Researchers investigate COVID-19 among high-risk food workers in Quebec and Ontario

Studies to evaluate optical detection and saliva antibody testing methods

MONTREAL, March 17, 2021 (GLOBE NEWSWIRE) — Throughout this pandemic, thousands of Canadians have had to continue working to provide essential services, such as in food production and packing plants, as well as in grocery stores, restaurants, and bars. At times, this has meant working in close proximity to colleagues and customers. The Government of Canada, through its COVID-19 Immunity Task Force (CITF), is providing approximately $4.5 million to support two studies looking at the impact of various aspects of COVID-19 on food industry workers in Quebec and Ontario.

Quebec Study

Over the next six months, researchers will follow approximately 450 people working in grocery stores, restaurants, and bars in the Quebec City and Chaudière-Appalaches regions. A group of 150 people working in hardware stores will also be studied for comparison purposes.

“Since the beginning of the pandemic, food service employees have been at high risk of exposure to COVID-19 due to their close daily contact with a large number of people,” explains Dr. Denis Boudreau, PhD, Professor, Faculty of Science and Engineering at Université Laval. “However, there are still limited data on how many of these workers have been exposed to the virus and what their immune responses are. Our study will attempt to shed light on these issues.”

Researchers will first collect blood samples to determine how many of these workers have antibodies to SARS-CoV-2, the virus that causes COVID-19, suggesting a previous infection, regardless of whether they had symptoms. Blood samples will be taken again after 12 and 24 weeks to determine how many become infected over the 6-month study period. After the first visit, participants eligible to receive the vaccine according to public health recommendations will be able to do so and will remain in the study.

In addition to traditional blood testing techniques, the researchers will use an optical detection method co-developed by researchers at the Université de Montréal and Université Laval. “This technology, called surface plasmon resonance spectroscopy, uses a light beam to detect antibodies to the virus captured on a thin metal film,” explains Dr. Boudreau, who is also a researcher at the Centre d’optique, photonique et laser (COPL) at Université Laval. “This technique makes it possible to quickly evaluate how well the immune response is working.”

The study also aims to better understand the immune response during a SARS-CoV-2 infection.

“More than 80% of people infected with SARS-CoV-2 don’t have severe COVID-19 symptoms, meaning their immune system is working. However, we still know little about this immune response,” explains Dr. Sylvie Trottier, MD, head of the clinical arm of the study, from the Faculty of Medicine at Université Laval and the Centre de recherche du CHU de Québec-Université Laval. “Our study will provide new clues about people’s immune response and factors that may contribute to developing a severe case of COVID-19.”

To facilitate participant recruitment, the project team is working with partners at the Fédération du commerce de la Confédération des syndicats nationaux (CSN) and the Association québécois de la quincaillerie et des matériaux de construction (AQMAT), which represent the majority of members in the food and hardware sector in Quebec.

Ontario Study

The Ontario study will focus on employees at several food production facilities, as well as on staff at some food retail outlets, such as cafés or restaurants within hospitals in the Greater Toronto Area.

“We are looking to better understand the transmission of SARS-CoV-2, by noting how often individuals at any one site get infected,” explains Dr. Amit Oza, MD, lead investigator at the University Health Network. “Understanding how the virus may be transmitted in occupations where physical distancing is challenging due to the nature of the job is important. It will help provide important new information on how transmission occurs and how to stop it. It will also help inform fast and widespread testing and tracing practices.”

The study is providing testing for COVID-19, whether or not people show signs and symptoms of the virus, in settings where the risk of infection is higher. “We will take blood samples at several time points. Closely examining repeat samples from participants will give us a clearer picture of how SARS-CoV-2 antibodies evolve over time and how this can influence transmission patterns and subsequently, public health interventions,” says Dr. Oza. “Screening for COVID-19 even in the absence of symptoms is critical to help curb transmission as early as possible.”

Employees who test positive for an active SARS-CoV-2 infection will be re-tested to confirm their infection. They, their employer, and their local public health authority will be notified so that infection control measures and appropriate care can be put in place. Those who test negative will have the opportunity to be retested several times so that researchers can study how many workers get infected over the course of the study.

“The advent of vaccination will allow us to assess the uptake of vaccination,” adds Dr. Oza. “Blood samples are being banked so that we can study the immune response in those who had SARS-CoV-2 infection, whether or not they receive a vaccine, once additional funding is secured.”

The Ontario food workers study that the CITF is funding is part of a larger project called “A Research Platform to Screen and Protect Individuals that Work Within a Food Production, Healthcare, Research or Clinical Organization (RESPECT)”.

“Both these studies are focusing on public-facing workers whose jobs require them to be on site, who are important to the nutrition of Canadians, and who are essential to Canada’s economy,” says Dr. Catherine Hankins, CITF Co-Chair.

“Workers in the food production, retail or service industry may be at higher risk of contracting COVID-19, either because they have direct contact with many members of the public and/or because of their work environment,” says Canada’s Chief Public Health Officer, Dr. Theresa Tam. “Although vaccination is underway, it remains critical that we continue to support research studies that will help better understand COVID-19 transmission, its impacts, and different immune responses.”

About the COVID-19 Immunity Task Force

In late April 2020, the Government of Canada established the COVID-19 Immunity Task Force with a two-year mandate. The Task Force is overseen by a Leadership Group of volunteers that includes leading Canadian scientists and experts from universities and healthcare facilities across Canada who are focused on understanding the nature of immunity arising from the novel coronavirus that causes COVID-19. To that end, the CITF is supporting numerous studies to determine the extent of SARS-CoV-2 infection in Canada (in the general population as well as in specific communities and priority populations), understand the nature of immunity following infection, develop improved antibody testing methods, and help monitor the effectiveness and safety of vaccines as they are rolled out across Canada. The Task Force and its Secretariat work closely with a range of partners, including governments, public health agencies, institutions, health organizations, research teams, other task forces, and engages communities and stakeholders. Most recently, the Task Force has been asked to support vaccine surveillance, effectiveness and safety as part of its overall objective to generate data and ideas that inform interventions aimed at slowing—and ultimately stopping—the spread of SARS-CoV-2 in Canada. For more information visit: www.covid19immunitytaskforce.ca.

Media contacts:

Université Laval
Jean-François Huppé
Cell: 418 656-7785
Email: jean-francois.huppe@dc.ulaval.ca

Princess Margaret Cancer Centre, UHN
Alex Radkewycz
Cell: 416-918-7313
Email: Alexandra.Radkewycz@uhn.ca

COVID-19 Immunity Task Force
media@covid19immunitytaskforce.ca
Rebecca Burns, Cell: +1.438.871.8763
Caroline Phaneuf, Cell: +1.514.444.4532