Chapter 116. Immunization Principles and Vaccine Use (Part 13)

Among the valid contraindications applicable to all vaccines are a history of anaphylaxis or other serious allergic reactions to a vaccine or vaccine component and the presence of a moderate or severe illness, with or without fever. Infants who develop encephalopathy within 72 h of a dose of DTP or DTaP should not receive further doses; those who experience a "precaution" event should not normally receive further doses. Because of theoretical risks to the fetus, pregnant women should not receive MMR or varicella vaccine. Diarrhea, minor respiratory illness (with or without fever), mild to moderate local reactions to a...
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Chapter 116. Immunization Principles and Vaccine Use (Part 13) Chapter 116. Immunization Principles and Vaccine Use (Part 13) Among the valid contraindications applicable to all vaccines are a historyof anaphylaxis or other serious allergic reactions to a vaccine or vaccinecomponent and the presence of a moderate or severe illness, with or without fever.Infants who develop encephalopathy within 72 h of a dose of DTP or DTaP shouldnot receive further doses; those who experience a precaution event should notnormally receive further doses. Because of theoretical risks to the fetus, pregnantwomen should not receive MMR or varicella vaccine. Diarrhea, minor respiratoryillness (with or without fever), mild to moderate local reactions to a previous doseof vaccine, the concurrent or recent use of antimicrobial agents, mild to moderatemalnutrition, and the convalescent phase of an acute illness are not validcontraindications to routine immunization. Failure to vaccinate children because ofthese conditions is increasingly viewed as a missed opportunity for immunization. Control of Vaccine-Preventable Disease A continuing task of public health practice is to maintain individual andherd immunity, and the job is not over once a population is fully vaccinated.Rather, it is imperative to immunize each subsequent generation as long as thethreat of the reintroduction of the disease from anywhere in the world persists.Ongoing surveillance and prompt reporting of disease to local or state healthdepartments are essential to this goal, ensuring a continuing awareness of thepossibility of vaccine-preventable illness. Nearly all vaccine-preventable diseasesare notifiable, and individual case data are routinely forwarded to the CDC. Thesedata are used to detect outbreaks or other unusual events that require investigationand to evaluate prevention and control policies, practices, and strategies. International Considerations Since the establishment of the Expanded Programme on Immunization(EPI) by the WHO in 1981 and the involvement of UNICEF in the programsimplementation, levels of coverage for the recommended basic childrens vaccines(bacille Calmette-Guérin, poliomyelitis, DTP/DTaP, and measles) have risen from5% to ~80% worldwide, although coverage does not necessarily translate intoprotective immunity. Each year, at least 2.7 million deaths from measles, neonataltetanus, and pertussis and 200,000 cases of paralysis due to polio are prevented byimmunization. Despite the successes of this program, many vaccine-preventablediseases remain prevalent in the developing world. Measles, for example,continues to kill an estimated 500,000 children each year, and diphtheria,whooping cough, polio, and neonatal tetanus still occur at unacceptably high rates.An estimated 20–35% of all deaths of children are due to vaccine-preventablediseases. In addition to the antigens included in the EPI for routine use in thedeveloping world, others (hepatitis B, Hib, Japanese B encephalitis, yellow fever,meningococcal, mumps, and rubella) are used regionally, depending on diseaseepidemiology and resources. The rationale for inclusion of hepatitis B vaccine inAfrica and Asia is to prevent the subsequent development of hepatocellularcarcinoma, which is strongly linked with the persistence of hepatitis B virus fromearly childhood. The delivery of vaccines in mass campaigns on nationalimmunization days, superseding even civil wars and insurgencies, has resulted inthe cessation of transmission of poliomyelitis in the Western Hemisphere, thewestern Pacific, and Europe and in the virtual elimination of clinical measles fromthe Western Hemisphere. Periodic vaccination campaigns complement routineinfant and childhood vaccination services under the rubric catch up, follow up,and keep up. Despite these successes, concerns remain about the adequacy oflong-term strategies to ensure continuity, the impact of vaccine campaigns on theprovision of routine services, and unsafe injection practices. Because infectious diseases know no geographic or political boundaries,uncontrolled disease anywhere in the world poses a threat to the United States,even without bioterrorism. Vaccines offer the opportunity to effectively controland even eliminate some diseases through individual and herd protection.Vaccines also represent the best societal hope for stopping the pandemic of HIVinfection throughout the world and for efficiently controlling malaria andtuberculosis. Issues of cost, liability, risk, and profitability limit the interest of thepharmaceutical industry in the development of vaccines for infectious diseases ofthe poor. Sources of Information on Immunization Official vacci ...