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Tuberculosis (TB) is caused by the Mycobacterium tuberculosis complex. The majority of active TB is pulmonary (70%), while the remainder is extra‐pulmonary (30%). Patients with active pulmonary TB will typically present with cough, scant amounts of non‐purulent sputum, and possibly hemoptysis. Systemic signs such as weight loss, loss of appetite, chills, night sweats, fever, and fatigue may also be present. EMS clinicians are unlikely to distinguish pulmonary TB from other respiratory illnesses. However, certain risk factors may alert them to the possibility of tuberculosis. These are immigration from a high‐prevalence country, homelessness, exposure to active pulmonary TB, silicosis, HIV infection, chronic renal failure, cancer, transplant recipient, or any other immunosuppressed state [10, 11]. About half of the world’s TB cases, and two‐thirds of all new cases, come from eight countries: Bangladesh, China, India, Indonesia, Nigeria, Pakistan, Philippines, and South Africa [12, 13].

Active pulmonary TB is transmitted via droplet nuclei from people with pulmonary tuberculosis during coughing, sneezing, speaking, or singing. Procedures such as intubation or bronchoscopies are high risk for the transmission of TB. Respiratory secretions on a surface rapidly lose the potential for infection. The probability of infection is related to duration of exposure, distance from the infected person, concentration if bacilli in droplets, ventilation in the room, and the susceptibility of the exposed person. Effective medical therapy eliminates communicability within 2‐4 weeks of starting treatment [14].

If transporting a patient who is known or suspected to have TB, respiratory precautions should be followed by EMS clinicians, including use of N95 respirators, as these types are necessary for infections that are spread via the airborne route. Patients should cover their mouths when coughing or sneezing or wear a surgical mask. In the event of suspected exposure to a patient with active pulmonary tuberculosis, report the case and the exposure to the EMS system or public health authority. Close contacts should be monitored for the development of active TB symptoms. Two tuberculin skin tests should be performed, based on public health recommendations, on those closely exposed to patients with active TB [15]. Because the incubation period after contact ranges from 2 to 10 weeks, the first test is typically done as soon as possible after exposure, and the second test is typically done eight to 12 weeks after the exposure. If the EMS clinician or contact develops either active TB with symptoms or latent asymptomatic TB, as diagnosed with a new positive TB skin test, treatment should be offered.

There are several treatment regimens for latent TB infection [13]. The CDC and the National Tuberculosis Controllers Association recommend either 3 months of once‐weekly isoniazid plus rifapentine, 4 months of daily rifampin alone, or 3 months of daily isoniazid plus rifampin. Short‐course regimens are effective, safe, and have higher completion rates than traditional 6‐ to 9‐month courses of isoniazid monotherapy. They also have lower risk of hepatotoxicity. For active TB, a four‐drug regimen typically includes isoniazid, rifampin, pyrazinamide, and ethambutol, with an intensive phase of all four drugs daily for 8 weeks, followed by a continuation phase including isoniazid and rifampin daily for an additional 18 weeks [16]. Several forms of multi‐drug‐resistant TB and extensively drug‐resistant TB have been identified [17]. Multi‐drug‐resistant TB is treatable and curable by using second‐line drugs. However, second‐line treatment options are limited and require extensive chemotherapy (up to 2 years of treatment) with medicines that are expensive and toxic. These forms require aggressive, multi‐drug regimens for prolonged periods, and are dependent on the organism’s patterns of drug sensitivity and resistance. In all cases, a physician skilled in management of TB must initiate and monitor treatment and provide suitable follow‐up. Tuberculosis is a reportable disease, and public health officials must be notified to ensure appropriate follow‐up and contact tracing.