About

Kevin Cummings, DVM, PhD, is an Associate Professor in the Department of Population Medicine and Diagnostic Sciences at Cornell University College of Veterinary Medicine. His primary research interest is the application of epidemiologic approaches to investigate the ecology and transmission of Salmonella and other foodborne pathogens among a wide variety of hosts, ranging from dairy cattle to wild birds. His overarching goals are to enhance food safety, improve health among animal populations, and mitigate the emergence and dissemination of antimicrobial resistance. Dr. Cummings holds a PhD in Comparative Biomedical Sciences with a focus on Epidemiology from Cornell University and a DVM from the same institution. His professional experience includes roles as an Assistant Professor of Epidemiology at Texas A&M University, where he was approved for tenure and promotion to Associate Professor, and as an adjunct instructor at the University of Minnesota. He has also worked as a practicing veterinarian and has been involved in various research and teaching activities related to veterinary medicine, epidemiology, and public health.

Research topics

• Internal medicine
• Medicine
• Pharmacology
• Family medicine
• Emergency medicine

Selected publications

• Motile and non-motile <i>Listeria</i> species adopt distinct genomic and ecological strategies to achieve broad geographic ranges in soil

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-01-09

  articleOpen access

  Abstract Broad geographic ranges indicate high ecological versatility and are generally associated with low extinction risk. Motility is not only a physiological feature, but also a core ecological trait for bacteria. However, the genomic foundations underlying the broad geographic ranges of motile and non-motile bacteria remain poorly understood. To address this, we analyzed 141 and 90 genomes of Listeria welshimeri and L. booriae , systematically screened from 1,004 soil samples across the United States, representing widespread motile and non-motile species, respectively. We show that L. welshimeri exhibits restricted phylogeographic structure and a weak distance-decay relationship, suggesting minimal geographic barriers to dispersal. Its high dispersal capacity likely stems from enhanced motility and effective host colonization, evidenced by strong positive selection on flagellar genes and the close relatedness to isolates from wild birds. In contrast, L. booriae displays a regionally endemic distribution and limited dispersal. With a large, open pangenome, L. booriae appears strongly adapted to local environments. This is evidenced by pronounced positive selection on genes involved in inorganic ion, amino acid, and coenzyme transport and metabolism, as well as strong associations with abiotic factors, particularly climate, and accompanying bacterial consortia. In summary, to establish widespread distributions, L. welshimeri tends to rely on movement and colonization of wildlife hosts to facilitate long-distance dispersal, while L. booriae leverages genomic plasticity and metabolic versatility that enable adaptation to diverse environmental conditions. These findings highlight the distinct genomic foundations and ecological strategies that motile and non-motile bacteria use to achieve broad geographic ranges in the environment.

  PublisherOA PDFDOI

• Comparison of PCR and culture for detection of <i>Campylobacter jejuni</i> in canine feces

  Journal of Veterinary Diagnostic Investigation · 2026-04-15

  articleOpen access

  Campylobacter jejuni is a leading cause of human foodborne illness, and pet dogs can be a source of infection. Despite recognition of this zoonotic potential, tests for detection of C. jejuni are not performed routinely in dogs. We compared bacterial culture and molecular methods for the detection of C. jejuni directly from canine feces and from Bolton enrichment broth inoculated with feces in a multi-laboratory randomized-method test. Although culture offers the advantage of collection of isolates for further epidemiologic study, real-time PCR (rtPCR) to detect cpn60 from DNA isolated directly from canine feces was more sensitive than culture and more accurate than rtPCR using DNA isolated from enrichment cultures. The limit of detection for our cpn60 rtPCR was 320 cfu/g.

  PublisherOA PDFDOI

• Prevalence of SARS-CoV-2 infection and immunity in a New York county in 2022 reveals frequent asymptomatic or undiagnosed infections

  PLoS ONE · 2025-05-28

  articleOpen accessCorresponding

  Accurate and timely surveillance of SARS-CoV-2 prevalence and immunity is critical to local and national COVID-19 pandemic responses. Representative surveillance surveys reveal more accurate estimates of COVID-19 infection than other measures based on reported test results. Our main research objectives were (i) to provide local health department officials with prevalence estimates calculated from a representative sample to better inform their decision-making efforts in response to the COVID-19 pandemic and (ii) to identify characteristics associated with COVID-19 infections among high-risk groups. Three municipalities were sampled at one timepoint (February, April, or October 2022) using a 2-stage cluster sampling design. Participants provided anterior nares swabs, which were tested for SARS-CoV-2 with a RT-PCR and for nucleocapsid protein and receptor binding domain antibodies by multiplex Luminex assay. Participants completed a survey on socio-demographics, SARS-CoV-2 prevention behaviors and attitudes, and vaccination and infection history. A total of 233 individuals from 221 households provided anterior nares swabs, and 215 samples were linked to survey data. After adjusting for study design, the household prevalence of PCR-positive tests was less than 5%, but approximately half of the population had antibodies from a prior infection and most (81% to 92%) had antibodies from either infection or vaccination. Discrepancies between self-reported positive test and vaccination status and antibody results suggested a high prevalence of asymptomatic infection and waning antibody titers. County-level infection prevalences, estimated from the county test reporting system, were 16.6% in February, 19.1% in April, and 23.8% in October, substantially lower than the prevalence of individuals with antibodies from infection in the surveys, also supporting a high prevalence of asymptomatic or unconfirmed infections. The overall small sample size precluded an analysis of characteristics associated with active or past infection. In conclusion, surveillance surveys can provide timely data on infection status and immunity to support public health responses.

