More than three years after the start of the COVID-19 pandemic, the SARS-CoV-2 virus continues to surprise scientists.

For example, when McMaster University researchers Dawn Bowdish and Andrew Costa were studying vaccinated older adults in retirement and long-term care homes, they discovered that those who had been infected with Omicron BA.1-2 had a 30-fold higher risk of reinfection with the BA.5 variant a few months later. It was the opposite of predicted patterns.

Today in The Conversation Canada, Bowdish and Costa discuss these results and put them in context for fall 2023. While it’s not clear if the findings apply to other variants or broader populations, they do reinforce the importance of vaccination.

“What the findings do tell us is that older adults who have had a previous COVID-19 infection shouldn’t rely on that to protect them against reinfection this fall. To protect against severe illness, keeping booster shots up to date is recommended.”

Also today:

Patricia Nicholson

Health + Medicine Editor

Researchers found a surprising twist in a study of Omicron infection in older adults. The new information highlights the importance of COVID-19 vaccine booster shots. (Shutterstock)

COVID-19 vaccine boosters are the best defence: Older adults shouldn’t rely on previous infection for immunity

Dawn ME Bowdish, McMaster University; Andrew Costa, McMaster University

We still have much to learn about many aspects of COVID-19 — including its lingering health effects and the mechanics of its endless mutations — but we do know one thing: we can’t let our guard down.

While zuranolone represents an exciting advance in the treatment of postpartum depression, many questions about its potential impact remain unanswered. (Shutterstock)

Zuranolone for postpartum depression: Hope, hype or both?

Ryan Van Lieshout, McMaster University

Amid the fanfare about a new medication for postpartum depression, it’s important to remember that PPD is underdiagnosed and undertreated, and that safe and effective treatments already exist.

America’s overnight summer star, country singer Oliver Anthony, performs in Moyock, N.C., on Aug. 19. (Kendall Warner/The Virginian-Pilot via AP)

How this summer’s hit ‘Rich Men North of Richmond’ was appropriated by both the right and left

Frédérick Guillaume Dufour, Université du Québec à Montréal (UQAM); Alexis Harton, Université du Québec à Montréal (UQAM)

Although its content is essentially libertarian, the No. 1 song of the summer in the U.S. resonates with both some Democratic supporters and those on the Trumpist right.

Analyzing samples of polar bears can reveal not only what they ate but also the food web during their lives. Polar bears pictured live in captivity. (AP Photo/Ronald Zak)

How analyzing ancient and modern polar bear samples reveals the full scope of global warming

Jennifer Routledge, Trent University

Comparison of modern and archaeological polar bears indicates that four millennia of food web stability has been disrupted by modern climate change.

La Conversation Canada

Les enseignants et professeurs de sciences et de mathématiques ne sont pas à l'abri des enjeux pédagogiques qui découlent du déferlement de la récente vague d'IA. (Patrick Charland), Image générée sur

ChatGPT, allié ou adversaire pour l’enseignement des sciences et des mathématiques ?

Patrick Charland, Université du Québec à Montréal (UQAM); Hugo G. Lapierre, Université de Montréal; Pierre-Majorique Léger, HEC Montréal

L’utilisation de ChatGPT en milieu scolaire ne représente pas uniquement un enjeu pour l’enseignement du français. Les enseignants de sciences et de mathématiques doivent également s’y adapter.