In a new fight against coronavirus, the Drugs Controller of India (DGCI) on Friday approved the trials intranasal booster doses manufactured by Bharat Biotech, the maker of Covaxin. The two trials approved by the DGCI will be carried out on volunteers, who will be given the booster as stand-alone two doses and as booster doses to those who have already received the Covaxin and Covishield.
What is the intranasal booster doses?
The intranasal vaccines will be given by spraying them inside the nose and the person will inhale it. Vaccines, since history, have always been jabbed into the muscle. All the approved Covid-19 vaccines, to date, have been injected into the upper arm. However, intranasal vaccines will act differently.
As studies have proved that several viruses including the intranasal booster doses, enter the body through the nose or any mucosa -- that lines up the nose, mouth, lungs and digestive tract. Once the virus enters, this wet tissue triggers a unique immune response from cells and molecules. Booster doses jabbed through muscles, fail to activate these mucosa cells and instead, it activates the immune cells from other parts of the body to fight Covid-19.
Hence, experts believe that the intranasal covid booster will be more effective in rooting out the virus from the moment it tries to enter the nasal organ.
How will the vaccine work?
Vaccines trigger a response in the blood. The response in the blood activated the B cells to release antibodies -- particularly IgG -- that roam in the body to find the virus. Other cells, including T cells, would either help B cells to produce antibodies or destroy the infected cells on their own.
Another added advantage of intranasal vaccines is, they activate the B cells of the mucosal tissues, which produce IgA, which largely destroys the air pathogens. Similarly, the T cells residing closeby, once identify the virus and stay alert, for the entire lifetime, to scout and destroy the same.
Will it reduce costs and ramp up the vaccination drive?
Experts say a yes. Given the easiness of its use, medical practitioners believe that this new vaccine can cover a larger population at a lesser time, hence, boosting up immunity against the virus. On the other hand, with the intranasal vaccine, the cost of the syringe and other equipment get reduced along with the dependence on trained personnel.
According to reports, doctors believe that eventually, it can be self-administered and is likely to have lesser safety events.
What are the drawbacks of the intranasal vaccine?
The first intranasal vaccine was administered in the 1960s after the rollout of the oral polio vaccines. However, even after administering the same, it was noted that the virus was still contracted by a person.
Experts say that there are very few proven cases to back the effectiveness of the route of the virus. Although intranasal vaccines have been well tested in animals, the effectiveness of the same in humans is yet to be proven.
