Human bacterial diseases Essay Example

function of the sweat and sebaceous glands. This causes a drying of the skin and consequent cracking, exposing the sufferer to secondary infection. Leprosy is not a curse from the gods or divine punishment for some sins committed in the past.

Leprosy is a disease like any other disease and it is TOTALLY CURABLE. Another myth that still prevails, even in "educated" societies, is that the disease causes flesh to rot and fingers and toes to "drop off". Nothing could be further from the truth. Tragically, limbs that are damaged, because the victim cannot feel pain, sometimes have to be amputated but, we can now detect the disease before the patient is conscious of any loss of sensation.

Even if the patient has experienced some measure of deformity, we are able, through chemotherapy, physiotherapy, and reconstructive surgery, to correct many of the disabilities. Ideally, we should detect the disease before there is any need for physiotherapy or reconstructive surgery.

In such cases, where only chemotherapy is required, treatment is very cheap. On average, it costs only $15.00 per month to provide drugs and services to cure one patient of leprosy. What other disease, of such horrendous magnitude, can be treated for a mere $180.00 per year? However, progress is being made. In 1951, there were 15 million leprosy sufferers worldwide.

Today, the W.H.O. (World Health Organization) estimates that 6 million people remain to be treated, either through chemotherapy, or physiotherapy/surgery, or both. It should also be remembered that even though many patients are being cured, thousands still suffer because of deformity and stigma. They may have become bacteriologically "negative" but a prejudiced, uneducated, and ill-informed society may

still reject them because of these disabilities that they had absolutely no control over.

We may be able to kill off their germs, but we cannot restore their sightless eyes or amputated limbs.

Incidentally, many of their insensitive, ulcerated fingers and toes are eaten off, not by the leprosy germ, but by rats and other animals. For this reason, early diagnosis, along with early treatment and health education, are of vital importance. Historical Although leprosy is widely regarded as one of the oldest diseases known to man, it has not accurately been described and distinguished from other diseases with similar appearances until 1847. Historically, the first full accounts of various forms of leprosy are from India (600 B.C.). They described different kinds of skin lesion as well as peripheral nerve damage and offered a unifying concept to embrace all these manifestations. The next records of leprosy are slightly later dated from China. In the Western world, no identifiable clinical descriptions of leprosy are known prior to the third century B.

C., when the Lepromatous type came to be known to the physicians of Alexandria under the name elephantiasis. Some scholars have suggested that Alexandria obtained leprosy when the troops of Alexander the Great returned from the Indian campaign in 327-326 B.C.

Italy is said to have acquired leprosy from Pompey's soldiers returning from Egypt (62 B.C.). The exact meaning of the word leprosy still varies widely in the Old and New Testaments. In Hebrew, tsaraath, scaly blemishes on skin, cloth, leather, or the walls of houses are associated with ritual defilement.

But still, nowhere is their mention of the characteristic signs of leprosy as we know

them today, even with all the confusing descriptions mentioned. In the Old Testament, references show that it may possibly have been to rue leprosy, and the lepra of the New Testament probably included the disease. Not until 1873, did Armauer Hansen of Norway, recognize that the disease was caused by M. Leprae. This new knowledge subsequently led to improved staining methods and better microscopes making possible a wealth of pathological studies. But until the 1940s, early diagnosis and isolation were the only possible methods for the control of HD.

By 1950, Dapsone became the standard treatment for HD, and the rapid improvement in patients led to hopes of the elimination of HD.

The number of leprosy sufferers in the world is not known with certainty. Estimates have been made by governments and other private organizations, but some countries are reluctant to acknowledge the seriousness of their leprosy problem or even that they have a problem. They may also lack reliable and complete statistics for leprosy and other endemic diseases. The majority of these cases are found in Africa, India, South America, and Southeast Asia.

There are about 4,000 cases in the United States, but about three-fourths of these patients have contracted the disease in other countries and brought it to the U.S. California, Florida, Louisiana, and Texas are the states where the disease is found most commonly. Today the spread of leprosy is subject to movements of population, for instance of Southerners in the U.S.

northwards, of Mexican farmhands seasonally to California, of Puerto Ricans to New York City. Leprosy may be introduced by immigrants into countries that have been free of original cases for many years;

such as southern Europeans into France, Switzerland, and Belgium, by North Africans into France. In these countries, however, the imported disease has not re-established itself, and secondary cases among contacts are extremely rare.

