Dr. Stefanie Czub is Canada’s BSE watchdog

Dr. Stefanie Czub is Canada’s BSE watchdog

Growing up in a small village of Hesse, Germany just north of Frankfurt and surrounded by agriculture, Stefanie Czub’s days were filled with adventure. Her parents were the local veterinarians and she often accompanied them as they made their daily rounds. Her favorite farmer raised horses and he had the best open-faced sandwiches.

“I regularly played with groups of children and we mostly ran barefoot. My favorite thing was to put my bare feet in a fresh pile of cow shit and feel it squish through my toes,” remembers Czub with a chuckle.  

“Little did I realize then, as an adult, I would be one of the ones called upon in Canada when the shit hit the fan.”

Many years later Dr. Stefanie Czub would become one of the faces alongside Canada’s chief veterinary officer Dr. Brian Evans when the announcement was made in May of 2003 that Canada had uncovered a case of home grown mad cow disease.

How did she get here?

While Stefanie’s parents did not initially agree with her choice to enter Vet College in Berlin, she believed it was her calling. But from there, the travel plans were somewhat clouded.

“My mother grew up in Berlin and my grandmother continued to live there. I once thought I would become a small animal veterinarian and worked in a small animal hospital for a couple of years after obtaining my vet degree,” says Czub bringing us into the entrance of her academic journey.

“But fate stepped in when one of my virology professors stopped me in the college parking lot and challenged me to change the focus of my PhD to from pharmacology to virology and pathology. It was standard in those days to get a PhD and since I had a curious nature, that academic path especially in pathology seemed to fit the bill.”

After finishing her PhD, Czub and her then husband Markus, a fellow veterinarian and virologist, received Fulbright stipends and worked as post-doctorates in Hamilton, Montana. The Rocky Mountain Laboratory was a fertile learning ground for the young scientist. It houses the federal lab of the National Institute of Health (NIH) focusing on infectious diseases, including prion diseases.

Czub recalls those years as the best of her life as the lab was nestled in the Rocky Mountains and she was again surrounded by nature and incredible people. Her scientific work at the lab provided a strong base for what would become her life’s work.

After a 10-year work-related interval back in Germany, the couple found themselves back in North America and settled in Winnipeg, Manitoba. Stefanie had accepted a job with the Canadian Food Inspection Agency (CFIA) putting her on the front lines of the puzzling world of Bovine Spongiform Encephalopathy or BSE. Part of her responsibilities included being the gatekeeper of the BSE reference lab.

“In 2001, before I left Germany, there was the first case of BSE in that country and general meat consumption dropped to 10 percent. I was called upon to do a lot of public education about the disease. It created enormous interest around the world and for me, the CFIA job posting for Winnipeg seemed another act of fate,” says Czub.

“My job in Winnipeg was to ensure that all the BSE tests were in place and everyone was trained in the event of an occurrence. Then it happened. On Saturday of the long weekend in May of 2003, I received a call from my friend and colleague Dr. Brian Miller from the provincial lab in Edmonton. He found something that wasn’t quite right and he wanted to courier a tissue sample right away.”  

A private plane brought the tissue sample to the Winnipeg lab and it was hand delivered to Czub by CFIA district veterinarian Dr. Kevin Millar.

Czub remembers it as a rather lonely time. Being a long holiday weekend, there were no others in the large complex than her and her team and it was close to midnight before she realized that the slide containing the brain tissue of an Alberta beef cow was BSE. She knew, come morning, the discovery would be a game-changer for the beef industry.

Fast forward to 2006 and with the majority of Canada’s BSE cases originating in Alberta it just made sense to move the CFIA’s BSE lab to Lethbridge. Dr. Robert (Bob) Church, professor emeritus of Medical Biochemistry and Molecular Biology at the University of Calgary, was instrumental in persuading Dr. Czub to move to Alberta.

“Bob is a colleague, a friend and I am proud to say that he is my mentor. I never had a mentor before and the importance of his influence on my life and my work is huge. Now I make it part of my mission to share my knowledge and experience with others,” says Czub.

