Measles

Protection against measles

The best way to protect against measles is to get the measles, mumps, and rubella (MMR) vaccine. MMR vaccine is very safe and is effective at preventing measles, mumps, and rubella.

Most people who are vaccinated with MMR will be protected for life. Almost everyone who has not had the MMR vaccine will get sick if they are exposed to those viruses. Vaccines and high rates of vaccination have made these diseases much less common in the United States.

What if I think I was exposed?

Call your healthcare provider, tell them you have been or may have been exposed to someone who has measles, and ask them to help you check if you have protection against measles. If you become symptomatic, notify your provider of your symptoms and exposure BEFORE visiting any healthcare facility.

If you or a family member believes you may have measles or been exposed to measles:

• Stay home and contact your doctor right away. Inform them of your symptoms and concerns.

If you believe you or your family member has been exposed to measles:

• Stay home and contact your doctor immediately and let them know you were exposed to someone with measles. Inform them of your symptoms and concerns. 
• Your doctor may be able to review your vaccination history to determine if you're protected against measles.
• Avoid close contact with others, especially in public places like schools, daycare, or healthcare settings, until you've spoken to your doctor. This will help prevent the transmission of measles to others.
• If you are a healthcare provider and suspect a patient has symptoms of measles, contact RUHS-PH Disease Control immediately at (951) 358-5107.

Where can I get vaccinated?

To get vaccinated, talk to your healthcare provider or visit one of Public Health’s upcoming vaccine clinics. All clinics accept walk-in appointments. Cost and eligibility vary. For questions and clinic locations, please call (951) 358-7125 or visit www.ruhealth.org/vaccineclinics. 

Am I protected against measles?

CDC considers you protected from measles if you have written documentation (records) showing at least one of the following:

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

• A school-aged child (grades K-12)
• An adult who will be in a setting that poses a high risk for measles transmission (including students at post-high school education institutions, healthcare personnel, and international travelers)

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

• A preschool-aged child
• An adult who will not be in a high-risk setting for measles transmission

 

For international travelers, CDC considers you protected from measles if you have written documentation (records) showing at least one of the following:

You received one dose of measles-containing vaccine, and you are an infant aged 6–11 months.

You received two doses of measles-containing vaccine, and you are a person 12 months or older.

A laboratory confirmed that you had measles at some point in your life.

A laboratory confirmed that you are immune to measles.

You were born before 1957.

• A laboratory confirmed that you had measles at some point in your life.
• A laboratory confirmed that you are immune to measles.
• You were born before 1957.

Do I ever need a booster vaccine?

No. CDC considers people who received two doses of measles vaccine as children according to the U.S. vaccination schedule protected for life, and they do not ever need a booster dose.

If you're not sure whether you are fully vaccinated, talk with your healthcare provider.

I am an adult now but only got one dose of measles vaccine as a child. Do I need a second dose?

If you were born after 1957 one dose of measles vaccine is sufficient to be considered protected from measles. Certain adults may need 2 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:

• Students at post-high school education institutions
• Healthcare personnel
• International travelers
• People who public health authorities determine are at increased risk for getting measles during a measles outbreak

If you're not sure whether you are up to date on measles vaccine, talk with your healthcare provider.

Keep Reading:

MMR Vaccine Information

What should I do if I'm unsure whether I'm immune to measles?

If you're unsure whether you're immune to measles, you should first try to find your vaccination records or documentation of measles immunity. If you do not have written documentation of measles immunity, you should get vaccinated with measles-mumps-rubella (MMR) vaccine. There is no harm in getting another dose of MMR vaccine if you may already be immune to measles (or mumps or rubella). Another option is to have a healthcare provider test your blood to determine whether you're immune, but this is generally not recommended.

Do people who got the killed measles vaccine in the 1960's need to be revaccinated with the current, live measles vaccine?

Yes, people who know they got the killed measles vaccine (an earlier formulation of measles vaccine that is no longer used) should talk to their healthcare provider about getting revaccinated with the current, live measles-mumps-rubella (MMR) vaccine.

Not many people fall into this group; the killed vaccine was given to less than 1 million people between 1963 and 1967. Also, most people don't know if they got the killed vaccine during this time. If you're unsure whether you fall into this group, you should first try to find your vaccination records or documentation of measles immunity. If you do not have written documentation of measles immunity, you should get vaccinated with measles-mumps-rubella (MMR) vaccine. There is no harm in getting another dose of MMR vaccine if you may already be immune to measles (or mumps or rubella). Another option is to have a healthcare provider test your blood to determine whether you're immune, but this is generally not recommended.

 

Measles vaccine

How effective is the measles vaccine?

The measles vaccine is very effective. Two doses of measles vaccine are about 97% effective at preventing measles if exposed to the virus. One dose is about 93% effective.

How long does it take for the measles vaccine to work in your body?

