Measles, Mumps, Rubella (MMR) Vaccine

Safety Information

Measles, Mumps, and Rubella Diseases and How to Protect Against Them

Measles causes fever, rash, cough, runny nose, and red, watery eyes. Complications can include ear infection, diarrhea, pneumonia, brain damage, and death.

Mumps causes fever, headache, muscle aches, tiredness, loss of appetite, and swollen salivary glands. Complications can include swelling of the testicles or ovaries, deafness, inflammation of the brain and/or tissue covering the brain and spinal cord (encephalitis/meningitis) and, rarely, death.

Rubella, causes fever, sore throat, rash, headache, and red, itchy eyes. If a woman gets rubella while she is pregnant, she could have a miscarriage, or her baby could be born with serious birth defects.

You can protect against these diseases with safe, effective vaccination.

Child and Adult Immunization Schedules
Get CDC’s official recommended immunization schedules for children, adolescents, and adults.

MMR Vaccine Side Effects

The Measles, Mumps, Rubella (MMR) vaccine is very safe, and it is effective at preventing measles, mumps, and rubella. Vaccines, like any medicine, can have side effects. Most people who get MMR vaccine do not have any serious problems with it. Getting MMR vaccine is much safer than getting measles, mumps, or rubella.

Common Side Effects of MMR Vaccine
  • Sore arm from the shot
  • Fever
  • Mild rash
  • Temporary pain and stiffness in the joints, mostly in teenage or adult women who did not already have immunity to the rubella component of the vaccine

MMR vaccine has been linked with a very small risk of febrile seizures (seizures or jerking caused by fever). Febrile seizures following MMR vaccination are rare and are not associated with any long-term effects. Because the risk of febrile seizures increases as infants get older, it is recommended that they get vaccinated as soon as recommended.

Some people may experience swelling in the cheeks or neck. MMR vaccine rarely causes a temporary low platelet count, which can cause a bleeding disorder that usually goes away without treatment and is not life threatening.

Extremely rarely, a person may have a serious allergic reaction to MMR vaccine. Anyone who has ever had a life-threatening allergic reaction to the antibiotic neomycin, or any other component of MMR vaccine, should not get the vaccine.

Read more in related scientific articles.

Available MMR Vaccine

There are two MMR vaccines approved for use in the United States.

  • M-M-R II [PDF – 11 pages] The Food and Drug Administration (FDA) approved this vaccine in 1971 for use in people 12 months of age and older.
  • PRIORIX [PDF – 21 pages] The Food and Drug Administration (FDA) approved this vaccine in 2022 for use in people 12 months of age and older.

The measles, mumps, rubella, and varicella (MMRV) vaccine also protects against these diseases.

How CDC Monitors Vaccine Safety

CDC and FDA monitor the safety of vaccines after they are approved or authorized. If a problem is found with a vaccine, CDC and FDA will inform health officials, health care providers, and the public.

CDC uses 3 systems to monitor vaccine safety:

A Closer Look at the Safety Data

Read more in related scientific articles.

  • Two studies (Rowhani-Rahbar et al, 2013Klein et al, 2010) indicate that for every 10,000 children who get their first MMR and varicella vaccines as separate shots when they are ages 12-23 months, about four will have a febrile seizure during the 7-10 days following vaccination. Children of the same age who get the combined measles, mumps, rubella and varicella (MMRV) vaccine as their first vaccine against these diseases are twice as likely to have a febrile seizure during the same time period.
  • Studies have shown that for children younger than 7 years old, there is a very small increased risk of febrile seizures approximately 6 to 14 days after MMR vaccination; this happens in about 1 in 3,000 to 4,000 children.
  • Joint pain is associated with the rubella portion of MMR vaccine among people who do not have immunity to rubella. Joint pain and temporary arthritis happen more often after MMR vaccination in adults than in children. Women also experience this reaction more often than men. Joint pain or stiffness occurs in up to 1 in 4 of females past puberty who were not previously immune to rubella; their symptoms generally begin 1 to 3 weeks after vaccination, are usually mild and last about 2 days. These symptoms rarely come back.
  • Immune thrombocytopenic purpura (ITP) is a disorder that decreases the body’s ability to stop bleeding. It can happen after both natural measles infection as well as after getting the MMR vaccine. However, it is usually not life threating. Treatment may include blood transfusion and medications. The risk of ITP has been shown to be increased in the six weeks following an MMR vaccination, with one study estimating 1 case per 40,000 vaccinated children.
  • Measles inclusion body encephalitis, or severe brain swelling caused by the measles virus, is a complication of getting infected with the wild-type measles virus. While rare, this disorder almost always happens in patients with weakened immune systems. The illness usually develops within 1 year after initial measles infection and has a high death rate. There have been three published reports of this complication happening to people who are vaccinated. In these cases, encephalitis developed between 4 and 9 months after MMR vaccination. In one case, the measles vaccine strain was identified as the cause.
  • Some parents might worry that the vaccine causes autism. Signs of autism typically appear around the same time that children are recommended to receive the MMR vaccine. Vaccine safety experts, including experts at CDC and the American Academy of Pediatrics (AAP), agree that MMR vaccine is not responsible for increases in the number of children with autism. Read more about vaccines and autism.

