|
Abstract
Mortality reductions
in developing countries are faster at relatively
low levels of economic development than those
achieved in developed countries. In this context,
this paper is an attempt to briefly describe the
major factors responsible for rapid mortality
reductions in developing countries compared to
developed countries focusing on their differences
in the speed, context and process of mortality
transition. This paper provides evidence from
three developing countries in favour of complex
mechanisms of rapid decline in mortality in developing
countries. Available literature suggests that
mortality reductions in developed countries took
place phase by phase, mainly related with economic
development, public health measures and improvement
of medical sciences, while it is a complex process
in developing countries and mainly related to
public health programs, target-oriented preventive
measures and broader socio-cultural, political
factors of economic development.
|
- - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - -
INTRODUCTION
Mortality
has historically played an important role in determining
the growth of population in all societies. Mortality
rates have started to decline in many countries of the
developed world just after the Industrial Revolution(1).
It, more specifically, has started to decline since
the 18th century along with rapid increase in life expectancy
throughout the world and especially in developed countries.
There is a remarkable difference regarding the rate
of mortality reductions between developed and developing
countries. The rate of mortality decline in developed
countries was almost linear and the average annual mortality
improvement rate was lower during the period 1950s-1970s
than that observed in developing countries(2).
The magnitude and demographic character of this improvement
have been illustrated in a number of documents and the
rate of mortality reductions in developing countries
exceeds that ever observed in developed countries(3&4).
However, only a few detailed case studies have attempted
to identify factors determining mortality declines in
selected developed and developing countries. This paper
tends to explain changes in mortality in developing
countries by considering levels, patterns, trends and
some selected social and economic factors of mortality.
METHODOLOGY
The study is based on published
articles and reports which summarize the results of
different research projects in the areas of mortality,
health, life expectancy and diseases that lead to mortality.
Evidence from three developing countries, Sri Lanka,
Cuba and Bangladesh, has been purposively used to demonstrate
the possible direct and indirect causes of rapid mortality
reductions in developing counties, as these three countries
have experienced rapid decline in mortality without
having remarkable economic development.
Nature of mortality reductions
in developed and developing countries
Historically, many European countries experienced gradual
but steady achievement regarding the increase in life
expectancy at birth and the decrease in mortality rates
during the 18th century. But mortality improvements
in developed countries as a whole have been slow since
1950 and the major improvement has come from the reductions
of infectious diseases among infants and children(5).
Gwatkin(6) identified three
phases of mortality reduction throughout the world of
which the first and the second waves were mostly observed
in several parts of European countries and the third
was in developing countries. The range of average annual
increment in life expectancy at birth, 0.20 to 0.40
years, during the first phase was lower than the average
annual increment, more than one year, of the second
and third phases(7). A similar
transition took place in almost all developed countries
with moderate differences in timing(8).
However, the decline of mortality
in developing countries as a whole happened after World
War II (9,10,11). Fragmentary
records indicate that life expectancy at birth during
1935-39 was 30 years in Asia and Africa and about 40
years in Latin America. By the late 1960s, the respective
levels were in the order of 50, 43 and 60 years(12).
Almost in every developing country, life expectancy
at birth gained more than one year annually during the
first couple of decades and around two years in the
1940s and early 1950s(13)
which was at least three times higher than those achieved
in West Europe during its mortality transition.
Factors
related to mortality reductions in developed and developing
countries
The above discussion reveals
that mortality reductions in developing countries were
faster than those achieved in developed countries. However,
there is little consensus about the causes of the greater
rate of mortality decline in developing countries. There
is still a debate on whether the mortality decline and
improvement in life expectancy has been principally
a by-product of socio-economic development as reflected
in people's access to the basic needs or whether it
is produced by social policy measures or it is the outcome
of technological changes in health and its impact on
other sectors(14).
The mortality reductions in developed countries are
related to socio-economic development, agricultural
and industrial revolutions, mortality reductions from
war and successful application of development in public
health measures and medical sciences(15,16,17
). Cutler, Deaton and Lleras-Muney(18)
explained three phases of mortality transition. The
first phase, started in the middle of the 18th century
and ended in the middle of the 19th century. Economic
growth, improved nutrition and public health measures
played a major role in health while in the second phase,
which started at the end of the 19th century and ended
in the 20th century, mainly public health measures played
the principal role. In the final phase, from the 1930s
onwards, medical science improvement and personal interventions
have played a very important role in health.
