Antibiotic-resistant Gram-negative Bacteria in Urban Flies, and the Increased Risk Posed by Open-air Markets in Mexico City
Microbiology Research Journal International,
Aims: Flies are known to spread antibiotic resistant bacteria (ARB), especially from farms to cities; but they may also play a role in the intra-urban dispersion of ARB, in conjunction with poor sanitary conditions. Here, we characterized gram-negative ARB isolated from urban flies (Lucilia and Sarcophaga spp.), and the co-relation with the periodic installation of two open-air markets in Mexico City.
Methodology: Forty-two flies were individually captured, and 116 gram-negatives (68 of them Escherichia coli) were isolated from them. Resistance prevalence, and the presence of class 1 integrons was assessed.
Results: The isolates were resistant to an average of 2.26 antibiotics (2.6 for E. coli), and 33% of E. coli isolates carried the intI1 gene. Thirteen percent of E. coli isolates produced extended-spectrum beta-lactamases (ESBL), all of them CTX-M, alone or, mostly, along TEM enzymes. Comparing data from market-free days vs. days when open-air markets were installed, the average number of resistance phenotypes per E. coli isolate went from 2.14 to 3.09; the number of resistance phenotypes per fly from 4.62 to 8.88; the average number of resistances per isolate per fly from 1.25 to 2.43; and the ESBL-producing carriage rate per fly from 0.08 to 0.38, respectively (P <.05). Other resistance parameters, were consistently higher among flies captured on market days, but differences were not significant.
Conclusion: Urban flies in Mexico City carry a high number of gram-negative ARB; the presence of open-air markets significantly increase the risk of fly-mediated ARB spreading to the neighboring areas.
- Antibiotic resistance
- Escherichia coli
- open-air market
How to Cite
Amábile-Cuevas CF. Antibiotics and antibiotic resistance in the environment. Leiden: CRC Press/Balkema; 2016.
Onwugamba FC, Fitzegerald JR, Rochon K, Guardabassi L, Alabi A, Kühne S, et al. The role of 'filth flies' in the spread of antimicrobial resistance. Travel Med. Infect. Dis. 2018;22:8-17.
Zurek L, Ghosh A. Insects represent a link between food animal farms and the urban environment for antibiotic resistance traits. Appl. Environ. Microbiol. 2014;80:3562-3567.
CLSI. Performance standards for antimicrobial susceptibility testing, 30th ed. Wayne: Clinical and Laboratory Standards Institute; 2020.
Roe MT, Vega E, Pillai SD. Antimicrobial resistance markers of class 1 and class 2 integron-bearing Escherichia coli from irrigation water and sediments. Emerg. Infect. Dis. 2003;9:822-826.
Monstein H-J, Östholm-Balkhed Å, Nilsson MV, Nilsson M, Dornbusch K, Nilsson LE. Multiplex PCR amplification assay for the detection of blaSHV, blaTEM and blaCTX-M genes in Enterobacteriaceae. APMIS. 2007;115:1400-1408.
Drieux L, Brossier F, Sougakoff W, Jarlier V. Phenotypic detection of extended-spectrum β-lactamase production in Enterobacteriaceae: review and bench guide. Clin. Microbiol. Infect. 2008;14 (suppl. 1):90-103.
Cristóbal-Azkarate J, Dunn JC, Day JMW, Amábile-Cuevas CF. Resistance to antibiotics of clinical relevance in the fecal microbiota of Mexican wildlife. PLoS One. 2014;9:e107719.
Rosas I, Salinas E, Martínez L, Cruz-Córdova A, González-Pedrajo B, Espinosa N, et al. Characterization of Escherichia coli isolates from an urban lake receiving water from a wastewater treatment plant in Mexico City: fecal pollution and antibiotic resistance. Curr. Microbiol. 2015;71:490-495.
Díaz-Mejía JJ, Amábile-Cuevas CF, Rosas I, Souza V. An analysis of the evolutionary relationships of integron integrases, with emphasis on the prevalence of class 1 integron in Escherichia coli isolates from clinical and environmental origins. Microbiology. 2008;154:94-102.
Wetzker W, Pfeifer Y, Wolke S, Haselbeck A, Leistner R, Kola A, et al. Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli isolated from flies in the urban center of Berlin, Germany. Int. J. Environ. Res. Public Health. 2019;2019:1530.
Petridis M, Bagdasarian M, Waldor MK, Walker E Horizontal transfer of Shiga toxin and antibiotic resistance genes among Escherichia coli strains in house fly (Diptera: muscidae) gut. J. Med. Entomol. 2006;43:288-295.
Amábile-Cuevas CF. Antibiotic usage and resistance in Mexico: an update after a decade of change. J. Infect. Dev. Ctries. 2021;15:442-449.
Abstract View: 65 times
PDF Download: 22 times