Related Scientific Articles

Jain A, Marshall J, Buikema A, Bancroft T, Newschaffer CJ. Autism occurrence by MMR vaccine status among US children with older siblings with and without autism, JAMA 2015 Apr 21:313(15):1534-40.

Krow-Lucal E, Marin M, Shepersky L, Bahta L, Loehr J, Dooling K. Measles, Mumps, Rubella Vaccine (PRIORIX): Recommendations of the Advisory Committee on Immunization Practices – United States, 2022MMWR Morb Mortal Wkly Rep. 2022 Nov 18; 71(46);1465–1470.

Rowhani-Rahbar A, Fireman B, Lewis E, Nordin J, Naleway A, et al. Effect of age on the risk of Fever and seizures following immunization with measles-containing vaccines in children. JAMA Pediatr. 2013 Dec;167(12):1111-7.

Klein NP, Fireman B, Yih WK, Lewis E, Kulldorff M, Ray P, et al. Measles-mumps-rubella-varicella combination vaccine and the risk of febrile seizures. Pediatrics. 2010 Jul;126(1):e1-8.

Mrozek-Budzyn D, et al. Lack of Association Between Measles-Mumps-Rubella Vaccination and Autism in Children: A Case-Control Study, The Pediatric Infectious Disease Journal. 2010 May; 29(5): 397-400

Baird G, et al. Measles Vaccination and Antibody Response in Autism Spectrum Disorders, Archives of Disease in Childhood. 2008 Oct; 93(10): 832-7​

Hornig M et al. Lack of Association between Measles Virus Vaccine and Autism with Enteropathy: A Case-Control Study, PLoS ONE. 2008 Sept; 3(9): e3140

Bibby AC, Farrell A, Cummins M, Erlewyn-Lajeunesse M. Is MMR immunisation safe in chronic idiopathic thrombocytopenic purpura? Arch Dis Child. 2008 Apr;93(4):354-5.

France EK, Glanz J, Xu S, Hambidge S, Yamasaki K, et al. Risk of immune thrombocytopenic purpura after measles-mumps-rubella immunization in children. Pediatrics. 2008 Mar;121(3):e687-92.

Uchiyama T, et al. MMR-Vaccine and Regression in Autism Spectrum Disorders: Negative Results Presented from Japan, Journal of Autism and Developmental Disorders. 2007; 37(2): 210-7

Doja A, and Roberts W  Immunizations and Autism: A Review of the Literature, The Canadian Journal of Neurological Sciences. 2006 Nov; 33(4): 341-6​

D’Souza Y, et al. No Evidence of Persisting Measles Virus in Peripheral Blood Mononuclear Cells from Children with Autism Spectrum Disorder, Pediatrics. 2006 Oct; 118(4): 1664-75.