McKeown(19) focused on rising
standards of living and availability of food for the
decline of infectious diseases and mortality reduction
in England and Wales. He argued that better living standards
led to mortality reduction; as better living led to
better nutrition thus lower exposure to infections and
higher capacity to resist diseases. Mortality reductions
in England and Wales during the nineteenth century were
associated with a rising living standard, the changes
in hygienic practices, and a favourable relationship
between infectious agents and host humans(20).
But in the developing countries mortality reductions
during and after the post war period was faster because
of technological advancement for infectious diseases.
These technologies were already available in many developing
countries and in some cases were highly subsidized and
sometimes directly implemented by international organizations,
which are known as vertical programs. The development
and mass application of various measures, like piped
water, immunization coverage and use of antibiotics,
had taken many years in the West but were introduced
to the developing countries relatively within a short
period of time(21,22,23
). Moreover, the modern health and public health measures
were introduced in developing countries when mortality
levels were much higher than in the developed countries(24).
The success of decline in mortality in Western societies
came gradually as a result of improved diet, sanitation
and medical discoveries. The mortality decline was gradual,
as invention and application of death control mechanisms
took a long time(25). However,
most of the discoveries demonstrated that widespread
leading causes of deaths, like malaria, cholera, syphilis,
diarrhoea, typhoid, can be controlled with a relatively
low cost and within a short time. Davis further argued
that rapid decline in mortality in developing countries
happened due to international disease control inventions
rather than economic development.
The process and causes of death reflects the process
of demographic or epidemiological transition. The term
epidemiological transition explains the process of change
in leading causes of death that took place as mortality
reduction progressed from infectious diseases to chronic
non-transmitting diseases(26,27).
Globally, around 60% of total decline in death rate
was achieved because of the decline in mortality from
infectious diseases(28).
It indicates that infectious diseases played a major
role in mortality reductions in the past two centuries.
In Western societies, socio-economic factors were the
primary determinants of mortality transition while public
health measures played a crucial role for rapid mortality
reduction in developing countries(29,30,31).
Preston(32) considered diseases
as liable factors for mortality reductions and argued
that preventive measures, like immunization, water supply,
and sanitation, that took place in many developing countries
during the second half of the twentieth century, were
the most effective in determining mortality reductions
in developing countries. Additionally, the impact of
economic development was observed only for influenza/pneumonia/bronchitis
while improvements for infectious and diarrheal diseases
came through improved water and sanitation programs.
Moreover, structural factors - income, nutrition and
health infrastructure, accounted for around 50% increase
in life expectancy in developing countries between 1930s
and 1960s(33). The result
seems similar to Fogel's 1994 explanation in which nutrition
was considered as a key determinant of mortality reduction
in developing countries(34).
Caldwell(35) discussed 'breakthrough
periods' of mortality reductions in developing countries
with several dimensions of economic, social or public
health changes. His analysis shows that mortality reductions
in Kerala (1956-1966), Sri Lanka (1946-1953) and Costa
Rica (1970-1980) were outstanding in their socio-political
atmosphere and in their successful efforts in the areas
of education, health service and nutrition. The role
of cultural factors such as female autonomy, political
willingness and intrinsic value of education, is most
important in accepting and adopting new health inputs
and technologies.
Another line of argument for differential pace of mortality
reduction is the increase in the natural biological
limit of life expectancy that was achieved earlier in
many developed countries. But in developing countries
there is still scope to make the rate faster by taking
various measures. This is perhaps related to people's
psycho-social attitudes and a certain point in time
which stimulates people in developing countries to change
their socio-cultural practices and use available health
services. For example, during 1965-1985, life expectancy
at birth increased only around two years in developed
countries and around eight and half years in developing
countries(36). The process
of demographic/epidemiological transition in developed
countries strengthens the belief that humans can control
and modify their environment and destinies(37,38,39).
Moreover, the higher velocity and frequency of famine,
and fatalistic war in developed countries may also be
responsible for mortality variations between developed
and developing countries. For example, during World
War 2, the Soviet Union and Europe may have sustained
losses of 30-35 people per thousand(40).
Similarly, the recorded number of localized famines,
were more than 450, in Western Europe from 1000-1855(41)
indicates the issue of food scarcity as an important
factor for slow mortality reductions in developed countries.
Mortality reductions in developing
countries: Country-specific examples
Case Study: Sri Lanka
The historical decline of mortality in Sri Lanka has
been cited frequently as an example in demography. The
mortality change in Sri Lanka shows that the crude death
rate fell from around 30/1000 to 18/1000 live births
during 1920 and 1946(42).
