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Vaccines and Preventable Diseases:

MMR Vaccine Questions and Answers
Clinical Questions and Answers

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Vaccine Handling, Storage, & Injection Technique

A box of MMR vaccine (undiluted) was left at room temperature for 3 hours. Is it okay to use?

If you suspect that this vaccine or any vaccine has been mishandled, you should contact the manufacturer for guidance on its use. This is particularly important for labile live virus vaccines like MMR and varicella. Unfortunately, errors in vaccine storage and handling are common.

Once MMR vaccine has been reconstituted with diluent, how soon must it be used?

It is preferable to administer MMR immediately after reconstitution. If reconstituted MMR is not used within 8 hours it must be discarded. MMR should always be refrigerated and should never be left at room temperature.

I misplaced the diluent for the MMR dose so I used sterile water instead. Is there any problem with doing this?

Only the diluent supplied with the vaccine should be used to reconstitute any vaccine.

Can single antigen preparations for measles and rubella vaccines be mixed together? We have MMR vaccine and single antigen vaccines for those who only need one.

Absolutely not. Vaccines should never be mixed except when specifically approved by the FDA. Also, ACIP recommends use of combined MMR whenever one or more of the antigens is indicated, so there is little need to stock single antigen vaccines.

Our clinic has given MMR by the wrong route (IM rather than SC) for years. Should these doses be repeated?

All live injected vaccines (MMR, varicella, and yellow fever) are recommended to be given subcutaneously. However, intramuscular administration is not likely to decrease immunogenicity, and doses given IM do not need to be repeated.

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Vaccine Use, Recommendations, & Schedule

An 18-year-old college student says he had measles and mumps at ages 4 and 5, but never had MMR vaccine. Is rubella vaccine recommended in such a situation?

Actually, this student should receive two doses of MMR, separated by at least 28 days. (It is recommended that all persons attending school receive two doses of MMR vaccine.) A personal history of measles and mumps is NOT acceptable as proof of immunity. Acceptable evidence of measles and mumps immunity includes a positive serologic test for antibody, physician diagnosis of diseases, birth before 1957, or written documentation of vaccination. For rubella, only serologic evidence or documented vaccination should be accepted as proof of immunity. Additionally, persons born prior to 1957 may be considered immune to rubella unless they are women who have the potential to become pregnant.

I have adult patients going back to school who must show proof of MMR vaccine and are unable to retrieve their immunization records. What are my options?

Your options are to either bring the person into compliance with the school entry requirement by vaccinating or to perform serologic testing for all the antigens for which documented immunity is required. There is no evidence that adverse reactions are increased when MMR is given to a person who is already immune to one or more of the components of the vaccine.

Why is a second dose of MMR necessary?

About 2%-5% of persons do not develop measles immunity after the first dose of vaccine. This occurs for a variety of reasons. The second dose is to provide another chance to develop measles immunity for persons who did not respond to the first dose.

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If you can give the second dose of MMR as early as 28 days after the first dose, why do we routinely wait until kindergarten entry to give the second dose?

The second dose of MMR may be given as early as a month after the first dose, and be counted as a valid dose if both doses were given after the first birthday. It is convenient to give the second dose at school entry, since the child will have an immunization visit for other school entry vaccines. The risk of measles is higher in school-age children than those of preschool age, so it is important to receive the second dose by school entry. The second dose is not a "booster"; it is intended to produce immunity in the small number of persons who fail to respond to the first dose.

Do people who received MMR in the 1960s need to have their dose repeated?

Not necessarily. Persons who have documentation of receiving LIVE measles vaccine in the 1960s do not need to be revaccinated. Persons who were vaccinated prior to 1968 with either inactivated (killed) measles vaccine or measles vaccine of unknown type should be revaccinated with at least one dose of live attenuated measles vaccine. This recommendation is intended to protect persons who may have received killed measles vaccine, which was available in 1963-1967 and was not effective.

My patient has had two documented doses of MMR. Her rubella titer was nonreactive at a prenatal visit. What should I do?

It is possible that she failed to respond to both doses. It is also possible that she did respond but has a low level of antibody. Failure to respond to two properly timed doses of MMR vaccine would be expected to occur in one or two persons per thousand vaccinees, at most. A small number of people appear to develop a relatively small amount of antibody following vaccination with rubella and other vaccines. This level of antibody may not be detectable on relatively insensitive commercial screening tests. Controlled trials with sensitive tests indicate a response rate of >99% following two doses of rubella-containing vaccine. I would suggest you make a note of her documented vaccination and stop testing. Another approach would be to administer one additional dose of MMR. However, there are no data on the administration of additional doses of rubella-containing vaccine in this situation.

What is the recommendation for MMR vaccine for healthcare workers?

All persons who work in a medical facility should have evidence of immunity to measles and rubella. For most persons born after 1956, this means documentation of two doses of MMR vaccine, or serologic evidence of measles and rubella immunity. Persons born before 1957 can generally be considered immune to all three diseases, but age does not guarantee immunity. As a result, ACIP recommends that facilities consider recommending a dose of MMR to persons born before 1957 if there is no other evidence of immunity (such as serologic testing).

If a new employee in a health care setting cannot produce documentation of receiving any dose of MMR, what should be done?

