Also known as consumption. TB is caused by an infection of any one of several species of the Mycobacterium, also known as tubercle bacillus. In humans, most TB is caused by M. Tuberculosis, although cases involving the bovine counterpart M. Bovis are not uncommon. Pigs and birds can also get their own variants of the disease. Tuberculosis has been known of for millennia; the ancient Egyptians and Hippocrates both knew of the disease, and pretty much every urban society since then. In the 1800s, TB was practically an epidemic, being the leading cause of death in industrialized countries for all age groups. These days, you hardly hear of it outside of the Third World.

TB can be contracted in two ways: By either breathing M. Tuberculosis from the same air as a TB sufferer, or by drinking milk contaminated with M. Bovis. The parts of the body attacked by the disease are the parts related to how it was contracted. The human type resides in the lungs as pulminary TB. The cattle type affects the bones and joints of the body, kind of like drinking antimilk.

Once in the body, TB will eat and reproduce where it can until the body forms a protective wall around the affected area known as a Tubercle. The tubercle is microscopic in and of itself, but large formations of tubercles can form a cheese-like mass in the affected tissue, hampering proper organ function.

Pulmonary TB occurs in childhood, and is usually exhibits no symptoms when it first infects. If the child is lucky, the bacteria will be destroyed, and all they'll have to show for it is a small scar. If they're not lucky, the bacteria will spread into the blood stream, which is highly fatal if drugs are not properly administered.

Postprimary pulmonary TB is historically known as the disease Consumption. It occurs in adolescents and adults, and is characterized by a lack of energy, weight loss, and coughing. Oddly enough, women with consumption were considered more feminine in Victorian times, due to their unnatural fragility and constant plight, echoed in the goth look today. This attraction probably faded as the disease spread, causing chest pain, sweating, and blood in the saliva. If left unchecked, the patient will begin to cough up blood as the bacteria eat away at the lungs, and soon the lack of proper lung tissue is enough to prove fatal, from either lack of oxygen or exhaustion.

Diagnosing pulmonary TB is easy: Just put some spit under a microscope and look for tubercles. If you don't like spit, you can also check the urine or the stool, or you can avoid touching the patient altogether and take an X-ray of the lungs and look for scars. A skin test is available to determine whether a subject is immune to TB or not.

Avoiding TB is also easy, if you live in a developed country. Keep good hygiene, only drink pateurized milk, and avoid contact with people who have pulmonary TB, and you should be OK. There is also a BCG vaccine composed of weakened tubercles that can be used to immunize against the disease.

Even treatment of TB is easy, these days. Whereas in previous centuries you were prescribed years of bed-time and several surgical procedures to remove tubercles, (and trust me, you didn't want to undergo surgery back then), these days there are several drugs that will kill TB dead.

The fact that diagnosis, prevention, and treatment of TB is so simple makes it even more tragic that children still die from this disease in third-world countries.

Thanks to britannica.com for most of the info, except for the victorian females thing, which came from The Big Book of Death