Epidemiology

At this time, there are no cases of measles reported in Idaho in 2025.

You can find information on past reported measles cases in the Southwest District Health region at: https://swdh.id.gov/epidemiology/

Measles spreads easily from person to person through the air. The virus can stay in the air for up to two hours after an infected person leaves a room. Unvaccinated people are at high risk if exposed.

Symptoms typically appear 11–12 days following exposure to measles.

Measles often starts with cold-like symptoms, such as:

• High fever (up to 104°F (40°C)) or higher
• Runny nose
• Inflammation and redness of the covering of the white part of the eye
• (conjunctivitis)
•  Cough
• Tiny white spots inside the mouth (Koplik spots)

Within another few days, a red rash appears:

• It often starts on the face and then spreads to the rest of the body.
• Once the rash appears, the fever may get much higher.
• This rash fades after 4 to 7 days as symptoms go away.

The symptoms of measles may look like other health problems. Make sure your child sees their healthcare provider for a diagnosis.

Common complications from measles are:

• Ear infections occur in about 1 out of every 10 children with measles.
• Diarrhea is reported in less than 1 out of 10 people with measle

Severe complications include

• Hospitalization: 1 in 5 unvaccinated people with measles in the U.S. is hospitalized.
• Pneumonia: 1 in 20 children with measles gets pneumonia — the leading cause of measles-related death in young kids.
• Brain swelling (Encephalitis): Affects 1 in 1,000 children with measles. Can cause seizures, deafness, or intellectual disability.
• Death: 1 to 3 out of every 1,000 children with measles may die from complications.
• Pregnancy risks: Measles during pregnancy can cause premature birth or low birth weight.
• SSPE (subacute sclerosing panencephalitis) is a rare but fatal brain disease that can develop years after a person recovers from measles, especially if they were infected before age 2.

Measles can be serious in all age groups. However, there are several groups that are more likely to suffer from measles complications:

Children younger than 5 years of age

Adults older than 20 years of age

Pregnant women

People with weakened immune systems, such as from leukemia or HIV infection

Measles is an airborne, extremely infectious, and potentially severe rash illness. Before the measles vaccine was introduced, an estimated 48,000 people were hospitalized and 400–500 people died in the United States each year.

Measles is not a seasonal virus. However, measles is often spread over times of high travel (like spring break) or in situations where unvaccinated persons are in close quarters (like summer camp).

The best way to prevent measles is to get vaccinated with two doses of a measles-containing vaccine, usually administered as the MMR (measles, mumps, and rubella) vaccine.

• Two doses of the MMR vaccine prevent 97 percent of measles infections.
• The vaccine protects both children and adults from serious complications.

Almost everyone without immunity will get measles if exposed to the virus. Once infected, there is no specific treatment to cure measles.

The MMR vaccine is not recommended for the following people:

• People who have had a severe allergic reaction after a previous dose or to a vaccine component
• People who have a known severe immunodeficiency
• Pregnant women

Vitamin A cannot prevent measles. Vitamin A may be useful as a supplemental treatment once someone has a measles infection, especially if they have a severe case of measles or low vitamin A levels and are under the care of a doctor.

Most people get enough vitamin A in their diet from foods like carrots, bell peppers, fish, broccoli, yogurt, and chicken. However, some people may need a supplement. Because vitamin A builds up in the body over time, there is a risk of vitamin toxicity with taking too much supplemental vitamin A. For example, during pregnancy, vitamin A toxicity can cause birth defects, so it is important to talk to your doctor before taking additional vitamin A.

The best way to prevent measles is to be vaccinated with two doses of measles vaccine. This is primarily administered as part of the MMR vaccine.

You can obtain vaccination records for your doctor’s office, the docket app on your phone or computer https://healthandwelfare.idaho.gov/immunizationrecords, or you can call your local health district.

A doctor or health care provider can test for measles with a throat or nasal swab.

Call your doctor before going in—they need to prepare so you or your child don’t expose others. It is important to let the provider know that the patient may have measles.

