Prevention - Childhood Immunizations: How Are We Doing?

This chart shows childhood vaccination trends in the 1990s for five of the childhood immunizations now recommended by the American Academy of Pediatrics. (Also recommended are varicella (chicken pox) after 12 months for susceptible children, hepatitis A in certain regions and for certain high-risk groups, and pneumococcal and influenza vaccines.) This graphic demonstrates that (1) as medicine advances, more childhood vacci- nations are recommended (the latest, Hepatitis B and Haemophilus, are discussed below), and (2) a campaign to increase vaccination rates, like the one that began in 1993, leads to higher rates.

The graph shows that at the beginning of the decade, immunization rates for polio, DTP and measles ranged from 53% to 82%. DTP combines agents against diphtheria, tetanus toxoids, and acellular pertussis; MMR stands for "measles, mumps, and rubella." By the end of the decade, more than 90% of infants had received their recommended series of polio, DTP, and measles shots. "4DTP/3Polio/1MMR" constitutes the entire series of DTP, polio, and MMR vaccinations, which are administered at intervals from infancy to 35 months of age. The rate for this vaccination series went from 55% in 1992 to 80% in 1999.

The chart shows Hib immunizations at zero in 1991, just before the Hib vaccine was approved for young children. At the time, Haemophilus influenzae type b was the leading cause of bacterial meningitis (infection/inflammation of the membranes and fluid surrounding the brain and spinal cord). About 15,000 children under five got meningitis from Hib each year; about 500 died. By 1999 more than 90% of infants had gotten Hib shots. The incidence of Hib infection declined to an estimated 54 cases in 1998.

The chart shows childhood hepatitis B doses rising from 16% in 1992 to 82% in 1999. Hepatitis B virus (HBV) is a liver infection transmitted by sexual contact with an infected person or through the use of infected needles during injection drug use. About one third of chronic HBV infections are acquired around the time of birth or during early childhood and can result in chronic liver disease or liver cancer during adulthood. A vaccine developed in 1982 was recommended only for persons at high risk, including infants born to infected mothers. Unfortunately, infected individuals seldom seek medical attention, and it became apparent that prevention could not be achieved by immunizing only those at risk. A new, long-term strategy to prevent HBV is now aimed at all infants.

In 1993 universal childhood immunization became a legislative priority and the passage of the Childhood Immunization Act brought about the highest vaccination rates in history. The result was a decline in the incidence of all vaccine-preventable diseases except whooping cough (pertussis).

What led to the campaign to get more infants and children immunized? The measles epidemic of 1989-1991 may have had something to do with it. During this two-year period, more than 55,000 children succumbed to measles and more than 150 children died. A CDC investigation found that the epidemic started among pre-school-age children. Fewer than two thirds of them were fully vaccinated, while most older children were protected because state laws required vaccination for school entry. The CDC also found that immunization rates for low-income, minority children were lower than the national average, with the result that the number of epidemic measles cases among Hispanic and African- American populations was four to seven times higher than among non-Hispanic whites.

One might ask: If a way is known to prevent a disease, what stands in the way of implementing it? Politics is blamed. For example, it was alleged that Reagan administration cost-cutters saw rates of preventable diseases declining and cut funding for immunizations. Parents are blamed. Medical advances lead to increasingly complex vaccination schedules; many parents fail to get their children immunized until forced to do so by schools. Vaccine manufacturers are blamed. Fear of lawsuits drove some manufacturers out of the vaccine business; prices went up and shortages occurred.

Adverse reactions to vaccines happen — for example, between eight and 10 cases of vaccine-related paralytic polio are still reported in the United States each year. The National Vaccine Injury Compensation Program (1988), which assists the families of victims, is a no-fault alternative for resolving claims. Adverse reactions, although rare, have sparked a small but vocal anti-immunization movement. Joining this movement are those who oppose immunization for religious, philosophical, or other reasons.

Source: Chart: National Center for Health Statistics, Healthy People 2000 Final Review, Table 20, retrieved June 13, 2002, from http://www.cdc.gov/nchs/. Mary Graham, "Public Health: Unprotected Children," Atlantic Monthly, March 1993. Linda A. Moyer and Eric E. Mast, "Hepatitis B: Virology, Epidemiology, Disease, and Prevention," American Journal of Preventive Medicine, Oct. 1994, p45-55. Gretchen Flanders, "Vaccinations: Public Health's 'Miracle' Under Scrutiny," State Legislatures, March 2000, p20+.