Do adults need 2 MMR vaccines?

The MMR vaccine protects against measles, mumps, and rubella. It is routinely given to children, with the first dose at 12-15 months of age and a second dose at 4-6 years of age. However, immunity from vaccines can wane over time. This has raised questions over whether adults need to get 1 or 2 MMR vaccines as part of routine adult immunizations.

Do adults need an MMR vaccine?

Yes, the CDC recommends that adults get at least 1 dose of MMR vaccine, with the following exceptions:

– Adults born before 1957 are considered immune as they likely had measles, mumps, and rubella as children. However, they can still get an MMR vaccine if desired.

– Adults who have lab confirmation of immunity or disease are considered protected and do not need vaccination.

– Adults who are pregnant or planning to become pregnant within 4 weeks should not get the MMR vaccine. They should wait to get vaccinated until after they have given birth.

So in summary, all adults need 1 dose of MMR vaccine, except some adults born before 1957 or who have had lab-confirmed measles, mumps or rubella already.

Why do adults need an MMR vaccine?

Adults need MMR vaccination because immunity from childhood vaccines can wane over time. Getting vaccinated again enhances immunity against measles, mumps and rubella.


– Measles: After 2 doses of measles vaccine, antibody levels remain high for decades. But up to 5% of vaccinated people lose immunity after several years. Getting a 3rd MMR dose can boost antibody levels.

– Mumps: Immunity from mumps vaccination appears to wane faster than measles or rubella. Outbreaks can still occur in vaccinated populations. An extra MMR dose improves protection.

– Rubella: Most people have long-lasting immunity after 2 doses. But 10-15% of women can become susceptible again after childbearing age. A 3rd MMR dose can reduce this risk.

So in summary, waning immunity is the main reason adults need MMR vaccination. Getting revaccinated provides stronger, long-lasting protection against all 3 viruses.

Are 2 MMR vaccines recommended for adults?

The CDC recommends 2 doses of MMR vaccine for adults who are considered “high risk” and more likely to get infected or transmit disease:

– Healthcare workers
– University students
– International travelers
– Military personnel

For routine adult vaccination, only 1 dose of MMR is recommended. Exceptions are:

– People vaccinated between 1963-1967 may have received a killed measles vaccine that was ineffective. They should be revaccinated with 2 doses of MMR.

– People vaccinated before 1979 should get a 2nd MMR dose because early rubella vaccines were not as effective.

So most adults just need 1 MMR dose. The exceptions are high-risk groups who benefit from 2 doses, and adults possibly vaccinated with ineffective products before 1979 who require 2 vaccine doses.

What are the benefits of getting a 2nd MMR vaccine?

The key benefits of getting a 2nd MMR vaccine for adults include:

– Better protection against measles and mumps – Studies show antibody levels boost several-fold after a 2nd MMR dose. This enhances immunity against disease.

– Reduced risk of rubella susceptibility – A 2nd MMR dose helps overcome waning immunity in older adults, especially women past childbearing age.

– Herd immunity – Widespread 2-dose MMR coverage in adults helps prevent transmission and protect infants too young for MMR vaccination.

– Prevention of disease outbreaks – High 2-dose MMR coverage has limited the impact of measles and mumps outbreaks in close-contact settings like colleges.

– Convenience – Getting a routine 2nd MMR combines protection against three diseases into one vaccine. It’s easier than getting separate measles, mumps and rubella shots.

So in summary, a 2nd dose mainly provides better long-term disease protection and outbreak control. The added convenience of a combination vaccine is an additional benefit.

What are the potential risks or side effects?

The MMR vaccine is very safe and well-tolerated. Side effects are generally mild. Potential adverse reactions after a 2nd MMR dose are similar to after the 1st dose:

– Sore arm at injection site (10-15% of people)
– Fever, mild rash (5-15% of people)
– Temporary joint pain from rubella component (up to 25% of adult women)
– Low platelets causing easy bruising or bleeding (1 in 30,000 doses)
– Allergic reaction with hives, swelling (rare – about 1 in 1 million doses)

Severe reactions like seizure or encephalitis are so rare that risk is unclear (maybe 1 in 3 million doses). But measles, mumps or rubella disease carries much higher risks of severe complications.

Overall, the benefits of better immunity clearly outweigh the small risks. But anyone with previous severe allergies to vaccine components should consult a doctor first.

Can MMR be given simultaneously with other vaccines?

