Saturday, November 21, 2020

Development of polio vaccine has useful parallels for COVID-19: historian

UVic historian Mitchell Hammond studies epidemics and the development of various vaccines

CBC News · Posted: Nov 21, 2020 
Medical researcher Dr. Jonas Salk studies slides in his laboratory, following the invention of his pioneering polio vaccine, circa 1957. 
(Three Lions/Hulton Archive/Getty Images)

As hopes rise for a COVID-19 vaccine, this isn't the first time millions of people have watched and waited for scientists and medical experts to develop such protection.

Historian Mitchell Hammond studies epidemics and the development of various vaccines at the University of Victoria and says there are parallels between today and the research done to develop a vaccine for polio.

"This was a disease that was feared in the first half of the 20th century. It's actually interesting that sort of like COVID today, polio was more severe in more developed countries," Hammond said on CBC's On The Island.

Polio is a viral disease that largely affected children under five years of age. In severe cases, the disease caused paralysis, trouble breathing and sometimes, death.

Developing the vaccine was something that researchers started on very early in the 1910s, Hammond said, even before the microbe had been isolated.

"They were experimenting with monkeys which was the closest analog that they could find as an animal model. But there wasn't much success with vaccine research until the late 1940s," he said.

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Eventually, a team led by Jonas Salk had a breakthrough with a vaccine in the mid 1950s. Another team led by Albert Sabin developed another successful vaccine in the early 1960s.

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However, there were setbacks.

The Cutter Incident — where the vaccine was prepared incorrectly by the Cutter pharmaceutical company and ended up infecting 40,000 children with polio and killing 10 — slowed down vaccination efforts.

Eventually, however, vaccination led to a point where polio is no longer a major danger in Canada. According to the Canadian Medical Association Journal, the last recorded case of wild poliovirus infection in Canada was in 1977.

"The combination of these two vaccines together really almost completely eradicated polio, certainly eliminated it from developed countries to the situation that we're in now where it just exists in a few pockets around the world," said Hammond.

A staff member sets up an antibody production line at the Ibex building of Lonza, where the Moderna mRNA coronavirus disease (COVID-19) vaccine will be produced, in Visp, Switzerland, Sept. 29, 2020. (Denis Balibouse/Reuters)

Hammond says the world of 2020 is very different from the mid-century. For one, scientists are able to work with the latest technologies at a much more rapid pace.

So far, there have been promising results from Pfizer and its German partner BioNTech, as well as Moderna. Russia's Sputnik V is also moving to advanced trials.There are at least 50 different vaccines at the human clinical trial stage around the world.

This crowded field of research brings its own challenges, says Hammond.

"Now, we face a situation where trust in scientists and scientific institutions is not quite the same as it was in the 50s and 60s and just hearing about competition and having vaccine development cast in a kind of race for prestige and profit, this is something that is certainly amplified when you have so many different corporate entities and governments that are pursuing this for different reasons," he said.

In addition, he says, the real test with the vaccine will come down to distribution to the most vulnerable members of the population.

"We've got to imagine rolling up our sleeves, not just for the vaccine but the team effort required."

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Listen to the interview with Professor Mitchelle Hammond on CBC's On The Island:

 A historical take on COVID and the race for a vaccine - Hear from a UVic History professor about polio, smallpox, and other past responses to medical emergency Gregor Craigie spoke with Mitchell Hammond, an assistant professor of History at University of Victoria who's studies epidemics and the development of various vaccines. 9:23 https://www.cbc.ca/news/canada/british-columbia/history-of-vaccines-1.5807401?cmp=rss

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