Nasty Infectious Diseases You Want To Avoid - Leprosy
This is a chronic bacterial infection (also called Hansen's disease) that damages nerves in the skin, limbs, face, and mucous membranes. Untreated leprosy can lead to severe complications, which can include blindness and disfigurement, but leprosy can be cured with proper medication. Contrary to popular belief, it is not highly contagious. While the disease still carries a significant stigma, patient care has become integrated with routine health care. Anti-leprosy organizations have fought to repeal stigmatizing laws and practices; patients are no longer referred to as "lepers."
Although leprosy is one of the oldest diseases in human history, it was not until 1873 that Armauer Hansen first identified the bacilli under a microscope. Today there are about 20 million leprosy patients in 87 countries, primarily in Asia, Central and South America, and Africa, but probably fewer than 20 percent have access to treatment. India has the highest prevalence of leprosy, followed by Brazil. In the United States, there are more than 6,000 known cases. Most are found in California, Florida, Hawaii, Louisiana, New York, and Texas. There are about 200 new cases each year in the United States, and 12,000 new cases each week around the world. Approximately 16 percent of the new cases of leprosy are children.
History - Ancient religious traditions associated with leprosy continued to influence social policy well into the 20th century. Leprosy was first mentioned as a curse in Shinto prayers of 1250 B.C.; it was also mentioned in some Egyptian legends to explain the exodus of the Hebrews. For hundreds of years, those with leprosy were taken to a priest, not a doctor, and were found "guilty," not sick. These customs led to the forcible confinement of patients in "leprosaria" or leper colonies; their children, whether infected or not, were denied an education in community schools. In eighth-century France, leprosy was considered grounds for divorce, and the Roman empire enforced banishment. Some countries passed legislation providing for the compulsory sterilization of leprosy patients because of fears that the condition was hereditary. Others would not permit patients to handle the nation's currency. Others "steam treated" patients' letters before allowing them in the mail, and some countries did not allow patients to vote. In medieval Europe, leprosy patients had to carry a "clapper" to warn others that a person with leprosy was approaching. Even as late as 1913, state Senator G. E. Willett of Montana was forced to give up his seat after he was diagnosed with leprosy. Leprosy is erroneously associated with the Old Testament, where references to tsara'ath, a term that most closely translates to "leprosy," actually refers to a broad spectrum of problems that affected cloth, leather, linen, and house walls as well as humans. Most medical historians doubt that leprosy even existed among the Hebrews in Moses' time. Biblical scholars also have problems with the translation of the Greek term lepra partly because the Greeks had a specific term for leprosy. The Greek word lepra was most likely used to mean a variety of severe skin diseases. Greek medical writings later than the third century B.C. provide the earliest clinical references to modern leprosy. No mention of leprosy occurs in the New Testament after the Gospels.
Cause - Leprosy is caused by a rod-shaped bacterium, Mycobacterium leprae, that is spread in droplets of nasal mucus. A person is infectious only during the first phase of the disease, and only those living in prolonged close contact with the infected person are at risk. Leprosy is probably spread by droplet infection through sneezing and coughing. In those with untreated leprosy, large amounts of bacteria are found in nasal discharge; the bacteria travel through the air in these droplets. They can survive three weeks or longer outside the human body, in dust or on clothing. Although relatively infectious, leprosy is still one of the least contagious of all diseases. This-together with the fact that only 3 percent of the population are susceptible to leprosy-means that there is no justification for the practice (still prevalent in some countries) of isolating patients. Only a few people are susceptible because most people acquire a natural immunity when exposed to the disease. Most of the body's destruction is caused not by bacterial growth but by a reaction of the body's immune system to the organisms as they die. In lepromatous leprosy, damage is widespread, progressive, and severe. Tuberculoid leprosy is a milder form of the disease.
Symptoms - Damage is first confined to the nerves supplying the skin and muscles, destroying nerve endings, sweat glands, hair follicles, and pigment-producing cells. It first causes a lightening (or darkening) of the skin, with a loss of feeling, and sweating. Some types of the disease produce a rash of bumps or nodules on the skin. As the disease progresses, bacilli also attack peripheral nerves; at first patients may feel an occasional "pins and needles" sensation or have a numb patch on the skin. Next, patients become unable to feel sensations such as a light touch or temperature. Gradually, even hands, feet, and facial skin eventually become numb as muscles become paralyzed. Delicate connections between nerve cells and nerve endings are severed, and whole sections of the body become totally numb. For example, if the nerve above the elbow is affected, part of the hand becomes numb and small muscles become paralyzed, leading to curled fingers. When a patient can no longer sense pain, the body loses the automatic withdrawal reflex that protects against trauma from sharp or hot objects, leading to extensive scarring or even loss of fingers and toes. Muscle paralysis can lead to further deformity, and damage to the facial nerve means eyelids can't close, leading to ulceration and blindness. Direct invasion of bacteria may also lead to inflammation of the eyeball, also leading to blindness.
Treatment - Several antibiotic agents are effective against leprosy and are best used in combinations of two or three. This multidrug therapy is the current preferred treatment: it combines dapsone, clofazimine, and rifampin. Multi-drug therapy was developed as leprosy bacilli became resistant to the sulfone drug dapsone alone after decades of constant use. The most powerful of these three drugs is rifampin, a drug first used against tuberculosis and found to be effective against leprosy in 1968. Particular combinations of these drugs were recommended in 1984 by the World Health Organization as standard treatment for mass campaigns against leprosy. The three drugs are often distributed in blister packs containing a month's supply of pills; dapsone is taken daily, clofazimine is taken every other day, and rifampin is taken monthly. Now there are more than 1 million people receiving these drugs worldwide, and more than 1 million others who have already completed treatment.