Context

• In samples collected from Sabarmati River, two lakes and three effluent treatment plants, researchers find microorganisms to be drug resistant.

About

About:

• It is found that pollution, whether in a lake or at a point of sewage discharge into a river, induced multi-drug anti-microbial resistance in collected samples of E Coli bacteria possibly transforming it into what is known as a superbug.
• The Asia Pacific Network for Global Change Research is funding the project, in collaboration with University of Kanazawa and University of Tokyo from Japan, University of Ruhuna from Sri Lanka and IIT-Gandhinagar from India.
• Samples collected from:As part of the project, IIT-Gandhinagar team collected water samples from lakes Kankaria and Chandola, the Sabarmati river and three effluent treatment plants (both in flow and outflow) in Ahmedabad.
• Samples tested with:Six different kinds of antibiotics like ciprofloxacin, norfloxacin, tetracyclin and kanamycin for antibiotic resistance.

Findings:

• In Sabarmati, they collected samples from three different locations — Nehru Bridge (upstream), Sardar Bridge (middle) and Fatehwadi (downstream).
• While the sample from Nehru Bridge showed the E Coli was not resistant to any antibiotics.
• But in the Sardar Bridge sample, 60 per cent of the E Coli was resistant to kanamycin and 40 per cent of the bacteria were resistant to other five drugs.
• But the resistance again decreased to zero further downstream in Fatehwadi showing that the river had a natural way of dealing with the phenomenon if not polluted again.
• Similarly, in the samples collected from ChandolaLake, 80 per cent of the bacteria were multi-drug resistant.

What caused the resistance to go up at Sadar Bridge?

• Sabarmati does not have a high natural flow during summers but the riverfront needs water at all times. So, the water is stored at SardarBridge and remains stagnant. This stagnant water probably makes the E Coli antibiotic resistant.

Treatment plants:

• The most surprising results came from the treatment plants.
• In all three treatment plants from where samples were collected and tested, the resistance was higher in the effluents than in the influents.
• On the other hand, the density of E Coli had decreased after treatment. This means that though the treatment had killed the bacteria, the ones that did get saved had evolved to higher antibiotic resistance.
• One possible reason for this could be genetic mutation due to ultra-violet radiation treatment or even chlorination.
• Since E Coli multiplies really quickly, creating new generations in 15-60 minutes, the gene transfer from one generation to the next will happen rapidly which could explain the escalation of resistance and also its quick downfall.

E Coli E. coli (Escherichia coli), is a type of bacteria that normally lives in your intestines. It’s also found in the gut of some animals. Most types of E. coli are harmless and even help keep your digestive tract healthy. But some of them can cause severe diarrhoea, pneumonia, urinary tract infection (UTI), cholecystitis and neo-natal meningitis. Some versions of E. coli make you sick by making a toxin called Shiga. This toxin damages the lining of your intestine. The strains of E. coli that make the toxin are sometimes called STEC, which is short for “Shiga toxin-producing E. coli.”