New recommendations and perspectives for the control of tuberculosis

This report summarises the ATC/CDC recommendations on the diagnosis and treatment of latent tuberculosis infection. Based on the sensitivity and specificity of the tuberculin skin test and the prevalence of TB in different groups, 3 cut-off levels have been proposed for defining a positive tuberculin reaction: > or =5 mm, >/=10 mm and > or =15 mm of induration. Treatment can be carried out mainly with Isoniazid, but there are alternatives such as Rifampin plus Pyrazinamide in the following cases: when Isoniazid-resistant M. tuberculosis appears and when the treatment is to be shortened; Rifampin alone for persons who cannot tolerate Pyrazinamide. Rifabutin can be substituted for Rifampin in HIV+ patients taking some protease inhibitors and non-nucleoside reverse transcriptase inhibitors. In persons who have been infected with multidrug resistant strains, Ethambutol and Pyrazinamide or Pyrazinamide and a fluoroquinolone can be prescribed. On the other hand, for a general prophylaxis BCG vaccination is not usually recommended due to its variable effectiveness, except in children and health care workers exposed continually to an untreated patient or to one with multidrug resistant M. tuberculosis strains. In order to achieve a new vaccine, a programme is currently being developed in the European Union called "The cluster for Tuberculosis vaccine development", which involves four main projects: optimisation and preclinical evaluation of TB vaccines, development of new live attenuated vaccines, non-protein antigens for TB vaccine and identification of mechanisms and indicators of protective immunity.