Scientists have discovered antibiotic resistant (AR) gene NDM-1 (New Delhi metallo-beta-lactamase 1) in pristine high Arctic region (Kongsfjorden region of Svalbard), one of the earth’s most remote spots. It highlights further indication of globalisation of antimicrobial resistance (AR).
New Delhi metallo-beta-lactamase 1 (NDM-1)
- It is enzyme that makes bacteria resistant to broad range of beta-lactam antibiotics. It includes antibiotics of carbapenem family, which are used for treatment of AR bacterial infections.
- Its gene is one member of large gene family that encodes beta-lactamase enzymes called carbapenemases.
- Bacteria that produce carbapenemases are often referred as "superbugs" because infections caused by them are difficult to treat.
- NDM-1 was first detected in a Klebsiella pneumoniae isolate from Swedish patient of Indian origin in 2008 in New Delhi, so it is named after it.
- Most common bacteria that make this enzyme are gram-negative such as E-coli and Klebsiella pneumonia. Its gene can spread from one strain of bacteria to another by horizontal gene transfer.
Findings of Study
- It was detected in five out of the eight clusters studied. It was present in highest concentrations near fresh water sources where wildlife tends to congregate.
- Robust presence of blaNDM-1 comparatively localised in Kongsfjorden pose no health threat, but its detection reinforces how rapidly AR can globalise.
- Additionally, levels of mobile genetic elements (MGEs), a mechanism by which bacteria trade AR, to mirror NDM-1 was also discovered.
- MGEs are noteworthy in this region because they are often associated with acquired resistance and are found at higher levels in human, or animal waste-impacted environments.
- AR in essence is natural phenomenon as most antibiotics are produced by soil microorganisms and over time they have evolved to become resistant to the compounds which they excrete to survive.
- Reasons for spread of superbug: Involvement of migratory birds is considered as prime reason. Birds might have carried resistance in their gut and transfered it to Arctic soil through faecal matter.
- However, it is also possible that it may have migrated with humans also and spread via local wildlife, or it may be combination of factors.