799. Genetic Diversity of Mycobacterium tuberculosis Strains Causing Drug-Resistant Tuberculosis in Central Region of Mozambique: The Whole-Genome Sequencing

BACKGROUND: Knowing the genetic diversity of M. tuberculosis strains causing drug-resistant tuberculosis (DR-TB) in high burden TB and low resources countries such as Mozambique is a key factor to TB disease spread control and world TB epidemic control. Whole-genome sequencing (WGS) better describes molecular diversity, lineages and sub lineages, relationship between strains, underline mutations conferring drug-resistant TB, which may not be shown by molecular and phenotypic tests. As far as we know this is the first study that describes genetic diversity of M. tuberculosis strains causing DR-TB and using WGS in central region of Mozambique.We aim to describe genetic diversity of M. tuberculosis strains causing DR-TB in central Mozambique. METHODS: A total of 35 strains from Beira Mozambique were evaluated with genotypic tests (Genotype MTBDRplus™, and MTBDRsl™); phenotypic (MGIT-SIRE™) and DST. All isolates resistant to isoniazid (H) or rifampicin (R) or both were submitted to WGS Illumina HiSeq 2000 and analyzed with TB profiler database and phylogenetic tree was done using Figtree tool. This was a descriptive cross-sectional study. RESULTS: WGS shown that strains analyzed, belongs to three of six major lineages, with Lineage 4: 25(71.4%); Lineage 1: 5(14.3%); and Lineage 2 Beijing family: 5(14.3%)]. All pre-XDR strains 3(8.6%) were from lineage 4.3. By WGS, all 35 strains had any mutations conferring DR-TB while in one strain, mutation was not shown by genotypic neither phenotypic DST. Compared with genotypic tests, WGS had best performance in showing mutation conferring resistance to etambutol 12/35 (34.3%) and 7/35 (20%). CONCLUSION: The DR-TB disease in Beira Mozambique is mainly caused by M. tuberculosis strains of Lineage 4, sub-lineage 3 although lineage 1 and 2 are also present. WGS shows underline mutations causing DR–TB that are not detected by genotypic and phenotypic DST test. DISCLOSURES: All authors: No reported disclosures.