CHARACTERIZING ANTIBIOTIC RESISTANCE IN SINGAPORE WATER BODIES AND

CHARACTERIZING ANTIBIOTIC RESISTANCE IN SINGAPORE WATER BODIES AND TRIBUTARIES Name: Chen Hongjie Supervisor: A/Prof. Karina Gin Yew-Hoong Department of Civil and Environmental Engineering © Copyright National University of Singapore. All Rights Reserved.

OUTLINE - Background Information - Objective - Methodology - Results and Discussions - Conclusion

BACKGROUND INFORMATION © Copyright National University of Singapore. All Rights Reserved. Downloaded from http: //www. mirror. co. uk/news/technology-science/humansfacing-antibiotic-apocalypse-papercuts-6862186

BACKGROUND INFORMATION Download from http: //www. nature. com/news/2011/110216/full/news. 2011. 46. html#B 1 © Copyright

BACKGROUND INFORMATION Bacteria posing high health risk/s - Carbapenem resistant Enterobacteriaceae (CRE) - Extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae - Vancomycin resistant Enterococcus (VRE) © Copyright National University of Singapore. All Rights Reserved.

BACKGROUND INFORMATION Singapore - “The Little Red Dot” Monsoon Season - Northeast monsoon (wetter) - Southwest monsoon (dryer) Credits to Google Maps © Copyright National University of Singapore. All Rights Reserved.

BACKGROUND INFORMATION Singapore - Has catchment area of two-thirds of Singapore area - Water structures built to keep in fresh water - to be supplied as drinking water - Important to maintain good water quality standard - Monitor levels of antibiotic resistance © Copyright National University of Singapore. All Rights Reserved.

Objective and Methodology © Copyright National University of Singapore. All Rights Reserved.

OBJECTIVE - Investigate the abundance and percentage resistance of ARB - Investigate if there

METHODOLOGY Sampling Details - 4 water bodies - 4 tributaries - Across 4 months

METHODOLOGY - W 1 - T 1 T 2 - W 2 - T 3 T 4 High level of anthropogenic activity Near residential and commercial area W 2 surrounded by heavy industries Tributaries surrounded by vegetable and animal farms © Copyright National University of Singapore. All Rights Reserved. - Largely forested and protected - W 3 Zoo near W 3 Generally least impacted by human - Largely forested and protected W 4

METHODOLOGY 1 • Filter 100 m. L through 0. 45 µm cellulose nitrate membrane 2 • Place membrane on selective agar 3 • Inoculation and enumeration © Copyright National University of Singapore. All Rights Reserved.

METHODOLOGY No Antibiotics Amikacin Ceftazidime Ciprofloxacin Co-trimoxazole Meropenem No Antibiotics Ciprofloxacin Meropenem Vancomycin E. coli (TBX) Enterococcus spp. (Slanetz and Bartley agar) Klebsiella pnuemoniae (Klebsiella selective agar) Pseudomoas aeruginosa (Cetrimide agar) Salmonella spp. (SS agar) Minimum Inhibitory Concentrations (MIC) of Antibiotics in agar (mg/L) Ciprofloxacin E. coli P. aeruginosa Enterococcus spp. K. pneumoniae Salmonella spp. Amikacin Co-trimoxazole Ceftazidime Meropenem Vancomycin 0. 5 2 2 0. 5 32 32 32 4/76 8 16 8 8 2 4 4 2 2 8 - (2015 Clinical and Laboratory Standards Institute performance standards for Antimicrobial Susceptibility Test) © Copyright National University of Singapore. All Rights Reserved.

Results and Discussion © Copyright National University of Singapore. All Rights Reserved.

RESULTS AND DISCUSSION Taxonomical Correlation (Abundance) - K. pneumoniae had the highest overall resistance - Resistance to Cotrimoxazole and Ciprofloxacin were the highest - Resistance to Amikacin was generally low except for P. aeruginosa ARB concentrations based on each taxa and resistance © Copyright National University of Singapore. All Rights Reserved.

RESULTS AND DISCUSSION Taxonomical Correlation (Percentage Resistance) - Observational pattern similar between % resistance and abundance for E. coli - Salmonella spp. had the highest percentage resistance against Meropenem Percentage resistance based on each taxa and resistance © Copyright National University of Singapore. All Rights Reserved.

RESULTS AND DISCUSSION Temporal Correlation - No significant difference across the months (p > 0. 05) - Need more time points Total ARB concentration based on sampling months and average monthly rainfall © Copyright National University of Singapore. All Rights Reserved.

RESULTS AND DISCUSSION Spatial Correlation Water Bodies - WB 1 is significantly higher than other WB (p < 0. 05) - High level of anthropogenic activity in WB 1 - Insignificant among WB 2, WB 3, WB 4 (p >0. 05) Total ARB concentration based on tributary locations © Copyright National University of Singapore. All Rights Reserved.

RESULTS AND DISCUSSION Spatial Correlation Tributaries - Significantly higher than WB (p < 0. 05) - Difference between T 1, T 2 and T 3, T 4 insignificant (p > 0. 05) Total ARB concentration based on tributary locations © Copyright National University of Singapore. All Rights Reserved.

RESULTS AND DISCUSSION Principle Component Analysis © Copyright National University of Singapore. All Rights

CONCLUSION - Amikacin can still be a relevant antibiotic clinically - K. pneumoniae had the highest resistance in terms of abundance - Salmonella spp. had significantly high percentage resistance against Meropenem - Tributaries had higher abundance of ARB than water bodies. WB 1 had higher abundance than other WB - Land uses could be a major factor for abundance of ARB in water © Copyright National University of Singapore. All Rights Reserved.

A/Prof. Karina Gin Dr. Ng Shi Min Charmaine Dr. Le Thai Hoang Dr. Laurence Haller Dr. Yi Xin Zhu Fang Da Nurhizam Hakim ACKNOWLEDGEMENT This research grant is supported by the Singapore National Research Foundation under its Environmental & Water Technologies Strategic Research Programme and administered by PUB (Project ID: 1102 -IRIS-12 -02) © Copyright National University of Singapore. All Rights Reserved.