Primary resistance occurs when a person becomes infected with a resistant strain of TB. A person with fully susceptible MTB may develop secondary (acquired) resistance during therapy because of inadequate treatment, not taking the prescribed regimen appropriately (lack of compliance), or using low-quality medication. Drug-resistant TB is a serious public health issue in many developing countries, as its treatment is longer and requires more expensive drugs. MDR-TB is defined as resistance to the two most effective first-line TB drugs: rifampicin and isoniazid. Extensively drug-resistant TB is also resistant to three or more of the six classes of second-line drugs. Totally drug-resistant TB is resistant to all currently used drugs. It was first observed in 2003 in Italy, but not widely reported until 2012, and has also been found in Iran and India. Bedaquiline is tentatively supported for use in multiple drug-resistant TB. COUNT 5
QSN1 If a person has TB that's resistant to rifampicin and isoniazid, which type of the disease do they have? ANS1 MDR-TB QSN2 What's the minimum number of second-line medication classes your TB would have to resist to make it count as "extensively drug-resistant"? ANS2 three QSN3 In what country was the first case of totally drug-resistant tuberculosis? ANS3 Italy QSN4 What's the only antibiotic that might be effective against totally drug-resistant TB? ANS4 Bedaquiline QSN5 Cases of totally drug-resistant TB have been found in what country in addition to Italy and India? ANS5 Iran