Published: March 10, 2025 | Updated: September 8, 2026
As of the morning of Sept. 3, Kentucky has reported 38 confirmed measles cases, including three individuals who have been hospitalized. Most of the reported cases have occurred in pediatric patients. As of Sept. 2, Indiana has reported eight confirmed measles cases.
All children are recommended to get two doses of the MMR vaccine, starting with the first dose at age 12 months and the second dose between ages 4 years and 6 years. The second dose can be administered 28 days after the first. This is a valid dose and provides earlier protection for children.
Measles vaccine cannot be given to infants younger than age 6 months. For infants ages 6 months to 11 months traveling internationally or to a place with active measles transmission, an early dose is recommended. This early dose — “dose zero” — is considered supplementary and does not count toward the routine two-dose series. Infants who receive a “dose zero” need two additional age-valid MMR doses after 12 months of age, separated by at least 28 days. MMR, not measles, mumps, rubella and varicella (MMRV), is used for infants younger than 12 months. Early MMR is not universally recommended for all infants in this age group at this time.
Before any international travel, infants ages 6 months through 11 months should receive one dose of MMR vaccine. Infants who get one dose of MMR vaccine before their first birthday should get two more doses according to the routinely recommended schedule (12 to 15 months and 4 to 6 years). People ages 12 months and older who will be traveling internationally or to a place where an outbreak is occurring should receive two doses of MMR, unless they have other presumptive evidence of immunity. The minimum interval between vaccines is 28 days.
Most people are immune to measles due to routine childhood immunization. Older adults would have been exposed before measles had been considered eliminated in the United States. The presumptive criteria for immunity to measles includes any of the following:
No. People who received one or two doses of measles according to the U.S. vaccination schedule or have presumptive evidence of immunity to MMR, according to above, are usually considered protected for life and usually do not need a booster dose.
For most adults born after 1957, one dose of measles vaccine is sufficient to be considered protected from measles. Certain adults may need two doses. Adults who are going to be in a setting that poses a high risk for measles transmission should make sure they have had two doses separated by at least 28 days. These adults include:
Adults who were vaccinated between 1963 and 1967 with an older, less-effective measles vaccine need to be revaccinated with at least one MMR dose to ensure they are protected.
Individuals can check vaccination records for themselves or their children using the Kentucky Immunization Registry Public Portal or MyVaxIndiana, though these records may be incomplete for adults unless their healthcare provider back-entered their historical vaccine doses.
If patients born after 1957 do not have written documentation of measles immunity, recommend testing to determine immunity or vaccinate with another dose of MMR.
Norton Healthcare/Norton Children’s employees who are unsure about their immunity to measles can contact Employee Health.