By Jana Manolakos
In 1906, Toronto’s SickKids hospital began seeing an alarming number of infants and young children with intense, barking coughs – signs of the first-known pertussis (“whooping cough”) epidemic in Canada. By the following year, it had killed 214 children in Ontario, 141 of them under 12 months old. Highly contagious and endemic, even today the disease is the second most common infectious childhood disease in Canada, after influenza.
In 1900, the team of Jules Bordet and Octave Gengou, at the Pasteur Institute in Brussels, had identified the Bordetella pertussis bacterium as the cause of the disease. Gengou went on to develop the first vaccine in 1912, and by 1914 it was being produced in several European and U.S. labs. The Ontario Provincial Laboratory and then Connaught Laboratories followed suit by 1919 with their pertussis vaccine, a Canadian first.
By 1937, continued international research into the disease had inspired scientists at Connaught and SickKids to develop an even more effective vaccine. Vaccine production at Connaught improved in the 1940s with the application of a fluid culture medium in experiments and the application of larger-scale production methods. These same methods were used by researchers at Connaught in the production of the Salk polio vaccine, which debuted in 1955 and catapulted Canada forward as the first country to eliminate polio. Research initiatives over the 1940s and ’50s resulted in Connaught taking the global lead in a new generation of combined vaccines that included diptheria, pertussis, tetanus and polio.
In Canada, developing, testing and finally approving a vaccine can take up to a decade or more. Initial animal testing may run over several years, followed by three phases of clinical trials in successively larger groups of people, often with hundreds and thousands of participating volunteers by the third phase. When all phases of the clinical trials have been successfully completed, the vaccine must meet Canadian licensing standards before it can be considered for approval by Health Canada’s Biologics and Genetic Therapies Directorate. The directorate also supervises all aspects of vaccine production and quality control throughout the vaccine’s lifecycle, to ensure that it is safe and effective.
Understanding the rigours of Canada’s vaccine approval process makes today’s rapid pace of developing a COVID-19 vaccine so much more impressive. Dr. Supriya Sharma, the chief medical advisor at Health Canada, says that to speed the process up, Health Canada is trying to get the regulatory process done in tandem with the final trials. She underscores, “The ultimate length of the review depends on the data.”