Persons born in or after 1957 who work in health care facilities of any kind and cannot document prior vaccination should receive two doses of MMR separated by at least 4 weeks. Alternatively, serologic testing could determine if the person is immune to measles and rubella. Persons born before 1957 are generally considered immune to measles. However, ACIP recommends that at least one dose of MMR be considered for persons in this age group who do not have documentation of a measles-containing vaccination, history of physician-diagnosed measles, or laboratory evidence of measles and rubella immunity.

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What is the recommended length of time a woman should wait after receiving rubella (or MMR) vaccine before becoming pregnant?

Four weeks. In October 2001, ACIP voted to change its recommendation for the waiting interval following the administration of rubella vaccine. The interval was reduced from 3 months to 4 weeks. The waiting period for measles and mumps vaccine was already one month.

If a pregnant woman had a positive rubella titer in the past, and now has a negative rubella titer, she would not need another MMR vaccination. Doesn't the negative rubella titer mean her immunity has waned and she needs a booster dose?

Rubella antibody levels may decline with time, and may even fall below the level of detection of standard screening tests. However, data from surveillance of rubella and congenital rubella syndrome suggest that waning immunity with increased susceptibility to rubella disease does not occur (MMWR 1998;47[RR-8]:14). Studies of persons who have "lost" detectable rubella antibody indicate that almost all had antibody detectable by more sensitive tests, or demonstrated a booster-type response (absence of IgM antibody and a rapid rise in IgG antibody) after revaccination.

If a woman has a negative rubella titer during her first pregnancy, should she be given MMR vaccine or only rubella vaccine alone prior to hospital discharge?

She should be given MMR, unless she has documentation of immunity to measles and mumps (birth before 1957, documented vaccination, or serologic evidence of immunity).

We require a pregnancy test for all our 7th graders before giving an MMR. Is this really necessary?

No. ACIP recommends that women of childbearing age be asked if they are currently pregnant or attempting to become pregnant. Vaccination should be deferred for those who answer "yes." Those who answer "no" should be advised to avoid pregnancy for four weeks following vaccination.

Should we give an MMR to a 15-month-old whose mother is 2 months pregnant?

Yes. Measles, mumps, and rubella vaccine viruses are not transmitted from the vaccinated person, so MMR does not pose a risk to a pregnant household member.

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Contraindications & Precautions

Can I give MMR to a child whose sibling is receiving chemotherapy for leukemia?

Yes. MMR and varicella vaccines should be given to the healthy household contacts of immunosuppressed children. Oral polio is the only vaccine that should not be given to a healthy child if an immunosuppressed person resides in the household.

Is it true that egg allergy is no longer considered a contraindication to MMR vaccine?

Several studies have documented the safety of measles and mumps vaccine (which are grown in chick embryo tissue culture) in children with severe egg allergy. The AAP's "Red Book" Committee no longer considers egg allergy a contraindication to MMR vaccination. The new ACIP statement on MMR also recommends routine vaccination of egg-allergic children without the use of special protocols or desensitization procedures.

Is it contraindicated to give MMR to a breastfeeding mother or to a breastfed infant?

No. Breastfeeding does not interfere with the response to MMR vaccine. Vaccination of a woman who is breastfeeding her infant poses no risk to the infant being breastfed. Although it is believed that rubella vaccine virus, in rare instances, may be transmitted via breast milk, the infection in the infant is asymptomatic.

Can I give a PPD (tuberculin skin test) on the same day as a dose of MMR vaccine?

A PPD can be applied before or on the same day that MMR vaccine is given. However, if MMR vaccine is given on the previous day or earlier, the PPD should be delayed for at least one month. Live measles vaccine given prior to the application of a PPD can reduce the reactivity of the skin test because of mild suppression of the immune system.

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Adverse Events & Safety

A story on "60 Minutes" suggested administering each component of MMR in separate injections to decrease the risk of autism. Is there any reason to do this?

There is no scientific reason for or benefit to separating the antigens. There is no credible evidence that measles vaccine or MMR increases the risk of autism. Separating the doses puts children (and pregnant women who may be exposed to them) at increased risk for these diseases by extending the amount of time children remain unvaccinated. Studies have shown that if parents have to schedule additional appointments for vaccinations, there is an increased risk that their children may not receive all the vaccines they need. Further information about autism and vaccines is available at www.cdc.gov/ncbddd/autism/faq_vaccines.htm.

How likely is it for a person to develop arthritis from rubella vaccine?

Arthralgia (joint pain) and transient arthritis (joint redness or swelling) following rubella vaccination occurs only in persons who were susceptible to rubella at the time of vaccination. Joint symptoms are uncommon in children and in adult males. About 25% of post-pubertal women report joint pain after receiving rubella vaccine, and about 10% report arthritis-like signs and symptoms. When joint symptoms occur, they generally begin 1–3 weeks after vaccination, persist for 1 day to 3 weeks, and rarely recur. Chronic joint symptoms attributable to rubella vaccine are very rare, if they occur at all.

If a health care worker develops a rash and low-grade fever after MMR vaccine, is s/he infectious?

Approximately 5-15% of susceptible persons who receive MMR vaccine will develop a low-grade fever and/or mild rash 7-12 days after vaccination. However, the person is not infectious, and no special precautions (e.g., exclusion from work) need to be taken.

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This page last modified on May 3, 2004
Content last reviewed on January 9, 2002
Content Source: National Center for Immunization and Respiratory Diseases

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