For the measles vaccine to work, the body needs time to produce protective antibodies in response to the vaccine. Detectable antibodies generally appear within just a few days after vaccination. People are usually fully protected after about 2 or 3 weeks. If you’re traveling internationally, make sure to get up to date on all your measles shots. You should plan to be fully vaccinated at least 2 weeks before you depart. If your trip is less than 2 weeks away and you’re not protected against measles, you should still get a dose of measles vaccine.

How does the measles vaccine work?

When you get measles vaccine, your immune system makes protective virus-fighting antibodies against the weakened vaccine virus. Measles vaccine protects you from wild-type measles because if you have been vaccinated and then are exposed to someone with measles, your body remembers how to fight off the wild-type virus. That’s because the vaccine trained your immune system.

Could I still get measles if I am fully vaccinated?

Very few people—about three out of 100—who get two doses of measles vaccine will still get measles if exposed to the virus. Experts aren’t sure why. It could be that their immune systems didn’t respond as well as they should have to the vaccine. But the good news is, fully vaccinated people who get measles seem more likely to have a milder illness. And fully vaccinated people seem also less likely to spread the disease to other people, including people who can’t get vaccinated because they are too young or have weakened immune systems.

Exposure to measles

Call your healthcare provider, tell them you have been or may have been exposed to someone who has measles, and ask them to help you check if you have protection against measles. If you become symptomatic, notify your provider of your symptoms and exposure BEFORE visiting any healthcare facility.
 
If you or a family member believes you may have measles or been exposed to measles:

• Stay home and contact your doctor right away. Inform them of your symptoms and concerns.

 
If you believe you or your family member has been exposed to measles:

• Stay home and contact your doctor immediately and let them know you were exposed to someone with measles. Inform them of your symptoms and concerns.
• Your doctor may be able to review your vaccination history to determine if you're protected against measles.
• Avoid close contact with others, especially in public places like schools, daycare, or healthcare settings, until you've spoken to your doctor. This will help prevent the transmission of measles to others.
• If you are a healthcare provider and suspect a patient has symptoms of measles, contact RUHS-PH Disease Control immediately at (951) 358-5107.

U.S. measles cases & statistics

How common was measles in the United States before the vaccine?

Before the measles vaccination program started in 1963, an estimated 3 to 4 million people got measles each year in the United States, of which 500,000 were reported. Among reported cases, 400 to 500 died, 48,000 were hospitalized, and 1,000 developed encephalitis (brain swelling) from measles.

What are the vaccine coverage levels like in the United States?

Nationally, the rates of people vaccinated against measles have been high and stable since the Vaccines for Children (VFC) program began measuring vaccine coverage in 1994. In 2017, the overall national coverage for MMR vaccine among children aged 19–35 months was 92.7%. However, MMR vaccine coverage levels continue to vary by state, with 11 states in 2017 having MMR coverage levels of less than 90%. At the county or lower levels, vaccine coverage rates may vary considerably. Pockets of unvaccinated people can exist in states with high vaccination coverage, underscoring considerable measles susceptibility at some local levels.

Keep Reading:

Child Vaccination Coverage Reports

Some states also post their state- or local-level school vaccination coverage assessment reports online. The local data may help parents understand the risks for vaccine-preventable diseases and the benefits of vaccinations for their children.

Keep Reading:

SchoolVaxView Publications

Where do cases of measles that are brought into the United States come from?

Travelers can bring measles into the United States from any country where the disease still occurs or where outbreaks are occurring. In recent years, many measles cases came into the United States from common U.S. travel destinations.

Keep Reading:

Plan for Travel

Why have there been more measles cases in the United States in some years?

Some years, states report more measles cases compared with previous post-elimination years. CDC experts attribute this to:

Measles outbreaks in some countries to which Americans often travel, and therefore more measles cases coming into the United States.

More spread of measles in U.S. communities with pockets of unvaccinated people.

Keep Reading:

Measles Cases

What is CDC's role in responding to measles cases and outbreaks?

State and local health departments have the lead in investigating measles cases and outbreaks when they occur. CDC helps and supports health departments in these investigations by:

• Communicating with public health officials from states with reported measles cases and providing technical assistance.
• Gathering data reported by states on confirmed measles cases and evaluating and monitoring these data from a national perspective.
• Testing specimens for difficult diagnostic cases of suspected measles infection when requested by states.
• Using Advanced Molecular Detection (AMD) methods to determine measles virus genotypes and strains.
• Providing rapid assistance on the ground during outbreak investigations, often through a formal request by the state health department.
• Investing in state and local health departments for public health infrastructure and laboratory capacity to support front-line response to suspected and confirmed measles cases.
• Alerting clinicians, healthcare facilities, and public health officials around the country about current outbreaks and providing vaccine policy and clinical guidance for healthcare providers.
• Providing information to public and healthcare providers through a variety of media including the CDC website.

Keep Reading:

Measle | Surveillance of Vaccine-Preventable Diseases

For more information about Measles History, Elimination in the United States, and other information please visit Questions About Measles | Measles (Rubeola) | CDC