As the SARS-CoV-2 virus 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.Even as vaccine manufacturers race to update the first-generation shots in the hopes of patching up our protection for the fall, other scientists are taking a different approach, making vaccines delivered via nasal sprays or tablets that would deploy more immune defenders to the body’s front lines: the lining of the mouth, nose and throat. “The hope is to shore up the defenses right there in the nose so that the virus can’t even replicate in the nose,” said Dr. Ellen Foxman, an immunobiologist at the Yale School of Medicine. “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,” said Foxman, who helped plan the International Congress of Mucosal Immunology Most are based on the oldest types of vaccine technologies, using killed or weakened versions of a virus or bacteria to teach the body how to recognize it and fight it off when a real infection gets underway. Because of those actual pathogens, some people can’t use these kind of vaccines. It’s risky to expose certain groups — including pregnant women and those with weakened immune systems — to even weakened viruses.None has achieved the goal of blocking the transmission of an infection, but that may be because they haven’t gotten the sam …
With a sniff or a swallow, new vaccines aim to put the brakes on Covid-19 spread – CNN
