Background Zoonotic tuberculosis is defined as human infection with Mycobacterium bovis. Although globally, India has the largest number of human tuberculosis cases and the largest cattle population, in which bovine tuberculosis is endemic, the burden of zoonotic tuberculosis is unknown. The aim of this study was to obtain estimates of the human prevalence of animal-associated members of the Mycobacterium tuberculosis complex (MTBC) at a large referral hospital in India. MethodsWe did a molecular epidemiological surveillance study of 940 positive mycobacteria growth indicator tube (MGIT) cultures, collected from patients visiting the outpatient department at Christian Medical College (Vellore, India) with suspected tuberculosis between Oct 1, 2018, and March 31, 2019. A PCR-based approach was applied to subspeciate cultures. Isolates identified as MTBC other than M tuberculosis or as inconclusive on PCR were subject to whole-genome sequencing (WGS), and phylogenetically compared with publicly available MTBC sequences from south Asia. Sequences from WGS were deposited in the National Center for Biotechnology Information Sequence Read Archive, accession number SRP226525 (BioProject database number PRJNA575883). Findings The 940 MGIT cultures were from 548 pulmonary and 392 extrapulmonary samples. A conclusive identification was obtained for all 940 isolates; wild-type M bovis was not identified. The isolates consisted of M tuberculosis (913 [97•1%] isolates), Mycobacterium orygis (seven [0•7%]), M bovis BCG (five [0•5%]), and nontuberculous mycobacteria (15 [1•6%]). Subspecies were assigned for 25 isolates by WGS, which were analysed against 715 MTBC sequences from south Asia. Among the 715 genomes, no M bovis was identified. Four isolates of cattle origin were dispersed among human sequences within M tuberculosis lineage 1, and the seven M orygis isolates from human MGIT cultures were dispersed among sequences from cattle. Interpretation M bovis prevalence in humans is an inadequate proxy of zoonotic tuberculosis. The recovery of M orygis from humans highlights the need to use a broadened definition, including MTBC subspecies such as M orygis, to investigate zoonotic tuberculosis. The identification of M tuberculosis in cattle also reinforces the need for One Health investigations in countries with endemic bovine tuberculosis. Funding Bill & Melinda Gates Foundation, Canadian Institutes for Health Research.

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Background Recently, in India, there has been a shift from NDM to OXA48-like carbapenemases. OXA-181 and OXA-232 are the frequently produced variants of OXA48-like carbapenemases. OXA48-like carbapenemases are also known to be carried on transposons such as Tn 1999 , Tn 1999.2 and it is also associated with IS1R carried on Tn 1999 . In India, there are no previous reports studying the association of mobile genetic elements (MGEs) with OXA48-like carbapenemases. The present study was aimed at determining the genetic backbone of OXA48-like carbapenemases to determine the role of MGEs in its transfer and to investigate the Inc plasmid type carrying bla OXA48-like . Results A total of 49 carbapenem resistant K. pneumoniae which included 25 isolates from South India and 24 isolates from North India, were included in the study. Whole genome sequencing using Ion Torrent PGM was performed to study the isolates. OXA-232 was present in 35 isolates (71%). In 19 isolates (39%), bla OXA48-like was associated with MGEs. Insertion sequences such as ISX4, IS1, IS3, IS Kpn 1, IS Kpn 26, IS Kpn 25, IS Spu 2, IS Kox 1, IS 4321R , IS Ec 36, and IS Pa 38; and transposons such as TnAs3 and Tn2, were present. Isolates from northern and southern India belonging to same sequence type (ST) had diverse genetic backbone for bla OXA48-like . ST14 isolates from north had IS5 and Tn3 families while from south they had IS1, IS5 and IS630 families. ST231 from north had IS5, IS6 and Tn3 families with bla OXA-232 while from south, IS1, IS3 and IS5 families were observed; with IS Kpn 26 being present among isolates from both the regions. bla OXA48-like was predominantly found on ColKP3 plasmid. ST231 was the predominant ST in 22 isolates (45%). Conclusion OXA-232 is the predominant variant of OXA48-like carbapenemase with ST231 being the commonest ST of OXA48-like carbapenemase producing K. pneumoniae in India. Diverse MGEs have been associated with both bla OXA-232 and bla OXA-181 which contribute to their spread. The MGEs in the present study are different from those reported earlier. There is no clonal expansion of bla OXA48-like producing K. pneumoniae since diverse STs were observed. Monitoring the genetic backbone of OXA48-like carbapenemas...

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