Microbial contamination and antimicrobial resistance patterns in the Mississippi Gulf Coast

Maitreyee Mukherjee, Robyn Cuthbert, Kristi Gay, Emma Aitken, and Karah LeBuda, Department of Biological, Environmental, and Earth Sciences, University of Southern Mississippi Gulf Park Campus, 730 E Beach Blvd, Long Beach, MS 39560

Background: Microbial contamination and spread of antimicrobial resistance and multidrug resistance in various environments, particularly in water sources, is a global emerging public health concern. The Mississippi Gulf Coast is a very important resource for recreation, public use, travel, and economic purposes. Therefore, it is important to monitor, understand and mitigate the occurrence and distribution of pathogens and drug resistance here as collecting such data will help improve the state’s environmental and public health control measures and is an important resource for keeping our coast clean and sustainable.


Methods: In this study, we collected and analyzed surface ocean water samples from ten sites across the Mississippi Gulf Coast over a period of 5 months for the following: 

1) Enumerate pathogenic bacteria using EPA methods 1603 (E. coli) and 1600 (Enterococcus)

2) Identify the patterns of drug-resistance with Kirby-Bauer disc diffusion method 


Results: Data collected over five months suggest the prevalence of concerning levels of indicator bacteria (E. coli) in coastal waters within all sites sampled across the Mississippi Gulf Coast. The E. coli numbers ranged between 120 – 990 cfu/ 100 ml, falling well beyond the water quality standards set by EPA for recreational waters (126 E. coli/ 100 ml). We also detected high levels of erythromycin resistance within the isolated E. coli from these samples – 99-100%- as well as high resistance to the antibiotics Ampicillin, Tetracycline, Cephalothin and Amoxycillin. Moreover, many of the isolates showed high numbers of multidrug resistance (resistant to ≥2, ≥3 and ≥4 antimicrobial agents) on most sites across all sampling events. 


Future Directions: 

·        Continue sampling and analyses through 2021 to gather data over seasonal variations

·        Quantitative PCR analysis of antibiotic resistance genes across all samples.

Additional Abstract Information

Presenter: Robyn Cuthbert

Institution: University of Southern Mississippi

Type: Poster

Subject: Microbiology

Status: Approved

Time and Location

Session: Poster 8
Date/Time: Tue 5:00pm-6:00pm
Session Number: 5647