UK researchers call for nasal spray vaccine to fortify protection against COVID-19 infection

Antibodies produced in the nose decline nine months after COVID-19 infection, while antibodies found in the blood last at least a year, a new study has found.

Antibodies in the nasal fluid, known as immunoglobulin A, or IgA, provide first-line defense against COVID-19 by blocking SARS-CoV-2 virus when it first enters the respiratory tract. These antibodies are very effective in preventing the virus from entering cells and causing infection.

However, the investigators found that the nasal antibodies were only present in those recently infected and were particularly short-lived against the Omicron variant, compared to earlier variants.

The research was led by teams from Imperial College London and the University of Liverpool.

Based on the study, the researchers have called for the next generation of vaccines to include nasal spray or inhaled vaccines that target these antibodies more effectively, which could potentially reduce infection and transmission.

Edits by EP News Bureau