Scientists in the United States have developed a vaccine against COVID-19 that can be given in one dose via the nose and is effective in preventing infection in mice susceptible to the novel coronavirus, an advance that may lead to protective candidates that can curb the pandemic.

The researchers will now try to test the vaccine in non-human primates and then eventually on humans to gauge the effectiveness of the vaccine to combat the virus, according to Washington University School of Medicine which published its findings in medical journal Cell.

According to the researchers, including those from the Washington University School of Medicine in the US, the nasal delivery route created a strong immune response throughout the body, but it was particularly effective in the nose and respiratory tract, preventing the infection from taking hold in the body.

They plan to test the vaccine in nonhuman primates and humans to see if it is safe and effective in preventing COVID-19 infection.

"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," said study senior author Michael S. Diamond from the Washington University School of Medicine.

"These mice were well protected from disease. And in some of the mice, we saw evidence of sterilizing immunity, where there is no sign of infection whatsoever after the mouse is challenged with the virus," Diamond said.

The global death toll from the new coronavirus has surpassed 800,000 with several European countries which were initially hit the virus experiencing new infection levels. South Korea has announced new measures as the virus continued to spread in the country after it was controlled earlier.

Latin America has become the hardest hit region with the virus even as the United States has reported over 176,000 cases and over 5 million infection cases. 

Source: Agencies