Tuberculosis (TB) is a bacterial infection most commonly spread from person to person through the air by coughing and sneezing. Globally the disease is extremely common with millions of new infections and many deaths occurring yearly. The rate of disease varies widely from country to country, with the highest rates and most deaths occurring in developing regions for example Sub-Saharan Africa and South East Asia.
Most travellers visiting countries with high rates of TB are at low risk of infection. Travellers at higher risk include those visiting friends and relatives, healthcare workers, long-term travellers, and those who have contact with a person who has active infection. Prolonged exposure to infected individuals is usually required for infection to occur.
Most healthy individuals who are infected will never develop active disease as their immune system is able to contain the disease. Those most likely to develop active infection include: young children and persons with underlying health problems (for example HIV, cancer, poorly controlled diabetes, long-term kidney disease and malnutrition).
Although TB may affect any organ it most commonly affects the lungs (pulmonary TB). The disease often occurs without symptoms and when symptoms do occur they depend on the organ affected. Symptoms of pulmonary TB commonly include: fever, night sweats, weight loss and a productive cough. Treatment can be complicated and involves prolonged courses of antibiotics. In recent decades TB has become increasingly resistant to many antibiotics.
Travellers should avoid close contact with individuals known to have infectious pulmonary TB. Those at risk during their work (such as healthcare workers) should take appropriate infection control precautions that may include isolation and barrier nursing procedures.
In the United Kingdom, vaccination against TB (BCG vaccine) forms part of the national immunisation programme and is targeted to high-risk individuals, including some travellers.
TB vaccine is recommended for the following two groups of travellers:
Bacillus Calmette-Guerin (BCG Vaccine), Statens Serum Institute
Infants below 12 months:
Children aged 12 months and over and adults: 0.1ml/intra-dermal
Vaccination requires intra-dermal injection and should be carried out by healthcare professionals trained in this technique.
Although immunity may wane over time, reinforcing doses are not recommended. There is no evidence that they would confer additional protection and there is a risk of adverse reactions. There is little evidence of vaccine efficacy in those aged 16 years and older, so vaccination is only recommended for such individuals in special circumstances.