S A Meegama claims that mortality reduction of this
period was associated with reduction of deaths from
under-nutrition and starvation as well as from water
contamination and sanitary related programs. The postulation
of Frederiksen(43) complements
these results. Frederiksen further argued that in Sri
Lanka factors unrelated to living standards were particularly
important in malaria endemic regions.
In Sri Lanka mortality reduction took place in three
phases(44). The first phase,
started in the second half of the nineteenth century,
with food availability, greater control of famine and
cholera playing a vital role in mortality reductions
while in the second phase, which started before World
War 2 (WW2), public health measures, like water and
sanitation, maternity and child welfare services and
rising standards of living were vital. In the third
phase, starting after World War 2, malaria eradication
programs, use of antibiotics and improved public health
infrastructure were crucial for mortality reductions.
However, many experts argued
that the malaria control program, which started in 1945
in Sri Lanka, was the major factor for mortality reductions
in Sri Lanka(45,46,47,48).
Findings of Newman(49) showed
that the DDT campaign alone explained around 42% of
reductions of mortality during 1936-1945 and 1946-1960
with observed national CDR falling to around 20.4/1000
to 11.7/1000 during that time. The role of public health,
sanitation and personal hygiene was observed at the
time of the successful campaign against mortality related
to diarrhoea, ARI, and hookworm disease in 1910. Other
important measures, such as DDT spraying to eradicate
malaria, use of penicillin and sulpha drugs, were added
to reduce mortality after the WW2(50,51).
Nevertheless, the role of DDT-spraying on mortality
in Sri Lanka is unsatisfactory because Sri Lanka's mortality
started to decline in the early 1940s and the malaria
control program was initially implemented in limited
geographical areas and its impact on mortality was overestimated
(52,53,54). Malaria eradication
campaign was probably responsible for around 16% of
mortality reductions during that time while other public
health improvements have played some role in mortality
reductions(55). Equally,
Frederiksen(56) argues that
around 50% mortality reductions in Sri Lanka took place
in non-malaria zones at the time of using DDT insecticides.
Case Study: Cuba
The historical mortality reduction in Cuba could be
the example of mortality transition of other colonial
developing countries, as Cuba was a colony of the US
for four years between 1898 and 1902. The role of colonization
is observed in improving health infrastructure of many
developing countries like Cuba and Sri Lanka. The mortality
transition of Cuba is almost identical with that of
the US and seems also to be similar to those of England
and Wales. Many factors responsible for mortality reductions
during this period were independent of socio-economic
development but dependent on the Colonial Emperor(57).
In Cuba, US occupation instituted a series of sanitary
reforms, leading to a virtual elimination of yellow
fever and reductions in mortality from malaria, tuberculosis
and infectious and parasitic diseases.
Improvements in economic conditions, nutrition and antibiotics
were initially responsible for mortality reductions
from tuberculosis (more than half of the overall decline)
between 1901 and 1953 while other infectious and parasitic
diseases were reduced due to sanitary and public health
measures(58). Other diseases
related to mortality such as diphtheria was reduced
by the use of antitoxin; malaria because of malaria
protection campaigns; and diarrhoea, gastritis and enteritis
owing to widespread sanitary reforms and improved water
supply. Beside these, other public health efforts and
increases in literacy played an important role for infant
and maternal care. However, the use of modern drugs
was mainly responsible for mortality reductions related
to influenza/pneumonia/bronchitis. The argument of McGuire
and Frankel(59) recognises
these findings with highlighting the role of access
to public health care in Havana.
Case Study: Bangladesh
The mortality transition in Bangladesh recognizes the
importance of broader socio-cultural, economic and political
factors and of target oriented vertical programs which
Caldwell(60) generalized
as "breakthrough" to low mortality. Menken
and Phillips(61) argues
that increasing parental education, economic ownership
and household dwelling and family planning programs
played an important role for mortality reductions in
Bangladesh during 1967-1987. D'Souza(62)
argues that socio-economic and cultural factors have
played a vital role in Bangladesh in reducing infant
and child mortality, as these factors led to increasing
the probability of using modern health care services.
Educated mothers are likely to be aware of their own
health as well as of their children's and they have
more possibility to practice and use available and affordable
preventive and curative health services.
Moreover, familiarization with Western values and institutions
as a result of education reduces the degree of resistance
in seeking medical care or using modern health facilities(63,64).
