Vaccine Info

M-M-R II Vaccine

Last Reviewed
January 3, 2021

M-M-R II Vaccine Description

Merck's M-M-R II vaccine is known as the Measles, Mumps, and Rubella Virus Vaccine Live, containing weakened forms of measles virus, mumps virus, and rubella virus. The M-M-R II vaccine works by helping the immune system protect itself from these viruses, says the company.

The vaccine's active ingredients include weakened forms of the measles, mumps, and rubella (MMR) viruses. The inactive ingredients include sorbitol, sucrose, hydrolyzed gelatin, recombinant human albumin, fetal bovine serum, other buffer and media ingredients, neomycin.

Clinical studies of 284 triple-seronegative children between 11 months to 7 years of age demonstrated that M-M-R II is highly immunogenic and generally well-tolerated. In these studies, a single injection of the vaccine-induced measles hemagglutination-inhibition (HI) antibodies in 95% of the participants, mumps neutralizing antibodies in 96%, and rubella HI antibodies 99% of susceptible persons.

However, a small percentage (1%-5%) of vaccinees may fail to seroconvert after the primary dose. The most common side effect of vaccination with M-M-R II is pain at the shot site for a short time. Other side effects may include fever or rash.

The MMR vaccine was developed by Maurice Hilleman and was licensed for use by Merck in 1971.

M-M-R II Vaccine Indication

The vaccine is indicated for simultaneous vaccination against measles (rubeola), mumps, and rubella (German measles). This vaccine is usually given to people 1-year of age or older.

M-M-R II is contraindicated in certain individuals, including those with: a history of hypersensitivity to any component of the vaccine, including gelatin; a history of anaphylactic or anaphylactoid reaction to neomycin; blood dyscrasias, leukemia, lymphomas of any type, or other malignant neoplasms affecting the bone marrow or lymphatic systems; primary or acquired immunodeficiency conditions; family history of congenital or hereditary immunodeficiency or receiving immunosuppressive therapy; an active febrile illness; or those who are pregnant.

And, if vaccination of postpubertal females is undertaken, pregnancy should be avoided for 3-months following vaccination.

M-M-R II Vaccine Dosage

The U.S. CDC's ACIP committee recommends administering the 1st dose of M-M-R II at 12 to 15 months of age and administering the second dose of M-M-R®II at 4 to 6 years ago.

The M-M-R II vaccine is given as a shot administered subcutaneously, preferably into the arm's outer aspect. The dose of the vaccine is the same for everyone. If your child gets the shot when he or she is one year old or older, a second dose is recommended.

Often, the 2nd dose is given right before the child goes to elementary school (4 to 6 years of age). If your child is less than one year old when he or she first gets the shot, a second dose should be given when 12 to 15 months old. If a 3rd vaccination is prescribed, a dose should be given between 4 and 6 years of age.

M-M-R II Vaccine News

December 25, 2020 - Washington DC legislation: B23-0171 - Minor Consent for Vaccinations Amendment Act of 2019. BILL SUMMARY - As introduced, this bill permits a minor of any age to consent to receive a vaccine where the vaccination is recommended by the US Advisory Committee on Immunization Practices. It also establishes that if a minor can comprehend the need for, the nature of, and any significant risks inherent in medical care, informed consent is established.

December 17, 2020 - In this study, researchers focused on the first MMR vaccination because they hypothesized that any changes in vaccination rates due to COVID-19 pandemic-related closures likely would be identified earliest among young children who require frequent preventive visits. From March 2017 to March 2020, the average proportion of 16-month-old children with MMR vaccination was 72.0%, which decreased to 62.4% (P = .02) by August 2020. It is too soon to evaluate whether there has been a decrease related to the second MMR vaccination. Despite efforts to have families return for preventive care, the AAP says there is a need for novel strategies to ensure the delivery of comprehensive preventive services, including catch-up vaccination efforts that might need to extend beyond the end of the pandemic to protect our community from vaccine-preventable outbreaks.

