leprosy is not easily transmissible, it is hard to shake off the stigma
associated with the condition.
Leprosy has been eradicated in 116 out of
122 countries where it is endemic. The global
prevalence of leprosy has been reduced by
more than 90% since 1985, with more than
14.5 million people cured of the condition.
However, there are pockets of the condition in
Africa, Asia and South America.
A condition which has been documented
since pre-biblical times, leprosy is caused by
the bacteria, mycobacterium leprae. The exact
mode of transmission is not known. Although
it is a communicable disease, one can only get
infected through prolonged close contact. It is
believed that the methods of transmission are
through skin-to-skin contact and droplets
from the mouth and nose. Humans are the
only known reservoir of infection, although an
organism that is indistinguishable from
mycobacterium leprae has been found in wild
armadillos in the United States.
Leprosy affects both sexes, regardless of age.
Its progress is slow and the average incubation
period is between three and eight years.
Symptoms can take as long as 20 years to
appear. Patients can lead normal lives. If the
disease is detected early and treated, it will
not result in disabilities. If untreated, it may
result in progressive damage to the skin,
nerves, eyes and limbs.
Leprosy is described clinically as tuberculoid
and lepromatous, with a large borderline
group between the first two groups. It affects
the skin and nerves, mainly. The affected skin
has a patch or patches, with definite loss of
sensation. They can appear anywhere and can
be flat or raised, pale, red or copper-coloured.
The patches cannot feel touch, heat or pain,
and does not itch. Other signs include skin-coloured or reddish nodules or smooth, shiny,
diffuse thickening of the skin without loss of
In general, leprosy should not be diagnosed
without a definite loss of sensation. Leprosy is
categorised into paucibacillary and multibacillary types, depending on the
number of patches. There are one to five patches in the former,
and more than five in the latter.
There may be ulcerations on the hands and
feet, weakness and the wasting of muscles and
a claw foot or a foot drop. The nerves may be
enlarged, palpable or visible, especially those
near the affected skin. The eyes and the testes
may be involved, with infection and glaucoma
in the former, and sterility and enlarged
breasts (gynaecomastia) in the latter.
Mycobacterium leprae is an acid fast, rod-like organism (bacilli). It cannot be cultured in
a laboratory dish. However, it has been cultured using mice and the nine-banded
armadillo. DNA technology has made it possible to clone genes of the bacteria.
Skin and nasal smears can be checked for
acid fast bacilli by using stains. Skin biopsies
are useful for the diagnosis and classification
of leprosy. The biopsy findings vary depending
on the type of leprosy. Granulomas are usual.
The nerves may be visible or destroyed. The
bacilli may be abundant, few or absent.
There may be different abnormalities
detected in nerve conduction studies carried
out when the nerves are affected. Nerve biopsies may reveal abnormalities. Sometimes, it is
the only method of making a diagnosis.
The World Health Organisation recommends a multi-drug therapy (MDT), comprising the use of dapsone, rifampicin and clofazimine. The drug regimen kills the bacteria and
cures the patient. The MDT is very effective.
Those with paucibacillary leprosy are usually
cured within six months, while those with
multibacillary leprosy are cured within 12
months. Patients are no longer infectious after
completing the first dose of MDT. There is virtually no recurrence after treatment has been
completed. It is safe to use MDT in pregnant
women and patients with tuberculosis or HIV
It is important for patients to understand
that the full course of medication must be
completed. If treatment is interrupted, it has
to be started all over again. All patients under-
going treatment can lead normal lives.
The drugs may cause the urine to be red
and/or the skin may darken. This should not
be of concern, as it will return to normal upon
completion of treatment. However, immediate
medical attention should be sought if there are
any problems, e.g. fever, pain, muscle weak-
ness, tiredness, swollen hands and feet, skin
changes like nodules, and loss of sensation.
These are not side effects of MDT but the
body's response to leprosy.
Leprosy sufferers who have loss of sensation in the hands and feet may
injure themselves without noticing it. Subsequently, the wounds may get
infected and deformities may result. Family members and those who have close
contact with a leprosy sufferer have to be examined if they have a skin
abnormality. The earlier a diagnosis is made, the sooner treatment can
commence. This will prevent transmission of the condition, and also prevent
complications and deformities from developing.