COVID-19 has been infecting people around the world for more than two years. Many people still get the virus even though they have received as many as four vaccinations. Chiang Kuan-yu, a doctor of the Taipei City United Hospital in Taiwan, said that the “mucosal vaccine” given in the form of a nasal or oral spray can help activate immune cells in the respiratory tract and may be more effective in preventing infection than intramuscular (IM) vaccine injections.
The SARS-CoV-2 virus infects the mucosal surfaces of the nose and lungs and thus, the mucous producing surfaces are the first line of defense against pathogens.
