The overall goal of immunizations is to prevent disease. This revolution in science began with the invention of the smallpox vaccine by Jenner in 1796 and has evolved to include prevention of more than 12 diseases. The use of vaccines has actually led to the eradication of diseases (smallpox, wild-type poliomyelitis). Following the AAP and Centers for Disease Control and Prevention (CDC)–recommended immunization guidelines, however, is difficult. The CDC currently estimates that only two thirds of all 2-year-old children in the United States have received all appropriate immunizations. This can be further complicated when dealing with preterm (PT) and low-birth-weight (LBW) infants. There are many challenges to successful immunization. In fact, the increase in vaccine-preventable illnesses presents a challenge in and of itself.

Vaccine shortages pose another problem. From 2000 to 2005, there were shortages for nine of 12 of the recommended childhood immunizations. Millions of people were affected by prolonged shortages. The low supply resulted partly from a reduction in the number of manufacturers. The rising cost and financial barriers are additional challenges. Despite the increase in cost, vaccination is a cost-effective public health intervention. Unfortunately, children with fragmented health care often have incomplete immunizations.

There is also increasing public concern regarding adverse events occurring secondary to vaccination. Two of the most common public fears are: (a) the association between the measles, mumps, and rubella (MMR) vaccine and autism, and (b) thimerosal-containing vaccines and autism. In addition, the Vaccine Adverse Event Reporting System was established to scrutinize vaccine safety after U.S. Food and Drug Administration licensure. Clinicians may present a challenge when coupling medical liability concerns with vaccine administration. Public and professional lack of knowledge (schedule,
necessity) also expounds the problem. As mentioned earlier, special populations may cause increasing concerns and intensified challenges.