Vaccination against TB is also addressed in chapter 17.
In practice, the only available vaccine is the bacille Calmette-Guérin (BCG), which dates back to the early 20th century. Millions of doses of BCG have been used worldwide with a reported good safety profile and efficacy in preventing invasive TB in children. However, the protection induced against pulmonary TB, both in children and adults, is incomplete and the results of epidemiological studies on the duration of protection are inconsistent. In immunocompromised (HIV-infected) subjects, BCG vaccination seems to be associated with a higher risk of complications and even dissemination of BCG infection.
The rate of BCG vaccination in children in the EU is variable. Policies range from no use of BCG at all to vaccination of all children at birth, in infancy, at school entry and in later school years. Rates of infant vaccination in different EU and non-EU countries are presented in figure 4.
The World Health Organization (WHO) in Europe recommends that BCG vaccination should not be administered to HIV-positive children in areas with low TB incidence; in areas with high TB incidence, BCG vaccination should be restricted to HIV-positive children who do not have symptoms. WHO does not recommend BCG vaccination for adolescents and adults, including those with HIV infection, due to little or no evidence of protection from pulmonary TB.
New vaccines have been developed, including both therapeutic vaccines for immune therapy as an adjunct to chemotherapy, and potential preventive vaccines. Clinical trials are ongoing to test their efficacy.