination rate for the seven-vaccine series for children three years old and under. That's the highest level of any state. It also has the highest flu vaccine rate for children and the highest flu vaccine rate for adults.

Massachusetts came in second place, particularly due to its first-place rank among all states for its immunization rate among children and teenagers. One reason for this higher uptake rate may be because it's one of only 18 states that allow minors to receive vaccines without parental consent. The state also has the lowest share of civilian population without health insurance.

New Hampshire came in third place, lifted by the second-highest vaccination rate in the country for adults and the elderly. Rhode Island came in fourth with the fourth-highest rate for immunizations among children and teens, helped by the fact that it has the third-highest flu vaccination rate for children and teens. But Rhode Island sank due to an 18th-place ranking for adult and elderly vaccination uptake.

Based on data from WalletHub, the top 10 most vaccinated states are:

1. Vermont
2. Massachusetts
3. New Hampshire
4. Rhode Island
5. Maine
6. Pennsylvania
7. Wisconsin
8. Virginia
9. Minnesota
10. Washington

Mississippi Leads Least Vaccinated States

Southern states don't fare as well when it comes to vaccine rates, with the top three least vaccinated states in the South.

Mississippi tops the list of least-vaccinated states, driven by the lowest rate in the country for immunization of children and teenagers as well as adults and the elderly. It specifically ranks the lowest among all states for flu vaccination rate among children and teens while also having the second-lowest vaccination rate for the flu among adults. Mississippi adults also had the lowest rate for the tetanus vaccination and the Zoster vaccination, which is used to protect against shingles.

Second-place Oklahoma had its score hurt by the second-lowest rate for vaccines among children and teens in the state. Third-place Alabama has the second-lowest rank for vaccines among adults and the elderly. And Alaska, which came in fourth place, had the lowest ranking for immunization uptake disparities, which includes immunization uptake in children, the share of the population without health insurance, and the share of the population participating in an immunization information system.

The 10 states that vaccinated the least include:

1. Mississippi
2. Oklahoma
3. Alabama
4. Alaska
5. Wyoming
6. Texas
7. Nevada
8. Kentucky
9. Tennessee
10. Idaho

More State-By-State Data: