Could delivering Covid-19 immunity directly to the nose -- the area of the body via which it is most likely to be transmitted -- help conquer the pandemic?
The World Health Organization says clinical trials are underway to evaluate eight nasal spray vaccines that target Covid-19.
"When the virus infects someone it usually gets in through the nose," said researcher Nathalie Mielcarek who is working with the Lille Pasteur Institute to develop a nasal spray vaccine against whooping cough.
An article published in Scientific American in March urged developing nasal spray vaccines because they have an immediate effect on the virus in an infected person's mucus.
"This overwhelming response, called sterilising immunity, reduces the chance that people will pass on the virus," said the article.
Stimulating immunity directly in the nose "lowers the risk of infecting other people", said Mielcarek.
An article published in March by Gavi the Vaccine Alliance noted other advantages, including the fact that the sprays don't need refrigeration and don't need to be administered by health professionals.
In one of the couple's last YouTube videos, Dusty Graham said the COVID vaccine was "technically not" a vaccine.
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