Fombonne E, et al. Pervasive Developmental Disorders in Montreal and Quebec, Canada: Prevalence and Links with Immunizations, Pediatrics. 2006 July; 118(1): e139-50

Richler, et al. Is There a ‘Regressive Phenotype’ of Autism Spectrum Disorder Associated with the Measles-Mumps-Rubella Vaccine? A CPEA Study, Journal of Autism and Developmental Disorders. 2006 Apr; 36(3): 299-316

Honda H, et al. No effect of MMR withdrawal on the incidence of autism: a total population study, Journal of Child Psychology and Psychiatry. 2005; 46(6): 572-9​

Smeeth L, et al. MMR Vaccination and Perva​sive Developmental Disorders: A Case-Control Study, Lancet 2004 Sept; 364(9438): 963-9​

Klein KC, Diehl EB.  Relationship between MMR Vaccine and Autism, The Annals of Pharmacotherapy. 2004 Jul-Aug; 38(7-8):1297-300

Chen W, et al. No evidence for links between autism, MMR and measles virus, Psychological Medicine. 2004 April; 34(3): 543-53

DeStefano F et al. Age at First Measles-Mumps-Rubella Vaccination in Children with Autism and School-Matched Control Subjects: A Population-Based Study in Metropolitan Atlanta, Pediatrics 2004 Feb; 113(2): 259-66

Immunization Safety Review: Vaccines and Autism Institute of Medicine, The National Academies Press: 2004

Lingam R, et al. Prevalence of Autism and Parentally Reported Triggers in a North East London Population, Archives of Disease in Childhood. 2003; 88(8): 666-70

Makela A, et al. Neurologic Disorders after Measles-Mumps-Rubella Vaccination​, Pediatrics. 2002 Nov; 110: 957-63​

Madsen KM, et al. A Population-Based Study of Measles, Mumps, and Rubella Vaccination and Autism, New England Journal of Medicine. 2002 Nov; 347(19): 1477-82

Black C, et al. Relation of Childhood Gastrointestinal Disorders to Autism: Nested Case Control Study Using Data from the UK General Practice Research Database, British Medical Journal. 2002 Aug; 325: 419-21

Taylor B, et al. Measles, Mumps, and Rubella Vaccination and Bowel Problems or Developmental Regression in Children with Autism: Population Study, British Medical Journal. 2002 Feb; 324(7334): 393-6

Fombonne E, et al. No Evidence for a New Variant of Measles-Mumps-Rubella-Induced Autism, Pediatrics. 2001 Oct; 108(4): e58

Barlow WE, Davis RL, Glasser JW, Rhodes PH, Thompson RS, et al. The risk of seizures after receipt of whole-cell pertussis or measles, mumps, and rubella vaccine. N Engl J Med. 2001 Aug 30;345(9):656-61.

Farrington CP, et al.MMR and autism: further evidence against a causal association, Vaccine. 2001; Jun 14; 19(27): 3632-5

Miller E, Waight P, Farrington CP, et al. Idiopathic thrombocytopenic purpura and MMR vaccine. Arch Dis Child. 2001 Mar; 84(3): 227–229.

Davis RL, et al. Measles-Mumps-Rubella and Other Measles-Containing Vaccines Do Not Increase the Risk for Inflammatory Bowel Disease: A Case-Control Study from the Vaccine Safety Datalink Project, Archives of Pediatric and Adolescent Medicine. 2001 Mar;155(3): 354-9

Dales L et al. Time Trends in Autism and in MMR Immunization Coverage in California, Journal of the American Medical Association. 2001 Mar; 285(9): 1183-5 

Kaye JA, et al. Mumps, Measles, and Rubella Vaccine and the Incidence of Autism Recorded by General Practitioners: A Time Trend Analysis, British Medical Journal. 2001 Feb; 322:460-63

Bitnun A, Shannon P, Durward A, Rota PA, Bellini WJ, et al. Measles inclusion-body encephalitis caused by the vaccine strain of measles virus. Clin Infect Dis. 1999 Oct;29(4):855-61. 

Taylor B, et al. Autism and Measles, Mumps, and Rubella Vaccine: No Epidemiological Evidence for a Causal Association, Lancet. 1999; 353(9169): 2026-9  

DeStefano F, Chen RT. Negative association between MMR and autism. [Commentary] Lancet. 1999;353(9169):1987–1988. 

Peltola H, et al . No Evidence for Measles, Mumps, and Rubella Vaccine-Associated Inflammatory Bowel Disease or Autism in a 14-year Prospective Study , Lancet. 1998; 351:1327-8

Black S, Shinefield H, Ray P, Lewis E, Chen R, et al. Risk of hospitalization because of aseptic meningitis after measles-mumps-rubella vaccination in one- to two-year-old children: An analysis of the Vaccine Safety Datalink (VSD) Project. Pediatr Infect Dis J. 1997 May;16(5):500-3.

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