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• Immunization


  A process of inducing immunity artificially by either vaccination (Active) OR administration of Antibodies (Passive)
• Types of Immunization


  • Vaccination
  • Administration of Antibodies
• Vaccination


  Administration of any vaccine or toxoid for prevention of disease
• Types of Vaccines


  • Live-attenuated
  • Inactivated or killed
  • Toxoids
  • Genetically engineered
• Active Immunization


  Stimulating the immune system to produce antibodies and cellular immune responses by giving antigens
• Passive Immunization


  Providing temporary protection by administration of exogenously produced antibodies OR naturally from the mother to the child
• Immunizing agents


  • Vaccines
  • Toxoids
  • Antitoxins
  • Antibodies/Immunoglobulins
• Most immunizing agents contain preservatives, stabilizers, antibiotics, adjutants and suspending fluid
• Vaccines


  • Preparation of proteins, polysaccharides or nucleic acids of pathogens
  • Induces the body to produce antibodies and cell-mediated immunity against the specific antigen in the vaccine
• Live-attenuated vaccine


  Produces immunity by causing a mild infection. A virulent organism is weakened so that it produces an antigenic response with no serious consequences of a wild infection.
• Live-attenuated vaccines


  • BCG, Oral typhoid
  • OPV, Measles, Rubella, mumps
• Killed or Inactivated Vaccine

  Prepared from virulent organisms or preformed antigen inactivated by heat, phenol, or formaldehyde
• Killed or Inactivated Vaccines

  • Bacterial-pertussis, cholera, injectable typhoid
  • Viral- injectable polio, influenzae, rabies
• Toxoids


  Toxins which have been rendered non-toxic by treatment with formaldehyde but their antigenecity is maintained
• Toxoid vaccines


  • Diphtheria, tetanus
• Conjoined Vaccines


  Polysaccharides are being conjugated with protein because they have short-term antibody production, poor immunogenicity in infants and no memory for future antigens
• Conjoined Vaccines


  • Hib, meningococcal, pneumococcal
• Schedule of vaccines


  1. Based on: a. epidemiology of the disease

  2. age-specific risk of complications by natural disease

  3. anticipated immunologic response of the host to the antigen

  4. duration of immunity that can be induced
• Age and timing of immunization are critical for the success of vaccination
• Mandatory Vaccination Schedule


  • BCG/OPV 0 dose at 0-4 weeks
  • DPT/OPV 1 dose at 6 weeks
  • DPT/OPV 2 dose at 10 weeks
  • DPT/OPV 3 dose at 14 weeks
  • Measles vaccine/OPV 4 dose at 9 months
  • MMR at 15-18 months
  • DPT/OPV 1 booster at 18-24 months
  • DPT/OPV 2 booster at 5 years
• Vaccine Schedule Details


  • BCG 0.05ml ID (right deltoid)
  • OPV0 2 drops PO
  • DPT1 0.5ml IM
  • OPV1 2 drops PO
  • Hib1 0.5ml IM
  • HBV1 0.5ml IM
  • DPT2 0.5ml IM
  • OPV2 2 drops PO
  • HBV2 0.5ml IM
  • Hib2 0.5ml IM
  • DPT3
  • OPV3
  • HBV3
  • Hib3
  • Measles 0.5ml SC
• Minimum interval between each vaccine schedule is 4 weeks
• Even if months have lapsed between doses, just complete the course
• If mother is positive for HBsAg, HBV1 should be given at birth if possible with IG
• Vaccination schedule for a child who have not been vaccinated during infancy and still below 5 years of age

  1. BCG once (if PPD is negative)

  2. DPT & OPV today, after 4 weeks and 6th month
• Immediate goal of immunization

  • Prevent disease in individuals
• Ultimate goal of immunization

  • Eliminate/eradicate a communicable disease
• Prevention of crippling deformity (e.g. Polio)
• Maternal antibodies transferred through the placenta protect the infant up to 3-4 months AND if vaccine is given before 1 month of age, circulating antibodies may neutralize the antigens
• No antibody interference with BCG, because protection of TB depends on cell-mediated immunity so that BCG can be given at birth
• Antibodies against measles persist up to 9-12 months of age
• Premature babies are vaccinated like other babies because response to antigens is dependent on postnatal age
• Minimum interval between multiple doses should be 4 weeks
• If a vaccine is given before 4 weeks of the previous dose, it shouldn't be counted as part of the series
• Longer than recommended intervals between doses do not reduce final antibody concentration
• All EPI antigens are safe & effective if administered simultaneously (give at different sites on the same day)
• If 2 live vaccines are not given on the same day in different sites, there will be problem of interference so that they should be spaced at least 4 weeks apart
• Live vaccines shouldn't be given to severely immunocompromised children
• Deep injection and massage may reduce antigenic efficacy
• Pertussis vaccine is not recommended after the age of 6 years