Cost-Effective Interventions That Furthered Existing Health Systems
Even where countries have strong, functioning health systems, specific needs for new initiatives arise, perhaps because of a new disease, a serious inequity, an obstinate problem, or a generalized need for improvement. Solutions can come from within the health system, especially if that system is open to ideas, conducts research, and looks for ways to improve its performance and the health of its population. Vaccination against Haemophilus influenzae type B (Hib) in Chile offers such a story (DCP2, chapter 20).
Hib disease includes Hib meningitis, which is particularly lethal, killing 20 to 40 percent of the children who contract it and fewer of the adults who contract it and leaving half the survivors with lasting impairments such as deafness or mental retardation. Worldwide, Hib disease is the leading cause of bacterial meningitis in children under five and the second most common cause of bacterial pneumonia deaths in this age group. An estimated 450,000 children die from Hib disease each year. A highly effective, and relatively expensive, conjugate vaccine against Hib has been available since the late 1980s.
Chile is a middle-income country with a modern health infrastructure and efficient immunization services where 95 percent of infants receive routine vaccines. In the late 1980s, Ministry of Health researchers undertook the first estimates of the incidence of Hib in the Santiago area. Until that time, no information about the extent of the disease in Chile had been available. The researchers analyzed clinical and laboratory records; matched the data with census records; and assessed the quality of the data, including the probability that it understated the true extent of the disease. They concluded that Hib was a widespread problem and had a high death rate in Chile.
Even though Hib vaccines were available, they were costly, and despite substantial proof of their efficacy (their biological protective effect), less evidence of their effectiveness (impact on a large population of infants receiving the vaccine under the normal conditions of a routine immunization service) was available. Thus the Ministry of Health devised and conducted an intent-to-vaccinate study, testing a combination of Hib vaccine with the usual diphtheria-pertussis-tetanus vaccine administered at 36 health centers in the Santiago area, and compared the outcome with that at 35 centers that did not offer the Hib vaccine.
The results of this pilot program were dramatic. The study demonstrated not only that the Hib vaccine was effective but also that combining diphtheria-pertussis-tetanus and Hib vaccines and delivering them within Chile's established system was feasible for health centers. As a result, in July 1996 the Ministry of Health introduced the vaccine into the routine immunization program for babies nationwide. The incidence of Hib meningitis in Chile has fallen by 91 percent and that of pneumonia and other forms of Hib disease by 80 percent.
" combining diphtheria-pertussis-tetanus and Hib vaccines and delivering them within Chile's established system was feasible"
While the cost of the vaccine was initially substantial, the Chilean government funded it in full with public funds from general taxes. The price has since fallen from around US$15 per dose in 1996 to around US$3 in 2003. In 1998, researchers concluded that the nation saves US$78 for every case of Hib prevented, providing further evidence to support the public expenditure, which has continued.
The reasons behind Chile's success included its existing research strengths and ability to act on the results. Having a delivery system already in place, with a routine vaccine program reaching 95 percent of infants, was also key. In other words, Chile's successful Hib vaccine program was an intervention that succeeded by taking full advantage of the strengths of an already good health system.
