A new COVID-19 vaccine has been developed by scientists that can be given only in one dose via the nose. The vaccine has been found to be effective in the trial conducted on mice susceptible to the coronavirus. It has been developed by inserting the virus’ spike protein (through which coronavirus enters body cells) inside adenovirus, a virus that causes the common cold. Adenovirus was tweaked or modified in a way that it lost potential to cause illness.
The modified adenovirus acts as a carrier of the spike protein and generates an immune response against the virus. The study on this new vaccine has been published in the journal Cell.
According to the study, “The one delivered via the nose targets the initial site of infection, and causes more widespread immune response.”
The vaccine given via the nasal delivery route has been found to provide a strong immune response throughout the body and particularly in the nose and respiratory tract. The scientists will soon conduct nonhuman primates and human trials to test its effectiveness and safety.
Senior author Michael S. Diamond from the Washington University School of Medicine said, “We were happily surprised to see a strong immune response in the cells of the inner lining of the nose and upper airway and profound protection from infection with this virus”.
Diamond added, “These mice were well protected from disease. And in some of the mice, we saw evidence of sterilising immunity, where there is no sign of infection whatsoever after the mouse is challenged with the virus”.
When the vaccine is injected into the muscles, the immune response it generates only prevents pneumonia and not the infection in the nose and lungs. While the vaccine, when given via nasal delivery route, prevents the infection in both the nose and lungs. The study findings suggest that individuals vaccinated via nasal route would not develop infection elsewhere in the body.