Patients' perceptions and experiences of directly observed therapy for TB

Tuberculosis (TB) is caused by a bacterium (Mycobacterium tuberculosis). When people with active TB in their lungs or throat cough, sneeze or spit, they can propel TB germs into the air which can be breathed in by others. A person need only inhale a single bacterium to become infected. TB usually affects the lungs, causing consolidation and tissue destruction, but can spread from the lungs to other parts of the body such as the spine, other organs and lymph nodes, causing serious infection. People with active TB in their lungs can infect 5–15 other people through close contact over the course of a year. Without proper treatment, 45% of people with active TB who are HIV negative and nearly all people with active TB who are HIV positive will die (World Health Organization (WHO), 2021).

Drug-sensitive TB is treated with a combination of antibiotics, usually 6 months of rifampicin and isoniazid augmented with ethambutol and pyrazinamide for the first 2 months. Severe cavitary pulmonary disease may need a longer course of treatment (9–12 months) and nearly all patients will experience undesirable side effects ranging from fatigue, nausea and vomiting through to rashes and liver toxicity. Drug-resistant strains of TB, however, require longer courses of treatment of between 9 and 24 months and include the use of second-line antibiotics with profound side-effects such as ototoxicity, gastrointestinal and central nervous system disturbances, dermatological changes and arthralgia.