December 16, 2020 - A new study published in Nature by a team led by researchers from the Institute for Health Metrics and Evaluation at the University of Washington found MCV1 coverage estimates show overall progress from 2000 to 2019. Moreover, 62 out of 101 countries in the study increased national-level MCV1 coverage while reducing subnational geographical inequalities over time, which is a noteworthy achievement.

December 1, 2020 - The Journal Pediatrics published a study found in Ohio, from March 2017 to March 2020, the average proportion of 16-month-old children with MMR vaccination was 72.0%, which decreased to 62.4% in August 2020.

November 30, 2020 - Study: the bivalent MeV/SARS-CoV-2 vaccine candidate has several desirable properties concerning its immunogenicity and efficacy against SARS-CoV-2. Furthermore, the concurrent induction of anti-MeV immunity would allow its use in the context of routine measles immunization schedules. Such a MeV-based COVID-19 vaccine could be included in the currently applied MMR (measles, mumps, rubella) vaccine, providing additional protection against SARS-CoV-2.

November 20, 2020 - Study: Analysis of Measles-Mumps-Rubella Titers of Recovered COVID-19 Patients. These results demonstrate a significant inverse correlation between mumps titers from MMR II and COVID-19 severity. This study's significance is that it showed that mumps titers related to the MMR II vaccine are significantly and inversely correlated with the severity of COVID-19-related symptoms, supporting the theorized association between the MMR vaccine and COVID-19 severity.

October 23, 2020 - Vaccination Coverage by Age 24 Months Among Children Born in 2016 and 2017 — National Immunization Survey-Child, United States, 2017–2019.

October 23, 2020 - A study published in the American Journal of Medicine suggested 'the MMR vaccine may protect against COVID-19, including high-risk individuals, such as the elderly with comorbidities, and health care workers and first responders with COVID-19 patients, especially individuals living in long-term care facilities and the related institutional staff.' These findings suggest the MMR vaccine may protect against COVID-19, including high-risk individuals, such as the elderly with comorbidities, and health care workers and first responders with COVID-19 patients, especially individuals living in long-term care facilities and the related institutional staff. Clinicians caring for such high-risk patients should consider the benefit/cost ratios of MMR vaccination to justify using this simple, low-risk intervention to reduce COVID-19 disease, especially until a specific vaccine is approved.

October 14, 2020 - A research team led by Dr. Larenas-Linnemann, working at Medica Sur, Mexico City, reported their clinical observations in 255 subjects vaccinated measles-mumps-rubella (MMR) vaccine since the start of the COVID-19) pandemic. The concept of trained immunity based on a heterologous immune response with nonspecific memory dates back about a decade ago. It refers to the enhanced immune response to a certain pathogen after being exposed (by vaccination or natural illness) to another nonrelated pathogen1. Matricardi analyzed this in the context of the COVID‐pandemic. Conclusive evidence of the value of MMR vaccine to reduce COVID-19 complications requires a prospective, randomized trial.

October 11, 2020 - The two measles vaccination campaigns in the Central African Republic appear to have been largely successful in slowing the measles outbreak that was declared at the start of 2020. However, children aged 6 months to 10 years will have received only one dose of measles vaccination. The lack of a second dose has led to declining immunity elsewhere in the region, which needs to be considered when planning future activities.

October 7, 2020 - The Philipines Department of Health and Local Government Units will conduct nationwide measles, rubella, and polio supplemental immunization activity starting October 26, 2020. In the Philippines, an estimated 2.4M children under five are susceptible to the measles virus.

September 23, 2020 - BMJ commentary: Containing measles in conflict-driven humanitarian settings

According to CDC immunization schedules, September 15, 2020 - All travelers to Africa, including infants and pre-school aged children, should be fully vaccinated against measles.

September 3, 2020 - Global trial to test whether the MMR vaccine protects front-line health-care workers against COVID-19.

