Antibiotic was discovered dated back in 1928, has helped to save millions of people from the infectious disease that was once considered fatal in the 19th century. Nevertheless, the overuse of antibiotics such as clinical misuse and inside livestock could induce the potential emergence of antibiotics-resistance gene (ARG) inside the human body or even in the environment. In 2018, World Health Organization has reported ARG as one of the enormous threats to global health, food security and development. This study was examining the concentration of two antibiotics of interest, Clarithromycin and Ciprofloxacin in one of the drainage discharge channels that serves the treated wastewater. It was reported that wastewater treatment plant is the major source of the antibiotic present in the water stream, whereas the emergence of the antibiotic-resistant bacteria is observed at the middle part of the discharge channel, coming from the wet market influent, located 260m away from the wastewater inlet. Continuous 18 months of Ciprofloxacin and Clarithromycin measurement throughout the discharge channel indicated that there is no external pharmaceutical inflow into the channel, and the average concentration are 1.947 mg/L and 0.5051 mg/L respectively. Nevertheless, discharge affluent from the wet market was found out to contain a significant amount of ARG bacteria, with the range of 40-50 CFU/mL and 50-2000 CFU/mL for Ciprofloxacin and Clarithromycin resistant respectively.
Resistance gene measurement indicates that approximately 0.27%, 2.97% and 0.34% of the total microorganism inside the discharge channel are resistant to Ciprofloxacin, Clarithromycin and both Ciprofloxacin and Clarithromycin respectively. Multifunctional hydrogel, developed by HKUST team in 2015, has been utilized to eradicate the ARG bacteria developed throughout the discharge channel. The hydrogel encapsulates metabolic inhibitor that would be continuously released once the hydrogel is in contact with water. It is reported to reduce the total aerobic bacteria by 60-80% and total anaerobic bacteria by 60-65% during the two trial studies. On the same test, the hydrogel is also capable to curtail 70-75% and 65-70% of Ciprofloxacin-resistant and Clarithromycin-resistant bacteria respectively.
