First approach to the population structure of Mycobacterium tuberculosis complex in the indigenous population in Puerto Nariño-Amazonas, Colombia

INTRODUCTION: Tuberculosis affects vulnerable groups to a greater degree, indigenous population among them. OBJECTIVE: To determine molecular epidemiology of clinical isolates of Mycobacterium tuberculosis circulating in an indigenous population through Spoligotyping and 24-loci MIRU-VNTR. METHODOLOGY: A descriptive cross-sectional study was conducted in 23 indigenous communities of Puerto Nariño-Amazonas, Colombia. Recovered clinical isolates were genotyped. For genotyping analyzes global SITVIT2 database and the MIRU-VNTRplus web portal were used. RESULTS: 74 clinical isolates were recovered. Genotyping of clinical isolates by spoligotyping determined 5 different genotypes, all of them belonged to Euro-American lineage. By MIRU-VNTR typing, a total of 14 different genotypes were recorded. Furthermore, polyclonal infection was found in two patients from the same community. The combination of the two methodologies determined the presence of 19 genotypes, 8 formed clusters with 63 clinical isolates in total. Based on epidemiological information, it was possible to establish a potential chain of active transmission in 10/63 (15.9%) patients. CONCLUSIONS: High genomic homogeneity was determined in the indigenous population suggesting possible chains of active transmission. The results obtained showed that specific genotypes circulating among the indigenous population of Colombia are significantly different from those found in the general population.