At present, over 170 COVID-19 vaccine candidates are at various stages of development. And with increasing numbers of COVID-19 patients across the globe, an intranasal vaccine can be instrumental in tackling the situation.
The intranasal vaccine (Ad-Covid), which contains a weakened flu virus with some coronavirus genes, was the first COVID-19 nasal spray vaccine candidate to enter human clinical trials in September. It is expected to benefit from mucosal immunity in the nasal passages elicited by the intranasal application of the vaccine.
There are many advantages of the intranasal route over the traditional muscular stick. The Ad-Covid induces mucosal immunity that can erase the virus in the nasal cavity. On the other hand, a traditional intramuscular vaccine cannot kill the virus in the nasal cavity. So the virus replicates in the upper respiratory tracts. This is the reason why the intranasal vaccine is more effective as it stimulates the body’s mucosal immunity.
Intramuscular vaccines, on the contrary, require an experienced healthcare worker, syringes and the vaccine all at the same place at the same time, making for a logistical nightmare.
Also, intramuscular vaccines may require two doses as opposed to one dose of pre-filled syringe vaccine which is administered right in the nose. It could be self-administered too. These logistical factors loom even longer in developing nations with lesser infrastructure. When compared to the intramuscular vaccine, healthcare workers may take years to cover the whole population.
To solve the problems, the NASO VAX influenza intranasal vaccine stimulates mucosal and cellular response producing robust SERUM and mucosal antibody response.
If researches continue in this direction, intranasal delivery could just be the vehicle by which COVID-19 may be finally vanquished.