Yes, the MMR vaccine can be safely administered at the same visit along with any other recommended vaccines like:

– Tdap (tetanus, diphtheria, pertussis)
– Shingles vaccine
– Pneumococcal vaccines
– Hepatitis vaccines
– HPV vaccine
– Meningococcal vaccine
– Influenza (flu) vaccine

Different injection sites should be used for each vaccine when possible. But even injecting multiple vaccines in one muscle is safe.

The only exception is another live vaccine like the intranasal influenza or yellow fever vaccines. Then MMR should be given either simultaneously or separated by at least 28 days.

Overall, MMR vaccination can easily be incorporated into adult immunization schedules. The flexibility makes it more convenient to administer.

At what age should adults get MMR vaccination?

The CDC recommends:

– All adults should have at least 1 dose

– High risk adults can get 2 doses starting at age 12 months, separated by at least 28 days

– Adults born in 1957 or later without evidence of immunity should get at least 1 dose

– Adults born before 1957 are presumed immune from past infection and generally don’t require vaccination

– Women of childbearing age should avoid pregnancy for 1 month after MMR vaccination

– Adults getting 2 doses should have the 2nd dose at least 1 month after the 1st dose

Otherwise, there is no maximum age limit for MMR vaccination. Protection is recommended even for older seniors if they lack evidence of immunity.

Discuss your vaccination history with your healthcare provider to determine if and when you need MMR shots.

How effective is 1 vs 2 MMR doses in adults?

One MMR dose provides effective protection in around 95% of adults:

– Measles: 95-98% protected after 1 dose

– Mumps: Around 88% protected after 1 dose

– Rubella: 95-100% protected with 1 dose

But a 2nd MMR dose boosts protection further:

– Measles: Up to 99% protected after 2 doses

– Mumps: Around 95% protected after 2 doses

– Rubella: At least 99% protected with 2 doses

So while 1 MMR dose works well, a 2nd dose does improve immunity – especially against mumps. The higher effectiveness with a 2-dose schedule helps prevent outbreaks.

How long does MMR protection last after adult vaccination?

In general, MMR immunity appears lifelong in most people after 2 vaccine doses.

– Measles: Very long-lasting immunity. Only 3-5% may be susceptible after 10+ years.

– Mumps: Immunity may wane after 10-20 years. Additional doses may be needed in adulthood.

– Rubella: Usually lifelong immunity after 2 childhood doses. But 10-15% of women can become susceptible again after age 35.

While we are still learning about long-term protection, MMR immunity clearly lasts for decades in most adults. Additional doses boost waning immunity and enhance protection throughout adulthood.

Who should not get the MMR vaccine?

The MMR vaccine is contraindicated and should not be given to:

– Anyone with severe immunodeficiency (e.g. from HIV, leukemia, lymphoma)

– Pregnant women or those planning to become pregnant within 4 weeks

– People with untreated active TB

– Those with a history of severe allergic reaction to neomycin or prior MMR dose components

– People who have received blood products or immune globulins in past 11 months

Also, anyone with moderate or severe illness, or active untreated cancer, should postpone vaccination until their health improves. Those with minor illnesses can still be safely vaccinated.

Of note, mild egg allergy is no longer considered a contraindication to the MMR vaccine. People with egg allergy can be safely vaccinated with proper precautions.

How much does adult MMR vaccination cost?

The MMR vaccine itself costs around $60-110 per dose. This vaccine cost may be covered under:

– Workplace or college vaccine requirements

– Private insurance plans

– Medicaid for low-income adults

– Medicare Part B for seniors over 65

– Self-pay at local pharmacies, health departments, or clinics

The additional costs of administration and an office visit can range from $0 at public clinics up to $150-200 at private doctor’s offices. But there are many low-cost or free options at health departments and community vaccination events.

Overall, MMR vaccination is quite affordable with multiple options for obtaining the vaccine. This helps remove cost barriers to immunization.


In summary:

– All adults should get at least 1 dose of MMR vaccine for protection against measles, mumps and rubella.

– Certain high-risk adults benefit from 2 vaccine doses for stronger immunity and outbreak control.

– The MMR vaccine is very safe and effective for long-lasting disease protection throughout adulthood.

– Vaccination is easy to get through health departments, pharmacies, clinics and doctor’s offices.

– While a 2nd MMR dose does provide better immunity, the first dose still gives adequate protection for most adults.

Discuss your situation with your healthcare provider to determine if 1 or 2 vaccine doses are right for you based on your age, risk factors, and prior vaccination history. But MMR vaccination is recommended for just about all adults without evidence of immunity to ensure protection against dangerous yet preventable viral diseases.

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