Scientists are working on COVID vaccines delivered through nasal sprays that could stop the coronavirus from invading the body at its most common entry point, the mucous membrane of the nose and throat.
More than a dozen clinical trials with nasal sprays are under way, The Guardian reported.
USA Today said Vietnam, Thailand, Brazil, and Mexico have already started manufacturing the nasal vaccine in anticipation of success in the clinical trials.
A nasal vaccine would probably be employed as a booster in the United States but might be widely used in less-developed parts of the world where injectable vaccines are not common, USA Today reported.
While injectable vaccines help the body ward off severe illness, nasal vaccines could stop the virus from entering the body in the first place. The effectiveness of injectable vaccines wanes over time, and COVID variants can evade the vaccines, as evidenced by the high number of Omicron cases.
"If you think of your body as a castle, an intramuscular vaccination is really protecting the inner areas of your castle so once invaders come in, that immunity protects against them taking the throne," Sean Liu, MD, medical director of the Covid clinical trials unit at the Icahn School of Medicine at Mount Sinai in New York City, told