Thus, mass education and modernization are crucial in
changing people's attitudes towards different vertical
programs. For example, the immunization program in Bangladesh
was initiated in 1979 but within a few decades nearly
82% children are now fully immunized(65,66).
The role of family planning, tetanus vaccination and
oral rehydration saline (ORS) has been discussed in
Chen et al.(67) to explain
mortality reductions in Matlab Thana, Bangladesh, during
1966-1981. The result shows that tetanus vaccine given
to pregnant women reduced 68% mortality for new born
babies which was equivalent to around 26% of total deaths.
Family planning program was responsible for 25% (half
of the decline in that period) mortality reductions
and ORS for another 9%. Another study(68)
conducted in the same area between 1983 and 1987 shows
that around 50% of neonatal deaths occurred from tetanus
and another 20% from acute respiratory infection. Nevertheless,
some critiques argue that vertical programs have done
little for the development of domestic healthcare system
despite their successful implementation(69,70,71).
CONCLUSION
The historical experiences of mortality reduction in
developing countries with different context and space,
indicate that it is very difficult to isolate the specific
role of each different determinant. Thus the postulation
of the precise nature of the causal relationships regarding
mortality reductions in developing countries may tend
to be an oversimplification of a complex process of
interaction of multiple factors. The framework of Mosley
and Chen(72) for child survival
supports this finding. Mortality reductions in developing
countries require multifactor explanation rather than
a cause-specific single factor approach.
Overall, the evidence supports that the pace of mortality
reductions in developing countries is mainly related
to public health programs, target-oriented preventive
measures and broader socio-cultural, political factors.
It also indicates that the relationship between the
decline in mortality and economic development is weaker
but not pointless. The mechanisms of mortality reductions
between developed and developing countries during the
last two centuries were almost similar but they differ
in the intensity with which they affected the trend
of declining mortality at a given point of time.
REFERENCES
Basu, AM 1989, 'Household
influences on child mortality: Evidence from historical
and recent mortality trends' in JC Caldwell and G Santow
(eds), Selected Readings in the Cultural, Social and
Behavioural Determinants of Health, Health Transition
Centre, ANU, Canberra.
BDHS (Bangladesh Demographic
and Health Survey) 2007, National Institute of Population
Research and Training (NIPORT), Mitra and Associates,
and Macro International, 2009. Dhaka, Bangladesh and
Calverton, Maryland, USA.
Caldwell, JC 1986, 'Routes to
low mortality in poor countries', Population and Development
Review, vol. 12, no. 2, pp. 171-220.
Caldwell, JC 1989, 'Mass education
as determinant of mortality', in JC Caldwell and G Santow
(eds) Selected Readings in the Cultural, Social and
Behavioural Determinants of Health, Health Transition
Centre, ANU, Canberra.
Chen, LC, Rahman, M, D'Souza,
S, Chacraborty, J and Sarder, AM 1983, 'Mortality impact
of an MCH-FP program in Matlab, Bangladesh', Studies
in Family Planning, vol. 14, no. 8/9, pp. 199-209.
Cutler, D, Deaton, A and Lleras-Muney,
A 2006, 'The determinants of mortality' The Journal
of Economic Perspectives, vol. 20, no. 3, pp. 97-120.
D'Souza, A 1986, 'Mortality
structure in Matlab (Bangladesh) and the effect of selected
health interventions', in United Nations Publication,
Determinants of Mortality Change and Differentials in
Developing Countries: The Five-Country Case Study Project,
Department of International Economic and Social Affairs,
Population Studies, no. 94, STIESA/SER.A/94, Sales No.
E.85.XIII.4
Davis, K 1956, 'The unpredicted
pattern of population change', The ANNALS of the American
Academy of Political and Social Science, vol. 305, pp.
53-59.
Diaz-Briquets, S 1981, 'Determinants
of mortality transition in developing countries before
and after the Second World War: some evidence from Cuba',
Population Studies, vol. 35, no. 3, pp. 399-411.
Frederiksen, H 1960, 'Malaria
control and population pressure in Ceylon', Public Health
Reports, vol. 75, no. 10, pp. 865-868.
Frederiksen, H 1961, 'Determinants
and consequences of mortality trends in Ceylon', Public
Health Reports, vol. 76, no. 8, pp.659-664.
Frederiksen, H 1970, 'Malaria
eradication and the fall of mortality: A note', Population
Studies, vol. 24, no. 1, pp. 111-113.
