Surgery and Healing in the Developing World - Dartmouth-Hitchcock

CHAPTER 1
CHAPTER 28
Population Dynamics of Surgical Tropical
Diseases
Ricardo Cohen, Frederico Aun, Glenn W. Geelhoed and Eric L. Sarin
In the tropical areas of the world live the largest human populations with the
highest growth rates and the youngest population pyramids. These facts have immediate
implications for the incidence of disease and the needs for medical and surgical
services. Because of the skewed age curve of the population (many tropical countries
have the median population age represented by teenagers!) relative to temperate
populations, which have a proportionally larger burden of older population and
may even have zero population growth, disease incidence will be remarkably different.
For example, the latter populations will have a larger burden of degenerative
and malignant diseases of cardiovascular, CNS and GI and musculoskeletal abnormalities
that are acquired later in life, whereas the tropical populations will have a
higher proportion of congenital, communicable and traumatic illnesses largely on
the basis of the age distribution of the respective populations. Venereal diseases would
not be expected to be a major concern in a geriatric population, whereas the teeming
populations of urban youth in many tropical port cities are a virtual hothouse
for such epidemics.
Disease Prevalence Influenced by the Skewed Population
Pyramid Some as Cause, Some as Effect
Communicable diseases include those considered tropical diseases by their distribution,
which are to some degree cause, and even to a greater degree effect of the
population dynamics. Malaria is a disease with a very high incidence in most tropical
areas, with a morbidity and mortality differential that is directly attributable to
this age differential. The death rate is highest among the young who may not have
yet acquired a relative immunity to the lethal forms of the disease from frequent
exposure to the morbid illness that may be partially protective for forms such as
cerebral malaria of the falciparum parasite. The high wastage of the under-five population
has fueled an immemorial desire for high fertility and a heritage of large
families, based in the only social security that can be considered by many residents
of weak or failed states or warring communities.
Trauma is a great common denominator between the developed and developing
world. Mechanized transport may be faster in the developed world, but is surely
more hazardous in the developing world, and the environmental risks of farming,
forestry and the unfortunate high risk of violence from crime and warfare in unstable
states makes trauma cases a surgical staple in any tropical theatre list.
Given the population pyramid and the high fertility rates, another staple of operative
treatment that is often under-appreciated by some volunteers who have not
Surgery and Healing in the Developing World, edited by Glenn Geelhoed.