[Music]
[Narrator:] Africa lies strategically
between the Americas and Asia.
[Music, drum beating]
It is a vast continent
stretching from Egypt in the north
to the Cape of Good Hope in the south.
It is a continent of high mountains,
immense plain,
rolling grassland,
deep verdant forests,
burning deserts,
expansive lakes,
and great rivers.
A continent of tremendous natural resources.
Many of them not yet developed.
[Ominous music] It also is the home of 150 million people.
But it is haunted everywhere by the grim specter of disease,
which constantly saps the strength of these people.
Madhura foot,
leprosy,
Guinea worm,
anthrax,
smallpox,
tropical ulcer,
Keller Azhar,
and sleeping sickness.
Victims of sleeping sickness may fall asleep
at any time in any place even while eating.
In general their bodies are insensitive.
They are morose and out of touch with their surroundings.
This deadly disease is one of the most widespread in Africa,
especially in the equatorial areas.
So effective have been its inroads
that large areas where colonization was attempted
had to be abandoned by both settlers and the natives.
Sleeping sickness not only attacks man,
but it attacks and kills his domestic livestock as well.
Sleeping sickness is caused by a protozoan organism,
trypanosome, which may be found
in the cerebrospinal fluid, lymph, and blood
of infected animals and people.
There are different species of trypanosome.
In general there are about 20 microns long,
equipped with a flagella and undulating membrane
for locomotion.
Trypanosomes may be seen directly under the microscope
without staining.
Domestic animals and people are exposed
to the bite of that tsetse fly,
which carries and transmits trypanosome.
Part of the life cycle of the trypanosome
is spent in the vertebrate host,
another part in the digestive tract of the fly.
There are several species of the tsetse fly belonging
to the genus Glossina.
All species have the characteristic cleaver cell in the wing.
Tsetse flies produce living offspring.
In the course of her life, the females tsetse
produces up to 10 larvae.
The larvae grow in the female and emerge fully developed.
Immediately after birth, the larvae
burrows into the loose soil.
In a few hours, the pupa stage is reached
when the protective casing forms around the pupa.
The fly emerges from this pupa after five days to three weeks
depending on the species of fly.
Another characteristic of all species of the tsetse fly
is a long proboscis used for biting.
Only about one out of 100 flies are infected
even in the sleeping sickness areas,
but because of the mass of flies,
the danger is great.
The reservoir hosts of the disease
are the wild animals of Africa.
The fly bites the animals.
The trypanosome develops in the body of the fly
and is finally transmitted to other animals or to human beings.
There are two main types of humans sleeping sickness,
which eventually attack the central nervous system.
First, chronic West African.
Characteristic of the early phase of this type are swollen glands
in the posterior triangle of the neck.
Known as Winterbottom's sign.
And the other,
malignant Rhodesian.
Swollen submaxillary glands
are characteristic of the early stage of this type.
Mass health surveys are conducted in a three -month cycle
in order to segregate, control, and treat
human reservoirs of the disease.
Those natives who are suspected of infection
are isolated for treatment.
But this is Africa and although modern medicine
has reached most regions of the continent,
native superstitions still persist.
Often the medicine man must examine a patient
before examination and treatment by a doctor is permitted.
The medicine man is still practicing
and occupies an important position in most tribes.
However, modern medicine is diligently at work in the field
gaining ground on the old superstition.
Characteristic signs of moderately advanced sleeping sickness
are a positive Romberg,
swollen feet,
swollen face,
hand tremor.
The patella reflex increased in the moderately advanced stages
then lost in the late stages.
The peculiar swaying gait associated with the disease,
and the fluctuating fever,
which forms a definitive sawtooth curve.
Diagnosis of sleeping sickness may
be confirmed by examination of a sample of lymphatic fluid
taken from the cervical lymph nodes.
Prognosis of a given case is indicated
by the Sicard-Catilube test.
After the spinal fluid is taken,
it is placed in a graduated tube.
It is then heated over an open flame to boiling point.
Trichloroacetic acid is added to the spinal fluid,
and it is allowed to set for four hours
until a precipitate forms.
Measuring the amount of precipitate
makes possible a prognosis.
Other confirmatory diagnostic tests
are cell counts in the cerebrospinal fluid, globulin,
and protein and Pandy's test.
In the late stages of the disease,
the patient exhibits other manifestations
of involvement of the central nervous system.
Such as loss of consciousness, loss of speech,
inability to eat or drink, and weakness of muscles approaching
complete paralysis.
This patient died shortly after being photographed.
The brain microscopically shows a Meningoencephalitis
with inflammatory infiltrates in the paravascular
spaces of the pia-arachnoid and cerebral vessels.
The perivascular infiltrate consists mainly
of lymphocytes with scattered neuro-glial elements
and histiocytes.
The fight against sleeping sickness
is being pressed on two fronts, therapy and prevention.
The disease can be arrested in the early stages,
and the patient can be made non-infectious
by the use of chemotherapy.
In addition, many attempts have been made to prevent infection.
One has been the shooting of the wild game [Gunshots]
to reduce the numbers of the vertebrate hosts.
But this may destroy a national heritage
and an essential part of the meat supply the natives.
Native boys have been trained to catch the tsetse flies in nets.
A similar attempt has been made by use of the Harris trap.
But both measures are too primitive to be effective.
The tsetse lives and breathes in shady places,
therefore clearing the undergrowth
is widely used to control it.
Clearing the banks of streams eliminates
one of the breeding places of the fly.
Cleared roads are fairly free from flies
and safe for travelers.
Clearing around houses and villages
will protect the people who live there.
[Axe chopping] In some areas, wholesale clearing
of forests infested with the tsetse flies
has been undertaken on a rather large scale.
Used indiscriminately, this burning and cutting
down of forests can create new problems
of soil erosion and depletion of the water supply.
The most modern and without doubt the most effective measure
of controlling the fly is
through the use of insecticides in its breeding areas. [Pump air rushing]
At first, spraying by hand was tried
but proved cumbersome and slow.
It was discarded in favor of spraying by aircraft.
Suitable apparatus and fittings have now
been developed for equipping planes
for spraying insecticides.
The efficiency of this spraying can be demonstrated
by placing live tsetse flies in gauze cages
and setting them out in various positions in the woods.
[Airplane engine roar]
The insecticide is then sprayed over the area
by planes flying just above the treetops.
[Airplane engine roar]
[Footsteps]
After spraying, the cages are collected.
The results are extremely satisfactory, nearly 100 percent kill.
In low valleys which cannot be treated by aircraft,
smoke grenades blowing insecticides are used.
This method may be applicable in the equatorial forest belt.
Probably the most successful method is
[Airplane engine roar] a combination of the use of aircraft and this type of smoke grenade.
[Airplane engine roar]
In a test area where spraying was tried, an average of 600
flies a week were being caught in Harris traps
before spraying.
It was only possible to catch three a week after spraying.
Once man retreated before the attacks of sleeping sickness. [Airplane engine roar]
Today with the help of science,
he is advancing against the disease.
A good start has been made to win
the fight against sleeping sickness,
but much remains to be done.
The fight against the disease must
be continued on a broad front.
The knowledge of sanitation must be widely applied.
[Music fades in]
Through these means, sleeping sickness can be blotted out
and large areas of Africa can be reclaimed.
[Music continues]
Healthy domestic livestock can be raised and sustained.
[Music continues]
[Dramatic music]
And finally, the lives of a great number of people
can be enriched and immensely improved.
[Dramatic music continues]
[Music transition to uplifting theme]
[Music fades out]