Sample types for early detection of Mycoplasma hyopneumoniaeis a popular post on this blog. Dr. Pieters, head of the MycoLAb at the University of Minnesota created an online quick guide to help swine practitioners decide which sample type they should collect if they are looking for Mycoplasma hyopneumoniae.
The emergence of antimicrobial resistance in humans, animals
and the environment is a major global public health threat to both human and
veterinary medicine. Efforts to address
this important issue involve government, industry, academia, and most notably,
veterinary diagnostic laboratories (VDLs).
These efforts include surveillance to assess the extent resistance in
human and animal pathogens and the development of policies to monitor and
control antimicrobial resistance.
A collaborative effort involving the stakeholders listed above is the key to addressing this emerging threat of antimicrobial resistance and VDLs play major roles in these collaborative efforts. As reported in a Commentary by GK Hendrix in the Journal of Veterinary Diagnostic Investigation in 2018, VDLs are the “nexus in the battle against antimicrobial resistance” (1). The University of Minnesota VDL Bacteriology Section performs almost 30,000 bacterial cultures annually, and most of the pathogenic isolates are archived for future use. These uses include further testing (subtyping, virulence gene assays, serotyping, etc.), use in disease control efforts (autogenous vaccines, etc.), various research projects, and surveillance studies. Almost 5,000 of these pathogenic bacteria are subjected to antimicrobial resistance testing annually, and these antimicrobial minimum inhibitory concentration data are archived for decades for further use.
For our part in this aforementioned collaborative effort in
antimicrobial stewardship, the University of Minnesota VDL is actively involved
in two collaborative government-organized antimicrobial resistance projects as
well as several collaborative academic research projects on antimicrobial
resistance. The common goal of the
collaborative government projects is to determine the population and
distribution of resistant bacteria in the U.S.
The first of these projects is the U.S. Department of Agriculture (USDA) Animal and Plant Health Inspection Service National Animal
Health Laboratory Network (NAHLN) project (2).
This project has 19 AAVLD-accredited laboratories throughout the U.S.
and Canada participating with the objective of monitoring antimicrobial
resistance profiles in animal pathogens routinely isolated from VDLs. Ultimately, this project will result in a national
centralized data collection and reporting process, using harmonized methods and
antimicrobial resistance interpretation and reporting standards. It aims to monitor data for trends in
antimicrobial resistance phenotypes (and eventually genotypes) by identifying
new or emerging resistance profiles, monitoring usefulness of antimicrobials
over time, and reporting these trends to facilitate antimicrobial stewardship
This USDA project
began in January, 2018, and initially involved collection of isolates and
antimicrobial resistance data from Escherischia
coli (all species), Salmonella
enterica (all species), Mannheimia
haemolytica (cattle) and Staphylococcus
intermedius group (companion animals) from routine VDL submissions. A target of about 3,000 isolates will be collected
from the participating VDLs annually and archived for further testing. The antimicrobial testing data will be
tracked and stored by USDA for each
isolate and an annual report will be prepared for stakeholders. This report will include antimicrobial
resistance trends for antibiotics important for human and animal health and the
distribution of minimum inhibitory concentrations for each antimicrobial
monitored for each bacterial pathogen for each animal species included in the
The second of these collaborative antimicrobial resistance projects
is the Food and Drug Administration
(FDA), Center for Veterinary
Medicine, Veterinary-Laboratory Investigation and Response Network (Vet-LIRN)
project (3). This project has 21 AAVLD-accredited laboratories participating
with the objective of performing surveillance of antimicrobial susceptibility
testing results and whole genome sequencing of pathogens from the National
Antimicrobial Resistance Monitoring System scope of interest (4).
This FDA project began in January, 2017, and initially involved collection of isolates and data for three zoonotic bacterial pathogens, with several other bacterial species added to the project in July, 2018. About 2,000 isolates have been collected since project inception, and the FDA has randomly selected about 200 of these isolates for whole genome sequencing. The remaining isolates have been archived for future studies. As an additional benefit related to this project, the University of Minnesota VDL received funds from FDA to purchase an Illumina iSeq Sequencer and participate in a collaborative project designed to increase the number and capabilities of network laboratories involved in the whole genome sequencing portion of this FDA project. Standardization and harmonization of these bacterial genome sequencing abilities among participating laboratories is further designed to increase the network capacity and facilitate future outbreak investigations.
In summary, in support of antimicrobial stewardship efforts, the University of Minnesota VDL Bacteriology Section provides clinical isolates and antimicrobial susceptibility testing data for two collaborative government-initiated projects, one in collaboration with the USDA and the other with the FDA. Further, the VDL as a whole provides leadership in antimicrobial stewardship on a daily basis, cooperating with disease outbreak investigations, collaborating with academic and industrial researchers, and educating veterinarians, clients and the public on issues of antimicrobial stewardship (1).
