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Health, immunization and economic growth
Research Briefing 1:
Health and Economic Growth
Common sense might suggest
that a healthy person is likely to be more productive than
an unhealthy one, both in paid work and in the maintenance
of a home and the raising of healthy children. But for years,
hard evidence to support that common sense remained elusive.
Now, the situation is changing. Two broad types of research
point to an increasingly clear link between improvements in
peoples health and economic growth. The first type of
research is the comparison of different countries performance
over time, using indicators such as mortality rates and gross
domestic product (GDP). The second type of research is at
the level of households and individuals, investigating the
links between peoples health and their productivity
and earnings.
International comparisons
Researchers have long
tried to disentangle the factors that might account for the
wide variations in per-capita income between different countries.
They have analysed the impact of factors such as education
levels and training investments, and shown, for example, that
the more educated a population, the better its income. Surprisingly,
perhaps, they have until recently paid less attention to the
effects of health improvements. As data have improved during
the 1980s and 1990s, however, it is becoming increasingly
clear that a real relationship exists between a nations
burden of disease and its income(1).
One key indicator of
a populations health status is life expectancythe
age to which a newborn baby can expect to survive. Life expectancy
at birth has increased sharply worldwide over the past half-century,
but remains below 50 years in many of the worlds poorest
countries where the burden of infectious diseases remains
heavy. Recent studies have shown that life expectancy, or
survival rate, is a powerful predictor of income level and
of economic growth. For example, an analysis of data for 53
countries between 1965 and 1990 found that overall, the improvement
in adult survival rates was responsible for about eight per
cent of total growth (2). The researchers who performed
this analysis suggest that three broad mechanisms are responsible
for this effect: (a) improvements in productivity due to a
healthier workforce and less absenteeism; (b) the increased
incentives that both individuals and firms have to invest
in human and physical capital as life expectancy increases;
and (c) the increase in savings rates, as workers have an
incentive to save for retirement.
In Mexico, studies
supported by the Pan American Health Organization, the Inter-American
Development Bank and others have added further weight to the
evidence. The studies indicate that, if male life expectancy
increases by one year, the gross domestic product of the country
will be increased by an additional 1 per cent after 15 years(1).
Another health indicator
that is correlated with economic performance across countries
is the total fertility rate, or birth rate. As a populations
health improves, more of its infants and young children survive.
This tends to lead, over time, to a fall in fertility rates.
Several studies have shown that, soon after crude birth rates
fall, economic growth increases, as the proportion of the
population participating in the labour force swells. Of course,
this "bulge" in the structure of a national population, leading
to a temporary "demographic gift" of young adults, does not
automatically lead to growth, nor is growth necessarily permanent.
In East Asia, a rapid decline in infant mortality in the 1940s
and a subsequent fall in fertility led to a rapid relative
increase in the number of adults of working age in the regions
population, compared with the very young and very old. One
study suggests that between one-third and one-half of the
regions growth during the period 1965 to 1990its
"economic miracle"may have been due to these demographic
changes. (3) Some researchers now argue that subsequent
population aging is contributing to the recession in East
Asia.
Climate, through its
effects on health, may also influence economic development.
Several lines of evidence indicate that countries in tropical
regions are at an economic disadvantage, in part because of
endemic malaria. Although much more work is needed to measure
more precisely the effects of malaria on national economies,
one study questions whether malaria may be a cause of poverty
as much as a consequence of it. In countries where a high
proportion of the population is at risk of severe malaria,
measured on a standard index, average income per capita in
1995, adjusted for purchasing power, was less than one-fifth
that of non-malarial countries. Income growth per capita since
the mid-1960s for countries with severe malaria has been only
0.4 per cent per year, compared with 2.3 per cent in other
countriesa difference of more than fivefold. (4)
Households
and individuals
In the worlds
poorer countries, the burden of infectious diseases and malnutrition
remains heavy and falls disproportionately on children. Five
major childhood conditionsdiarrhea, pneumonia, malaria,
measles and perinatal conditionsare between them responsible
for more than one-fifth of all deaths in low-income and middle-income
countries1. Researchers are now beginning to ask
whether these conditions, which are found almost exclusively
among the worlds poor, may also have a personal and
economic impact on survivors. Adults health may suffer
the longterm effects of childhood illness and malnutritionsuch
as blindness or stunting. And parents whose children are repeatedly
sick, for example from malaria, may be less able to work efficiently
and hold down jobs.
Studies of the economic
impact of household health are difficult to do and their broad
conclusions were initially unclear. But with increasing sophistication,
these studies have begun to show a consistent pattern. A review
of the literature finds that sick workers are absent from
work more than healthy workers, even when they are self-employed.
And, on balance, the review concludes, some dimensions of
health do clearly affect workers productivity(5).
The effects of ill
health on individual productivity appear to be greater in
poor populations than in rich ones. This is partly because
of the typical nature of poorer peoples work. Poorer
and less educated individuals are more likely to have jobs
that require physical fitness and stamina, while more affluent
and educated individuals jobs may be more sedentary.
A growing number of
studies suggest that health does influence earnings. In Brazil,
for example, one study found that a 1 per-cent increase in
mens heighta measure that partly reflects childhood
health and nutritionwas associated with an increase of almost
8 per cent in wages. Taller menand also womenwere
also more likely to participate in the labour force than shorter
men and women. While no one claims that the relationship between
height and income should be interpreted simplistically, the
findings do suggest that a healthy childhood may have at least
some bearing on adult productivity in poorer economies. Also,
some studies suggest that in malnourished adults, a change
to a diet with higher calories and greater protein content
results in increased productivity.
The relationship between
peoples health and their earnings must be studied more
thoroughly and on a larger scale before researchers can reach
precise conclusions about how these two factors interact.
But, compared with even a decade ago, there is now increasingly
robust evidence that improvements in the health of the poorest
households can provide an escape route out of the poverty
trap.
References
1. World Health Report,
1999: Making a Difference. WHO 1999 see www.who.int/whr
2. Jamison DT, Lau
LJ, Wang J. Healths contribution to economic growth,
1965-90. IN: Health, Health Policy and Economic Outcomes.
Health and Development Satellite, Final Report.WHO Director-General
Transition Team, 1998.
3. Bloom DE, Williamson
JG. Demographic transitions and economic miracles in emerging
Asia. The World Bank Economic Review, 1998, 12(3): 419-455
4. Gallup JL and Sachs
JD. The Economic Burden of Malaria: Cross-Country Evidence.
IN Health, Health Policy and Economic Outcomes. Health and
Development Satellite, Final Report.WHO Director-General Transition
Team, 1998.
5. Strauss J and Thomas
D. Health, Nutrition and Economic Development. Journal of
Economic Literature. Vol XXXVI (June 1998) 776-817.
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