  PublisherDOI

• Retrospective analysis of antimicrobial susceptibility testing illustrates the problem of resistant Staphylococcus species in cats in the northeastern United States

  Preventive Veterinary Medicine · 2025-08-25

  article
  PublisherDOI

• The impact of antimicrobial use regulations on antimicrobial resistance among Salmonella isolates from bovine samples submitted to a veterinary diagnostic laboratory in Central New York

  One Health · 2025-06-01

  articleOpen access

  In recognition that antimicrobial resistance in human pathogens may stem from antimicrobial use in agricultural settings, the United States Food and Drug Administration (FDA) ordered restrictions on antimicrobial usage (AMU) in food-producing animals. In 2012 the FDA restricted the extra-label use of third-generation cephalosporins, and in 2017 the FDA mandated veterinary oversight for the use of antimicrobials in the feed and water of food-producing animals and eliminated production-related uses. However, the impact of these restrictions on the antimicrobial resistance status of important pathogens, such as Salmonella , remains unclear. To address this gap in knowledge, we analyzed veterinary diagnostic laboratory data on 2413 Salmonella isolates from submitted bovine samples. We fitted logistic regression models to evaluate changes in proportions of antimicrobial-resistant isolates, and we used accelerated failure time (AFT) models to determine changes in minimum inhibitory concentration (MIC) values. Our analysis revealed the 2012 AMU restriction to be associated with a decrease in the odds of resistance to chlortetracycline (OR = 0.49; 95 % CI = 0.28–0.86), oxytetracycline (OR = 0.47; 95 % CI = 0.27–0.82), and neomycin (OR = 0.45; 95 % CI = 0.25–0.80). Furthermore, we found significant decreases in MIC values for chlortetracycline (CR = 0.74; 95 % CI = 0.62–0.87) and oxytetracycline (CR = 0.64; 95 % CI = 0.56–0.73) for the same AMU restriction. We found a significant association between the 2017 AMU restriction and decreased odds of resistance to florfenicol (OR = 0.28; 95 % CI = 0.09–0.92). Salmonella serotype was an important predictor of resistance to all antimicrobials assessed via logistic regression or AFT models. Overall, our study suggests that in the region served by the laboratory, AMU restrictions have either had no detectable effect or are associated with decreasing AMR and MIC trends for Salmonella isolated from bovine samples, depending on the antimicrobial.

  PublisherDOI

• Evidence of transmission and dissemination of diverse <i>bla</i> _NDM-5 -producing <i>Escherichia coli</i> clones between refugee and host communities and their environment: a multicenter cross-sectional study

