Meat as a source of multidrug-resistant bacteria in lower- and middle-income countries

  • Antibiotic misuse in humans and animals contributes to the development of antibiotic-resistant bacteria.
  • As countries develop, more people want to eat meat and fish as part of their daily diet.
  • The animal farms that are proliferating to meet this demand often rely on routine antibiotic administration to animals to quickly grow large numbers in confined spaces.
  • In LMICs, limited oversight of this practice plus weaker public health protections could contribute to the spread of of MDR bacteria from farmed animals to the community.

Key publications:

Nadimpalli M, Yith V, de Lauzanne A, et al. Meat and fish as sources of extended-spectrum B-lactamase-producing Escherichia coli, Cambodia. Emerg Infect Dis 2019; 25(1). [link]

Nadimpalli M, Fabre L, Yith V, et al. CTX-M-55-type ESBL-producing Salmonella enterica are emerging among retail meats in Phnom Penh, Cambodia. J Antimicrob Chemother 2018. doi: 10.1093/jac/dky451. [link]

Nadimpalli M, Delarocque-Astagneau E, Love DC, et al. Combating Global Antibiotic Resistance: Emerging One Health Concerns in Lower and Middle-Income Countries (Editor's Choice). Clin Infect Dis. 2018;66(6):963-969. doi:10.1093/cid/cix879. [link]

Improving water, sanitation, and hygiene to combat antibiotic resistance

  • Improved water, sanitation and hygiene in human communities and “biocontrol” in animal production could help reduce antibiotic demand and prevent the spread of drug-resistant bacteria and resistance genes into the environment.
  • My ongoing research indicates that WASH and biocontrol interventions are especially needed in settings that are rapidly urbanizing and where livestock production is intensifying.

Key publications:

Nadimpalli ML, Marks S, Montealegre MC, et al. Urban informal settlements as hotspots of antimicrobial resistance and the need to curb environmental transmission. Nat Microbiol. 2020;5, 787–795. doi: https://doi.org/10.1038/s41564-020-0722-0 [link]. Editorial titled "Antimicrobial resistance in the age of COVID-19" about this publication: [link]

Nadimpalli ML, Viau R, Stegger M, et al. Common mobile genetic element harboring blaCTX-M-55 and qnrS in diverse human- and animal-origin Escherichia coli, Cambodia. Applied Bioinformatics & Public Health Microbiology. June 5-7, 2019. Hinxton, UK.

Using genomics to investigate global spread of antibiotic-resistant bacteria and genes

  • Combining sequencing data with epidemiological information can provide insight into AMR transmission at the hospital, household, and population level, as well as the emergence of new "high-risk" bacterial clones.

This ongoing work is in collaboration with Statens Serum Institute, George Washington University, Institut Pasteur Paris, and Tufts University.

Key publications and presentations:

Aziz, M, Nicholson A, Nadimpalli ML, et al. Outbreaks of Klebsiella pneumoniae in Special Care Nurseries (SCNs) in Jamaica: Role of Whole Genome Sequencing. ID Week. October 2-6, 2019. Washington, D.C.

Nadimpalli ML, de Lauzanne A, Phe T, et al. Escherichia coli ST410 among humans and the environment in Southeast Asia. Int J Antimicrob Agents. 2019;54(2):228-232. doi: 10.1016/j.ijantimicag.2019.05.024. [link]

Exposure to zoonotic Staphylococcus aureus among industrial hog operation workers and their household contacts in the USA

  • Industrialized systems of food animal production are a potential source of exposure to antibiotic-resistant Staphylococcus aureus.
  • Healthy individuals who have frequent contact with intensively-raised livestock, such as hog operation workers, have a higher risk of exposure to zoonotic S. aureus.
  • Through human cohort and environmental sampling studies, we are examining occupational activities that may be associated with exposure, health implications of exposure, and dissemination of these bacteria into the household environment via environmental or occupational pathways.
  • We aim to conduct research that can empower citizens to improve community health.

Key publications:

Nadimpalli ML, Stewart JR, Pierce E, et al. Face mask use and persistence of livestock-associated Staphylococcus aureus nasal carriage among industrial hog operation workers and household contacts, USA. Environ Health Perspect 2018;126(12). [link]

Nadimpalli M, Rinsky JL, Wing S, et al. Persistence of livestock-associated antibiotic-resistant Staphylococcus aureus among industrial hog operation workers in North Carolina over 14 days. Occup Environ Med 2015; 72:9-99. [link]

Rinsky JL, Nadimpalli M, Wing S, et al. Livestock-Associated Methicillin and Multidrug Resistant Staphylococcus aureus Is Present among Industrial, Not Antibiotic-Free Livestock Operation Workers in North Carolina. PLoS One. 2013;8(7):e67641. [link]

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