VASCO: The ever-increasing menace of multi-drug resistant bacteria has now spread as far as the Arctic region.
A study by a team of researchers from National Centre for Polar and Ocean Research (NCPOR), Goa has found the potential role of a long-distance migratory bird, the Arctic Tern (Sterna paradisaea) in the spread of multidrug resistant bacteria across far and wide destinations, especially to the polar environments.
Twelve major bacterial types were identified from Arctic tern cloacal samples, which are dominated by Staphylococcus and Aerococcus pathogens. The bacterial isolates showed resistance against 16 antibiotics (before migration) and 17 antibiotics (after migration) out of 17 antibiotics tested.
“The increasing prevalence of antibiotic resistance is a global problem that increases the pathogenicity of microorganisms, thus affecting human beings. Antimicrobial-resistant bacteria (ARB) have been reported from polar environments, and migratory birds can act as carriers of micro-organisms across geographical boundaries because of their flying abilities,” Group Director Arctic Operations, NCPOR Dr K P Krishnan told Herald.
Arctic terns are known for their longest migration in the world. They annually migrate back and forth over 80,000 km between the breeding areas in the Arctic and the non-breeding regions of the Antarctic.
“So, this study was conducted to explore the role of Arctic Terns in the dissemination of multidrug-resistant bacteria to the Arctic environment,” he said.
“The study was also conducted to understand the connection with their migratory route,” Dr Krishnan said.
The study titled Dissemination of multidrug resistant bacteria to the polar environment –‘Role of the longest migratory bird Arctic Tern (Sterna paradisaea)’ has been published in the ‘Science of the Total Environment’ journal.
According to P V Vipindas, Project Scientist at Arctic Ecology and Biogeochemistry Division, NCPOR, who is also one of the co-authors of the study, said that during their stopovers, migratory birds may intermix with other migratory and local birds, which may lead to an exchange of pathogenic bacteria through contact.
“Consequently, Arctic terns may become long-distance vectors and potential reservoirs for a wide range of pathogenic and antibiotic-resistant microorganisms that can be transmissible to the Arctic Circle,” Dr Vipindas said.
For tracking their geographic locations and migratory path, the birds (22 Arctic Terns) were live captured using tent spring traps placed on their nests in breeding colonies in Longyearbyen town and tagged with multi-sensor archival data loggers (geolocators). Then they were tracked throughout the annual cycle.
“Our findings suggested that the terns travelled with several stopovers along the polluted Coasts of America, Africa, and Europe. And these areas could be potential locations from where antibiotic bacteria entering to their bodies through direct or sexual contact with other birds and finally reach to the cloaca (a cavity in the pelvic region)of the birds,” the scientist said.
According to him, the long-term implications of this problem are that climate change is also changing the migration pattern of migratory birds because both the phenology and distributions of migratory birds respond to environmental changes.
“Therefore, the sites that migratory birds visit change over time in response to climate change. This is important because climate change may therefore lead to birds dispersing ARB to new areas that are not currently used,” he said.