The demographic impact of increased immunisation: an initial evaluation

This paper suggests an approach towards isolating the demographic effects of recent improved immunisation programmes in two developing countries: Sri Lanka and Ghana, and considers the implications of the resulting reductions in mortality for the early 21st century populations in those countries. Economic stagnation in both countries over the last decade has provided a background against which the mortality reductions attributable to health improvements may be isolated more easily. The 1985 measles campaign in Ghana and the earlier Sri Lankan neonatal tetanus programme are chosen for the focus of analysis. +++ Researchers analyzed data from the Demographic and Health Surveys (DHSs) from Ghana (4488 women) and Sri Lanka (5865 women) to estimate the unmet need for vaccination among living children. Further, they compared data from the World Fertility Surveys with those of the DHSs to observe mortality trends. Their main goal was to identify a strategy which isolates the demographic effects of recent improved immunization programs in these 2 countries. They used life tables to make projections of deaths averted to 2025. Based on a best case scenario, the projection showed that a forecasted measles vaccination campaign in Ghana could save 459,256 lives from 1985-2025 peaking in 2000 at 17,878 lives/year. This impact would add an extra 2% to the total population size. The measles vaccination campaign would only save <1% of each year's infants and children, however. The majority of these saved lives would occur among children and not infants. The researchers also modelled the measles campaign for less developed northern Ghana. The projected campaign would save 105,000 children's lives (21% of lives saved for the whole country) and improvements in educational status would have saved 2500 of the 105,000 lives saved. A projected tetanus campaign in Sri Lanka could save 11,004 peaking in 1985 at 439 lives/year (0.12% of all infants) and decreasing to 0 by 2025. Unlike the campaign in Ghana, the impact on population growth would be 0. Nevertheless, this campaign which has been successful since its inception in 1979 would result in a 98% reduction of neonatal tetanus mortality. In conclusion, contrary to the belief that the mortality averting potential of vaccination is significant, the maximum impact of the measles and neonatal tetanue campaigns would only be moderate. Indeed socioeconomic improvements and modernization in developing countries will avert the majority of deaths in the 2000s