Prisoners Open to Tuberculosis Vaccine Trials, but Want Transparency

Tuberculosis remains a global public health challenge, and prisons in low- and middle-income countries are among the places with the highest rates of disease. That makes people deprived of liberty — who live in crowded, high-risk settings — an important group to consider when new TB vaccines are introduced. But including incarcerated people in clinical research carries special ethical weight because of a long history of exploitation and mistreatment in medical studies. To understand how people living in prison settings view this issue, a team led by Júlio Croda set out to hear their perspectives directly. The research aimed to learn how incarcerated individuals perceive TB, vaccines in general, and the idea of participating in clinical trials of new TB vaccines, at a time when several TB vaccine candidates are advancing to late-stage clinical trials. Rather than rely on outside assumptions, the study put the experiences and voices of people deprived of liberty at the center, asking what conditions would make them willing — or unwilling — to join vaccine research while emphasizing respect, transparency, and informed choice.

This was a multicenter qualitative study that used focus group (FG) discussions to gather firsthand views. The research took place in seven state prisons across four of the five regions of Brazil and involved 91 incarcerated people (64 men and 27 women) who were interviewed between February and August 2024. Participants were selected through convenience sampling and the FGs followed a standardized structure that explored perceptions about health in prisons, tuberculosis, vaccines in general, new TB vaccines, and potential participation in research. The discussions were transcribed verbatim and analyzed using thematic content analysis. Participants reported problems accessing healthcare within the prison system and described personal or indirect experiences with TB, as well as worries that family members outside could be exposed. While overall attitudes toward vaccines and vaccine trials were generally positive, willingness to participate depended on having clear, transparent information, respect for individual autonomy, and guarantees of accountability from researchers.

The study highlights that prior experiences with prison health services and the level of trust in research institutions strongly shape whether people deprived of liberty would join vaccine trials. Ethical inclusion of incarcerated populations will therefore require more than scientific rationale: it demands practical safeguards such as clear communication about risks and benefits, robust informed consent processes, and visible accountability measures to prevent coercion or harm. Because prisons concentrate both high disease risk and social vulnerability, responsibly including these populations in TB vaccine research could accelerate evaluation and eventual deployment of effective vaccines where they are most needed. At the same time, researchers and institutions must address historical and present injustices to build trust, uphold autonomy, and ensure that participation is truly voluntary and informed.