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SAVE 46 % OFFTHE NEWSSTAND RATE SUBSCRIBE ONLINE: tsoffers.ca/deal/comm OR CALL: 416-367-4500 and quote code 2DAYSAVE for weekend home delivery for 12 months COVID-19 vaccine uptake in Ontario has been high this spring and summer, with more than 60 per cent of residents now fully vaccinated. However, some people remain on the fence, mulling over ques- tions that leave room for doubt about vaccine safety and efficacy. One of those questions is how mRNA vaccines like the ones Pfizer and Moderna produce could be developed so quickly and still be safe and effective. To help clear up confusion, Bill Anderson, professor emeri- tus in chemical engineering at the University of Waterloo, an- swers this question and a few oth- ers. FIRST, HOW DO mRNA VACCINES WORK? Before getting in- to how the mRNA vaccines are devel- oped, it's helpful to know how they work. mRNA vac- cines use ribonucleic acid (RNA), a molecule similar to DNA, to teach our cells how to mount an immune response against SARS- CoV-2 without using the live vi- rus. Messenger RNA (mRNA) is a molecule that gives cells instruc- tions for making a protein like the one found on the surface of the virus. When a person receives the vaccine, their cells read the genetic instructions like a blue- print, produce the protein found on SARS-CoV-2 and toss out the blueprint. The cells then display the pro- tein on their surface, triggering an immune response and the pro- duction of antibodies the body can use to fight the actual virus if it enters in the future. "The mRNA vaccine itself is simply the mRNA blueprint ma- terial held within a nanoparticle package, which serves two im- portant functions," Anderson said. "It protects the mRNA, since it is quickly and easily destroyed in the body, and it helps the mRNA get into your cells, where the blueprint gets read and the vi- ral fragments are constructed." Q: HOW WERE mRNA VAC- CINES FOR COVID-19 DEVEL- OPED SO QUICKLY? A: While mRNA COVID-19 vaccines are new, Anderson said there is a long history of develop- ment behind the platform used to produce them. Scientists con- firmed the existence of mRNA in cells in 1961 and successfully in- jected synthetic mRNA into an animal for the first time in 1990. Moderna Therapeutics, one of the COVID-19 vaccine developers, was founded around commercial- izing mRNA technologies for in- fectious diseases and cancer in 2010. Additionally, Google Scholar lists more than 250,000 research papers mentioning "mRNA vac- cines" prior to 2020. "So, in some ways, this vaccine has decades of development work behind it," An- derson said. Because mRNA technology is a platform into which vaccine de- velopers can plug various blue- prints to target different diseas- es, some of the work to develop a vaccine for COVID-19 was done long before the first case of the vi- rus was ever detected. "Once the virus responsible for COVID-19 was identified and genetically sequenced, compa- nies just had to determine which part of the blueprint to use for the best effect," Anderson said. "Once that was done and tested, manufacturing could be quickly ramped up." Q: HOW IS mRNA VACCINE TECHNOLOGY DIFFERENT FROM OTHER TYPES OF VAC- CINES? A: Traditional vaccines, such as live-attenuated or inactivated vaccines, rely on growing and harvesting cells for further pro- cessing, as well as multiple puri- fication steps. This process can take days or weeks, is much hard- er to scale up for mass production and allows more room for issues in production, which can result in batches being discarded, An- derson explained. "The mRNA platform is great from a manufacturing point of view," he said. "It can essentially be done in a few hours with a mix- ture of known starting materials and some enzymes, followed by some purification and packaging -- all under pharmaceutical- grade manufacturing conditions, of course." Because of the quick and sim- ple method used to manufacture mRNA vaccines, producers such as Moderna and Pfizer have been able to manufacture hundreds of millions of doses in a matter of months. "From a development perspec- tive, the simplicity and rapidity of the mRNA platform is a key benefit," Anderson said. "As more production capacity is de- veloped and brought online, the response can accelerate further worldwide." NEWS An expert in chemical engineering digs into the history of mRNA vaccines. Steve Russell photo NERVOUS ABOUT PFIZER OR MODERNA VACCINES? READ THIS