MEASLES AND RUBELLA VACCINE (LIVE), (ATTENUATED, FREEZE DRIED)-10 DOSES

Dosage

Children: Refer to the BNF for Children for appropriate pediatric dosing guidance.

Adults: Refer to the relevant drug monograph or clinical guidelines for adult dosing information.

Mechanism of action

Doses work through various mechanisms depending on the specific drug class it belongs to. Generally, this may involve receptor binding, inhibition of enzyme activity, or modulation of ion channels, leading to therapeutic effects in the body. Key pathways may include neurotransmitter modulation, hormonal regulation, or alteration of cellular signaling cascades.

Pharmacodynamics

The pharmacodynamics of doses involves the relationship between drug concentration and its pharmacological effect. This can include agonistic or antagonistic actions at specific receptors, modulation of metabolic pathways, or effects on physiological systems. The therapeutic window, efficacy, and potential side effects are integral to understanding how doses impact clinical outcomes.

Pharmacokinetics

Pharmacokinetics refers to the absorption, distribution, metabolism, and excretion (ADME) of doses. Factors such as bioavailability, half-life, volume of distribution, and clearance rates play a critical role in determining the appropriate dosing regimen for patients. Variability in these parameters can occur based on individual patient characteristics, including age, kidney and liver function, and concomitant medications.

Pregnancy

Refer to relevant guidelines and consult a healthcare professional for specific advice regarding use during pregnancy.

Breast-feeding

Consult a healthcare professional as the safety during breastfeeding may vary based on the drug.

Storage

Store in a cool, dry place, away from direct sunlight and moisture. Keep out of reach of children.

Indications

• Prevention of measles through vaccination
• Management of measles infection in symptomatic patients
• Prevention of complications associated with measles infection

Dosage

Children: Refer to local vaccination guidelines for measles immunization recommendations.

Adults: Refer to local vaccination guidelines for measles immunization recommendations.

Mechanism of action

The measles virus enters host cells through the interaction of its hemagglutinin (H) protein with the CD150 (SLAM) receptor on the surface of immune cells. Following entry, the viral RNA is released into the cytoplasm, leading to the replication of the viral genome and the production of viral proteins. The newly formed virions are then released from the host cell, allowing the virus to spread to adjacent cells.

Pharmacodynamics

Measles virus infection leads to a robust immune response, resulting in the activation of both humoral and cellular immunity. The disease is characterized by an initial immune suppression, followed by a strong immune response that typically clears the virus. However, this immune suppression can leave the host vulnerable to secondary infections.

Pharmacokinetics

As a virus, measles does not have pharmacokinetic properties in the traditional sense, as it does not undergo metabolism or elimination like a drug. Instead, the virus's lifecycle involves attachment, entry, replication, and release from host cells. The duration of viral shedding can last for several days before the appearance of the rash.

Contra-indications

• Severe allergic reaction to a previous dose of measles vaccine
• Severe immunodeficiency (e.g., in patients with HIV/AIDS, or those receiving high-dose immunosuppressive therapy)
• Pregnancy (in certain live vaccines, including measles)

Adverse effects

• Fever
• Rash
• Diarrhea
• Otitis media
• Pneumonia
• Encephalitis (rare)

Interactions

• Live attenuated vaccines should not be administered simultaneously with immunoglobulins (e.g., anti-rabies serum) as they may interfere with the immune response
• Corticosteroids may reduce the immune response to the vaccine

Precautions

• Assess for history of severe allergic reactions
• Monitor for signs of respiratory distress in patients with a history of asthma or other respiratory conditions
• Consider vaccination timing in patients with recent blood transfusions or immunoglobulin administration

Pregnancy

Measles vaccination is contraindicated during pregnancy due to potential harm to the fetus. Women should be advised to avoid pregnancy for a month after receiving the vaccine.

Breast-feeding

Measles vaccination is generally considered safe during breastfeeding, though it is recommended to consult healthcare providers for individual cases.

Storage

Store in a refrigerator at 2°C to 8°C, do not freeze. Protect from light.

Formulations

• Measles vaccine (live attenuated)
• Combination measles, mumps, rubella (MMR) vaccine

Indications

• Prevention of rubella infection through vaccination
• Screening and management of congenital rubella syndrome in newborns
• Public health measures to control rubella outbreaks

Dosage

Children: For vaccination, the MMR vaccine is typically administered to children at ages 12-15 months and a second dose at 4-6 years.

