ESCANABA — As confirmed measles cases continue to rise in the southern U.S., Canada, and Lower Michigan, the percentage of local residents immunized against the virus remains below the recommended number.

However, a much higher percentage of people have received at least the two-dose measles, mumps and rubella (MMR) vaccine than the entire series of recommended vaccines, perhaps indicating that people trust it more than other vaccines or consider it more necessary.

In Delta County, 86.2% of 19- to 36-month-olds have received the first dose of the MMR vaccine, and 89.9% of 13- to 18-year-olds have received both doses, according to Public Health for Delta and Menominee Counties (PHDM). Within those same age groups, only 57% of infants and 42% of teens in Delta County have received all vaccines recommended for their age groups.

In Menominee County, 76.4% of 19- to 36-month-olds have received one MMR dose, and 82.4% of 13- to 18-year-olds have had two.

Because of measles’ high ­transmission rate — 90% of people exposed catch it, making it “one of the world’s most contagious diseases,” according to the World Health Organization (WHO) — experts recommend that at least 95% of the population be vaccinated to maintain herd immunity.

“Herd immunity occurs when enough people are immune to a virus, which helps to significantly limit its spread,” said Jennie Miller, RN, BSN and immunization coordinator with PHDM. “Think of each potentially infectious person as a stepping-stone for the virus. The more immunized people there are, the fewer stepping-stones, and the virus is unable to spread further. The percentage of individuals required for herd immunity varies by virus and depends on how contagious it is.”

With well below 95% of the public immunized, and with measles spreading in other locations, an outbreak in the Upper Peninsula can’t be ruled out.

An “outbreak” is defined as three or more confirmed related cases. An outbreak currently downstate in Montcalm County has been tied to an outbreak in Ontario, where 925 cases have been confirmed between October and April. Other confirmed cases in Michigan this year were reported in Oakland, Kent, Macomb and Ingham Counties. Michigan has seen a total of nine confirmed cases this year, as of April 24.

Meanwhile, the illness is spreading rapidly in the southern states. The Texas Department of State Health Services confirmed 624 cases in three months (between Jan. 23 and April 22).

In 1980, a measles epidemic spread through Rapid River, with 32 cases confirmed and seven suspected in a five-week span after a soldier on leave brought the virus home, the Daily Press reported at the time. That outbreak accounted for over half Michigans’s cases in the time period, a state public health department official said.

The last cases of measles recorded by PHDM were in Menominee County in 1989.

Measles was declared eliminated from the U.S. in 2000, meaning there were no ongoing transmissions for over 12 months. Over the next 20 years, occasional outbreaks occurred, usually associated with international travel, but deaths were rare — one every few years. In 2025, already three people with confirmed measles cases have died: two unvaccinated children in Texas, and one unvaccinated adult in New Mexico who did not seek medical treatment and was found to be infected after death.

Measles, which can be contracted by contact or through the air, is characterized by first a fever, cough, runny nose, and pinkeye; then, white spots in the mouth; and three to five days after symptoms begin, a splotchy rash. Symptoms do not present until a week or two after exposure, and a person is contagious about four days before they have any symptoms.

According to the WHO, complications can include blindness, encephalitis (brain swelling, which can result in permanent brain damage or death), ear infections, and severe breathing problems.

The CDC reports that one out of five unvaccinated people end up hospitalized when they catch measles, that one to three out of 1,000 children infected die, and one out of 20 children with measles gets pneumonia — the most common cause of death from measles in young children.

Considered highly effective, the two-dose MMR vaccine has been administered since 1971, when inoculations for measles, mumps and rubella were combined. Though the first measles vaccine, an inactivated (killed) version, was made available in 1963, it was considered not as effective as the version released in 1967, which contained attenuated (weakened) virus.

People born before 1957 are generally considered immune to measles. Because of the high transmissibility of measles, prior to the vaccine, most people had contracted it and therefore carry antibodies.

The MMR shot is suitable for the vast majority of people but not recommended for those with weakened immune systems. Two doses provide 97% effectiveness; one dose, 93%. This means that 3 out of 100 vaccinated people exposed to measles may still catch it, though their chances of serious complications are lower.

In the U.S., advice is that the first dose should be given to babies when they are between 12 to 15 months of age and the second between four and six years old. However, the shots may be given earlier when there is a chance of exposure, such as before international travel or amidst an ongoing outbreak.

Adults who have not yet been inoculated should still receive it, and the doses are to be spaced at least 28 days apart.

The full scope of vaccines Michigan recommends are DTap (for diphtheria, tetanus, and pertussis), IPV (polio), Hib (haemophilus influenzae type B), MMR, hepatitis B, varicella (chicken pox), meningococcal, pneumococcal, and HPV.