Colistin and carbapenems are two categories of antibiotics utilized as a last-resort treatment for infections caused by multi-drug resistant (MDR) and extensively drug resistant (XDR) bacteria. Resistance to these last lines of defence can eventuate total antibiotic resistance. At present, there is scarcity of research present to estimate the current load and impact of the residual concentrations of colistin and carbapenems on environmental microbiome. However, there have been several reports demonstrating resistance development to colistin and carbapenems in a range of environmental compartments in the past few years. Most of their dosage is discharged as waste in its original form, thereby making its way into the urban wastewater. Expected low environmental concentrations, complex structures, stability, and interfering substances make quantification of colistin and carbapenems from environmental samples extremely challenging. There are a few major knowledge gaps addressed in this PhD
This study identified the stability of two categories of last-resort antibiotics: colistin (colistins A and B) and carbapenems (meropenem, doripenem, biapenem, and ertapenem) in water and wastewater. Colistin and carbapenems at −20 °C showed a considerable degradation over 3 weeks, with the highest decay noted for ertapenem. Under an acidic pH, all carbapenems showed a comparable level of decay in both water and wastewater. However, under neutral pH, the degradation under wastewater (kww = 0-0.0117 h-1) was higher than in water (kw = 0-0.0042 h-1). For colistin at pH 7, degradation observed in wastewater within 24 h was significantly higher than that in water, with an observed kww of 0.44 h-1 (pH 7, 25 °C) in comparison to a kw of 0.0128 h-1. Temperature deteriorated the stability of colistin in wastewater at pH 7, as the degradation at 4 °C (40-50%) was much lower than that at 25 °C (80-90%). The stability of colistin A and B was identical in both water and wastewater under acid
The widespread use of antibiotics in livestock farming has led to the emergence of bacteria that are more resistant to the human immune system. A study conducted by scientists at the University [.]
A recent study coordinated by the University of Oxford (Oxon) found that the global trade of the "last-resort" antibiotic colistin is driving the spread of dangerous superbugs in low- [.]
As I write this article, our area has a winter storm approaching, and our community is scrambling to prepare. Grocery stores are trying to keep up with demand, schools are