September 3, 2020 - An international research network announced it is launching the CROWN CORONATION phase 3 clinical trial to evaluate whether the vaccine for measles, mumps, and rubella (MMR) can protect front-line health-care workers against infection from SARS-CoV-2, the virus that causes COVID-19.

September 1, 2020 - A study was published in The Lancet: Immunogenicity and persistence of trivalent measles, mumps, and rubella vaccines: a systematic review and meta-analysis.

July 30, 2020 - The Lancet published: Persistence of US measles risk due to vaccine hesitancy and outbreaks abroad.

June 19, 2020 - A  study published in the journal mBio suggests that the measles, mumps, rubella (MMR) vaccine could reduce the inflammation associated with COVID-19 disease. These researchers stated: 'There is mounting evidence that lives attenuated vaccines provide nonspecific protection against lethal infections unrelated to the target pathogen of the vaccine by ... inducing “trained” nonspecific innate immune cells for improved host responses against subsequent infections.'

May 20, 2020 - The MMR Vaccine Appears to Confer Strong Protection from COVID-19: Few Deaths from SARS-CoV-2 in Highly Vaccinated Populations. Published epidemiological data suggest a correlation between patients who receive measles-rubella containing vaccines such as the commonly available MMR vaccine and reduced COVID-19 death rate. Similar observations were recently noted in a Cambridge Study by Young et al., who noted protein homology between the COVID-19 virus and the rubella virus, corroborating this report's evidence. The epidemiologic associations suggest that a measles-rubella containing vaccine, as currently produced, may be protective against severe disease and death from COVID-19 exposure.

According to a report published Monday, May 18, 2020 - Routine vaccinations for young children in the U.S. fell during the first half of this year as more Americans skipped routine doctor visits due to the coronavirus pandemic by the Centers for Disease Control and Prevention. 

May 3, 2020 - The report MMR Vaccine Link to COVID-19: Fewer Deaths and Milder Cases from SARS-CoV-2 in Measles-Rubella Vaccinated Populations reveals that the MMR vaccine launched in 1971 (49 years ago) could explain why those 49 and under are much less likely to have bad outcomes from COVID-19 compared to those 50 and over, according to report co-contributor Dr. Larry P. Tilley, an Advisory Board Member of World Organization.

April 28, 2020 – Public health officials in Mexico have identified a measles virus outbreak in various states in Mexico.

April 27, 2020 – A new review of the existing evidence on the safety and effectiveness of measles-related vaccines supports their continued use for mass immunization worldwide.

April 10, 2020 - A non-peer-reviewed study stated, 'As an initial test of this hypothesis, we identified that 1.) age groups that most likely lack MMR vaccine-induced immunity had the poorest outcome. COVID-19, and 2.) COVID-19 disease burden correlates with rubella antibody titers, potentially induced by SARS-CoV2 homologous sequences. Therefore, we propose that vaccination of ‘at risk’ age groups with an MMR vaccination merits further consideration as a time appropriate and safe intervention.'

M-M-R II Vaccine Clinical Trials

Clinical Trial NCT01702428: Consistency Study of GlaxoSmithKline (GSK) Biologicals' MMR Vaccine (209762) (Priorix) Comparing Immunogenicity and Safety to Merck & Co., Inc.'s MMR Vaccine (M-M-R II), in Children 12 to 15 Months of Age. Last Update Posted: November 25, 2019.

ClinicalTrial NCT04333732: CROWN CORONATION: COVID-19 Research Outcomes Worldwide Network for CORONAvirus prevenTION (CROWN CORONA). CROWN CORONATION is an international, Bayesian platform adaptive, randomized, placebo-controlled trial assessing candidate interventions' effectiveness in preventing COVID-19 disease in healthcare workers. Randomization will be stratified by age (<50 and ≥50) and site. Participants will be healthcare workers at risk of contracting SARS-CoV-2. Last Update Posted: November 23, 2020.

Measles, Mumps, and Rubella FAQs

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