Today, we are very pleased to report that a new indirect ELISA to identify Senecavirus A antibodies has been validated at the University of Minnesota and is now available for our Veterinary Diagnostic Laboratory clients. This ELISA targets specifically antibodies against Viral Protein 2 (VP2) and has a sensitivity of 94.2% and a specificity of 89.7%. The test does not cross react with antibodies against Foot-and-Mouth Disease allowing for a quick differentiation between a Senecavirus A outbreak and a costly foreign animal disease.
Background: Senecavirus A (SVA), a member of the family Picornaviridae, genus Senecavirus, is a recently identified single-stranded RNA virus closely related to members of the Cardiovirus genus. SVA was originally identified as a cell culture contaminant and was not associated with disease until 2007 when it was first observed in pigs with Idiopathic Vesicular Disease (IVD). Vesicular disease is sporadically observed in swine, is not debilitating, but is significant due to its resemblance to foreign animal diseases, such as foot-and-mouth disease (FMD), whose presence would be economically devastating to the United States. IVD disrupts swine production until foreign animal diseases can be ruled out. Identification and characterization of SVA as a cause of IVD will help to quickly rule out infection by foreign animal diseases.
Methods: We have developed and characterized an indirect ELISA assay to specifically identify serum antibodies to SVA. Viral protein 1, 2 and 3 (VP1, VP2, VP3) were expressed, isolated, and purified from E. coli and used to coat plates for an indirect ELISA. Sera from pigs with and without IVD symptoms as well as a time course following animals from an infected farm, were analyzed to determine the antibody responses to VP1, VP2, and VP3.
Results: Antibody responses to VP2 were higher than VP1 and VP3 and showed high affinity binding on an avidity ELISA. ROC analysis of the SVA VP2 ELISA showed a sensitivity of 94.2% and a specificity of 89.7%. Compared to IFA, the quantitative ELISA showed an 89% agreement in negative samples and positive samples from 4–60 days after appearance of clinical signs. Immune sera positive for FMDV, encephalomyocarditis virus, and porcine epidemic diarrhea virus antibodies did not cross-react.
Conclusions: A simple ELISA based on detection of antibodies to SVA VP2 will help to differentially diagnose IVD due to SVA and rule out the presence of economically devastating foreign animal diseases.
The University of Minnesota highly values its partnerships with the industry stakeholders. With the objective to continue a fruitful and mutually beneficial collaboration, the College of Veterinary Medicine (CVM) and the College of Food, Agricultural and Natural Resource Sciences (CFANS) at the University of Minnesota hosted the Minnesota Pork Board (MPB) Research Committee on December 15th, to exchange ideas and to discuss projects that would be the most beneficial for the swine industry in Minnesota.
After a review of the current and future swine projects happening at both Colleges, Dean Ames (CVM), and Dean Buhr (CFANS) gave an update on the new facilities being built on the St. Paul Campus including the new animal isolation units that will allow our scientists to perform cutting edge research on infectious diseases.
Lastly, the MPB research committee toured the newly remodeled Food Centric Corridor Infectious Disease Research Laboratory as well as the Veterinary Diagnostic Laboratory.
The U of MN would like to thank all the representatives from the Minnesota Pork Board who came to meet our researchers and made this day the great success it was.
Presentation from the swine researchers
Visit of the Veterinary Diagnostic Laboratory with Dr. Torrison
The new animal isolation unit
Interdisciplinary research to address grand challenges related to food animals, primarily swine
The Minnesota State Fair closed its doors a week ago and once again the Miracle of Birth Center has been a huge success. This attraction, one of the visitors favorite displays cows, sows, does, goats, and hens giving birth and caring for their offspring. Animals are selected based on their estimated delivery date so that at least one birthing happens every day during the Fair.
Drs. Matt Sturos, Jerry Torrison, Alex Bianco, Bob Morrison, Fabio Vannucci, Maria Pieters, and Perle Boyer, faculty members from the swine group at the College of Veterinary Medicine, University of Minnesota as well as Drs. Megan Thompson, Nathan Winkelman, Abigail Redalen and Michael Strobel, professionals from the pork industry volunteered their time and shared their knowledge and expertise with the Minnesotans in order to increase awareness on what is actually happening on an American farm nowadays. Let’s also not forget the great participation of our graduate students, Drs. Talita Resende, Catalina Picasso, Luiza Roos, Jorge Garrido, Michael Rahe, and Fernando Leite.
Among the thousands of visitors admiring new-born calves and piglets, the Miracle of Birth Center had the honor of receiving the visit of the President of the University of Minnesota.
The Miracle of Birth Center has the very noble mission to educate people about modern farm production and we wish it many more successful years!