Types of Leprosy

There are two main types of leprosy.

Lepromatous, which affects mainly the skin, and Tuberculoid, mainly comprising of the nerves. The two other forms, Borderline and Indeterminate, eventually grow into one of the two principle types. Lepromatous Type This type is found in patients without an immune resistance to the Mycobacterium leprae organism and is the widespread, anergic form of the disease. The organisms can always be found in enormous numbers in the deep layers of the affected skin. The disease then spreads up the nerves but does not adhere to them as in the Tuberculoid form.

It very often spreads to the skin of the face, where it causes thickening and corrugation of the skin and a typical leonine appearance. Soft nodules appear on the ears, nose, and cheeks and sometimes break down into discharging sores. The nose often is teeming with bacilli, and this sometimes leads to the destruction of the septum of the nose and the palate. There are many varieties of Lepromatous leprosy: Macular, Diffuse, Infiltrated, Nodular, and Polyneuritic.

The Lepromatous skin lesions involve cooler parts of the body surface and are characterized by massive collections of macrophages containing large numbers of acid-fast bacilli.

Tuberculoid Type

This is the localized form of the disease and is due to a combination of bacterial proliferation and the immunologic responses of the host bacilli. The skin lesions are characterized as single or multiple; macular or

raised; either indolent or spread centrifugally with some rapidity, and show a variable loss of pigmentation, sweating and tactile sensitivity. These skin lesions consist of one or, at most, a few well-circumscribed skin lesions with profound anesthesia. Due to the body's immune system, which responds more intensely to the presence of leprosy bacilli, this form of the disease is the most resistant. The body immune system also contains or localizes the disease to either a skin patch or a nerve trunk. The patient is unable to feel pain and minor injuries pass unnoticed.

Large eroding ulcers can form, causing loss of fingers and toes; sometimes the condition of the limb is so bad that amputation is necessary.

Indeterminate Type

This form of the disease effects people who are unable to resist infection of M. Leprae. The first sign of the disease is one or a few of hypopigmented skin macules with little sensory loss confined to the lesion. The development of these lesions can take anywhere from two to four years.

However, due to its variable course, in three-fourths of all patients, the disease heals spontaneously and in some cases, remains Indeterminate and eventually progresses to one of the forms of Tuberculoid or Lepromatous leprosy. Borderline Type As the name suggests, it includes those types of disease between Lepromatous and Tuberculoid leprosy. When a patient has this form of the disease they can go either two ways: Upgrading, which is when the patient develops more clinical, bacteriological, and histopathologic features of the Tuberculoid type. Downgrading, which is when the patient develops more features of the Lepromatous type. Borderline Tuberculoid leprosy (BT) resembles Tuberculoid disease except

that the number of skin lesions is usually greater, the edges of the skin lesions are less well defined, there is a tendency for satellite lesions to develop near the edges of the larger lesions, and individual lesion tend to be larger.

BT tends to damage peripheral nerves more widespread and severe than in TT.

Borderline Lepromatous leprosy (BL) resembles Lepromatous disease except that at least some of the skin lesions are selectively anesthetic and show varying degrees of distinctness in their borders. BL can develop (upgrade) from Indeterminate leprosy or by downgrading from BT. In Borderline leprosy (BB), the skin lesions are few to numerous in number, red or brown in color, rounded or oval in shape. The lesions are infiltrated throughout or with a central clear area or areas producing a punched-out appearance. Classification The method of classifying leprosy has been around for some time now.

The method was established in Madrid at the sixth International Congress of Leprosy in 1953. It was agreed that the basic criteria of classification should be clinical, depending on the examination of smears from skin lesions and nasal mucosa.

The congress also agreed that there should be two distinct forms of leprosy, Lepromatous and Tuberculoid. These two would be the poles of the immunological spectrum.

This form of classification did present some problems though, the International Classification System was much too complicated for the use of Indian leprologists. The Indian leprologists thought that the classification should be simple enough for use by field workers, but advanced enough for research done by workers with special investigative techniques.  This means that the LL and BL forms are Multibacillary leprosies.