Why is TB becoming harder to treat?
Over time, the TB germ slowly figures out how to resist being killed by the major TB drugs, especially when the drugs are not taken properly. Some strains, or specific varieties, of TB have become resistant to at least one of the major anti-TB drugs, meaning that fewer weapons are available to fight the infection. These strains are called drug-resistant TB. There are two kinds of TB drug resistance. The first, called acquired drug resistance, is usually caused by improper treatment of TB disease. Improper treatment results from one or more of four different causes: 1) patients do not take all their drugs every day for the required period because they start feeling well, 2) only one drug (see the list above) was used for treatment, 3) doctors prescribe the wrong treatment, or 4) the drug supply is poor and it runs out during treatment. The second, called primary drug resistance, happens when a person becomes infected with a strain of TB that is already resistant to anti-TB drugs. The re