Gray, RH 1974, 'The decline
of mortality in Ceylon and the demographic effects of
malaria', Population Studies, vol. 28, no. 2, pp. 205-229.
Gwatkin, DR 1980, 'Indications
of change in developing countries' mortality trends:
the end of an era?' Population Studies and Development
Review, vol. 6, no. 4, pp. 615-44.
Jamil, K., Bhuiya, A., Streatfield,
K. and Chakrabarty, N., 1999, 'The immunization programme
in Bangladesh: impressive gains in coverage, but gaps
remain', Health Policy and Planning, vol, 14, no. 1,
pp. 49-58.
Kirk, D 1996, 'Demographic transition
theory', Population Studies, vol. 50, no. 3, pp. 361-387.
Kitagawa, EM 1977, 'On mortality',
Demography, vol. 14, no. 4, pp. 381-389.
Koenig, MA, Fauveau, V, and
Wojtyniak, B, 1991, 'Mortality reductions from health
interventions: the case of immunization in Bangladesh',
Population and Development Review, vol. 17, no. 1, pp.
87-104.
Konradsen, F, Amerasinghe, P,
Derhoek, WV, Amerasinghe, F, Perera, D and Piyaratne,
M 2003, 'Strong association between house characteristics
and malaria vectors in Sri Lanka', American Journal
of Tropical Medicine and Hygiene, vol. 68, no.2, pp.177-181.
Langford, CM 1996, 'Reasons
for the decline in mortality in Sri Lanka immediately
after the Second World War: a re-examination of the
evidence', Health Transition Review, vol. 6, pp. 3-23.
McGuire, JW and Frankel, LB
2005, 'Mortality decline in Cuba, 1900-1959: patterns,
trends, comparisons, and causes', Latin America Research
Review, vol. 4, no. 2, pp. 83-116.
McKeown, T 1976, 'Diseases which
declined' in The Modern Rise of Population, Edward Arnold,
London, pp. 44-72.
McKeown, T and Record, RG, 1962
'Reasons for the decline of mortality in England and
Wales during the Nineteenth Century', Population Studies,
vol. 16, no. 2 , pp. 94-122.
Meegama, SA 1967, 'Malaria eradication
and its effect on mortality levels', Population Studies,
vol. 21, no. 3, pp. 207-237.
Meegama, SA 1986, 'The mortality
transition in Sri Lanka', in United Nations Publication,
Determinants of Mortality Change and Differentials in
Developing Countries: The Five-Country Case Study Project,
Department of International Economic and Social Affairs,
Population Studies, no. 94, STIESA/SER.A/94, Sales No.
E.85.XIII.4.
Menken, J and Phillips, JF 1990,
'Population change in a rural area of Bangladesh, 1967-87',
The ANNALS of the American Academy of Political and
Social Science, vol. 510, no. 1, 87-101.
Mosley, WH and Chen, LC 1984,
'An analytical framework for the study of child survival
in developing countries', Population and Development
Review, vol. 10, pp. 25-45.
Newman, P 1977, 'Malaria and
Mortality', Journal of the American Statistical Association,
vol. 72, no. 358, pp. 257- 263.
Omran, AR 1971, 'The epidemiologic
transition: A theory of the epidemiology of population
change', The Milbank Memorial Fund Quarterly, vol. 49,
no. 4, pp. 509-38.
Preston, SH 1980, 'Causes and
consequences of mortality declines in the less developed
countries during the twentieth century' in R Easterlin
(eds), Population and Economic Change in Developing
Countries, University of Chicago Press, Chicago.
Soares, RR 2007, 'On the determinants
of mortality in the developing world' Population and
Development Review, vol. 33, no. 2, pp. 247-287.
UN (United Nations) 1953, The
Determinants and Consequences of Population Trends-A
Summary of the Findings on the Relationships between
Population Changes and Economic and Social Conditions,
ST/SOA/SER.A/17, United Nations, New York.
UN (United Nations) 1973, The
Determinants and Consequences of Population Growth-New
Summary of Findings on Interaction of Demographic, Economic
and Social Factors, ST/SOA/SER.A/50, United Nations,
New York.
UN (United Nations) 1982,
'Levels and Trends of Mortality since 1950' A joint
study by the United Nations and the World Health Organization,
Department of International Economic and Social Affairs,
ST/ESA/SER.A/74, Sales No. E.81.XIII.3
- - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - -
|
