Rubella Vaccine

Mechanism of Action

The rubella vaccine contains live attenuated rubella virus. Live vaccines are whole-cell vaccines, meaning the entire virion is used to create the vaccine. An attenuated vaccine is a vaccine that reduces the virulence of the pathogen while still keeping it viable. This vaccine induces both humoral and cell-mediated immune responses. It produces an IgG humoral immune response in individuals, as well as a cell-mediated immune response by rubella-specific activation of CD4+ T-helper and CD 8+ T-lymphocyte cells. Thus, the immune response to a live attenuated rubella vaccine is almost identical to one seen during a natural infection.[4]

Administration

In the United States, the rubella vaccine is available only in a combined preparation. Current vaccines include measles, mumps, and rubella (MMR) without or with varicella (MMRV). Single antigen (i.e., monovalent) formulations of the rubella vaccine are not available in the United States but are available in some other countries. 

• MMR combination vaccine: MMR contains live attenuated measles, mumps, and rubella viruses. It is licensed for routine use in individuals >12 months of age and for infants >6 months of age who are traveling internationally.
• MMRV combination vaccine: MMRV is a vaccine that includes live attenuated measles, mumps, rubella, and varicella viruses. It is licensed for use in children 12 months through 12 years. 

The dose of MMR is 0.5 mL. MMR is administered subcutaneously with a 5/8 inch (1.6cm), 23 to 25 gauge needle. The site of administration of individuals >12 months of age is usually the upper outer triceps. Doses administered intramuscularly do not need to be repeated; immunogenicity appears similar in intramuscular and subcutaneous administration.[4]

In the United States, routine immunization with MMR vaccine is recommended for children at 12 to 15 months and 4 through 6 years of age.[4][5] In adults, immunity to measles and mumps may be presumed for adults born before 1957.[5] Formal documentation of immunity to rubella should be established for all women of childbearing age. Non-pregnant women who have no evidence of immunity should be vaccinated. Pregnant women with no evidence of immunity should receive the MMR vaccine as soon as possible in the postpartum period and before discharge from the healthcare facility. Repeat testing for serologic evidence of immunity after that is not required.[7]

Adverse Effects

Adverse effects of MMR and MMRV vaccines include fever, mild rash, joint tenderness, lymphadenopathy, and hypersensitivity reactions. The MMR vaccine carries a small risk of febrile seizures. Febrile seizures are rare and are not associated with long-term effects.[8][9]

Contraindications

Contraindications to the administration of the MMR vaccine include:

• Previous severe allergic reaction (e.g., anaphylaxis) after a dose of MMR or to a vaccine component (i.e., neomycin, gelatin)
• Pregnancy or attempting to become pregnant: Women should receive counsel to avoid becoming pregnant 28 days after receiving MMR because of the theoretical risk of congenital rubella syndrome. Pregnant women without immunity to rubella should receive a dose of MMR postpartum.[7]
• Immunodeficiency: Individuals with immunodeficiency are at risk for severe complications following immunization with live attenuated virus vaccines (e.g., encephalitis, pneumonitis). Immune deficiencies that are contraindications to MMR include:
• Primary acquired immunodeficiency (e.g., cellular immunodeficiency, hypogammaglobulinemia, HIV infection)
• Malignant neoplasms such as leukemia and lymphoma that affect the bone marrow or lymphatic system
• Immunosuppressive therapy. MMR should be avoided in patients receiving systemic immunosuppressive therapy just as high-dose corticosteroid therapy.    

Monitoring

Monitor the patient for both anaphylaxis and syncope for 15 minutes following administration.  

Enhancing Healthcare Team Outcomes

Routine measles, mumps, and rubella (MMR) immunization effectively prevents rubella infection, as indicated by the dramatic decline in the number of rubella cases following the introduction of vaccine programs in the 1960s.[6] Vaccination with the MMR vaccine requires an interprofessional approach involving many healthcare team members, including clinicians (MDs, DOs, NPs, PAs), nurses, and pharmacists, as the proper administration of the vaccine changes according to the patient population and the clinical scenario. Vaccination of children should follow accepted rules and vaccination schedules. By engaging in collaborative efforts and openly sharing case information (particularly the patient's vaccination record), the interprofessional team can ensure proper scheduling of all vaccines, including MMR/MMRV, thereby optimizing patient outcomes and preventing unnecessary illness. [Level 5]

One should remember that reactions to the vaccine often occur with the first rather than the second dose. Adverse effects include fever, rash, lymphadenopathy, joint complaints, hypersensitivity reactions, development of immune thrombocytopenia, and seizures.[9]

Since the rubella vaccine is a live vaccine, it is not recommended in pregnant women, and women who receive the vaccine are advised not to become pregnant for four weeks.[7] It is also used with caution at the discretion of the healthcare provider in those with prior seizures or a family history of seizures or thrombocytopenia because the vaccine carries a small risk of febrile seizures and a small risk of thrombocytopenia.[9] Additionally, it is contraindicated in individuals with a severe allergy to gelatin or the antibiotic neomycin, both of which are vaccine ingredients.

Formal documentation of immunity to rubella should be established for all women of childbearing age to decrease the incidence of congenital rubella syndrome (CRS). The recommendation is that all non-pregnant women who have no evidence of immunity should be offered a rubella vaccine. The MMR vaccine should not be administered during pregnancy due to concerns about teratogenicity. Instead, susceptible pregnant women should receive the MMR vaccine as soon as possible in the postpartum period.[7] 

However, there are no reported cases of congenital rubella syndrome in women who have received the rubella vaccine during pregnancy. Rubella can cause CRS in the newborn. CRS is the most severe sequela of rubella and the main reason the rubella vaccine was developed. About 100,000 cases of CRS occur each year. The contraction of rubella within the first trimester carries a risk of miscarriage or stillborn birth. Fetuses that survive the infection can be born with severe heart disorders, blindness, deafness, or other life-threatening organ disorders.[2] For these reasons, rubella is included in the TORCH complex of perinatal infections.

Another recommendation is a multidisciplinary approach to address misinformation and the false perception of risk associated with vaccination. In 1998 a research paper published in The Lancet authored by Dr. Andrew Wakefield claiming an association of MMR with autism spectrum disorders (ASD) and inflammatory bowel disease(IBD).[10] The claims from the paper were widely reported, leading to a sharp drop in vaccination rates in the UK and Ireland. Since the initial claim, multiple extensive epidemiological studies were undertaken that ruled out a relationship between vaccination (including the MMR) and the occurrence of ASD or IBD.[11] 

Further investigations found that Wakefield had multiple undeclared conflicts of interest, had manipulated evidence, and had conducted research in a manner that was not in accordance with medical ethics. The Lancet paper was fully retracted in 2010. The scientific consensus today is that there is no association between the MMR vaccine and ASD, and the benefits of vaccination greatly outweigh its potential risks.[12]