Immunizations

The overall goal of immunizaton in children is to prevent illness and to reduce the potential for spread of communicable diseases.It becomes even more important to reduce the morbidity associated with chronic diseases and so plays an important role in care.The Red Book is published every 3 years by the American Academy  of Pediactrics and updates are provided annually in the journal  Pediatrics.The recommendations are frequently changed as new information becomes available, including better vaccines and protocols.For these reasons specific schedules for immunization will not be detailed here.It is the responsibility of the primary  care provider to ensure that the recommendations are followed and that this is modified based on the diagnosis of the chronic condition.
Immunization may be active or passive.Active immunization involves administration of all part of a microorganism (that may have been modified) to induce an immunologic response that mimics the natural  infection but does not provide a risk to the recipient.Some agents result in life-long immunity, others require re-immunization at interval.The vaccine may be and attenuated, or killed (inactivated).Passive  immunization entails administration of preformed antibody in the form of immune globulin (gamma globulin) that is derived from pooled plasma of adults.It is used to replace immunoglobins in antibody deficiency disorders, especially in congenital or acquired B-lymphocyte deffects.It is used in certain diseases to suppress a toxin (e.g.,botulism) or if a high-risk individual is exposed (e.g.,leukimia patient who is exposed to varicella).There are hyperimmune globulins that are specific so that high concentrations of the desired antibody are achieved.These include hepatitis B (HBIG), rabies (RIG), varicella-zoster (VZIG),cytomegavirus (CMV-IGIV), tetanus (TIG), and respiratory syncytial virus (RSV-IGIV).Some are given intramuscularly and some intravenously.
All immunization requires informed consent.Although they are very safe,they are not devoid of side effects.Hypersensitivity reactions are rare.Allergy to eggs has been associated with reactions to influenza and yellow fever.A history of a systemic anaphylactic reaction to egg ingestion,such as generalized urticaria,hypotension or airway obstruction, contraindicates the use of “flu or yellow fever vaccination.” MMR (neasles, mumps, and rubella) is not contraindicated by egg allergy, but 90 minutes’ observation following administration is recommended.
Children with chronic illness may require specific recommendations for immunizations.For the most part  the administration of immunization follows the recommendation for all children.Live-bacterial and live-virus vaccines are contraindicated in patient with congenital disorders of immune function.For the child who is receiving immunosuppresive therapy, the risk of the immunization is balanced with the risk of the potential illness.For example, live-virus varicella immunization in a child exposed to varicella with acute lymphocytic leukemia in remission may be justified.Inactivated vacciness and immune globulin are not risk to immune-compromised chlidren.However the immune response may be diminished with reduced efficacy of the vaccine.The Red Book provides guidelines for administration of vaccinations for children who are receiving corticostreroids.In addition, children  who are immune comprosided following transplantation, especially bone marrow, will specific recommendations for immunization.
HIV infection in children required the usual routine vaccinations of DTP, hepatitis B, and Hib expect that oral poliovaccine is contraindicated and inactived poliovirus should be given.Unless there is severe HIV immunosuppresion,MMr should be given but varicella vaccine should not be given.
Asplenic children, including those who have sickle cell disease or post-splenectomy, have an increased risk for fulminant bacteremia, which has a high mortality rate.Streptococcus pneumonia and Hemophilus influenzae  type b are the most important pathogens, but other bacterial infections and malaria are more given to all children over 2 year of age and Hib given in the schedule recommended for all children and if previously unimmunized.Meningocconal vaccine is also indicated.Many children will, receive penicillin daily for pneumonoccal prophylaxis.
Children with many chronic diseases (e.g., cystic fibrosis) are at increased risk for complications of influenza and should receive an annual “flu shot.”