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Veterinary Laboratory Investigation and Response Network


Veterinary Laboratory Investigation and Response Network logo - 8/2014


Our Mission

To promote human and animal health by collaborating with veterinary diagnostic laboratories to

  • provide scientific information
  • build laboratory capacity for routine and emergency response
  • train scientists

To help CVM investigate potential problems with CVM-regulated products, including

  • animal feeds
  • animal drugs

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We Investigate Animal Illnesses Caused by Food or Drugs

Is your animal sick? Do you think it was the food? Or a drug?

Submit a Complaint


Figure 1. What Happens During a Case Investigation?

CVM Reviews the complaint for 3 possible actions: regulatory action, monitor for similar complaints, or Vet-LIRN gathers more information. During a Vet-LIRN case investigation, we collect animal medical records and conduct owner interviews. We test animal samples such as stool, urine, blood, and tissue at our network labs. We use this information to decide if the illness was caused by the food or drugs. If likely, FDA initiates possible regulatory action. If unlikely, FDA monitors for similar complaints.

We investigate potential animal food issues (Figure 1).
We are an important part of the food safety team at CVM. 

Learn more about some of our cases:

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Resources for Animal Owners and Veterinarians

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Tracking Antimicrobial Resistance in Bacteria from Sick Animals

Why track resistance in bacteria?

Antimicrobial resistance is an important public health issue because if antibiotics and similar medicines become ineffective, many infections will be more difficult to treat. In March of 2015, a presidential initiative was released to combat antibiotic resistant bacteria. This national action plan guides government, public heath, healthcare, and veterinary partners in addressing antimicrobial resistance. As part of this plan, Vet-LIRN was tasked to develop, expand, and maintain antimicrobial susceptibility testing (AST) and whole-genome sequencing (WGS) testing of veterinary pathogens isolated at veterinary diagnostic laboratories. To successfully monitor the antimicrobial susceptibility of bacterial pathogens, it is vital that veterinary diagnostic laboratories be incorporated into the nation’s other surveillance activities. Vet-LIRN is committed to being a partner in such an effort.

What progress have we made?

  • During 2017-2018, the Vet-LIRN Program Office coordinated a two-year pilot project to evaluate the feasibility of using Vet-LIRN veterinary diagnostic laboratories to monitor the antimicrobial susceptibility of three veterinary pathogens: Escherichia coli and Staphylococcus pseudintermedius in dogs and Salmonella enterica in any host. Approximately 5,000 isolates from clinically sick animals were collected and tested (Figure 2).
  • Twenty Vet-LIRN Source diagnostic laboratories collected isolates and tested the susceptibility using Clinical and Laboratory Standards Institute (CLSI) methods. Additional information about the pathogen (the organ it came from, the animal species, which part of the country) was reported.
  • Each Source lab was partnered with one of four WGS laboratories 
  • WGS laboratories sequenced a subset of the isolates submitted by their Source labs and uploaded all sequences to National Center for Biotechnology Information (NCBI) through the GenomeTrakr program. Approximately 1000 isolates were sequenced 
  • The data so far provides a snapshot of the susceptibility of pathogens being cultured at referral veterinary laboratories. 
  • Vet-LIRN is partnering with the National Antimicrobial Resistance Monitoring System (NARMS) to make the data public.
  • In 2018-2019 additional labs began collecting and sequencing isolates. (Figure 3)

Figure 2. Vet-LIRN AMR Surveillance: what are we doing?

The Source labs collect animal isolates of Salmonella, E. coli,  Staphylococcus pseudintermedius, and others. The labs then perform antimicrobial susceptibility testing and generate a standardized lab report of the results. Isolates are sent from the source labs to the Whole Genome Sequencing labs for sequencing. After the isolate is sequenced, the data is submitted to the National Center for Biotechnology Information for public sharing.

Figure 3: Geographical distribution and organization of Vet-LIRN WGS and Source laboratories (2019)

Map of the United States showing 6 sequencing labs (5 in US and 1 in Canada) and thirty source laboratories (25 in US and 5 in Canada). Almost all states are represented as either a source and/or sequencing lab.

Legend: Thirty source laboratories (25 is the U.S. and 5 in Canada) (squares) are collecting isolates. Six WGS labs (triangles) have five collaborating source labs each and sequence a subset of the isolates submitted by their source labs. Remaining Vet-LIRN laboratories, currently not participating in the project, are shown with circles.

Vet-LIRN Laboratory Funding

Vet-LIRN Cooperative Agreements facilitate participation in Vet-LIRN activities such as case investigations, emergency exercises, proficiency tests, and laboratory accreditation. The agreements also increase the agency’s capability to analyze an increased number of samples in the event of animal food- or drug-related illnesses or other large-scale emergency events that require increased testing of implicated diagnostic or animal food samples. The new agreement allows network laboratories to request additional funds if they are participating in a specific Vet-LIRN project, such as the Antimicrobial Resistance (AMR) Pilot Project or if they are conducting whole-genome sequencing (WGS) work, or if their caseload is particularly heavy.

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Ensuring Accurate Results

A scientist is pipetting liquid into a test tube.

