In the Report of the Principal Registrar of Deaths
in the Gold Coast for 1933 it was stated that during the
previous three years the proportion of deaths from pulmonary tuberculosis had far exceeded that of all other
killing diseases with the single exception of non- tuberculous affections of the respiratory tract.
This disease accounted for 9.9 per cent. of the total
deaths in 1931, 9.2 per cent. in 1932 and 10.5 per cent.
in 1933. Tuberculosis of the respiratory tract and consequently the most infective form of the disease was far
more common than any other type. In 1933 deaths from
pulmonary tuberculosis numbered 658 as compared with 47
from other forms.
In the Report of the Medical Department, Gold Coast,
for 1932 -33, the Director of Medical Services wrote that
the tuberculosis problem was one of the most important to
be faced. He attributed the high incidence of this disease to insanitary housing, overcrowding, a total ignorance of the rudimentary laws of hygiene and lack of
immunity. This lack of immunity associated with scanty
tuberculisation of the native races is stressed by Young'
in discussing the spread of tuberculosis among the African
population of Nigeria.
As resistance to a disease may be natural or acquired,
so lack of it may be due to inherent susceptibility or to
absence of opportunity to acquire immunity.
According to Opie, there is' no proof that the negro
race has any inherent susceptibility to tuberculosis, and
in another report, the same author writes: "There is
indeed very little convincing evidence for or against the
opinion that inherited susceptibility on the one hand, or
inherited resistance on the other, modifies the progress
of tuberculosis in human beings ".
Carter, on the other hand, has tried to show that
the black races have less innate resistance than the white.
He cites the results of sanitorium treatment to show that
tuberculosis undergoes improvement more frequently in
white people than in negroes, and he attaches particular
significance to the observation that Mulattoes are in this
respect intermediate between whites and blacks. He points
out that Mulattoes and blacks live under practically identical environmental conditions, and he concludes that the
Mulatto is more resistant because the White race has transmitted part of its inherited immunity to him.
Carter has not considered the other possibility that
the whites have by contact transmitted the disease to the
Mulatto, and that by reason of this, acquired resistance
may have been established. This possibility cannot be
Fishberg states that tuberculosis is inherently not
a racial problem and that one human race or ethnic group,
when first encountering the tubercle bacillus, is as
vulnerable to infection as another. It is only after
they have been exposed to infection for generations that
they acquire a certain degree of resistance which causes
milder clinical forms of the disease than are found in
races which are virgin soil to the bacilli.
It would appear, therefore, that any want of immunity on the part of West African natives is due rather to
lack of opportunity to develop resistance than to any
hereditary or racial predisposition to the disease. This
view is supported by Griffith6, who says that races previously free from tuberculosis are much more susceptible
to the disease than those who have long been exposed to
infection. He attributes the greater resistance of infected communities either to a weeding out of the more
susceptible human beings, the resistant individuals surviving, or to an acquired immunity produced by slight
infections which have been overcome.
As acquired immunity depends on exposure to infection it would seem necessary to know the incidence of
tuberculous infection before one can consider the degree
of resistance to tuberculosis which a given population
may have developed.
A comparison of the infection rate with the mortality
or morbidity rates would then give a measure of the
acquired resistance of the population in question. A
high infection rate associated with low mortälity or
morbidity rates would suggest a considerable degree of resistance; the reverse condition would point to a low
It was because the author was unable to find any
record of the incidence of tuberculous infection among
the native inhabitants of the Gold Coast that the present investigation was begun.