“The members of my best team in Winnipeg chose not to move but now I have another best team and they have worked tirelessly to set up the BSE reference and surveillance labs in this province. It is still the provincial and federal labs that do the initial BSE testing and it is the CFIA BSE reference lab in Lethbridge making the final confirmation. I am responsible for the virology groups here as well, but much of my research continues to be on BSE.”

 

QUICK BSE FACTS:

Canada has had 20 BSE cases in cattle born in this country. In addition, in 1993, BSE was found in a purebred beef cow which was imported from Great Britain in 1987. Of the 20 cases reported in Canada, 15 of them have been diagnosed in Alberta. The latest BSE case was found in 2015. In all cases, no part of the animal entered the human food supply or animal feed chain.

In 2003, a dairy cow, originating from an Alberta farm, was diagnosed with BSE in the U.S.

According to Alberta Agriculture Alberta’s food safety system is among the best in the world. Most beef comes from animals that are less than 30 months of age, before BSE is a problem.

In Canada, the prevalence of BSE is extremely low as SRM removal eliminates more than 99 percent of the BSE infectivity if the animal is infected.

The search for answers continues

Dr. Czub says that the research focus now is directed at atypical BSE. The classic case of BSE (or feed-related cases) is referred to as the “C-type”cases. In the two forms of atypical BSE, the infectious agent is separated by weight where the lower one is identified as “L” atypical and the higher cases are known as “H” atypical. Scientists still don’t know the causes of both atypical forms.

“Worldwide there are around 88 cases of atypical BSE. Canada has had an “L” and an “H” case. In our research, we have found that by infecting an animal with atypical H- and L-type BSE in the brain it continues to show up in the brain comparable to the classic or “C” cases of BSE,” says Czub.

Through feeding, we have put atypical BSE brain through the rumen of some animals and found only one animal in the group of three tested positive for BSE so far. The animal was much younger than C-type BSE cases at 11 months of age. But we will need to continue to wait and see.”

Dr. Czub is one of four BSE experts worldwide so named by the World Animal Health Organization or OIE and she is called upon to do a lot of training around the world.

Here at home, she is concerned that although our rating for the disease is “Controlled Risk”, we may fall behind because we are not hitting our assigned target numbers per province for testing the four “d” animals (diseased, down, distressed, dead).  

“Our target BSE testing numbers for Alberta are 10,124 annually and for Saskatchewan it’s 7,586. Last year, we fell short and tested 27,604 animals, this is eight percent less than the target number of 30,000 for all of Canada,” says Czub.  

“Although the CFIA continues to very actively support the BSE surveillance program in terms of financial support to all BSE testing labs in Canada, I believe the biggest blow to achieving our goals was when the financial support from the province was removed for the farmer. The drop in test numbers needs to be closely monitored as it could impact our rating if it continues.”

“We want to achieve negligible risk status with the World Animal Health Organization (OIE), which is the best category for a country and we were ready to apply for that in 2016. The recent case of BSE found in Alberta now pushed that possibility to 2020. The infected animal was born in 2009 and we must wait 11 years for an upgrade to a better rating.”

By Bonnie Warnyca


 

Following the thousands of BSE cases in the United Kingdom it was clear that the disease came from contaminated feed. Research indicated that the only risk factor for the spread of BSE was through feeding cattle meat and bone meal (MBM) derived BSE-infected cattle. When a BSE case first showed up in Alberta in 1993, it was an animal imported from the U.K.

Canada put in place a number of mitigation measures to prevent infected material entering the feed chain, such as the enhanced feed ban, which eliminated the possibility for any BSE prion to be incorporated in any animal feed, including pet food and fertilizers.

In July 2003, Canada implemented the removal of the nervous tissue, or Specified Risk Material (SRM) from the human food chain. SRMs are tissues that, in BSE-infected cattle, contain more than 99 percent of BSE infectivity, and include brain, spinal cord, trigeminal and dorsal root ganglia, eyes, tonsils in animals over 30 months of age and the intestine in cattle of all ages.

Canada is not alone in finding BSE. Other countries to have native cases include the U.K., Germany, France, Portugal, Denmark, Spain, Italy, Switzerland, the Netherlands, Finland, Greece, Belgium, Austria, Czech Republic, Ireland, Israel, Liechtenstein, Slovakia, Slovenia, Luxembourg and Japan

by Bonnie Warnyca