Vaccination is now recognized as being one of the most important and cost effective health promotion activities. The World Health Organization (WHO) estimates that current immunization programs save more than 3.2 million lives annually and that full utilization of existing vaccines could save an additional 1.7 million lives per year.
1Vaccination as a deliberate attempt to protect humans against disease has a long history, although only in the 20th century has the practice flowered into routine use in large populations. In 1976G, Edward Jenner demonstrated that when a material was taken from a human pustular lesion caused by cowpox (i.e., an orthopox virus) and inoculated into the skin of another person, it produced a similar infection and that on recovery the latter individual was protected against smallpox after challenge. Jenner called the material vaccine from the Latin word vacca (cow) and the process, vaccination.During the last 200 years, and since the time of Jenner, vaccination helped control major diseases throughout the world and in 1977G, and for the first time in the history of man, resulted in the triumphant eradication of the old scorch smallpox. In 1974G, the Expanded Program on Immunization (EPI) was launched by the WHO. The goal of the EPI was global universal immunization of children against tuberculosis, diphtheria, pertussis, tetanus, poliomyelitis, and measles. By 1990G, and largely due to the EPI efforts, 80% of children born in the world receive these six vaccines.
1More recently, rapid advances in molecular biology made possible the development of more sophisticated vaccines. Of particular importance was a report by Burrell in 1979G of his successful cloning of hepatitis B viral antigen, 2 which opened up the possibility of producing effective and safe vaccines against a variety of diseases. Because of the large number of vaccines under development, our discussion will focus on vaccines that are commercially available.Within a relatively short period of time, the Kingdom of Saudi Arabia made great strides in its program of childhood immunization. More than 90% of school age children are completely immunized and the incidence rates of vaccine preventable diseases had decreased by more than 90% from peak levels. Conformity with the EPI program, improved standard of living and health care throughout the country, and enforcement of the Royal decree that all children must complete their immunizations before issuance of their birth certificates have resulted in the almost complete eradication of diseases that hitherto were very common. Moreover, when accumulated data showed Saudi Arabia to be endemic for hepatitis B viral (HBV) infection, health authorities acted swiftly by incorporating HBV vaccine into the routine immunization schedule of young children in 1989G. By doing this, the Kingdom became one of the very few countries in the world to have adopted universal infant HBV vaccination. The current immunization schedule that was enacted in 1991G was the product of efforts made by the Minist...