Tuberculosis (TB) is a significant public health problem in Ecuador with an incidence of 43 per 100,000 inhabitants and an estimated multidrug-resistant-TB prevalence in all TB cases of 9%. Genotyping of Mycobacterium tuberculosis (MTBC) is important to understand regional transmission dynamics. This study aims to describe the main MTBC lineages and sublineages circulating in the country. A representative sample of 373 MTBC strains from 22 provinces of Ecuador, with data comprising geographic origin and drug susceptibility, were genotyped using 24 loci-MIRU-VNTR. For strains with an ambiguous sublineage designation, the lineage was confirmed by Regions of Difference analysis or by Whole Genome Sequencing. We show that lineage 4 is predominant in Ecuador (98.3% of the strains). Only 4 strains belong to lineages 2-sublineage Beijing and two strains to lineage 3-sublineage Delhi. Lineage 4 strains included sublineages LAM (45.7%), Haarlem (31.8%), S (13.1%), X (4.6%), Ghana (0.6%) and NEW (0.3%). The LAM sublineage showed the strongest association with antibiotic resistance. The X and S sublineages were found predominantly in the Coastal and the Andean regions respectively and the reason for the high prevalence of these strains in Ecuador should be addressed in future studies. Our database constitutes a tool for MIRU-VNTR pattern comparison of M. tuberculosis isolates for national and international epidemiologic studies and phylogenetic purposes.

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The complete genomic sequence of a variant of the recently reported maize-associated totivirus (MATV) from China was obtained from commercial maize in Ecuador. The genome of MATV-Ec (Ecuador) (4,998 bp) is considerably longer than that of MATV-Ch (China) (3,956 bp), the main difference due to a ≈ 1-kb-long capsid-protein-encoding fragment that is completely absent from the Chinese genome. Sequence alignments between MATV-Ec and MATV-Ch showed an overall identity of 82% at the nucleotide level, whereas at the amino acid level, the viruses exhibited 95% and 94% identity for the putative capsid protein and the RNA-dependent RNA polymerase (RdRp), respectively. Phylogenetic analysis of the viral RdRp domain indicated that MATV-Ec and MATV-Ch share a common ancestor with other plant-associated totiviruses, with Panax notoginseng virus A as the closest relative. MATV-Ec was detected in 46% (n = 80) of maize plants tested in this study, but not in endophytic fungi isolated from plants positive for the virus.

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