Vaccines and immunity

Principles of immunity were discussed in Chapter 14, whereas Chapter 16 describes a vaccination and immunization programme. 

For those infectious diseases that are transmitted to humans via insect vectors the onset and decline phases of epidemics are rarely observed other than as a reflections of the seasonal variation in the prevalence of the insect. Rather, the disease is endemic within the population group and has a steady incidence of new cases. Diseases such as these are generally controlled by public health measures and environmental control of the vector with vaccination and immunization being deployed to protect individuals (e.g. yellow fever vaccination). 

Public confidence in the safely of vaccines and immunization procedures is essential if compliance is to match the needs the community. In this respect public concern and anxiety, in the mid 1970s, over the peroeived safety of pertussis vaccine led to a reduction in coverage of the target group from ca. 80% to ca. 30%. Major epidemics of whooping-cough, with over 100000 notified cases, followed in 1977/1979 and 1981/83. By 1992, public confidence had returned, coverage had increased to 92% and there were only 4091 reported cases. 

Often the terms vaccination and immunization are used interchangeably even though they are very distinct concepts. Vaccination refers to the act of administering a vaccine, while immunization refers to the development of immunity to a pathogen. The delivery of a vaccine does not imply that the individual mounted an adequate immune response to the vaccine to elicit protection. However, immunization implies that the act of vaccination resulted in the development of protective immunity. 

Development of orphan vaccines is guided by the limited need for or markets potential of the product, with the accompanying regulations, as well as the specific characteristics of the vaccine and those who need it. After September 11th, 2001, the threats of biological attack open perspectives for acquisition of new vaccines and immune-prophylaxis products. 

Private and public funding of foundations such as the Global Alliance ifcr Vaccines and Immunization (QS), suppoted by the Bill Melinda Gates... 

State of the World s Vaccines and Immunizations World Health Organization Geneva, Switzerland, 1996. 

Different vaccines and immunization strategies have been evaluated in Denmark, Finland, Iceland, Norway, and Sweden (5). Few places outside Scandinavia have collected data on Hib immunization programs for so long (more than a decade has elapsed since universal Hib immunization was initiated in Scandinavia) and with similar accuracy. Phase 3 studies with PRP-D-Hib vaccine were done in Finland in the late 1980s, and PRP-D-Hib vaccine has been the only vaccine used in Iceland. HbOC vaccine was first compared with PRP-D-Hib vaccine in Finland and then reintroduced to the primary health-care system as the only Hib vaccine used. Finally, PRP-T-Hib vaccine was first temporarily used in Finland, and then as almost the only vaccine in Denmark, Norway, and Sweden. Besides the different conjugate vaccines, the immunization programs have differed in other aspects, such as immunization schedule and administration of vaccines (separate versus simultaneous administration with other vaccines, such as DT, DTP, DTaP, IPV, or MMR). 

A concerted effort is needed to improve communications at all levels regarding the real risks associated with vaccines and immunization and helping to reassure the public of the overwhelming safety record of vaccines. The medical community is still preeminent as advice givers to the public on matters of immunization and should play the key role in improved communication (3,6). 

Vaccines and immunizing biologicals arc covered thor-niirhlv in Chanter 7 of this text, so no lengthy discu.ssion is... 

Vaccination and immunization programmes seldom confer 100% protection against the target disease. More commonly the degree of protection is c. 60-95%. In such instances, while individuals receiving treatment will have a high probability of becoming immune, virtually all members of a community must be treated in order to reduce the actual proportion of susceptible individuals to below the threshold for epidemic spread of the dis-... 

Table 2 Internet-based vaccine and immunization resources...

A variety of resources are available for pharmacists interested in beginning a pharmacy-based immunization practice. Some of the best resource people include state health officers county health clinic physicians state department of health vaccine coordinators, especially those that administer the CHIP or KidCare-like immunization programs and local, board-certified primary care and infectious disease physicians. There are also a number of excellent web sites (see Table 2). The primary and most reliable source for vaccine and immunization information is the CDC web site. Most reliable infor mation about vaccines and immunization on other web pages is based on information first published in the public domain by the CDC in their journal, Morbidity and Mortality Weekly Report (MMWR). For those interested in keeping tabs on up-to-the-minute vaccine and immunization changes and recommendations, one should access the CDC listserv. This service forwards all issues of MMWR... 

Part 2 Validation. Geneva, Global Programme for Vaccines and Immunization, Vaccine Supply and Quality, Global Training Network, World Health Organization, 1997 (WHO/VSQ/97.02). 

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