Adults: For vaccination, a single dose of the MMR (measles, mumps, rubella) vaccine is recommended for adults who have not been previously vaccinated or who lack immunity.

Mechanism of action

The rubella virus enters the body through the respiratory tract and replicates in the nasopharynx and regional lymph nodes. It then spreads to the bloodstream and other tissues, leading to a systemic infection. The immune response to the virus, including the production of IgM and IgG antibodies, is responsible for the clinical manifestations of the disease.

Pharmacodynamics

The rubella virus is a single-stranded RNA virus that belongs to the Togaviridae family. After infection, the virus induces an immune response that includes both humoral and cellular immunity. The resulting antibody production provides long-lasting immunity to reinfection. The clinical symptoms, such as fever and rash, are primarily due to the immune response rather than direct viral damage.

Pharmacokinetics

The incubation period for rubella is typically 14 to 21 days. The virus is present in the nasopharynx and urine. The immune response develops within a few days of infection, leading to the production of antibodies. The presence of IgM antibodies indicates an acute infection, while IgG antibodies indicate past infection or vaccination. The virus is usually eliminated from the body within a few weeks, but immunity persists for life following infection or vaccination.

Contra-indications

• Hypersensitivity to rubella vaccine components
• Pregnancy in women who have not been vaccinated or infected previously

Adverse effects

• Mild fever
• Rash
• Joint pain
• Lymphadenopathy
• Transient thrombocytopenia

Interactions

• Live attenuated vaccines may interfere with each other
• Immunosuppressive therapies may reduce vaccine efficacy

Precautions

• History of anaphylactic reactions to neomycin or gelatin
• Individuals with severe immunodeficiency should not receive live vaccines
• Pregnant women should avoid conception for at least one month after vaccination

Pregnancy

Rubella vaccination is contraindicated during pregnancy due to potential harm to the fetus. Women are advised to receive the vaccine before conception.

Breast-feeding

Rubella vaccination is considered safe during breastfeeding.

Storage

Store at 2 to 8 degrees Celsius. Do not freeze. Protect from light.

Formulations

• Live attenuated rubella vaccine

Indications

• Prevention of infectious diseases such as measles, mumps, rubella, hepatitis B, influenza, and human papillomavirus (HPV)
• Travel vaccinations for diseases endemic to certain regions
• Vaccination for at-risk populations, such as those with compromised immune systems or specific occupational exposures

Dosage

Children: Dosage varies by vaccine type and age; refer to the BNF for Children for specific dosing information.

Adults: Dosage varies by vaccine type and indication; refer to specific guidelines for each vaccine.

Mechanism of action

Vaccines work by mimicking an infection. They introduce a harmless component of a pathogen (antigen) to the immune system, prompting the body to produce an immune response. This includes the generation of antibodies and memory cells that provide long-term immunity. Upon subsequent exposure to the actual pathogen, the immune system is primed to respond more rapidly and effectively.

Pharmacodynamics

The pharmacodynamics of vaccines involves the activation of both humoral and cellular immunity. Vaccines stimulate B cells to produce antibodies against the pathogen, while T cells are activated to destroy infected cells. This dual response helps to establish immunological memory, which enables a faster and more robust response upon re-exposure to the pathogen.

Pharmacokinetics

Vaccines are administered via various routes, including intramuscular, subcutaneous, and oral. After administration, the antigens are presented to antigen-presenting cells, which activate T cells and stimulate B cell proliferation and differentiation. The half-life of vaccine-induced immunity varies depending on the type of vaccine, with some providing lifelong immunity and others requiring booster doses to maintain protection.

Contra-indications

• Severe allergic reaction (anaphylaxis) to a component of the vaccine
• Severe immunocompromised state for live attenuated vaccines

Adverse effects

• Local reactions at the injection site (pain, redness, swelling)
• Fever
• Fatigue
• Headache
• Muscle pain
• Joint pain
• Nausea

Interactions

• Immunosuppressive medications may reduce vaccine efficacy
• Concurrent administration of some vaccines may require spacing to optimize immune response

Precautions

• History of allergic reactions to vaccines or vaccine components
• Pregnancy (specific vaccines may be contraindicated)
• Moderate to severe acute illness with or without fever

Pregnancy

Consult healthcare provider. Some vaccines are contraindicated during pregnancy, while others are recommended.

Breast-feeding

Generally considered safe, but consult healthcare provider regarding specific vaccines.

Storage

Store in a refrigerator at 2-8°C. Do not freeze. Protect from light.

Formulations

• Liquid suspension for injection
• Lyophilized powder for reconstitution