Ethical issues in tuberculosis vaccine trials

Bacille Calmette-Guerin (BCG) vaccines are widely used, even though estimat es of efficacy have ranged from zero to 80%. BCG is a relatively safe vacci ne, but it can cause disseminated infection, especially in immunocompromise d hosts. Thus, the development of a more reliably efficacious and safer vac cine is important to the control of tuberculosis, The testing of any new va ccine in human populations presents a number of ethical challenges that mus t be addressed. These include (1) the appropriateness of conducting such tr ials in developing countries; (2) the use of a BCG-vaccinated population as the control group; (3) the provision of tuberculin skin-test screening and preventive therapy to study participants; (4) the involvement of various " communities" in the trial(s); (5) the structure and process of ethical revi ew; (6) establishing an effective method of obtaining informed consent; and (7) the roles and responsibilities of researchers and others in ensuring t hat trial results are available to the study population after the trial end s.