MMR Vaccine Injection is a live attenuated vaccine that provides protection against three viral diseases: Measles, Mumps, and Rubella. It is commonly used in routine childhood immunization programs to prevent outbreaks and serious complications associated with these infections.

Here are the key details:

1. Composition and Form

• Contains live attenuated strains of:

  • Measles virus

  • Mumps virus

  • Rubella virus

• Supplied as a lyophilized powder that is reconstituted with a sterile diluent before administration.

• Administered via subcutaneous (SC) injection, usually in the upper arm or thigh.

2. Mechanism of Action

• The live attenuated viruses replicate in the body without causing disease, stimulating the immune system.

• Induces production of neutralizing antibodies and cell-mediated immunity.

• Provides long-lasting immunity, often lifelong for measles and rubella, and long-term for mumps.

3. Indications

• Primary vaccination for children, typically:

  • First dose: 9–12 months of age (varies by country).

  • Second dose: 15–18 months or as per national immunization schedule.

• Catch-up vaccination for older children, adolescents, or adults who are not immune.

• Healthcare workers or travelers to areas with high risk of outbreaks.

4. Administration

• Reconstitute the lyophilized vaccine immediately before use.

• Administer subcutaneously, usually in the outer aspect of the upper arm in older children and adults, or anterolateral thigh in infants.

• Avoid intramuscular injection to preserve vaccine efficacy.

5. Side Effects

Common, mild:

• Low-grade fever.

• Mild rash.

• Swelling or redness at injection site.

• Temporary joint pain (especially in adolescent girls).

Less common:

• Febrile seizures (rare).

• Temporary lymphadenopathy.

• Mild transient thrombocytopenia.

Rare, serious:

• Severe allergic reaction (anaphylaxis).

• Encephalitis (extremely rare).

6. Contraindications

• Severe allergic reaction to a previous dose or vaccine components (e.g., gelatin, neomycin).

• Immunocompromised individuals (e.g., primary immunodeficiency, certain cancer therapies).

• Pregnancy (due to live virus).

• Moderate or severe acute illness (vaccination may be deferred).

7. Precautions

• Delay vaccination in patients receiving immunosuppressive therapy.

• Avoid giving with other live vaccines unless recommended schedules allow.

• Observe for 15–30 minutes post-injection for rare immediate allergic reactions.

• Maintain accurate vaccination records for future reference.

8. Storage

• Store the lyophilized vaccine in a refrigerator (2–8°C).

• Protect from light and freezing.

• Reconstituted vaccine should be used immediately or within the time specified by manufacturer instructions.