We collaborate with the FDA’s Center for Food Safety and Nutrition (CFSAN) Division of Food Processing Science and Technology (Moffett Center) and the Institute for Food Safety and Health, Illinois Institute of Technology to conduct Proficiency Tests (PTs) and Interlaboratory Comparison Exercises (ICEs) to ensure FDA receives accurate test results from our network laboratories. Samples are sent to the laboratories and test results are submitted to the VPO. Data is evaluated, and final reports are provided to the laboratories.

Proficiency Tests Offered in 2019

1. Detecting Salmonella  Typhimurium and Listeria monocytogenes in raw dog foods
    Timely because of the recent increase in raw pet food recalls due to bacterial contamination with pathogens such as Listeria and Salmonella

2.  Aflatoxin in dog feed
     Assess laboratories’ ability to detect aflatoxin, a known carcinogen, at the level of concern.

3.  Carbamate pesticides in rumen content
     Important diagnostic tool to confirm or rule out exposure to toxic compounds. 

4.  Detecting Campylobacter in dog feces
     Timely due to the recent Campylobacter outbreak related to contact with pet store puppies.

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Veterinary Student Opportunities

Veterinarians are valuable partners in CVM’s mission to promote animal health. Vet-LIRN is committed to building relationships with the next generation of veterinary professionals. Veterinary students can apply for an externship through the FDA Veterinary Clerkship Program to train alongside Vet-LIRN team members. Students will learn more about CVM’s mission.

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Veterinarians, Want to Learn More?

Vet-LIRN educates veterinarians and students about how to identify and report suspected animal food issues via webinars and case studies. Vet-LIRN speaks at various conferences, to veterinary interest groups, and to students. Please contact Dr. Jones if you would like Vet-LIRN to speak to your organization.

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Preparing for and Responding to Emergencies

Vet-LIRN participates in the planning, play, and evaluation of emergency preparedness and response activities. Such activities strengthen the Program Office’s ability to establish and initiate strategies to coordinate the roles and responsibilities of veterinary diagnostics laboratories in real-world emergency events. Knowing the network laboratory capabilities and having routine interactions and exercises with the laboratories is key to any emergency response. Vet-LIRN Program Office routinely communicates with following laboratory networks and programs to harmonize and leverage activities and participate in an integrated response to national emergencies: 

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Vudathala, D., et al., Multilaboratory Evaluation of a Lateral Flow Method for Aflatoxin B1 Analysis in Dry Dog Food. J AOAC Int, 2020. 103 (2): 480-489.

Du, X., et al., Evaluation of a diagnostic method to quantify aflatoxins B1 and M1 in animal liver by high-performance liquid chromatography with fluorescence detection. J AOAC Int. 2019. 102(5) 1530-1534.

Ceric, O., et al. Enhancing the one health initiative by using whole genome sequencing to monitor antimicrobial resistance of animal pathogens: Vet-LIRN collaborative project with veterinary diagnostic laboratories in United States and Canada. BMC Vet Res 15: 130. 2019. 6993016

Jones J.L., et al., Whole genome sequencing confirms bacterial foodborne illness in pets that ate contaminated raw pet food. J Vet Diagn Invest. 2019 Mar; 31(2):235-240.

Jones J.L., et al., Information for veterinarians on reporting suspected animal food issues. J Am Vet Med Assoc, 2018. 253 (5): p. 550-553.

Du, X., et al., Intra-laboratory Development and Evaluation of a Quantitative Method for Measurement of Aflatoxins B1, M1 and Q1 in Animal Urine by High Performance Liquid Chromatography with Fluorescence Detection. J Anal Toxicol, 2017. 41(8): p. 698-707.

Smith, L.L., et al., Development and Validation of Quantitative Ultraperformance Liquid Chromatography–Tandem Mass Spectrometry Assay for Anticoagulant Rodenticides in Liver. Journal of Agricultural and Food Chemistry, 2017. 65(31): p. 6682-6691.

Reimschuessel, R., et al., Multilaboratory Survey To Evaluate Salmonella Prevalence in Diarrheic and Nondiarrheic Dogs and Cats in the United States between 2012 and 2014. J Clin Microbiol, 2017. 55(5): p. 1350-1368.

Mitchell E., et al. Pathology and Epidemiology of Oxalate Nephrosis in Cheetahs. Journal of Veterinary Pathology. 2017. 54(6):977-985.

Leahy, A.M., et al., Faecal Campylobacter shedding among dogs in animal shelters across Texas. Zoonoses Public Health, 2017. 64(8): p. 623-627.

Shao, D., et al., Intralaboratory development and evaluation of a high-performance liquid chromatography-fluorescence method for detection and quantitation of aflatoxins M1, B1, B2, G1, and G2 in animal liver. J Vet Diagn Invest, 2016. 28(6): p. 646-655.

Goodman, L.B., et al., High-throughput Detection of Respiratory Pathogens in Animal Specimens by Nanoscale PCR. Journal of Visualized Experiments: JoVE, 2016(117): p. 54781.
Tkachenko A., et al. Investigation of melamine and cyanuric acid deposition in pig tissues using LC-MS/MS methods. Food and Chemical Toxicology. 2015. 80:310-318.

Nemser SM., et al. Investigation of Listeria, Salmonella, and Toxigenic Escherichia coli in Various Pet Foods. Foodborne Pathogens and Disease. May 2014.

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