The CNN Health in a headline article writes with a sniff or a swallow, new vaccines aim to put the brakes on Covid-19 spread. The article argues that despite the fact that current mRNA-based Covid-19 vaccines are hugely successful saving almost 20 millions people globally, they have not been able to stop the Covid virus apreading and producing new variants worldwide.
“As the SARS-CoV-2 virus (Covid-19) spreads, it changes. That’s helped it get past our firewalls, the immunity created by vaccines or left behind after we recover from an infection. Which is why, well into the third year of the pandemic, we’re in the midst of another wave of Covid-19 caused by the most immune-evasive variant yet, BA.5. And more variants are coming,” writes the CNN.
Dr. Ellen Foxman, an immunobiologist at the Yale School of Medicine, told the CNN “The hope is to shore up the defenses right there in the nose so that the virus can’t even replicate in the nose. And then someone who has a really effective mucosal vaccination can’t even really support viral replication or make viruses that can infect other people. That would be like the holy grail.”
About nine existing vaccines reportedly work through mucosal lining including polio, cholera, salmonella & rotavirus, and nasal flu mist. “What hasn’t really happened with mucosal vaccines is kind of huge advances in technology that have happened with injectable vaccines, even before Covid,” Ed Lavelle, an immunologist at Trinity College in Dublin told to CNN.
According to the CNN article, the mucosal vaccines may also target slightly different part of the immune system than the current Covid shots. “They might be a little more promiscuous in the way they recognize different variants. And that’s obviously a plus,” Jennifer Gommerman, an immunologist at the University of Toronto who specializes in tissue-specific immunity, told the CNN.
“Whether they’ll be able to confer complete sterilizing immunity, that’s a very tall order. But we should be now working on ways to slow down person-to-person transmission, because this virus continues to mutate and then fools our immune system and gets past that mucosal layer. This is now a very contagious virus,” Gommerman added.