Isolate and avoid contact with:

• Infants
• Pregnant women
• People with weak immune systems

If you are not immune, your doctor may recommend:

• The MMR vaccine or
• A medicine called immune globulin to reduce risk.

If you do not get the vaccine, avoid places with high-risk people (schools, hospitals, child care centers) until your health care provider says it’s safe.

Stay home for four full days after the rash appears.

Avoid contact with others to prevent spreading the virus.

Ask your health care provider when it is safe to be around other people.

How to stop the spread:

• Cover your mouth and nose with a tissue when you cough or sneeze and put your used tissue in the trash can. If you don’t have a tissue, cough or sneeze into your upper sleeve or elbow, not your hands.
• Wash your hands often with soap and water.
• Don’t share drinks or eating utensils.
• Disinfect surfaces like toys, doorknobs, tables, and counters. Standard household disinfectants will readily kill the measles virus.

Rarely, vaccinated people can still get measles, but their symptoms are milder, and they are less likely to spread it.

The vaccine starts working within a few days, but full protection takes 2 to 3 weeks.

If you are traveling internationally, get vaccinated at least 2 weeks before you leave.

Children: The first dose is given at 12-15 months old, and the second dose at 4-6 years old. During a measles outbreak, the second dose can be given early to increase protection, at least 28 days after the first dose.

Unvaccinated Adults born after 1957: should get at least one dose of MMR.

People Vaccinated Before 1968: Those who got an inactivated (killed) measles vaccine or a vaccine of unknown type or who cannot provide documentation of a measles vaccine should get at least one dose of the live measles vaccine (MMR).

Travelers: People traveling internationally should have 2 doses of MMR since measles is more common in some countries.

Healthcare Workers: should have 2 doses of MMR or proof of immunity (titer)

If you have HIV/AIDS and your immune system is not too weak, you may be able to get the vaccine. Your doctor can help decide.

Check HERE for a chart regarding MMR vaccination by age.

You are considered protected from measles if you have written records showing at least one of the following:

You received two doses of the measles vaccine, and you are:

• A school-aged child (grades K-12)
• An adult in a high-risk setting, such as a healthcare worker, a college student, or an international traveler

You received one dose of the measles vaccine, and you are:

• A preschool-aged child (12 months to 4 years of age).
• An adult who is not in a high-risk setting.
• You have laboratory confirmation of a past measles infection or immunity to measles.
• You were born before 1957, as measles was very common before the vaccine was available.

No. Women who are pregnant, or planning to become pregnant within the next month, should not be vaccinated until after delivery.

Yes, it is safe to breastfeed after getting the MMR vaccine. The vaccine does not pass through breast milk, and it will not harm your baby.

No. If you had two doses as a child, you are protected for life.

Your or your child’s doctor’s office is usually the best place to receive recommended vaccines. Vaccines may also be available at pharmacies, workplaces, community health clinics, and your local health district.

Most health insurance plans cover the cost of vaccines. However, you may want to check with your insurance provider beforehand.

Measles cases in the United States often originate from unvaccinated international travelers.

Traveling to areas where measles is spreading increases your risk of exposure if you’re not protected.

Global measles situation – https://wwwnc.cdc.gov/travel/notices/level1/measles-globe

Areas in the United States with measles cases and outbreaks – https://www.cdc.gov/measles/data-research/index.html

Do not travel if you are sick.

Get the MMR vaccine at least 2 weeks before travelling.

If you travel in less than 2 weeks, you can still get one dose of MMR.

Infants (6–11 months): Get one early MMR dose.

Children (12 months and older): Get first dose now, second dose 28 days later.

Teens and adults with no immunity: Get first dose now, second dose 28 days later.

MMR vaccine is not recommended for babies under 6 months.

Watch for measles symptoms for 3 weeks after you return. Measles is very contagious and can spread to others quickly.

Call the doctor or clinic RIGHT AWAY if:

• You think you or your child have been exposed to measles.
• You or your child gets sick with a rash and fever. Tell your doctor where you traveled, and if your child got the MMR vaccine.

Avoid contact if sick. People can spread measles from 4 days before a rash develops through 4 days after the rash appears.