Antibiotic Resistant Escherichia Coli in Non-Tidal Wetlands of Maryland Speakers: Neil Agarwal & Robert Vocke III University of Maryland, College Park

Establishing a Baseline MDE Clean Water Act Antibiotics

Site Overview Non-tidal, mitigation sites 3 plots per site

Data Collection Vegetation Soils Land Use Water Quality Antibiotic Resistance

Our focus today… Water quality data Why Antibiotic Resistance? The Concept of Measuring Resistance Preliminary Results

Water Quality Results Nitrate (mg/L)

Water Quality (continued) Ammonia (mg/L)

Water Quality (continued) Total N (mg/L)

Water Quality (continued) Total P (mg/L)

Why look at antibiotic resistance? The pharmaceutical problem Antibiotics and resistance Testing for antibiotic resistance is cost effective Questions to be asked: Prevalence and temporal changes Correlation to other aspects of health Resistance ‘sinks’ Nutrient Cycling

Disk Diffusion: The Concept Image courtesy of http://biology.clc.uc.edu/fankhauser/Labs/Microbiology Image courtesy of http://jyi.org/articleimages/555/

Disk Diffusion: The Concept Image courtesy of http://www.wings-china.com/showinfo.asp?typeid=24&xxid=554&Language=En

Fleming’s Discovery Image courtesy of http://www.accessexcellence.org/AE/AEC/CC/s5.html

Disk Diffusion: The Procedure Image courtesy of http://jyi.org/articleimages/555/

Disk Diffusion: The Procedure Image courtesy of http://jyi.org/articleimages/555/

Disk Diffusion: The Procedure Image courtesy of http://jyi.org/articleimages/555/

Disk Diffusion: The Procedure Image courtesy of http://jyi.org/articleimages/555/

Disk Diffusion: The Procedure Image courtesy of http://jyi.org/articleimages/555/

Disk Diffusion: The Procedure Image courtesy of http://jyi.org/articleimages/555/

Our specific procedure Collected surface samples Serial dilutions Culture on ColiBlue

ColiBlue media Red = Coliforms Blue = E. Coli

Our specific procedure Collected surface samples Serial dilutions Culture on ColiBlue Isolate a single E. coli colony Disk diffusion using 5 antibiotics: Ampicillin Erythromycin Tetracycline Sulfisoxazole Ciprofloxacin Negative Control: Vancomycin

Converting Inhibition Zones CLSI standard Example: Ampicillin with 7mm zone of inhibition <13 mm = Resistant 14-16 mm = Intermediate >17 mm = Susceptible

Converting Inhibition Zones CLSI standard Example: Ampicillin with 7mm zone of inhibition <13 mm = Resistant 14-16 mm = Intermediate >17 mm = Susceptible

Results of Testing Ampicillin Tetracycline Ciprofloxacin Sulfisoxazole Susceptible 1 2 32 11 Intermediate 5 13 12 Resistant 27 18 Total 33 34 % Resistant 82% 55% 0% 32%

What’s next? Find correlations to health Test upstream & downstream Effect on nutrient cycling

Antibiotic Resistant Escherichia Coli in Non-Tidal Wetlands of Maryland Speakers: Neil Agarwal & Robert Vocke III University of Maryland, College Park