  Applied and Environmental Microbiology · 2025-11-04 · 1 citations

  articleOpen access

  ABSTRACT The global spread of carbapenemase-producing Escherichia coli (CP-Ec) poses a significant public health threat, with particularly severe consequences for vulnerable populations in resource-limited settings. To address this, we conducted in-depth genetic analyses and examined the relatedness of CP-Ec isolates recovered from hospitalized patients, refugees, animals, water, and environmental sources within refugee camps and in marginalized host communities in Lebanon. Nineteen putative CP-Ec isolates, identified by MALDI-TOF MS and designated as community isolates, harbored either NDM ( n = 17) or OXA-48-like ( n = 2) carbapenemases. We used whole-genome sequencing (WGS) to characterize the resistomes and sequence types of these isolates. To further examine genetic relationships and transmission dynamics, we also analyzed publicly available (EnteroBase) CP-Ec genomes from Lebanon ( n = 64) and across the globe ( n = 447 recovered in 2022) alongside 31 additional clinical CP-Ec isolates from the same geographic region. The community isolates belonged to ST10, ST167, ST361, ST410, ST617, ST648, ST940, ST1284, and ST5842. Both community and clinical CP-Ec isolates carried multiple acquired antimicrobial resistance (AMR) genes and chromosomal mutations, with 82% harboring the bla NDM-5 gene. Core-genome SNP analysis showed that refugee isolates clustered with global CP-Ec genomes, highlighting their genomic relatedness and potential for geographical dissemination. Furthermore, integration of our data with previously reported Lebanese genomes demonstrated the spread of bla NDM-5 -carrying E. coli across different hosts and niches, emphasizing the complex interplay of AMR within the human-animal-environment interface. The coexistence of carbapenemase genes with mobile genetic elements that enable horizontal gene transfer raises concerns about the emergence of highly resistant and hypervirulent CP-Ec lineages, especially in vulnerable populations and settings. IMPORTANCE The global rise of CP-Ec strains harboring bla NDM-5 has been increasingly documented in clinical settings. However, little is known about their emergence and transmission in refugee settlements. This study provides a high-resolution genomic characterization of CP-Ec isolated from human, animal, water, and environmental sources in refugee settlements and surrounding host communities. By integrating whole-genome sequencing data from clinical isolates collected in Lebanese hospitals, we reveal genetically related strains in both community and healthcare settings, highlighting the potential introduction of community-acquired strains into clinical environments and vice versa. The widespread detection of bla NDM-5 across multiple reservoirs suggests sustained circulation beyond hospital settings. The identification of CP-Ec in river water used for irrigation and emptying into the Mediterranean Sea highlights wider environmental dimensions that may drive regional dissemination of AMR. Our findings highlight the urgent need for One Health-based AMR surveillance strategies to track the spread of carbapenem-resistant pathogens in high-risk settings.

  PublisherDOI

• Use of the Salmonella Dublin ELISA demonstrates varying seroprevalence across age groups at dairy heifer–raising facilities in New York

  American Journal of Veterinary Research · 2025-12-17

  articleOpen access

  Objective: To investigate the role of dairy heifer-raising facilities as a possible source of exposure to Salmonella Dublin. We hypothesized that heifers near the time of departure to the home farms are more likely to have been exposed to S Dublin in comparison to heifers near the time of arrival at the heifer-raising facility. Methods: At 5 enrolled heifer raisers, we collected serum samples from animals within 3 different age groups: 3 to 4 months (age group 1), 10 to 12 months (age group 2), and 20 to 22 months (age group 3). All serum samples were tested for S Dublin antibodies using the PrioCHECK S Dublin ELISA kit. Results: Age group 2 had the highest proportion of ELISA-positive animals (35 of 149 [23.5%]), and age group 2 had increased odds of ELISA positivity relative to the other age groups (OR, 3.95; 95% CI, 1.91 to 8.14). Age group 2 also had the highest median ELISA percentage of positivity value (3; range, -14 to 222), with differences between age groups 1 and 2 and groups 1 and 3. Conclusions: These observations suggest that animals at heifer-raising facilities are likely to be exposed to S Dublin prior to 10 to 12 months of age and are continuously exposed to this serotype at the raising facilities. Clinical Relevance: These findings can be used to guide decision-making on the use of off-site heifer-raising facilities and inform the development of targeted management protocols to reduce the risk of S Dublin exposure among animals arriving at these operations.

  PublisherDOI

• Antimicrobial use in equine patients at a veterinary teaching hospital in the northeastern United States reveals opportunities for enhanced stewardship

  Journal of the American Veterinary Medical Association · 2025-10-08

  article

  Objective: To assess the use of systemic antimicrobial agents in equine patients and identify areas where their use could be reduced. Methods: A retrospective study evaluating the electronic medical records for all equine visits in which systemic antimicrobials were given at a veterinary teaching hospital for 1 year (2021). Negative binomial regression analysis was used to evaluate factors associated with antimicrobial prescription rate. Results: Systemic antimicrobials were prescribed for 33.5% (543 of 1,622) of equine visits. For most visits (89.1%), ≤ 3 antimicrobials were given. The antimicrobial prescription rate was higher in patients with confirmed or suspected infection and in patients that died or were euthanized. Highest-priority critically important antimicrobials were used infrequently (13.6% [74 of 543]). Equine patients undergoing clean surgeries (n = 122) received antimicrobials on the day of surgery, with many receiving > 24 hours of treatment (65). Approximately 24% of nonsurgical patients received antimicrobials when there was no evidence of infection. Culture was performed infrequently (15.7%). Conclusions: Systemic antimicrobials were given during a third of the equine visits in 2021. The limited use of highest-priority critically important antimicrobials suggests that clinicians were not using these medications for first-line treatment. Areas for improvement include documenting the clinician's justification for antimicrobial use along with type, duration, and reasons for de-escalation and/or escalation of therapy; reducing perioperative use, especially for clean surgeries; and increasing the submission of samples for culture. Clinical Relevance: Antimicrobial resistance continues to be a global concern, and veterinarians can reduce the use of antimicrobials by critically evaluating their own use and modifying behaviors to align with current evidence-based recommendations.

