Photo courtesy of CDC

Section Chiefs:  

Dr. Nicole Aulik (Bacteriology/Serology);

Dr. Ailam Lim (Molecular)

Bacteriology Supervisor: 

Beth Angell

Molecular Supervisor:

Jennifer Cooper

Serology Supervisor:

Melissa Lund

Section E-mail:


Photo courtesy of Hoard’s

Informational Salmonella Handouts

A project by The Ohio State University and University of Wisconsin-Madison, funded through CDC’s Antibiotic Resistance Solutions Initiative

Additional Links (Wisconsin Department of Health Services) (UW-Extension)

Recent Articles …

WVDL Collaborates with Others to Publish ‘Genome Divergence and Increase Virulence of Outbreak Associated Salmonella enterica subspecies enterica serovar Heidelberg’ in Gut Pathogens

(Posted January of 2019)

The WVDL continues to see multi-drug resistant (MDR) Salmonella enterica subspecies enterica serotype/serovar Heidelberg infections in dairy beef calves and more recently beef steers and cows. To better understand this Salmonella isolate, the WVDL collaborated with researchers at South Dakota State University (SDSU) and the SDSU Veterinary Diagnostic Laboratory. Whole genome based single nucleotide polymorphism based analysis of the isolates from the 2015 and 2016 multi-state outbreak of Salmonella ser. Heidelberg which also had human cases confirmed in fifteen different states were analyzed. It is believed the majority of human cases were caused by direct contact with dairy beef calves that were sick with active Salmonella ser. Heidelberg infection. Traditionally, Salmonella ser. Heidelberg was predominately a Salmonella serovar adapted to poultry.  This publication defines the relatedness of the Salmonella ser. Heidelberg strains collected from many different hosts and also examined both virulence and antibiotic resistance genes. The 2015-2016 outbreak isolates did cluster together and were highly related.  As compared to older Salmonella ser. Heidelberg isolates, the outbreak-associated strain had more antibiotic resistance genes and contained Salmonella atypical fimbriae (Saf) genes that were absent in other Salmonella ser. Heidelberg strains, which may have contributed to the increased disease severity of these strains in both humans and calves.

The publication can be found at:
Genome Divergence and Increase Virulence of Outbreak Associated Salmonella enterica subspecies enterica serovar Heidelberg

New human cases of Salmonellosis caused by Multidrug Resistant (MDR) Salmonella ser. Heidelberg since December 2017

(Posted July 20, 2018)

As the weather warms, there has been an increase in bovine cases of MDR Salmonella enterica subspecies enterica serotype/serovars Heidelberg.  In addition, the CDC has reopened their investigation into the multidrug resistant Salmonella ser. Heidelberg due to new human cases. Since December 2017, the WVDL has isolated this MDR Salmonella ser. Heidelberg strain 10 times from bovine fecal or tissues samples. This is a gross under-representation of the amount of disease. From these isolates and isolates from previous years, we have noticed a regional difference between the two dominate PFGE patterns.  The JF6X01.0523 strain is most commonly associated with the Midwest or animals originating from the Midwest.  This strain is the more virulent strain and more common, whereas the JF6X01.0590 strain resides in the southeast and has demonstrated less mortality.  There is ongoing research to understand the virulence differences between these two PFGE patterns as they both contain the same MDR genes.  The WVDL continues to work with our state and federal counterparts to understand this outbreak, which has been occurring since 2015.

Low Temperatures and Negative Energy Balance in Calves

(Posted Jan. 22, 2018)

Cold weather has arrived in the upper Midwest. Calf raisers know that cold temperatures increase the calf’s maintenance requirements for energy, but many do not know that the maintenance requirements also increase for protein and fat-soluble vitamins if the calf is ill from conditions like scours and pneumonia. Optimizing nutrition of sick calves can make the difference between a dead and a healthy calf.  Read More …

Update on MDR Salmonella serotype Heidelberg Case Count

(Posted Dec. 22, 2017)

The WVDL and our state and federal collaborators would like to remind veterinarians and producers to use caution when working with animals with confirmed or suspected multidrug resistant (MDR) Salmonella enterica subspecies enterica serotype Heidelberg.   Read More …

New human cases of Salmonellosis caused by Multi-drug Resistant (MDR) Salmonella Heidelberg spark re-opening of outbreak investigation

(Posted Aug. 13, 2017)

A multi-state outbreak investigation that began in July 2016 after a 16-year-old boy became ill after buying calves for a 4-H project has been re-opened by the Centers for Disease Control and Prevention (CDC). As of August 2, 2017 there have been 46 confirmed human cases of MDR Salmonella enterica subspecies enterica serotype Heidelberg reported to the CDC and other local health officials, with ten of these cases reported since April 2017.  Read More …