Molecular epidemiology of Mycobacterium tuberculosis strains from prison populations in Santa Catarina, Southern Brazil

The Tuberculosis (TB) notification rates are 5 to 81 times higher in prisons worldwide when compared to the general population. The state of Santa Catarina (SC) has few epidemiological data regarding TB in prisons. The aim of this study was to evaluate the molecular epidemiology of circulating strains in prisons of SC. The study comprised 95 clinical samples from six prisons. Among the cases included, all subjects were male, predominantly caucasians, and young adults, with low education level. The positive smear in the TB diagnosis comprised 62.0% of cases. About 50% of subjects had some condition associated with TB. The Spoligotyping results showed that the most frequent lineages were LAM (50.7%), T (22.2%) and S (11.6%). The 12-loci MIRU generated 62 different genotypes. The MSTs showed evolutionary relationships between Mycobacterium tuberculosis spoligotypes from SC and evolutionary relationships between the prison isolates and studied parameters. This first study on TB in prison units of SC highlighted the predominance of SIT216/LAM5, and SIT34/S. Interestingly, his profile was found to be different from that observed in a previous study performed with the state's general population. This data shows the need for continued surveillance of episodes of TB occurring among prison inmates in an emerging country like Brazil. •A super representation of the S lineage was observed among the prison population.•The MST analysis confirmed the unique nature of the large clusters comprised of LAM.•There is a predominance of SIT216/LAM5 almost exclusively in one prison unit.•The SIT34/S in majority was from the southern region of the state.•The profile found in prisons is different from the observed in general population.