  PublisherDOI

• Antimicrobial resistance and virulence patterns of Helicobacter pylori among patients with suspected peptic ulcer disease in disenfranchised settings

  Infectious Medicine · 2025-12-25

  articleOpen access

  • Helicobacter pylori clarithromycin resistance has reached alarming levels in Lebanon. • Culture and Allplex™ H pylori and ClariR Assay concurred in 91% of cases. • In-depth genomic data on H. pylori resistance is urgently needed. The epidemiology of Helicobacter pylori in Lebanon is underreported. We aimed to estimate the infection proportion, clarithromycin resistance, and virulence determinants of H. pylori among symptomatic patients with suspected peptic ulcers in Tripoli, North Lebanon. Eighty-seven patients undergoing routine endoscopy screening for peptic ulcers were selected. Culture and Allplex™ H. pylori and ClariR Assay were performed. Antimicrobial susceptibility testing for clarithromycin, tetracycline, levofloxacin, and rifampicin was performed using the E-test method. The virulence factors ( cagA, vacA, dupA, iceA1, iceA2 , and oipA ) were screened and/or typed by PCR. Overall, 32.2% (28/87) of the patients were found to be infected with H. pylori . Five isolates were resistant to clarithromycin, associated with specific point mutations of A2143G (4/5) or A2142C (1/5). The vacA was found in all tested isolates, with s2m2 being the predominant vacA genotype. The 3′ end variable region of cagA was identified in 44.4% of isolates, where cagA typing indicated their belonging to Western types. The other virulence determinants were dupA (77.8%), iceA1 (61.1%), oipA (55.6%), and iceA2 (50%). Our findings demonstrate the circulation of H. pylori among symptomatic patients with suspected peptic ulcers in Lebanon, characterized by a rich and diverse pool of virulence genes and the emergence of resistance to clarithromycin and levofloxacin. Large-scale surveillance is crucial for quantifying the burden of H. pylori infection, monitoring antimicrobial resistance trends, and ensuring timely updates to eradication treatment policies.

  PublisherDOI

• Antimicrobial use regulations are associated with increased susceptibility among bovine Salmonella isolates from a U.S. surveillance system

  One Health · 2025-01-31

  articleOpen access

  Health authorities around the world have called to limit antimicrobial use in food-producing animals. In the United States, two recent regulatory actions have changed the use of antimicrobials in livestock, banning production uses in 2017 and restricting extra-label use of cephalosporins in 2012. This study aimed to assess the impact of the 2012 and 2017 regulations on antimicrobial use in cattle in the United States by analyzing 18,627 bovine Salmonella AMR susceptibility patterns using data from the National Antimicrobial Resistance Monitoring System (NARMS). Logistic regression was used to model the odds of being a susceptible isolate. Additionally, interval-censored accelerated failure time (AFT) models were used to analyze changes in minimum inhibitory concentrations (MICs) over time and by serotype. The most common serotypes were Montevideo ( n = 3003), Anatum ( n = 1394), Cerro ( n = 1373), and Typhimurium ( n = 1213). Susceptibility was highest for azithromycin (99 %), ciprofloxacin, gentamicin, and trimethoprim-sulfamethoxazole (all 98 %), and lowest for tetracycline (76 %), chloramphenicol (86 %), and ampicillin (85 %). Serotypes Typhimurium, Newport, and Dublin exhibited lower susceptibility compared to other serotypes. Susceptibility to all antimicrobials increased during the periods 2013–2017 and 2018–2022 compared to isolates before 2012, with a greater increase in 2018–2022. MICs decreased for most antimicrobials except for chloramphenicol and gentamicin, which showed increased median MIC for the periods 2013–2017 and 2018–2022, respectively. In conclusion, antimicrobial use restrictions appear correlated with a reduction in Salmonella AMR, although this effect cannot be untangled from the effect of time in this dataset. • Increased antimicrobial susceptibility in Salmonella after antimicrobial regulation. • Greater increase in susceptibility and MIC reduction in 2018–2022 than 2013–2017. • Salmonella serotype is strongly associated with antimicrobial resistance.

  PublisherDOI

Frequent coauthors

• Lorin D. Warnick

  New York State College of Veterinary Medicine

  73 shared

• Julie D. Siler

  Cornell University

  63 shared

• Martin Wiedmann

  Cornell University

  57 shared

• Yrjo T. Gröhn

  51 shared

• Emily Wright

  45 shared

• Karin Hoelzer

  44 shared

• Margaret A. Davis

  42 shared

• Shelley M. Zansky

  Centers for Disease Control and Prevention

  38 shared

Labs

• Kevin Cummings LabPI

Awards & honors

• Biosafety and Biosecurity Section Oral Presentation Award fo…